i te \ ST & Y OP £ fvT 8 -0 ?"" ' El 250-500 /,y S }~ : y J ~ "'- ■' 1 il 1000 + introductâon continued Figure 1.3: Farmland by watershed Legend {Ian*} II OS £ 5-20 fjX S 2O40 ' ''"' !C>- - ~ 4O-60 ?"' t ? *) il 6O-S0 sS '"< S il 8O-10O .4 f«* --^:-' ' ^' : a third of Canada's population - call Ontario home. Most of them - more than 80 per cent - are urban dwellers, and nearly half of them live in the Golden Horseshoe, the megalopolis stretching around the west- ern end of Lake Ontario from Oshawa to St Catharines. Altogether, close to 90 per cent of the population lives in southern Ontario, a region that comprises about 10 per cent of the province's area (Figure 1.2). In addition, Ontario is Canada's most highly indus- trialized province, accounting for more than 40 per cent of its industrial output There are more than 22,000 mills, smelters, factories and other industrial facilities in the province, involved in such activities as pulp and paper production, metal processing, petroleum refining, chemical production, food processing and many other types of manufacturing. Maintaining and expanding this industrial output requires the consumption of large quantities of energy and resources and results in the re- lease of air pollutants, water pollutants and hazardous wastes. The impact of industrialization is greatest in south- ern Ontario, where the vast majority of these plants are located. Half of them are in Metropolitan Toronto. Most of the rest are in other localities within the Golden Horseshoe or in the Sarnia- Windsor region. In the north, industrial activity is much more dispersed and 3 introduction continued is focused primarily on resource processing operations such as pulp and paper mills and metal smelters. Industrial pollution, however, is not the only source of environmental stress. Agricultural pesticides and her- bicides are a significant source of toxic chemicals in both air and water, and chemical fertilizers, and live- stock wastes contribute to water pollution. The impact of agricultural pollution is most evident in the south- western and southeastern counties, where about 50 per cent of the land is under cultivation (Figure 1.3). In the north, mining and forestry impose additional stresses on the environment. Both can significantly alter or disrupt wildlife habitat. Poor forestry practices may also cause soil erosion, pollution from pesticide and her- bicide use, and depletion of the forests themselves if care is not taken to regenerate areas that have been cut Min- ing also may produce acidic and toxic wastes that can contaminate ground and surface water. Abandoned mines are a further source of these contaminants. The conveniences of modern day living are also sources of pollution. Car and truck emissions contribute to urban smog. Fridges and air conditioners contain chemicals that deplete the ozone layer. Towns and cities continually generate sewage and garbage which require proper treatment and disposal. Even ordinary household items such as paints, cleaners and cosmetics can be sources of harmful pollutants. Moreover, a society such as ours has a large appetite for energy - to power industries, heat homes and run cars. Much of this energy comes from fossil fuels, such as gasoline, oil and natural gas. In fact, 77 per cent of the energy used by Ontario consumers is derived from fossil fuels. Ontario's motor vehicles alone use more than 15 billion litres of gasoline and diesel fuel a year. Electricity also supplies many needs, but about a quarter of what Ontario generates comes from the burning of coal and other fossil fuels. The rest is produced by nuclear power (48 per cent) and water power (29 per cent). The production of this energy imposes both costs and risks on the environment The burning of fossil fu- els contributes to urban air pollution, global warming and acid rain. Nuclear energy creates radioactive wastes that are difficult to dispose of safely and hydro power can have major impacts on watersheds and wildlife habitat For the most part, environmental problems that are created in Ontario have their greatest effect in Ontario. But because ecosystems know no borders, Ontario's en- vironmental quality affects and is affected by the envi- ronmental quality of surrounding regions and other parts of the world. A clean environment is something we owe both to ourselves and to the rest of the global community. Air is a mixture of many different kinds of gases and suspended particles. Most of these come from natural sources. Others are created and released into the air as a result of human activities. When concentrations of some of these gases andparticles become too high, they can harm human health and damage the environment Air pollution linked to human activity comes from point sources such as large factories or thermal-electric power plants and from area sources such as motor traffic or household furnaces. Some of the gases and particles released from these sources affect only the area near the source, but others may be carried by air currents, affect- ing areas hundreds of kilometres away. Air pollutants affect the environment in at least three ways. They can directly damage thehealth of plants and animals that breathe the air. They can conta- minate other parts of the environment such as soils and water. And they can change the makeup of the atmos- phere and the way in which some of its most important processes function. The chapters in this section look at four aspects of air quality that face Ontario residents today: common air pollutants, toxic air pollutants, stratospheric ozone depletion, and global warming. Some hsc-haîc-hts from th-> section: Ontarians are polluting less. Emissions of some of the most common air pollutants, such as sulphur dioxide, nitrogen dioxide, airborne partkks and carbon monoxide, have de- clined over the last two decades, in some cases substantial- ly» Emissions of sulphur dioxide, for example, feD by 73 per cent between 1970 and 1992- In Ontario, there has been less success in dealing with ground-level ozone more commonly known as smog. Aver- age ground-level ozone concentrations were higher at the end of the 1980sthan at the beginning. Because of its expo- sure to ozone-laden winds from the United States, south- western Ontario was affected most frequently by ground- level ozone pollution. Fiftypercent of ground-level ozone measured during high ozone periods was transported from the American mid-west Odours from reduced sulphur compounds such as hydro- gen sulphide (rotten egg gas) are still a major problem in piaces such as Fort Frances and Cornwall, which bave kraft pulp mils. Since the introduction of unleaded gasoline, the concentra- tion of lead in outdoor an has declined dramatically. How- ever, -concentrations of manganese, used as a substitute for lead in gasoline, are increasing. In outdoor air in Ontario, concentrations of toxic com- pounds such as benzene, formaldehyde and dioxins and fiirans are generally very low. The high altitude ozone layer over Toronto has thinned by about four per cent since the late 1970s. Between 1986 and 199i,Oatario cut its use of ozone depleting substances by 50%. Since 1 890, average annual temperatures have risen by 0.5*C in northern Ontario and by 0.6'C in the south- Ontario is Canada's largest producer of carbon dioxide in terras of total emissions but ranks only seventh among the provinces in emissions per head of population. air continued Chapter 2 Common air pollutants The most common air pollutants in Ontario are sulphur dioxide (S0 2 ), nitrogen dioxide (N0 2 ), carbon monox- ide (CO), total reduced sulphur compounds (TRS), par- ticulate matter (PM), and ozone (O3). While all of these contaminants occur naturally, hu- man activity increases these natural levels substantially. At higher concentrations most of these pollutants are a health hazard, affecting the respiratory and cardiovascu- lar systems and making breathing more difficult, espe- cially for people with chronic respiratory diseases. A number of them also damage plants and crops and speed up the aging of plastic, rubber, dyed fabrics and other materials. Some have foul odours or form a dirty haze that decreases visibility (Table 2.1). High air pollution levels usually occur in urban or industrial centres due to emissions from traffic, factories and buildings. But rural areas are sometimes affected as Pollutant Table 2.1 Common Am pollutants and thesr effects Sources Health effects Other effects Sulphur dioxide Nitrogen dioxide Smelters, utilities, primary metal industries* refineries» mining, and other sources Transportation {vehicle, ak, rail), Utilities, industrial processes, primary metals, other sources Respiratory irritants. Increase vul- nerability to respiratory diseases and aggravate existing respiratory ailments. People wits asthma, bronchitis, other chronic lung diseases and heart disease are parucuferfy sensitive. Damage to plants. Acid rain. Dam- age to materials. Metal corrosion Damage to plants. Acid rain. Odour, Haze. Damage to materials {metal corrosion, fading of dyes, cracking of plastic and rubber). no direct source, formed by combination of nitrogen oxide and hydrocarbons Damage to plants. Damage to materials (fadingof dyes, cracking of rubber and plasties). Carbon monoxide primarily vehide, other trans- portation, chem ical industries, primary metals Asphyxiant Reduces amount of oxygen in blood. Cardiovascular stress, impairment of vision and ability 10 do complicated tasks; People with heart disease and smokers most affected. Particulate matter transportation, primary metals, Respiratory irritant. Particles also Damage to plants. Soiling, pulp and paper mills, utilities, fuel may have toxicsubstances bonded Corrosion. Reduced visibility, combustion to them. Reduced sulphur compounds reduced sulphur compounds: steel industries, refineries, pulp and paper raifis, chemical plants Odour B well, when pollution is carried by air currents. The time of day and the weather can also have an important effect on pollution levels. The quantity of a particular pollutant in outdoor air at a certain time and place is known as the ambient concentration. Ambient concentrations of the six com- mon poDutants have been monitored regularly across Ontario since the early 1970s. This monitoring program not only helps to identify pollution risks but also pro- vides information that can be used to indicate long-term pollution trends and measure the effectiveness of pollu- tion control measures. Ontario has set air quality criteria (AQCs) for each of these six pollutants which indicate when pollution levels become too high. The criterion is given as an average ambient concentration for a certain length of exposure such as a day, an hour, or a year, and it marks the point at which the pollutant becomes potentially harmful How clean is; Ontario's a«*? Ontario's air quality has improved substantially over the past twenty years. Ambient levels of sulphur dioxide, carbon monoxide, suspended particles and ni- trogen dioxide have all declined - in some area substan- tially. The sharp reduction in levels of sulphur dioxide alone represents a major advance in public health. Stud- ies conducted by the Urban Air Group at McMaster University suggest that every one part per hundred mil- lion increase in average annual sulphur dioxide levels re- sults in one extra doctor's visit per year for every person in the province. Still, some serious air quality problems remain. Ground-level ozone levels have shown a resurgence in the last few years. In places where industry and vehicle air continued traffic are densely concentrated, pollution levels rise rapidly when weather conditions favour their buildup. As a result, many centres in the province continue to experience periodic episodes of moderate to poor air quality. A useful indicator of overall air quality around the province is the Air Quality Index (AQI). Published since 1988, the index is based on individual readings for each of the common pollutants and is presented as a single number. As Table 2.2 shows, the index is divided into five categories, depending on the possible health, vegeta- tion, property, and aesthetic effects of different levels of pollutants. A special component of the Air Quality Index - the Air Pollution Index (API) - measures 24-hour running averages of sulphur dioxide and particulate matter. If the API reaches unacceptable levels and weather conditions favour a buildup of these pollutants, the government can order major emitters to reduce or cease operations. Some vegetation begins to show adverse effects from air pollution when the Air Quality Index enters the moderate range (index values 32-49). Aesthetic effects such as odours, haze, and soiling of materials are also evident in this range. Effects on human health are gener- ally not noticeable until the index passes 50 and depend on the pollutant involved. Ozone, carbon monoxide and nitrogen dioxide are considered health threats when concentrations are in the poor range (index values 50- 99). People with respiratory problems are the first to be affected, but as the index rises the number affected in- creases. Figure 2. 1 shows the number of days at various monitoring sites for which the Air Quality Index was above 31 for one hour or more during 1992. Almost all these instances of readings higher than 3 1, however, air continued were in the moderate range and are unlikely to have been a threat to human health. The very high number of readings above 31 at Fort Frances and most of those at Cornwall were due to reduced sulphur compounds, which are not a health hazard. For most other Ontario communities, ozone and suspended particles were the main pollutants. Altogether, only five locations reported AQI values greater than 50 in 1992, and in only one of these (Windsor College Street) was there actually a risk to health. That occurred at the College Street site in Table 2.2 Ontario's Air Quality Index Windsor, where ozone concentrations were in the poor range for a period of four hours. The same site also recorded the highest AQI level for 1992 (a value of 71, due to suspended particles). Although poor air quality days do occur, in general the health risk from outdoor air in Ontario communi- ties is low. To measure effectiveness in controlling air pollution, the rest of this chapter looks at how emissions of each of these pollutants has changed over the past 10 to 20 years. Total Sulphur Suspended Air pollution reduced monoxide dioxide Ozone dioxide particles index API sulphur Category Range CO N0 2 °3 SÛ2 SP (SOgwidSPJ TRS verygood «-15 No «Beets No effects No effects No effects No effects No effects No effects Good 16-31 No effects slight odour Injurious tc some vegerarion species in combination witftS02 (4 hours) Injurious to some vegetation species in combination with O3 (4 hours) No effects No effects Slight odours Moderate 32-49 Blood Odorous Injurious to Injurious to Some decrease Injurious to odorous chemistry but many some specks in visibility vegetation due no détectable yegetation of vegetation toS02 impairment species Poor 50-99 increased Odour and Decreasing Odorous. Visibility Increased Extremely cardiovascular discoloration. performance Increasing decreased. symptoms in odorous symptoms m. Some increase by athletes vegetation Soiling patients with smokers -with in bronchia! exercising damage evident chronic heart disease reactivity m asthmatics heavily respiratory disease Very poor 5I0Q Increasing Increasing Light exercise Increasing Increasing Significant Sensitive cardiovascular sensitivity of produces sensitivity in sensitivity in respiratory individuals symptoms m patients with respiratory patients with patients with efiectsin may suffer non-smokers asthma and efiectsin asthma and asthma and patients with nausea and with heart bronchitis patients with bronchitis bronchitis asthma and headaches disease. Some chronic bronchitis due to severe visual pulmonary odour impairment disease Sulphur dioxide Sulphur dioxide is a colourless gas produced by the combustion of sulphur-containing fuels like oil and coal and by certain industrial processes. In 1992, Ontario industries, businesses, and households released about 900,000 tonnes of it to the atmosphere. Approximately 75 per cent of this amount came from electric power stations burning coal and oil and non-ferrous metal smelters and sintering plants using high-sulphur ores. (Sintering is a roasting process for concentrating ores.) Most of the remaining emissions came from iron ore smelters, petroleum refineries, pulp and paper mills, and home, office and factory heating. Because it is the principle component of acid rain, sulphur dioxide has been the focus of some very strenu- ous and successful efforts to reduce emissions. Between 1970 and 1992, province-wide emissions of SOi de- clined by 73 per cent, thanks to tighter emission con- trols, improved process technology, and conversion to low-sulphur fuel Emissions from smelters alone de- creased by 80 per cent over the same period (Figure 2.2). By the end of 1994, Ontario's overall S0 2 emissions are targeted to reach 885,000 tonnes, with most of the re- ductions coming from Ontario Hydro, the smelting op- erations of Inco and Falconbridge, and the sintering operations of Algoma SteeL As emissions have declined, ambient concentrations of sulphur dioxide have also declined. Between 1971 and 1992, the yearly average of ambient sulphur dioxide concentrations for all monitoring sites in the province decreased by about 83 per cent (Figure 13). In 1992, the highest concentrations were recorded in industrial cities such as Sarnia, Hamilton, and Sudbury, where there were thermal power stations, smelters, or petrochemical air continued Bgvkz 2.1: Number of days with moderate/poor aîr. quality B*OtfURiQî991 number of days 200 "" ' ISO I t t : K 1 , sljSfSjfifiMlSii 33 *! t l tn 2 §. £ m gQ * ,? I- H ^ JZT >± FJGURE2.2: SoiPtreR djqxide emissions m Ormmx 1970- 1992 Emissions {thousands of tonnes} 3330' '""' 3000 '"if § acoo ;: ^ NSscaianeous £■ Cthar industrial processes ^jSmefcers : Becsicai utïôee PKU8E 2.3: AVERAGE ANNUAL SUtPKUR BÏCKÏÏJE CONCENTRATIONS IKOMTAKO, 1971- 1992 Mean concentration (ppbj Ontario annua} AOC Hi Ellin 1 1 1 ES II III ° T\ 7273 74 757677 78 73'80'81 •82'83 , S4 -SS-Sfi-S? '88'89'9031 "3S Note: 12 stes operated over 22 years air continued Figure 2.4: Local sulphur dioxide concentrations* annual average, 1992 ppb fsflsIfSMfi' ïl W5 f I ill s- 2 *.* 8 ! *° i Figure 2 .5: Emissions of nitrogen oxides in Ontario 1983-1992 600 2 Eteir**uMJe5 500 400~ 3O0 aoo 100 I !" J | B3 '84 *85 ^^J TrsnsportaDor L i 87 -88 '88 '30 'SI '9a Figure 2£: vehjoes - kilomètres travelled in Ontario Vehicle km |bilBons)_ __ !Hl P««<»>9«r =« £ij Heev t^ x ? ^L Tib? 100 H Kll 1) S; Ë; B ^ ■83 '84 "85 '86 "87 '68 "89 '30 '31 '32 refineries (Figure 2.4). However, none of these places exceeded the annual air quality criterion, although a total of 15 locations ( 13 of them in the Sudbury area) exceeded the one-hour criterion at least once. Nitrogen dioxicta The air around us is mostly a mixture of nitrogen and oxygen - about 78 per cent of the former and about 2 1 per cent of the latter. Whenever anything is burned in air at a high temperature, as in a furnace or a car engine, these gases combine readily to form various oxides of nitrogen. The most common of these is nitrogen diox- ide, a reddish-brown gas with a pungent and irritating odour that is commonly seen hanging over cities during the summer. About 60 per cent of Ontario's nitrogen oxide emis- sions come from various means of transportation, most- ly from motor vehicles. Other sources include thermal- electric generating plants, incinerators and chemical processes. Altogether, Ontario produced nearly 450,000 tonnes of nitrogen oxides in 1992. Nitrogen oxide emissions had remained fairly con- stant during the 1980s, but fell by more than 20 per cent between 1989 and 1992 (Figure 2.5), thanks largely to the introduction of new vehicle emission standards. These resulted in a significant decrease in transportation emissions, even though Ontario vehicles recorded an in- crease in total kilometres travelled (Figure 2.6). Because motor vehicles are the major source of emissions, getting nitrogen oxide emissions down - and keeping them there - is a difficult long-term propo- sition. Better technology and regular inspection and maintenance can reduce the emissions per vehicle. But every additional car or truck on the road is a new source 10 of emissions and the number of vehicles in Ontario con- tinues to increase from year to year. The yearly average of nitrogen dioxide concentra- tions at monitoring sites in Ontario improved by about 13 per cent between 1975 and 1983 and this has re- mained fairly constant since then (Figure 2.7). The high- est levels are normally found in larger cities, especially during rush hours when traffic density is greatest. How- ever, there were no instances of exceeding the hourly air quality criterion in 1992 (Figure 2.8). air continued FiGURH 2.7: AVE&AGE ANNUAL JsTTKOGEN CK»QD£CONCES7SATK)KS IK OKTAXiQ, 1975- 1992 Mean concentration tppo) 10 g till in 1 1 1 1 it 1 1 ï ° 75 76 77 *7S 73 SO "8+ - 82 "83 -84 '85 86 87 '88 S3 "SO '91 '9S Note: 15 sites operated over 18 years Carbon monoxide Carbon monoxide is a colourless, odourless gas that forms when carbon fuels are burned without sufficient oxygen. The use of various forms of transportation is responsible for about 75 per cent of emissions, with the burning of fossil fuels for home heating and commercial and industrial operations accounting for most of the rest In spite of an increase in the number of vehicles on the roads, carbon monoxide emissions have declined by about 30 per cent over the last decade. In 1992, they to- talled nearly 1,900,000 tonnes (Figure 2.9) Lower emissions have generally led to improve- ments in ambient concentrations of carbon monoxide. By 1983, average annual concentrations had fallen by approximately 75 per cent from their levels a decade be- fore, and they have remained relatively steady since then (Figure 2. 10). Neither the one-hour nor the eight -hour air quality criteria were exceeded in 1992 (Figure 2.1 1). Figure 2.8: Local nitrogen ïhgxîde conœntrxtïoks 1-HOtiS MAXIMUM, 1992 ppb Ontario 1-hour AQC Figure 2S: Emissions ofgakbon monoxide m Onïàriq, 1983-1992 f|§*| Tnr«p MSX TRS CRFTERJON WAS EXCEEDED, 1992 number of times exceeded RGURF 2.14: PàRTICUIXTE EMISSIONS, ÎN ONTARIO, Ï 983-1992 Wflffi g mdustTBt crocases Emissions (thousands of tonnes] see | i TransporQùor. ? fcfectMrecuc •83 '84 -S5 | | | g | | | •88 «? '88 "83 '90 '91 '32 Figvre 2.15; Average annual TSP concentration in Ontark>, 1971-1992 Mean concentration [microgr ams/m 3 ) tab il 1 1 1 si II Si I Ontario annual AQC 1(1; II ill ill III § i S 71 72737475767778 73'80'61'82'83'84'85'ee'87'66 BS'90'91 92 13 air continued Figure 2.16: Average annual TSP concentrations in select uacAirriES, W92 micrograms/m Figure 2.17: Ontario VOC emissions bï sector Refineries 5% Other point sources S% Other transportation S% Misc. area sources 13% Surface coating 16% Ground-ievei ozone Ozone is a form of oxygen, made up of three oxy- gen atoms instead of the usual two. At high altitudes it filters harmful ultraviolet radiation from incoming sunlight, but at the earth's surface it is an unwelcome pollutant Small amounts of ozone form and break up natu- rally in clean air at the earth's surface as a result of the action of sunlight on nitrogen oxides (NOx). In polluted air, however, ozone formation is increased by the higher levels of nitrogen oxides reacting with other chemicals — notably volatile organic compounds ( VOCs) , that evaporate from sources such as gasoline and solvents. Weather conditions have a considerable influence on surface ozone levels. Air masses can carry ozone or its nitrogen oxide and VOC precursors over several hundreds of kilometres. Levels can soar during summer hot spells, when dry, sunny weather favours ozone for- mation and stagnant air masses prevent its dispersal. Indeed, ground-level ozone is primarily a summer pol- lutant Ozone is a major component of photochemical smog and forms near or downwind of sources of NOx and VOCs. Motor vehicles are a major source of both groups of substances. Other major sources of VOCs in- clude a variety of solvent-based materials, from printing inks to nail polish remover, and surface coatings such as paints and varnishes (Figure 2.17). In spite of increased vehicle usage, VOC emissions have remained fairly close to the 1987 level of 630,000 tonnes per year throughout the past decade. Like nitro- gen oxides they have also shown a moderate decline since 1990. In the case of VOCs, this can be attributed to new vehicle emission standards, changes in the composi- tion of gasoline used in the summer and the effects of economic recession. Natural sources such as forests and forest fires also release significant quantities of VOCs to the atmosphere. In tact, emissions from natural sources may be as much as three times greater than those from sources related to human activities. Although towns and cities are major sources of both NOx and VOCs, ozone pollution is not exclusively an urban problem. Approximately 50 to 60 per cent of ground-level ozone concentrations in Ontario blow into the province from sources south of the lower Great Lakes (Figure 2.18). In rural areas in the path of these air streams, ozone levels often exceed the provincial one- hour air quality criterion. Indeed, instances of exceeding the criterion have been more frequent at rural sites in southwestern Ontario than in large cities such as Toron- to and Hamilton - and certainly far more significant than at rural sites such as Hawkeye Lake, north of Thunder Bay, which are not exposed to the same air flow (Figure 2.19). air continued Figure 2. 18: Areas from which air arrives during high ozone periods !n southern ontario 1583- 1992 Nats: the movement of these air masses from south of the Great Lakes U> Southern Ontario transport 50-60% of the ozone and precursors measured during high ozone periods. Figure 2.19: Number of instances where 1-hour ozone criterion was exceeded at selected idcalitï es, 1985-1992 number of bmss exceeded 20X Note: * Urban sites Ontario 1-hour AGI s SO ppb 15 air continued Figure 1 JtCfc Average ozone concentration and instances WHERE CRITERION WAS EXCESSES IN ONTARIO, 1983-1992 t<.*ana J J Pill Kllilliit., *■ o,s ..«.> «S «à «£• «i- —£ «*■ ™S ™> w» ™> «*■ «5-^lf e»"*s*' *•>■■ *71 72*7374*75 7877 7873 "8 0*81*82*83* 84 "85 38 "87 "88*83*30 "31 32 of their high toxicity and their prevalence in the atmos- phere. These substances include two heavy metals, five organic compounds commonly found in urban air, and dioxins and furans. He«vy Svlecais Small quantities of some metals, such as iron, are essential to the human body. Others, such as lead, mer- cury and cadmium are highly toxic, especially to the kidneys and the nervous system. This section focuses on two metals, lead and manganese. Lead particles are the most common heavy metals in the air. Lead is especially toxic to children, who ab- sorb it much more readily than adults. Until recently, the largest single source of lead in the atmosphere was leaded gasoline. However, with the introduction of un- leaded gasoline in Ontario in 1974 and the subsequent phasing out of leaded fuels over the next decade and a half, the presence of lead-contaminated particles in the air has dropped dramatically (Figure 3.2). Some 840 tonnes of lead are still emitted to the at- mosphere annually, most of it (about four-fifths) from mining and metal processing operations (Figure 3.3). The highest atmospheric lead levels in the province are now found near lead processing plants in Toronto and Mississauga. Because high concentrations of lead may still occur in the vicinity of such point sources, their emissions are closely monitored to ensure they do not exceed the provincial standard of 5 micrograms per cu- bic metre of air for 24 hours. As ambient concentrations of lead have declined, however, those of another metal, manganese, have in- air continued Figure 3.3: Ontario leao emissions sy sector Figure 3.4; Average annum concentration of manganese inTSP in Ontario 1983-1992 Annual mean concentration (micrograms/m 3 ) 006™ "83 B4 *85 *86 '87 *88 '89 "SO *91 *92 Note: 10 sites operated over 10 years creased. Manganese was used as a substitute for lead in unleaded gasoline. Annual average concentrations of manganese increased steadily throughout the 1980s and were almost twice as high at the end of the decade as they were at the beginning (Figure 3.4). Although man- ganese has industrial uses, its more recent use as a sub- stitute for lead in gasoline likely accounts for the rise in manganese concentrations. 19 air continued Figure 3.5: Medïan ai» concentrations at selected locAimES microgra ms/nrp "s ■MB; BertfBfe fggjMathitaneCnvrtie : v^ Perchloroam^na 1CÏÏI s S 5 5 I fi s. m Manganese is an essential element in people's diets and, in feet, most of the manganese in people's bodies comes from food. Health effects do not occur from low level exposure to manganese in air and food. However, exposure in more concentrated doses can lead to harmful effects. Miners and metal workers exposed to high levels of manganese dust sometimes experience a syndrome known as manganism, which is marked by mental and emotional disturbances and slowness and clumsiness of movement. So fer, manganese concentrations around the province have been well within the MOEE's guide- lines. Note: MOEE guideline far methylene cHonde s 1 765 merograms/m^'24 hrs. MOSE gindeine fro PCE is 4000 mcrogram s /mySA hours Interim guideline far benzene to be introduced in 1 394 Table 3.1 : Ambient concentrations of B(a)P, Dkhhns, Forans ANB FORMAJUOEHyOE XT SELECTED lOCAllTlES Site B(a}F {ng/m 5 } Dorset 0.0 Toronto Island Windsor O.J (downtown) Windsor 0.0 {College/ Prince) Windsor 0.1 {Wright; Water) Ottawa Sault Ste. 0.9 Marie Thunder Bay 0.1 Guideline 0.3 (ng/m 5 } Dioxins/ F-urans fpg/m 1 } U9/0.40 J .06/0.92 334/4.90 30pg/m* Formaldehyde 1 (jig/m3) 2-16 2.05 65 jig/m' 1 Environment Canada data Urban air tenses Of all the toxic chemicals that come from typical city sources such as industries and motor vehicles, those of greatest concern are formaldehyde, benzo(a)pyrene [B(a)P], benzene, methylene chloride and perchloroeth- ylene (PCE). Formaldehyde is widely used as a fungicide and preservative and as a raw material in the manufacture of plastics, plywood and particle board. B(a)P, a byproduct of the incomplete combustion of carbon fuels, is found in wood smoke, cigarette smoke, diesel exhaust and coke oven emissions. Benzene is an easily vaporized compo- nent of gasoline and is also found in the exhaust gases of gasoline engines. Methylene chloride is used commonly as a paint remover and degreasing solvent, and is an in- dustrial byproduct, while PCE is a degreasing solvent and a dry cleaning fluid as welL All of these compounds are either known or probable carcinogens. PCE and B(a)P are also highly persistent in the environment SO Concentrations of urban air toxics in almost all lo- calities, though, have been well below current provincial guidelines. The highest normally occur in urban indus- trialized areas such as Toronto, Hamilton, and Windsor. As might be expected, the lowest levels of toxic contami- nants are usually found at rural sites, such as Dorset near the southwest boundary of Algonquin Park Be- tween 1989 and 1992, one of the air toxics guidelines, for B(a) P, was exceeded on a number of occasions. These elevated levels were recorded at a site adjacent to the Al- goma Steel mill in Sault Ste. Marie, and at several moni- toring sites in Hamilton. MOEE and Environment Canada began to monitor ambient air concentrations of these chemicals in 1989. Figure 3.5 shows ambient air concentrations for ben- zene, methylene chloride and PCE at several locations in the province between 1989 and 1991. Table 3.1 shows ambient concentrations of B(a)P and formaldehyde at selected locations for the same period. In both cases, these concentrations are median - or mid-range - values. These levels - like those of most other air pollutants - can vary considerably over a short distance. While downtown Hamilton, for example, had the highest mid- range value in the province for methylene chloride, an- other site in the city had no detectable level and a third recorded only a trace. As yet, no provincial guidelines for benzene have been set, but mid-range values run from a low of 0.35 micrograms per cubic metre at Dorset to a high of 8.30 micrograms per cubic metre at a site in Hamilton ex- posed to emissions from major traffic routes and nearby steel mills. Readings at other sites have been closer to the lower end of this range. air continued Dioxins and furans There are more than 200 different varieties of poly- chlorinated dioxins and furans. These highly persistent compounds are commonly produced as byproducts of combustion or chemical processes involving chlorine. Prolonged exposure even to very low doses of some of these substances has produced cancer in laboratory ani- mals. Average concentrations of dioxins and furans in outdoor air have been measured at three sites in Ontario: Toronto, Windsor, and Dorset (Table 3.1). Sur- prisingly, levels at Toronto were very similar to those at Dorset The similarity underscores the fact that dioxins and furans come from a wide variety of sources - mostly from industry and traffic in Toronto and wood burning in Dorset The highest levels were recorded at Windsor, where there is a large concentration of industrial sources. Al- though levels there were three to four times higher than in Toronto and Dorset, they were still well within the current provincial guidelines. Some industries in Sarnia and Hamilton, and pulp and paper factories that use chlorine in their processes are also sources of dioxins and furans. Setting standards to protect human health Not enough is known yet about the effects of sus- tained exposure to very low levels of these pollutants over many years and decades. Most of what is known about their toxic effects is based on exposure to much larger doses in the workplace or on laboratory experi- ments on animals whose bodily processes may differ in important ways from those of humans. Where there is air continued evidence of the long-term effects on humans, it is often complicated by other factors and therefore difficult to interpret Because of this lack of direct information, guideline levels for environmental exposure are set very cautious- ly. They are usually based on the dosage at which no adverse effects are observed in laboratory animals. A large safety factor is then added to produce the guideline value for humans. However, the evidence on the effects of long-term exposure to low levels of these pollutants are monitored to determine that the safety factors are adequate in all cases. For this reason, MOEE will continue to review its guidelines and modify them as more information be- comes available. Jllpl EjtrïlZ'J'r&iiSB "^*: Jet Airliner 10km 'h'opypziliziS sas « s ssassst ft ft aasass s s ssa Ti'upDSfjhars Mount Everest 8.8 km Température profile of atmosphere >£ * I "■n. l ^- ■Ml Mill Ml \ atratonpnarç. *s I — V f / / tropcba*e -V --* Orcre Concentration (pom) 10 -7S S3 -25 TemperaUre t* Q Limit of most clouds 11 km Supersonic Aircraft 15 km Ï Figure 4. 1 - The Vertical Structure of the Atmosphere The atmosphere is divided into several layers. The lowest layer, the troposphere, extends 10-1 5 km above the earth's surface, and is where most weather activity takes place. Next is the stratosphere which extends 50 km above the earth's surface and contahs the ozone layer The boundary between the two layers is called the trop o pause. air continued Chapter 4: Statospheric ozone Figure 42: CFC use in Canada by sectors, 1991 The stratospheric ozone layer, located 25 to 35 km above the earth's surface, makes up no more than 5/10,000 of one per cent of the atmosphere's total mass at a concen- tration of about 8 to 10 parts out of a million (Figure 4.1). Yet this thin, wispy veil of gas is a crucial compo- nent of the upper atmosphere. The ozone layer acts as a protective shield for life below by absorbing the sun's harmful ultraviolet rays before they reach the earth's surface. As an absorber and emitter of warming infrared radiation, ozone also plays a critical role in shaping the structure of the atmosphere and determining the patterns of the world's climate. Fears about the possibility of human damage to the ozone layer have been around since the 1960s, but they were confirmed dramatically in 1985 with the discovery of the Antarctic ozone hole - a continent-sized area of severe but temporary ozone depletion that develops every September and October. In most of the rest of the world, ozone depletion has been much less severe but still noticeable. Over the middle latitudes of North America, it appears to have been occurring at the rate of four to five per cent per decade. Research has shown a strong link between the destruction of stratospheric ozone and the chemical activity of several widely used chlorine and bromine compounds. The best known of these are the chloroflu- orocarbons (CFCs), used as refrigerating and air condi- tioning fluids, solvents, and foaming agents (Figure 4.2). Others include halons (bromine compounds used in fire Foam 35% Misc. 5% Solvent 9% Refrig. & ar cond. 28% Mobile air cond. 23% Total Cf Cs = 9.000 metric tonnes CFCs and halons are responsible for most ozone depletion. Environment Canada estimates that Canada accounts for 1.7 per cent of the world's supply of these chemicals, and Ontario is the biggest producer and user in the country. One thing these chemicals have in common is a very long lifetime in the atmosphere, ranging from about six years for methyl chloroform to several hun- dred years for some of the CFCs. This is long enough to allow them to migrate into the stratosphere. Once there, they are broken down by intense ultraviolet radiation, releasing chlorine or bromine atoms. These react with Figure 43: Destruction of ozone by chlorine A+ mm p Oxygen Î ;T Chforine monoxide extinguishers), methyl chloroform (a metal-cleaning agent) and carbon tetrachloride (used mostly in the making of CFCs). Oxygen Oxygen «^ atom [ 1 air continued ozone, destroying it in the process and forming new, unstable chemicals that soon split apart, releasing the chlorine or bromine to begin the process again. In this way, each chlorine or bromine atom has the capacity to destroy one hundred thousand or more molecules of ozone (Figure 4-3) As the amount of ozone in the stratosphere de- creases, we can expect more ultraviolet radiation to reach the earth's surface. Some varieties of UV are more destructive than others. Fortunately, the most powerful, UV-C, is entirely screened out by the ozone layer. The least powerful, UV-A, is only partially absorbed, and most of it reaches the Figure 4.4: Total ozone Dob son units ~38D Note: 1 DO Dobson unies are e at sea tevst pressure an earth's surface. However, it is the middle variety, UV-B, that causes most concern, because it is still very potent and able to do a good deal of biological damage. Under normal conditions, some UV-B penetrates the ozone layer, but as ozone amounts de- crease, a significantly greater amount can be expected to reach the earth's surface. UV-B stimulates the formation of vitamin D in the body, but too much of it causes sunburn and speeds up the aging of the skin. Repeated overexposure can lead to skin cancer, as well as cataracts and other eye diseases, and may damage the immune system. Among light- skinned peoples, skin cancer rates tend to increase to- wards the equator, where the ozone layer is not as dense and UV-B intensity is greater. Changes in the normal in- tensity of UV-B could also damage some plants, includ- ing food crops and some plankton that are essential to ocean and lake food chains. Q^ona toss over Ds^caHo The amount of ozone in the stratosphere varies with the latitude and season. It also can vary consider- ably from day to day and year to year at any given loca- tion. This natural variability sometimes makes it diffi- cult to analyze trends in ozone amounts. However, as Figure 4.4 shows, total ozone amounts began to show a noticeable decrease over Toronto in the late 1970s and declined by about levels over Toronto, 1960-1991 four per cent during the following decade. Data are not available for other locations in Ontario, but other sites in Canada show a similar pattern. More recently, the rate of ozone de- cline has increased, at least in part because of the tem- porary effects of volcanic particles from the eruption of Mount Pinatubo in the summer of 1991. A study of ozone over Toronto between 1989 and 1993 showed that winter concentrations decreased by an average of 4.1 per cent a year. During the same period, average summer concentrations declined by 1.8 per cent a year. Over the four years of the study, the intensity of UV-B radiation at ground level in Toronto increased by an average of 35 per cent annually in winter and 6.7 per cent in summer. 24 air continued It should be noted, however, that these are relatively large percentage increases of small amounts, and that UV-B levels in southern Ontario are still low in compar- ison to those found farther south. As the effects of the Pinatubo eruption fade, it remains to be seen whether ozone and UV-B levels return to values closer to those of the late 1980s. Nevertheless, as nature's first line of defence against ultraviolet radiation weakens, the sun's rays must be treated with more caution. To help Canadians avoid ex- cessive ultraviolet exposure, Environment Canada issues a daily UV-B index with its weather forecasts. The index uses a scale of 0-10 to indicate the relative amount of UV-B that can be expected, given the season, time of day and current weather. The higher the number is on the index, the greater the UV-B intensity and the faster your skin will bum when exposed. At a value of 10 - typical of a clear, summer day in the tropics - light, untanned skin will burn in less than 15 minutes. Stopping lite, damag e The international community has moved with un- usual swiftness and unanimity to halt the destruction of the ozone layer. In 1987, 24 nations met in Montreal to formulate an action plan for controlling ozone-de- pleting substances. By September 1992, the Montreal Protocol, as the plan is known, had been signed by 86 countries responsible for considerably more than 90 per cent of the world's CFC and halon supply. The protocol now requires all signatories to elimi- nate the consumption of halons by the end of 1993 and CFCs by the end of 1995. Carbon tetrachloride is to be completely phased out by the year 2000 and methyl chloroform by 2005. Hydrochlorofluorocarbons (HCFCs) have been authorized as a temporary substi- tute for CFCs. These are much less powerful ozone de- stroyers but still have some potential for damaging the ozone layer. They also contribute to global warming. Present agreements call for a phased reduction of HCFCs to begin in 2004 and to be completed by 2030. In response to the Montreal Protocol, Canada reduces its annual use of ozone depleting substances (ODS) from 20,000 tonnes in 1986 to 10,000 tonnes in 199 1 . Ontario accounts for approximately half of the to- tal use of ODS's in Canada. This 50% cut in only 5 years is due to strong provincial regulatory controls and swift industrial innovation. Even after production of these chemicals has ceased, thousands of tonnes of them - mostly CFCs in refrigerators and air conditioning systems - could still remain in use for several years. To reduce the risks from spillage or other accidental venting of these, Ontario re- cently introduced regulations banning the use of CFCs and HCFCs in new motor vehicle air conditioners, be- ginning with the 1996 model year. Pre- 1996 models would still be allowed to use CFCs. The regulations would also prohibit the venting of CFCs, HCFCs, and hydrofluorocarbons to the atmosphere. In addition, any- one servicing refrigeration equipment containing fluo- rocarbons will have to complete a brief training course and be certified by the province- How long will it take for the ozone layer to recover? The production of ozone-depleting substances is now declining sharply. But those released in the past continue to make their way into the stratosphere, and some of air continuée those still in use will do so in the future. As a result, levels of these chemicals in the stratosphere are still increasing. Scientists estimate that the quantity of ozone-destroying chemicals in the stratosphere will peak around the turn of the century and decline there- after. However, given the long lifetimes of these chemi- cals, it will be several decades yet before much of the current damage will be reversed and ozone levels in the stratosphere recover significantly. Chapter 5 Global warming The atmosphere provides a blanket of insulating gases that keep the earth's surface from losing heat too rapidly, thus maintaining a favourable temperature to support life. The insulating action of these gases is commonly known as the greenhouse effect and the gases themselves are known as greenhouse gases. Without the greenhouse effect, the earth would lose the heat it absorbs from the sun much more rapidly, leaving it, on average, about 33*C cooler than it is now — too cold to support life as we know it The most abundant greenhouse gases in the atmos- phere are water vapour, carbon dioxide and methane. Others include ozone, CFCs and nitrous oxide. The most significant characteristic of all these gases is their ability to absorb and re-emit infrared radiation, which is given off by the earth as it cools. Surprisingly, these gases constitute only a very small part of the atmosphere. Wa- ter vapour, which represents up to four per cent of the atmosphere's mass, is by far the most common and the most variable from place to place. Carbon dioxide, how- ever, makes up only about 355 of every million parts of the atmosphere, while methane constitutes only about 17 parts out of every ten million. All play a critical role in the earth's climate system. Studies of fossilized air in ancient ice from Greenland and Antarctica show a very close correspondence be- tween the amount of greenhouse gases in the air and the earth's temperature. Greenhouse gas concentrations are lowest during ice ages and highest during warm periods. Concentrations of greenhouse gases have been rising since the beginning of the industrial revolution more than 200 years ago. The most significant increase has been in the amount of carbon dioxide, which is now more than 20 per cent higher than at any time in the past 160,000 years and is increasing globally at a steady rate of about 0.5 per cent per year (Figure 5.1). Most of this increase has come from the burning of fossil fuels such as coal and oiL A smaller portion comes from the accelerated rate of clear cutting and burning the world's forests. Methane levels are now more than twice what they were in pre-industrial times. Methane comes from many different sources, including natural wetlands, rice pad- dies, landfills, coal mines, the digestive systems of cattle and sheep, and gas and oil extraction and transmission. Levels of other greenhouse gases - ground-level ozone, nitrous oxide, and CFCs - are also increasing. As greenhouse gas concentrations rise, the atmos- phere is able to hold more heat This should cause tem- peratures to increase significantly, but because the earth's climate system is so complex, how it will respond to these increases is not entirely clear. The climate sys- tem has several interacting parts, including not only the atmosphere but also the oceans, the continents, the polar ice masses, and all the earth's plants and animals. All these will respond in different ways to an increase in greenhouse gases and to any extra warming of the atmosphere. Some of these responses may moderate or offset any warming tendency. Others may intensify it Other characteristics of the climate system - such as rainfall and snowfall, evaporation rates, or the move- ment of weather systems - may change as weJL Scientists have developed elaborate computer models to help them predict how the climate system will respond to increased levels of greenhouse gases. Their predictions suggest that with a doubling of CO^ emissions, the earth's average temperature will increase by anywhere from 1.5"C to 4.5*C, with the amount of warming being least in the tropics and increasing towards the poles. Since the difference in average global temperature between the last ice age and the present is only about 5 to 6'C, even the lowest of these estimates could cause noticeable changes in Ontario's climate. Not only might it get warmer, but it might affect the amount and loca- tion of rainfall, or the frequency of droughts, the length of the growing season, or the water levels of the Great Lakes. These changes, in turn, could affect almost every- thing from the health of Ontario's forests to the kinds of crops we grow, to the efficiency of hydro dams. These changes would require personal and eco- nomic adjustments that could be difficult and costly. That's why, from both a provincial and global perspec- tive, global warming is a major concern. air continued Figure 5.1: Atmospherïc casbqn ûiqxide cokcestratjons 1959- t 992 Concentration [ppm) 360 Source: U.S. National Oceanic and Atmospheric Adrrarastraoon. Environment Canada Emissions themselves are not an actual indicator of warming. There must be evidence of long-term changes in global and regional temperatures and changes in tem- perature-dependent natural processes, such as the ad- vance or recession of glaciers and the freezing of lakes. Greenhouse gases come from both natural sources and sources related to human activity. Globally, natural sources of some greenhouse gases, such as carbon diox- ide and nitrous oxide, are much greater than the sources related to human activities. But in the relatively stable climate system that we have enjoyed since the end of the last ice age, nature has been able to remove greenhouse gases from the atmosphere at about the same rate as they were produced. The biological, chemical, and phys- ical processes that remove these gases are known as sinks, and they have also been able to remove a portion - but not all - of the greenhouse gases emitted by sources linked to human activities. It is this surplus of emissions from sources linked to human activities that is causing greenhouse gas concentrations to rise. I 27 air continued Ontario's greenhouse gas emissions In 1990, an estimated 166 million tonnes of carbon dioxide were emitted by sources related to human activi- ties in Ontario. By far the greatest part of these emis- sions, more than 90 per cent, came from the burning of fossil fuels for energy - for transportation, industrial en- ergy, electric power generation and heating (Figure 5.2). Methane is produced when organic matter decays in the absence of oxygen. In Ontario, about two thirds of the nearly 1.1 million tonnes emitted as a result of human activities in 1990 came from landfills and sewage treatment systems, while most of the remaining third came from cattle and Industrial processes 3% Landfills 1% sheep. Nitrous oxide emissions from human activities in the province totalled nearly 31,000 tonnes in 1990. Nearly 55 per cent of this came from the production of adipic acid, which is used for making certain types of nylon. Close to 40 per cent came from the burning of fuels. CFC emissions were estimated at 6,577 tonnes. These came mostly from the leakage or discard- ing of refrigerator and air conditioning fluids and the use of CFCs as solvents. Kilogram for kilogram, carbon dioxide is actually the least powerful of the major greenhouse gases, but because of the amount emitted it is the most important contributor to greenhouse warming. Per person, Cana- dians are among the top emitters in the world. In 1987, each Canadian produced an average of 18.4 tonnes of carbon dioxide from the burning of fossil fuels for Figure 5.2: Ontario carbon ï>îoxîde emisston sources, 1992 energy. To some extent, this is the result of special cir- cumstances - a widely dispersed population and great distances between major cities, a cold climate and re- source-intensive industries. But it is also a product of heavy dependence on fossil fuels and an extensive use of energy resources. Although Ontario is Canada's leading industrial producer, its carbon dioxide emissions, on a per capita basis, have been below the national average. In 1987, Ontario produced 16.6 tonnes of carbon dioxide per capita from energy- related emissions, ranking seventh among the provinces and 10 per cent below the national average. Globally, the com- parison is less favourable. The world as a whole produces about 22 billion tonnes of carbon dioxide a year from energy- related sources. Ontario's emissions amount to about 7 one-thousandths of that amount even though our population is less than 2 one-thousandths of the global totaL Between 1960 and 1979, Ontario's energy-related carbon dioxide emissions more than doubled, largely because of increases in population, industrial expansion and an improved standard of living that encouraged a greater use of cars and other energy-consuming devices. Since then, there has been a moderate decrease, with emissions for 1991 about 12 per cent lower than for 1979. Fossil fuel production 1% Stationary fuel combustion 52% Other, sewage treatment, prescribed Fires, agriculture, fugioiœ production emissions, refrigeration, closed csB foam» aerosols & solvents To some extent, improvements in energy efficiency have put a brake on the growth of carbon dioxide emis- sions, but the most decisive influence on emissions has been economic conditions. Decreases in emissions have usually coincided with periods of economic recession, as in 1975, 1979-82 and 1990-91. The only exception is the 1984-86 emission decrease, which resulted from an ex- pansion of nuclear generating capacity (Figure 5.3). Still, efforts to improve energy efficiency have been significant. As Figure 5.4 shows, the amount of carbon dioxide emitted for every $1000 of economic output has declined by an average of 2.5 per cent a year over the past two decades. Without these improvements in ener- gy efficiency, Ontario's carbon dioxide emissions would now be much higher. is the «arth getting warmer? Scientists estimate that the buildup of greenhouse gases during the past couple of centuries should already have caused the earth's average temperature to rise any- where from 0.4'C to 1.3'C during the past 100 years. Analyses of global temperatures, in fact, show an in- crease of about 0.5"C since 1861. The 1980s were the warmest decade on record and 1990 and 1991 were the warmest years. As Figure 5.5 shows, the warming has not occurred evenly, but has proceeded by steps. Temperatures began to rise in the 1890s, levelled off in the 1940s, and then began to rise again in the late 1970s. Nor has warming occurred equally in all parts of the world or even in all parts of Canada. In northern Ontario, the temperature increase since 1890 has been the same as the global aver- age, 0.5'C. But in southern Ontario, it has been slightly air continued Figure 5.3; Ontario energy-related carbon dioxide emissions, 1960-1991 Emissions I millions of tonnes) ISO _,.****... a .*'*• 160 a**** - «*• %/ ? «* 140 120 "" ■;■?"' 10O ■ : 80 ■: Figure 5.4: Ontarkj energy related carbon dioxide emissions per unit economic output Emissions (tonnes) per $ 1,000 Gross Domestic Product K ± x 11 m ' fc a»*«? 5 '!i 1.0 ~ as da "ÏL7 Figure 5.5; Global surface temperature trend, 1861-1992 Temperature change (T) Note: graph shows variations of annual temperature using a 30-year (1 950-79) average temperature as a reference peine (represented by the O'C line) Source: Oak Ridge National Laboratory 2B air continued FIGURE 5.6A:Tja*P£RATURE TREND IN NORTHERN ONTARIO, 1895-1992 1300 1310 1320 1330 1940 1950 1360 1370 1380 1390 Note: graph shows variations of annual temperatures using a 30-year (195079) average température as a reference point (represented by the O'c tine) Source: Environment Canada Figure 5.6b: Temperature trend in the Great Lakes - Sx Lawrence lowlands region, 1395-1992 1900 1310 1320 1330 1340 1950 1360 1370 1980 1990 Note: graph shows variations of annual temperatures using a 30-year [195079] average temperature as a reference point (represented by the O'c line) Source: Environment Canada more, 0.6*C (Figure 5.6a&b). As a whole, Canada has warmed by 1.0'C in the past century. The greatest warming has been on the Prairies and in the central sub-Arctic Parts of the eastern Arctic, however, have actually become slightly cooler. Further evidence of warming comes from studies of lake ice that Environment Canada has carried out at eight Ontario sites over the past two to four decades. The studies have noted a weak trend towards earlier freeze-up dates and a much stronger trend towards ear- lier break-up dates, resulting in a general shortening of the ice seasons at these lakes. Although this evidence suggests a slight cooling of temperatures in the late 611, it is offset by a more substantial warming in the spring. These trends may indicate changes in precipitation and other climatic elements as welL Clearly, some warming has occurred. But can this be attributed to a human-induced buildup of the green- house effect? So far, it cannot be so attributed with com- plete certainty. Climate is naturally variable, and there have been periods within the past 10,000 years when temperatures have been as warm as they are now or even slightly warmer. However, there is a reasonable probabil- ity that increasing levels of greenhouse gases are the cause. If this is so, then global temperatures within the next century can be expected to rise to higher levels than at any time in the history of human civilization. Stowing the buiîdup «f greenhouse gases It will take at least another decade, if not longer, for scientists to establish a conclusive link between a greater greenhouse effect and global warming. In the meantime, the buildup of greenhouse gases can be slowed through measures such as reforestation, energy conservation, the use of less polluting fuels like natural gas and the devel- opment of alternative energy sources. These will not only improve the chances of dealing with the risk of global warming but will also pay dividends in many other ways - providing cleaner air and water, reducing acid rain, conserving resources, preserving the ozone layer and making ecosystems healthier. 30 tid rain A study of the effects of acid Tain offers many examples of the complex linkages among different parts of the en- vironment. It also shows how human activities in one place can have consequences in another, perhaps hun- dreds or thousands of kilometres away. In the case of acid rain, the chain of events begins with the release of acid gases from thermal power stations, smelters and cars and ends with the destruction of fish and other forms of lake life, often in environments far from obvi- ous centres of pollution. Acid rain was first described in the 1850s by a British scientist in England's industrial Midlands, but it was not considered a serious problem until a century later when fish populations began to decline in lakes in Europe and eastern North America. In Ontario, lake acidification was first reported in the early 1960s, in the Sudbury area. A few years later, researchers from the University of Toronto noticed that lake water had acidi- fied and fish populations had declined in Killarney Park on the northeast corner of Georgian Bay. During the 1970s, lake acidification was reported in other parts of central and northern Ontario, notably in the Muskoka- Halîburton cottage country. Subsequent research demonstrated that there were links between emissions of acid gases, rainwater chemistry, lake acidification and effects on lake life. It was not until the mid- 1980s, however, that Cana- dian Ontario and U.S. governments began to develop co-ordinated policies for controlling acid rain. The problem has been complicated by the fact that these gases can travel long distances, crossing provincial and international borders as they are carried along by atmos- pheric currents. Much of the acid rain affecting southern Ontario comes from the United States. Similarly, much of the acid rain affecting the eastern states and provinces originates in Ontario. Solving the problem has therefore required close co-operation between governments. In spite of these difficulties, however, important progress has been made. SOME HiCKOCHTS PROM THIS 5S.CTIOK An estimated 19,000 of the total 250,000 lakes in Ontario are acidic enough to cause damage to species living in them. In Ontario, emissions of sulphur dioxide (the major cause of acîd rain} have declined by more than 70 per cent since 1970. Areas of high sulphate deposition (more than 20 kg per hectare a year} have also declined. Some lakes are recovering from acidification. One study of 38 Sudbury-area lakes reported a substantial decline in acidity in the 1980s. Decreasing acidity and the recoveryof fish populations have been reported in some otherlakes. There is, as yet, there is no evidence of recovery for lakes in central Ontario. 31 acid rain continued Figure 6.1: Caïaotï to tseutrauze acid ©EPOsmoN I low I median high organic Chapter 6 how acid rain affects the environment What is add rarn? Pure rainwater, even in unpolluted areas of the world, is usually slightly acidic. Acid rain, formed from acidifying pollutants in the air, is substantially more so. Acidity is measured on the pH scale. A pH of in- dicates maximum acidity, 14 represents maximum alka- linity, and 7 is neutral. Each full point on the scale repre- sents a tenfold change in acidity. Normal, slightly acidic rainwater has a pH somewhere between 5.0 and 5.6. But during the 1980s, the average pH of rainfall over central Ontario was 4.2, or about ten times more acidic than normal rainwater. Acid rain gets its acidity from two air pollutants, sulphur dioxide (SO2) and nitrogen oxides (NO x ), which react with water in the air to produce sulphuric and nitric acids. In Ontario, sulphur dioxide comes mainly from the burning of sulphur-containing coal to produce electricity and from the smelting of sulphur- containing ores. Nitrogen oxides are produced during combustion. Various means of transportation, taken to- gether, add up to the largest source of nitrogen oxides in the province, accounting for about 60 per cent of emis- sions. Motor vehicles produce more than two thirds of those emissions. The acids reach the earth's surface in two ways. One is through wet deposition, in which the pollutants are washed out of the air by precipitation - not only the fa- miliar acid rain but acid snow, fog, and hail as well The other is dry deposition, in which acid gases or particles in the air reach the earth directly. Acid deposition, the preferred scientific term for acid rain, encompasses both of these possibilities. Because acid pollutants can travel hundreds of kilo- metres before being deposited, Ontario is exposed not only to its own acid emissions but also to those from ad- jacent industrial areas of the United States. These U.S. emissions are carried by weather systems moving in a northeasterly direction and account for about 50 per cent of the sulphuric acid deposited in the province. In Ontario, acid deposits formed from sulphur dioxide have had a much greater impact on the environ- ment so far than those formed from nitrogen oxides. One reason is that there are far more sulphur dioxide emissions - nearly 1,000,000 tonnes per year as com- pared to less than 500,000 tonnes a year for nitrogen ox- ides. Another is that the nitrate from nitric acid is used rapidly as a nutrient by plants during the growing sea- 32 acid rain continued son. It is usually only in the spring, after the ground has been frozen and plants have been dormant for several months, that nitrate shows up to any significant extent in surface runoff. Consequently, the battle against acid rain has been fought largely on the sulphur dioxide front What araas «r« attested? Some parts of Ontario receive more acid rain than others, but some areas also have natural characteristics that help to protect them against acidification. The greatest amount of acid rain in the province, for exam- ple, falls in the southwest, yet the area has no acidic lakes or rivers. The reason lies in geology. Most of southern Ontario has limestone bedrock underlying it In these limestone regions, soils and water have a strong capacity to neutralize the acid deposition falling on them - much like antacids that neutralize stomach acidity. These are the areas of high neutralizing capacity shown in Figure 6.1. Soils and water in areas of underlying granite bedrock, however, have very little neutralizing capacity. These are the areas shown as low in Figure 6.1., and they include the Canadian Shield as well as the Muskoka, Haliburton, Parry Sound, and Nipissing cottage country of south-central Ontario. Under unpolluted conditions, the pH levels of lakes in these areas would lie somewhere between 6 and a little more than 7; however, today many are between 5 and 6. Smaller lakes have been found to be particularly susceptible to acidification. Some of these sensitive areas, such as the cottage country of south-central Ontario, are exposed primarily to acid pollutants originating in the United States. Oth- ers, such as the Sudbury area, receive most of their acid pollutants from local sources. Figure 62i Lake suiphaie / J <2.Q 11 2.0-4.0 : iii 4.0 - 6.0 J 8.0-8.0 iB 8.0 - 10.0 W- 10.0 + .&*; ' Se; :a.\ In softwater lakes, high concentrations of sulphate indicate exposure to acid pollutants formed from sul- phur. (In hardwater areas, sulphate may already be pre- sent from natural sources.) Thus, in Figure 6.2, lakes in the northwest show the low sulphate concentrations typical of unpolluted lakes on the Shield. Lakes farther east, however, show extremely high concentrations of sulphate, even though no natural sources are present These areas of high sulphate concentration correspond closely to the areas of low pH (high acidity) in Figure 6.3. The most severe acidification is apparent in lakes in the Sudbury area. 33 acid rain continued Figure 63; Lake pH 4.5-5.5 5.5 • 6.5 6.5-7.5 >7.5 -www ,^v.w.-.,.;, V>,'Ai' "if *■ ?/t__ «fS^te^ /j jsS < Figure 6.4: Plankton diversity and lake aodîty (number of phytopiankton genera and zoopUnkton species in lakes with pH less than 6.5) pH "30~ as 20 ■j's id "~5~ "o" I hfcjnber 35 kg/h8/yr not S04 ♦ >5D ppb dayGght BS 03 Mod- >25kg/ha/yrwacS04 » *30 pp6 Height. GS 03 Low - <2D kg/he/yr wet S04 » <2Q pot daylight GS OS Mean of all trees > 10cm dDh Studies in Ontario forests showing signs of environ- mental stress revealed that extreme climate stress, defoli- ation by tent caterpillar, and infection by root diseases were the main causes of the decline. At some of these sites, where the soil was very acid- sensitive, high alu- minum concentrations were detected in the soil and roots of affected trees. Studies show that aluminum might block the plants' intake of nutrients. This is consistent with what we know about the ef- fects of acid rain on forests. The impact of acid rain is not always obvious, as the trees appear to die of natural causes. But, acid deposition might affect a plant's ability to absorb nutrients. As the soil acidifies, natural decom- position slows down, reducing nutrient recycling. Poten- tially toxic metals such as aluminum may change form, inhibiting root growth and interfering with a plant's ab- sorption of nutrients. The trees become weaker and sub- sequently more susceptible to environmental stress and insects and diseases. Although the effects on forests in those acid-sensi- tive areas was mainly due to natural causes.the evidence suggested that acidic deposition, contributed to the decline. Figure 6.7 illustrates the trend in sugar maple growth rates across the province. In areas where acid de- position is greatest, the growth rate has declined about 27 per cent relative to the rate of tree growth in the early part of the century. Although it cannot be concluded with certainty that this growth reduction is caused by acidic deposition, research has shown that air pollution is a stress on the forest ecosystem. In 1986, Ontario began a seven-year survey of the health of hardwood forests, tracking tree decline across the province. Overall, tree condition was considered to be good to very good, although significant decline was observed in the Espanola, Parry Sound, and Minden ar- eas. Tree decline has persisted in these same three areas. Based on results from this province-wide survey, tree decline in the hardwood forest ecosystem of Ontario is not considered a significant problem, although isolated, persistent, pockets of decline exist. Human and animal health The direct effects on human health of sulphur diox- ide and nitrogen oxides in the air were noted in chapter 2, but the effects of acidified lakes and soils on human and animal health are less dear. One possibility is that birds and animals that feed on fish, crustaceans and oth- er endangered forms of aquatic life will find it more dif- ficult to survive because their food supply has decreased. Another is that some birds and animals, as well as humans, will be exposed to higher levels of toxic metal- lic compounds that may cause cancers, mutations, or re- productive failure. High acidity increases the rate at which toxic metals are leached from soils and rocks into the water and also encourages the formation of toxic compounds of these metals. These substances may then accumulate in the food chain, where they would be par- ticularly harmful to fish-eating predators, including hu- mans. Studies at a number of acid lakes in the province have shown that fish -eating waterfowl, such as the Com- mon Loon, produce fewer young as the supply offish decreases. On the other hand, some insect-eating water- fowl, like Common Goldeneyes, which compete for the same food supply, actually prefer Ashless lakes. Erosion of buildings Acidic air pollution eats away at many kinds of building materials. Limestone and marble are particu- larly vulnerable to damage by sulphur dioxide and sul- phuric acid because of chemical reactions that cause these materials to expand and crack Acid pollutants are at least partially responsible for an increase in the decay of historic buildings in Ontario. icid rain continued Chapter 7 Acid rain: are we making progress? Cantr-oiiing acid rain Efforts have been under way since 1970 to control emissions of acid gases, both to reduce local pollution from sulphur dioxide and nitrogen oxides and to mini- mize acid deposition. During the mid-1980s, Ontario set two important control targets. One was to reduce the rate of sulphate deposition in sensitive areas to less than 20 kg per hectare a year. The other - needed to achieve the first - was to cut sulphur dioxide emissions to one half of the 1980 level, by the end of 1994 (885,000 tonnes of sul- phur dioxide a year). Targets were set for Ontario's largest emitters: Ontario Hydro's thermoelectric power plants, the large smelters belonging to Inco and Falcon- bridge in the Sudbury area, and Algoma Steel's sintering plant in Wawa. Inco expects to reduce its sulphur diox- ide emissions to 265,000 tonnes annually by 1994. In the late 1960s, before controls were implemented, Inco emitted nearly 2,000,000 tonnes of sulphur dioxide a year. Because acidic air pollutants are transported into Canada from the United States, American control mea- sures are also critical to our success in reducing acid de- position. Amendments to the U.S. Clean Air Act, adopt- ed in 1990, have set sulphur dioxide emission limits for 37 acid rain continued Figure 7.1: Wet sulphate deposition 1981-83 Kilograms/hectare 4 II 10-20 ::|] J 20-30 J 30-40 II 40 + Figure 7. 1: Wet sulphate deposition 1984-86 m "^^"%- ' ■■*■ ,>*$?■> KBograrns/hactare 1 10-20 J 20-3Q J 30-40 Hi 40 + Figure 7. i : wet sulphate deposition 1987-89 Kilograms/hectare !i 10-20 M 20-30 J 30-40 m il 40 + specific electric power generating stations. These limits should reduce annual emissions in the United States by 4.5 million tonnes by 1995 and by an additional 4.5 mil- lion tonnes by the year 2000. Because nitrogen oxides have been the lesser con- tributor to acid deposition, efforts to control them have not been as vigorous. Over the past two decades the most important NOx controls have been the use of cat- alytic converters in motor vehicle exhaust systems and the trend towards more fuel-efficient cars. Ontario's cur- rent position is that emissions of nitrogen oxides should be held to 1987 levels, although that target could change as more scientific information on the effects of nitrogen oxides becomes available. What progress hm> been vkkIh? As shown previously in chapter 2 (figure 2. 1), annual emissions of sulphur dioxide in Ontario have fallen by more than 70 per cent since 1970. In 1992, they totalled about 900,000 tonnes. The province is therefore well on track towards meeting its emission target for 1994. Tighter emission controls and improved produc- tion technology in metal smelters account for the major portion of these reductions. Conversion to low-sulphur fuels has also brought about large reductions in emis- sions from thermal power generating stations. Emissions of nitrogen oxides have also decreased, though less dramatically. As shown in chapter 2 (figure 2.4), emissions remained fairly constant between 1983 and 1989, then declined by more than 10 per cent be- tween 1989 and 1991. These reductions were primarily the result of lower emissions from vehicle exhaust and electricity production. As the number of motor vehicles on the road continues to rise, the level of nitrogen oxide emissions may change. The decline in emissions of sulphur dioxide has been accompanied by a definite improvement in the amount of acidic material deposited. This can be seen in Figure 7. 1 , which summarizes data from a network of monitoring stations that has been tracking acid deposi- tion since 1979. Very high levels of sulphate deposition are evident in the early 1980s, especially in southern and southwestern Ontario. By the late 1980s, the very high deposition areas had virtually disappeared and the areas of lower deposition had increased markedly. It remains to be seen, however, if affected systems will recover when the rate of sulphate deposition is within the con- trol target of 20 kg per hectare a year or if lower levels of sulphate deposition are required to protect sensitive lakes. Ultimately, the response of the environment will telL Repairing Che damage Can acidified lakes and their biological communi- ties be returned to their normal, healthy state? There is good evidence that they can. Figure 7.2 shows trends in pH and acid-neutralizing capacity for a set of 38 lakes in the Sudbury area. Acid-neutralizing capacity is a mea- sure of the amount of acid a lake can still neutralize. If a lake can no longer neutralize acid, its neutralizing ca- pacity is negative and it is an acid lake. As the graph shows, both the pH and the neutralizing capacity of these lakes have increased. Clearly, lakes in the Sudbury area are recovering from their severe acidification. acid rain continued FlGURB 7.2; ? H ANJ> ACiI>-NBVTRAUZfNG CA?ACtTT Of 38 UKES IN the Sudbury area 6 -ass 3 • pH 4.5 5X1 5.5 60 6.5 7.0 7-5 80 B.5 FfGUftE 73: PH AND AClD-NEUTRAliZi !*î CAPACITY OF TWO LAKES IN THE MuSKOKA-HaIJBOSTON AREA LakepH 8.0 ■; Harp Lake Î1 Plastic Lake 75 '76 '77 '78 '79 80 -81 'SE '83 -84 '85 "86 "87 B8 -89 '90 '91 3S acid rain continued A survey of 54 lakes in the Algoma region has also reported some rapid recoveries. Two lakes that had pH levels below 5.5 and were Ashless in 1979 have recovered to the point where it has been possible to re-establish their fish populations. Farther south, in the Muskoka-Haliburton area, the trends are more ambiguous. Figure 7.3 shows data from two intensively studied lakes in that area. While it seems safe to say that the lakes are not getting worse, it is not clear that they are recovering significantly from their acidification. However, most of the acid deposition in this area originates in the United States and the full im- pact of American reductions in sulphur dioxide emis- sions has yet to be felt. Overall, the prospects for controlling acid emissions and recovering from their effects are very good. But this does not mean that the book on acid rain can now be closed. It still remains to be seen if most of the affected lakes and their ecosystems return to normal or whether further controls are required. Still, evidence suggests that a potentially large ecological disaster has been ar- rested. Ontario has a generous share of the world's water re- sources. It has more than 250,000 freshwater lakes, un- counted rivers and streams and a 5*300-km shoreline on four of the five Great Lakes. The Great lakes alone, counting both the Canadian and American portions contain 20 per cent of the world's surface freshwater supply. Water is also extremely useful as a means of trans- portation, an industrial raw material, a source of energy, a sewage disposal system and a medium of recreation. Unfortunately these uses often diminish its capacity to support life and, in some cases, may even make it dan- gerous to the life forms that depend on it Water quality varies from place to place and to some extent depends on local geological conditions. But as a result of human activities, water is exposed to pollu- tants that can harm aquatic plants and animals and make it unfit for recreation, drinking, irrigation, or oth- er uses. Surface waters are exposed to pollution from point sources such as municipal and industrial waste discharges, from non-point sources such as urban and agricultural land use, and from airborne pollutants that may have originated several hundreds or thousands of kilometres away. Groundwater, though fess susceptible to contamination, may also pick up contaminants from landfills, storage tanks, firm fields and other surface sources. These pollutants may still be carried by the groundwater when it eventually returns to the surface to replenish rivers and streams. Pollutants, however, are not the only problem. Wa- terways may also be modified physically through the building of dams and artificial ponds, dredging, modifi- cation of channels and stream diversions. All these activ- ities can have a impact on habitat and water quality and can disrupt an aquatic ecosystems. This section looks at the issues affecting the main water groupings in Ontario - inland waters, the Great Lakes and groundwater - and concludes with an assess- ment of water quality as it affects human health. Chapter 8 Inland surface waters Ontario's inland waters flow through some of the world's most pristine wilderness and some of its most intensively industrialized urban areas. The quality of these waters varies enormously from one part of the province to another. Figure 8.1: DisTRiBirnoN of economic AcrrvTr? with POTENTIAL TO AFFECT SUREAŒ WATER QUALITY Economic activités „J Agriculture _J Urbanization ËI Mining/smelting / V _j Power dams "v-~il Pulp S. paper / !f Residential development /" iili Residential development \ {secondary issue] Note; map based on data collected as part of Provincial Water Quality MonitorisigNetwotfc (1990-93) and Inland Lakes (1986-90) .....1 41 water continued Water quality in inland waters across the n orth is generally good except fer sensitive areas exposed to acid tain and the local effects of pulp and paper mills, mining, and forestry. However, problems of nutrient enrichment, turbidity and bacterial contamination are w jdespread in inland rivets and lakes across southern Ontario, largely as a result of urban and agricultural land use. Consumption restrictions for larger sizes of some sport fish are fairly common across central and northern Ontario. Most of these are partial rather than total restrictions, al- though women of chfldbearmg age and children under Î5 should not eat fish in any of the restricted categories- Mer- cury contamination, from both natural and human sources, is the most common reason for consumption advisories. Problems of algae growth in Lakes Erie and Ontario have diminished considerably during the past two decades but have not been eliminated, in the western basin of Lake Erie, loadings of phosphorus {the nutrient largely responsible for the problem} have fallen from about 20,000 tonnes per year in the J960s to between 5,000 and 6,000 tonnes per year in the late 1980s. The human impact on surface waters comes from a number of sources, including urbanization and residen- tial development, farming, recreational activities, dams, mining and smelting, pulp and paper operations and forestry. Figure 8. 1 shows how these are distributed across the province. In southern Ontario, agriculture is a key cause of poor water quality in the area's rivers and lakes. Valuable wildlife habitat can be destroyed through drainage of wetlands, the straightening or destruction of river banks and streamflow alterations. The use of tue drainage in fields lowers the water table, while the clearing of forest cover from stream and river banks increases exposure to sunlight and raises water temperatures. In addition, Water quality is generally good in the open waters of the Great Lakes, but localized problems exist throughout the basin. Concentrations of PCBs and other toxic substances in the Great Lakes, as measured in the tissues of fish, have dropped substantially since 1 975, although the rate of de- crease has levelled off ift recent years. .Excessive concentra- tions are stiB measured in some localities. : It is estimated that there are more than 500,000 water wells în Ontario. On average, the ministry receives about one complaint about groundwater quality or quantity per year for every 250 wells. A survey of well water from 1 300 Ontario farms showed that 37 per cent contained concentrations of contaminants in excess of the provincial drinking water objectives. Drinking water from municipal water supplies is very safe. Between 1985 and 1992, more than 165,000 analyses were carried out on drinking water samples from more than 100 munkipaSties. Only 66 instances of exceeding the drinking water objectives were reported. streams flowing through intensively farmed areas often pick up large quantities of soil particles, fertilizers, pesti- cides, cattle manure and other wastes, leading to prob- lems of turbidity, nutrient enrichment, toxic and bacter- ial contamination and oxygen depletion. Urbanization, is another significant cause of poor water quality in the heavily populated areas of the south. Cities and towns produce enormous quantities of indus- trial wastes and municipal sewage that are often high in nutrients, oxygen-depleting material, solids and bacte- ria. The paved streets and compact soils of urban areas also decrease the absorption of stormwater, lowering the water table and increasing surface runoff. As well as al- tering levels and flow rate of rivers and streams, runoff ns. washes substantial quantities of dirt, oil, garbage, road salts and other urban debris into adjacent water bodies. In addition, wetland drainage and the straightening or destruction of river banks destroy important aquatic habitats. Because farms and cities are spread throughout most of southern Ontario, water quality problems from agriculture and urbanization are widespread. In the north, on the other hand, problems tend to be more lo- calized and connected with point sources of pollution such as mines, smelters, and pulp and paper mills, al- though the effects of recreational activities and airborne pollutants such as mercury and acid gases are spread over a wider area. Hydro dams also may have local im- pacts on some northern rivers, causing fluctuations in water levels that can destroy habitat for fish and other aquatic life. In addition, urban centres in the north, es- pecially the larger ones such as Sudbury, Thunder Bay and Sault Ste. Marie, can have much the same kind of impact on local watersheds as their counterparts in the south. The quality of Ontario's inland waters is monitored at some 700 sampling stations. Samples collected at these sites are a useful source of information about many aspects of water quality and the stresses affecting it, particularly in southern Ontario. Phosphorus and nitrogen are important nutrients. Too rich a supply of these substances, though, can over- stimulate the growth of phytoplankton (algae) and other aquatic plants, to the detriment of fish and other water life. Large blooms of algae are the most visible evidence that rivers and lakes are receiving an overabundance of nutrients. From a human point of view, algal blooms are water continued RGURg 82: TOTAt PHOSPHORUS CONCEifrRATTONS m SURFACE WXTESS Median concentrations fmilligrams/Btrel J 0.00 -0.01 il 0.01-0.03 J 0.03 -0.10 Il 0.1O + Note: map based on data colfccted as part of Pnwïnciaï Water Quality MonitoringNetwork (I99Q-93) and Inland Lake* (IS86-90) an aesthetic nuisance that create unpleasant odours or destroy the charms of a favourite swimming spot But to fish and other water life, they can be fatal. When the al- gae die off, their decay may use up much of the water's dissolved oxygen. If too much oxygen is depleted, fish and other aquatic animals may die. In Ontario, many rivers and lakes receive an over- supply of nutrients from agricultural fertilizers that have been washed off farmers' fields by rainwater. Besides be- ing used in fertilizers, phosphorus and nitrogen com- pounds are found in industrial chemicals and in a large 43 water continued assortment of everyday products, including detergents, household cleaners, motor lubricants and food. Conse- quently, phosphorus and nitrogen show up in substan- tial amounts in effluent from municipal sewage systems, rainwater runoff from city lawns and streets, and dis- charges from pulp and paper mills, food processing plants, chemical factories and other industrial sources. Figures 8.2 and 8.3 show median concentrations of phosphorus and nitrates (a form of nitrogen) in surface waters in various parts of Ontario. (The median or mid- range value is the value halfway between the highest and lowest readings obtained.) These maps are based on measurements taken between 1986 and 1993. According to ministry guidelines, excessive plant growth in rivers RGUR£ 8.3rNrniATECONŒOTRAnClNS IN SURFACE WATERS Median concentration Wj \ Imilîtarams/lître) //- ^}r" Ci] m 2.5 - 5. D i \ ;'■■ Note; map based on data, collected a& part of ProWnciaJ Water QoaKty Monitoring Network (1990-93} and Inland Lakes {1986-90) and streams is unlikely to occur if the total phosphorus concentration is below 0.03 milligrams per litre. In lakes, the guideline value for nuisance growths of algae is slightly lower. A similar guideline is not yet available for nitrate, but natural concentrations in surface waters are rarely greater than 0.5 milligrams per litre. As the maps in Figures 8.2 and 8.3 show, both phos- phorus and nitrate concentrations are exceptionally high in the farming counties of the southwest Many of the water bodies in this area are now degraded by excessive algae growth. The Fanshawe and Gordon Pittock reser- voirs on the Thames River provide good illustrations of the impacts. Both of these popular recreational areas have been closed to the public at times and have had fish die because of nutrient enrichment and algae growth. Phosphorus levels are also high in other farming ar- eas - particularly around the eastern end of Lake On- tario and in the southeast between the Ottawa and St Lawrence rivers. In addition, phosphorus concentrations above the guideline value are found in scattered loca- tions in northern Ontario, where they may be a result of industrial discharges, municipal sewage, or local geolog- ical conditions. Also, oxygen in the water can be used up by the de- cay of organic matter in waste water or the oxidation of chemicals such as ammonia. These substances are known as biochemical or chemical oxygen-demanding materials (BOD and COD, for short). Municipal sewage treatment plants and industries that produce large amounts of organic or chemical waste - pulp and paper manufacturing, food processing, iron and steel produc- tion and petroleum refining, for example - are common sources of oxygen-depleting materials. Figure SA: Faecal coliform densities in surface warns Counts/100 rriMitres :V>.7 V ^. _J 0.0-100 100-1000 1000 + Bacteria A century ago, bacteria in drinking water caused large numbers of deaths from diseases such as typhoid and cholera. Thanks to improved sewage disposal prac- tices and routine treatment of drinking water, municipal water supplies are now safe. Bacterial contamination re- mains a common water quality problem and causes the closure of many swimming areas every year. Rural water- courses are com- monly polluted by wastes from cattle that are watered in streams, by the dumping of milk- house wastes, by leakage from septic tanks and by ma- nure spread on fields. In urban ar- eas, sewage treat- ment plants and sewer overflows during heavy rains are common sources, as are some industrial fa- cilities such as food processing plants and pulp and pa- per mills. The most common indicator of bacterial cont- amination in water is the presence of elevated densities of faecal coliforms or E. coli bacteria. Water with an average faecal coliform density of more than 100 counts per 100 m I. in a series of water samples is considered unsafe for swimming or other water continued recreational uses that involve bodily contact with the water. As Figure 8.4 shows, levels in excess of this guide- line are reached in many parts of southern Ontario, es- pecially in and downstream of farming areas. In some urban areas, temporary increases in bacterial levels often follow heavy rainstorms, because the sewage system can- not handle the extra flow and raw sewage is discharged directly to the receiving waters to avoid backups and overflows in the sys- tem. ,£>' Note: map based on data collected as part of PiovinâalWater Quality Monitoring Network (1990-93} and Inland Lakes (1986-90} Tufbkftty Turbidity is a measure of the scattering of light in water. Essentially, it is a measure of water clarity (or, more precisely, the lack of it), and it is a good indication of the amount of suspended solids that water contains. Many of these solids, such as mi- cro-organisms, minerals and fine particles of clay, are of natural origin, but a number of human ac- tivities add large quanti- ties of suspended solids to nearby water bodies. The effluent from pulp and pa- per mills, for example, contains large amounts of wood fibre. But apart from industrial effluent, much of the ex- tra loading of suspended solids comes from urban and agricultural runoff, from forestry activities such as clear- cutting, and from damage to river banks by construction and cattle. 45 water continued Too high a concentration of suspended solids may make water unsuitable for recreational and other uses and can have devastating effects on the aquatic environ- ment, smothering bottom-dwelling organisms, ruining spawning grounds, reducing the amount of sunlight reaching plants and phytoplankton and even plugging the gills of fish. Suspended particles also provide a bonding surface for toxic Figure 8.5 shows that the highest levels of turbidity are found in the highly urbanized watersheds around Lake Ontario and in the farming country of the south- west. Turbidity levels on the Shield are much lower, al- though forestry, mining, and pulp and paper manufac- turing can have local effects. ¥, -Vît' v- metals and chemicals. In agricultural areas, turbidity problems have been common for years. To a considerable extent, they are the result of the clearing of forests and drainage of wetlands by the first few generations of agricultural settlers in the nineteenth century. Still, new problems con- tinue to arise. In the early 1980s, for example, the clear blue waters of Little Lake at Barrow Bay on the Bruce Peninsula were turned brown and murky by sediments released from the clearing of agri- cultural drainage ditches. This work also resulted in the loss of a brook trout stream, while cattle access to the ditches and runoff from fields continued to contribute bacteria, chemicals and additional sediments to water flowing into the lake. Some remedial action has been undertaken since then, but a number of water quality problems remain. FiGlfRS 8.5: MEDIAN TURBTDlTf OF SURÏACT WATERS /eft/* ?^v. For»na2Hvti8"bicfity uruts v "rfvA----r-, J 0-5 ^ } U J I J 5-10 •' Ï-' T'.._J J 10-50 II 50 + SA* C.J'-b i~c^ Physle«î »np3C£s Many of Ontario's rivers have been dammed to control flooding or to pro- vide water for power generation. Hundreds of streams were also dammed in the nineteenth century to provide water for grist mills and many of these dams still survive. Dams and the ponds behind them have a num- ber of disruptive effects on aquatic ecosystems. Among other things, they may destroy habitat, isolate fish from their spawning grounds, deplete oxygen, alter water temperatures and increase evaporation from the watershed. They also contribute to the release of toxic metals from newly flooded areas, particularly mercury, which can accumulate to high levels in fish from reser- voirs. Note: map based on data collected as part of Provincial Water Quality Monitoring Network { 1990-93) and Xnland Lakes ( 5986-90) ;S Water level fluctuations caused by the operation of a hydroelectric dam on northern Ontario's Nipigon Riv- er, for example, have contributed to the decline of the river's brook trout population, mainly because of dam- age to the fish's spawning grounds. In other parts of the province, flow alterations have been caused by a variety of factors, including stormwater systems, field drainage, the elimination of wetlands and the increased impervi- ousness of the ground in many watersheds (as a result of paving, for example, or the compacting of soils by heavy machinery). Other common physical stresses on waterways in- clude dredging, deforestation, boat wakes, and shoreline alterations such as the straightening of river banks. These can be very destructive of aquatic habitat and can greatly increase turbidity. Flow alterations and habitat destruction are major causes of water quality impair- ment in many of the province's aquatic systems. Persis&îfit toxic substances Toxk substances interfere with important biochem- ical processes in living organisms. There are many dif- ferent types of toxic substances, but of particular envi- ronmental concern are those (such as mercury, lead and other heavy metals) that cannot be broken down into less harmful substances, or those (organochlorine com- pounds such as PCBs and dioxins) that do so very slow- ly. Many of these substances also accumulate readily in living tissue. These are known as persistent bioaccumu- lative substances and organisms can eventually build up harmful concentrations of them in their systems, even when levels in the surrounding environment are barely detectable. While the individual effects of each substance vary, long term exposure to these substances has been linked water continued to cancer, reproductive failure, birth defects, genetic mutations, organ damage and/or damage to the nervous system in both humans and wildlife. The most common persistent toxic substance found in inland lakes is mer- cury. Several persistent toxic substances exist in nature, but a number of them are also widely used in manufac- turing and found in an extensive variety of ordinary, everyday products. As a result, many of these substances enter rivers and lakes from municipal sewage systems, industrial discharges, rainwater runoff and the air. In farming areas, pesticides and herbicides are the most common source of these contaminants. In northern On- tario, pulp and paper mills, mines and smelters are the most conspicuous sources. Because persistent toxics can be passed up the food chain from prey to predator, concentrations can become extremely high in fish. Thus, for humans and other top predators such as mammals and waterfowl, the most im- portant pathway of exposure to these substances is not water but fish. Because of the potential health risk from eating contaminated fish, sport fish in Ontario's lakes and rivers have been regularly sampled and tested for toxic substances for a number of years. Consumption advisories are issued for those lakes and rivers where contaminated fish have been found. Consumption advisories depend not only on loca- tion but also on the species and size of the fish. The larg- er and older the fish, the higher the toxic concentrations are likely to be. Figure 8.6 shows where consumption advisories have been issued for 45-55 cm walleye, a warm-water species that is well distributed throughout the province. Figure 8.7 shows where advisories have been issued for 35-45 cm lake trout, a representative cold-water species. 47 water continued Figure 8.6: Inland lake HsucoNSUMFnoN advisories FOR 45-55 CM waOEïï Advisories ^ Unrestricted consumption \ j Restricted ccmsumption "-••• % Total conswnption restriction J&.V .- *;:%-- For both species, total consumption restrictions are relatively few, but partial restrictions are widespread. Mercury is by far the most common contaminant for which these restrictions have been issued. Because the industrial use of mercury has declined considerably since the 1970s, a consumption advisory does not neces- sarily indicate that there is a current human source of mercury contamination in the area. The mercury in the fish may also have come from natural sources, residues of past episodes of contamination, disturbance of the watershed (e.g., flooding), or airborne deposits from other areas. According to ministry studies, most of the mercury entering remote Shield lakes comes from the air and about half of this amount comes from human sources. One of the worst cases of mercury pollution in On- tario occurred during the 1960s and early 1970s when discharges from a chlor-alkali plant at Dryden severely contaminated the English-Wabigoon river system. With mercury levels in fish running as high as 12.0 mg/kg, sport and commercial fishing on the river had to be closed. Mercury levels in the English-Wabigoon system de- clined considerably during the 1970s and early 1980s as a result of discharge controls and the eventual closing of the plant. Levels have remained relatively stable since 1983, but some mercury still remains in the system. Four lakes in the area have been monitored regularly since 1970, and mercury levels in walleye from one of them (Clay Lake) still average more than 2.0 mg/kg. Mercury levels in uncontaminated fish are generally less than 0.5 mg/kg. Elevated mercury levels have also been found in Lake Abitibi, the Mattagami River, the Ottawa River and lakes in the Huntsville area. High levels of chlorinated organic compounds are relatively uncommon in sport fish from Ontario's inland waters. Significant levels of PCBs, for example, have been detected in sport fish at only two inland locations - in Lake Clear near Renfrew and in the Otonabee River and Rice Lake near Peterborough. The PCBs in Lake Clear have been traced to the use of contaminated mate- rials for oiling nearby roads in the mid-1970s. Cleanup of the lake has now been completed and monitoring is under way to determine if more work is needed. PCBs in the Otonabee River and Rice Lake have been found only in bottom-feeding fish such as carp and levels have been below the federal guideline of 2.0 ppm for the sale of commercial fish. The source has been traced to contaminated wastes that were discharged into Peterborough's sewer system over a number of years by two local industries. The industries have co-operated in cleanup efforts, but the sewer system still appears to be saturated with PCBs, which are discharged into the lake and river after heavy rains. A committee is now looking into further ways of dealing with the problem. water continued Figure 8.7: Inland lake rsh consumption advisories PC* 55-45 CM UX£ TROVT y'\ Advisories V <§j Itorestricted consumption Js- Restricted consumption / 1&* Total consumption restriction PrciteiAsng inland waters To improve inland water quality, both point and area sources of impairment must be tackled. Controls on point sources have been evolving since the mid- 1960s when the Ontario Water Resources Commission began setting objectives for the discharge of a number of industrial water pollutants. These and other initiatives have already significantly reduced loadings of some pol- lutants in a number of areas. Figure 8.8, for example, shows how phosphorus concentrations in the Credit River declined in the 1970s as a result of legislation re- ducing the phosphate content of laundry detergents and again in the 1980s as a result of the introduction of phosphorus treatment at an upstream sewage plant. Regulations being developed under Ontario's Mu- nicipal Industrial Strategy for Abatement (MISA) are ex- pected to bring further reductions in pollution dis- charges from both industrial sources and municipal sewage treatment plants. Regulations for the pulp and paper industry, released in November 1993, for example, will reduce the discharge limit for chlorinated com- pounds by 68 per cent by the end of 1999. Reductions of point-source pollution will benefit a number of water systems, particularly in the north where most water quality problems are related to point- source impacts. In the south, however, agricultural activ- ities have a much greater and more widespread effect on water quality than either municipal or industrial sources. §ar ^ •• • \ FK5Ur£;8.8; PHOSPHORUS CONCENTRATIONS IN THE WEST BRANCH OF THE CREDIT RIVER DOWNSTREAM OF A SEWAGE TREATMENT PLANT Phosphorus Concentration (miBigrams/litre) 1.2 To"" t : 0.8 0.6 04 : : 0.2 \ H ill! lln . ! .) . ^otoNcomOT- cu < o) o> 0) O) © oj ./ '••-;. '•— .~~y the worse than for the better. Several increases in faecal coliform densities have occurred in the greater Toronto area, mainly as a result of urban development (Figure 8.11). Increases in the Muskoka, Haliburton, and Kawartha Lakes regions probably result from more in- tensive cottage development and recreational activity. Increases in turbidity are most noticeable in the Grand River watershed and in cottage country (Figure 8. 12). Once again, residential development is the most likely cause. In general, then, these measures of surface water quality, except for phosphorus, have improved little since the 1970s and in some areas there is evidence of continuing deterioration. Surface waters throughout 51 water continued Ficms. 8.12: Changes in tcrbidity concentration en aSAJ© tAKES 1975-76 TO 1990-93 %trf sites #j increasing concentration 23 ^ fcio significant change 75 @? Decreasing concentration 2 rrumber of sites: 337 •-**>- «»..* > / . "-lit;, '-'-'^wh southern Ontario are generally less than satisfactory in terms of their suitability for recreation, aesthetic quali- ties and ability to support all the fish and plant popula- tions that they once did. The poorest water quality is found in the southwest, in the Golden Horseshoe around the western end of Lake Ontario, and along the Rideau and lower Ottawa rivers. On the other hand, water quality impairment in northern Ontario is generally much less widespread. Ex- cept for localized impacts from resource industries and urbanization and for those areas affected by acid rain and recreational activity, water quality in many northern lakes and rivers remains close to its natural state. Most of the initiatives for improving surface water quality are fairly recent in origin and although some of them have begun to produce results, for the most part little improvement has been seen yet It may take some time before significant results are achieved. Chapter 9 The Great Lakes The Great Lakes are one of the world's most important freshwater resources but, set within the economic heart- land of North America, they also are subject to intensive pressure from human activities. More than 35 million people live in the Great Lakes basin and more than nine million of those live in Ontario. About 17 per cent of the United States' manufacturing capacity is located here, along with about 45 per cent of Canada's. Some 2.5 tril- lion litres per day of water are withdrawn for industrial, domestic and agricultural uses as well as for power gen- eration and sanitation. In addition, the lakes serve as a highway for ships from around the world and as a playground for recre- ational purposes. They also provide habitat for aquatic life and support a large commercial and sport fishery. In 1990 the commercial fishery alone landed 24.5 million kilograms offish, with a dockside value of $42 million. In such an environment, the lakes are exposed to pollution from many sources, including discharges from industries and municipal sewage systems, spills from ships and runoff from adjacent fields and city streets. In addition, groundwater and rivers flowing into the lakes bring contaminants from the larger drainage basin, while air currents deposit pollutants from even farther afield. Because it takes up to 100 years for the waters to en- ter and leave the Great Lakes system, pollutants tend to remain within the system for a long period of time. In 52 Contaminant vva te r continue ci Lake Superior St. Marys Lake Huron St. Oair St. Clair Hiver Lake discharge to River discharge to River discharge to Lake St. Cfair St. Marys River Sources St. Clair River Sources St. Clair Sources Chloride 251,856 34,924 320,000 400,481 4,200,000 490,927 Phosphorus 1,749 120 720 222 5300 3,544 Zinc 266 41 130 79 1,100 388 Lead - 12 7,500 21 160000 179 Cadmium - 0.0021 .. 0.321 - 4.6 Mercury 0.1901 0.0067 O.09 0.0421 6.6 0.3997 PCBs (total) 0.06176 0.0090 0.0 (nd) 0.0900 0.2750 0.0293 Hexachlorobenz eae 0.004752 0.0 (nd) 0.000016 0.01 0.0295 0.7865 0.00562 Mirex - 0.0 (nd) ';!%:■ Contaminant Lake St. Clair discharge to Detroit River Detroit Detroit River Lake Erie River discharge to discharge to Sources Lake Erie Niagara River Niagara River Sources Niagara R. Lake Ontario discharge to discharge to Lake Ontario St. Lawrence R. Chloride Phosphorus Zinc Lead Cadmium Mercury PCBs (total) HexachlorobcnzEue Mirex 3,828,000 4,650 667 69 10 5.9 0.81 0.19 1,449,956 3,958 1,440 247 25 8.86 1.051 0.00343 4,704,000 7,700 1,428 93 18 14 1.86 0.19 1356 279 613 43 585 0.37 8.1 0.1264 2.20 0X720 OJ5577 O0838 O.0(nd) 0.0 (nd) 2,074 609 593 11.8 10.54 0.2290 0.0171 17,016,955 7,432 0.1014 0.00548 OÔ05497 Motes; *-" indicates data not available. * data drawn from various sources, 1984-1987 dources: Environment Canada, USEPA, Michigan Department of Natural Resources, New York State Department TOTAL "WESTERN BASIN LOADS x10 Metric tons/year 30 25 20" illIlllBililliiviil MDŒ a - CO ^ 05 O) O oj m t m f" Mean-1 Standard Qewaton ■i 1 3CO -s "^ ^ J 1 ^J T5 _ — ' HI — » — ■ TD ° '75 76 77 78 73 30 31 '82 33 34 35 36 37 39 39 30 31 water continued Figure 9.5a: Average concentrations of PCBs, in young-of-the-year spottail shiners, 1975-1991 cont'd Niagara River tmicrcgrams/gram) T Tnra ^j-Maan-1 Standard Owiaiion 1000 h aco i i 600 j 4CO '"apo :~ PtceCkeek (micrograms/gremj N NotOxacwd ■R- Maan • 1 Standard Dmfaaton ^J- M«an -1 Standard Pcwiatirai 350 '306" "250' SCO'' "Ï50" Ï00 50 ' 0' I J»_ ~ NT '75 76 77 78 '79 '80 -81 '82 '83 '84 B5 '86 '87 B8 '89 '90 "91 Since then, loadings of persistent toxics have de- clined significantly, mainly because of efforts by govern- ment and industry to reduce or eliminate the manufac- ture and use of mercury, PCBs, organochlorine pesti- cides and some other toxic substances, and to reduce or eliminate discharges of toxic byproducts such as dioxins andfurans. The reduction in loadings has been matched by a corresponding decline in concentrations of toxic sub- stances in fish tissues during the 1970s and 1980s. Be- cause of their tendency to accumulate many of these substances, fish are a particularly useful indicator of the presence of toxic contaminants. Not only are the higher concentrations in fish tissue easier to detect than the lower levels in the surrounding water, but the presence of a contaminant in fish also indicates that the substance is biologically available and making its way through the food web. Ontario has monitored the concentrations of more than 25 toxic substances in young-of-the-year minnows (spottail shiners) since 1975. Specimens have been col- lected and tested from more than 150 sites on the Great Lakes and their connecting rivers. As the graphs in Fig- ure 9.5 show, levels of PCBs have for the most part dropped substantially since 1975, although the rate of decrease has levelled off in recent years. Levels of mer- cury and of DDT, chlordane and other organochlorine pesticides have shown a similar decline. In spite of a general improvement in levels of per- sistent toxic contaminants in the lakes, excessive levels of some contaminants are still found in a number of areas. In the most recent sampling of spottail shiners (1990- 91), for example, PCB levels exceeded the IJC's aquatic life guideline of 100 parts per billion (which is intended to protect fish-eating wildlife) in 14 of the 38 locations surveyed. The highest concentrations in Ontario waters were found in fish from Etobicoke Creek on the west side of Toronto (Figure 9.6). Mirex (an organochlorine pesticide) was also above the guideline at five locations (two in the lower Niagara River, two in Lake Ontario and one in the SL Lawrence River). Mercury levels above the consumption guidelines continue to be found in sport fish in parts of Georgian Bay, Lake Erie and the SL Lawrence River. Instances of exceeding the guidelines for dioxins and furans in sport fish have also been reported from Peninsula Harbour 82 water continued Figure 9.5b: Average concentrations of DDT in young-of-the-year Spottail Shiners, 1975-1991 Hum&erRjver N luouctit fmjcrograms/grem) T 1*»» 500 500 400 3ÔÔ" tod o 3 J 7S 76 '77 '78 79 "80 31 32 '83 34 35 "SB '87 '88 83 30 '91 Niagara River M MxOMCUd Mean -1 standard Dminon Cmicrogrems/gremJ T Tract 35D 300 B; 25D ^ 200 If'"" g; . 1S0 I JB| 100 j 3 3 "i ' Mean-1 Standard D&xbud so ....... —, _j 75 '7S '77 78 '79 '80 31 32 33 34 '85 86 37 '88 39 '90 Kam River N NotCecacud (micrograms/gram) T Trace 200 gp- Maer. .1 Sanaa-d Deviation ; ~m3" Maan-1 Standard Osyiecjon Pike Creek N ** [mjcrogram/gram] T Tree» ~Îo5 ■T- Mean *1 Standard OeuBUoo "f-Meao _J- Mean -1 Standard Deviation 150 100 ~~§s~ 75 76 77 7B 73 BO -81 32 33 34 35 '88 '87 '88 39 '90 31 80 "ecf" "40" "20" o 3 J*= ^ £ ssj ■! '75 78 77 '78 '79 30 31 '82 '83 34 35 3S '37 '88 '83 30 31 Leamington N NocOetacud tmierograms/gram) T Traoe 200 ™*|-MaMi :wj- Meat -1 Standard DevasDon Standard Deviation 150 100 50 "~"6~ Zi .V.S ~3 m. 75 78 '77 78 73 '80 31 82 '83 '84 35 36 37 38 39 '90 31 S3 water continued Figure 9.5c: Average concentrations of Chiordane in young-of-the-year Spottail Shiners, 1975- 199 1 Cmîcro g ram/g ram) Humbea River N NotDateoad T Tm ■fr Meoo »1 Standard Dm»' _j- Mbkv-1 Standard OevaKion 850 2Cb" "•ISO 100 50 •3-, 75 76 '7? 78 73 '80 31 32 33 34 '85 -SB '87 T_N IN '89 '90 31 Cm'crog rams/gram) Niagara River N NotDataeud T Trees :-X Mean«1 Standard Dswsucn Mean-1 Standard OaMaton SO 7D SO SO 40 "30 SO •JO N T N N N N 75 78 77 '78 '79 '80 '81 32 '83 '84 -85 36 37 "88 "89 -90 '91 Kam River [micrograms/gram) 6 N NotDaceoad T Trace KT Usas -1 Standard Oeaaoon ~j- Mean 4 - Mean-1 Standard Oevajoon N N N N N 75 76 77 78 79 '80 31 BS '83 '84 '85 '88 '87 38 Ï9 'SO "91 PjkeCseek (micrograms/gramj N Not T Trace ■7- Mean «1 Standard Omnation ™f Mean -r- Moor -1 Standard Onieeon SO III i M I'j 1 <•* T T '** N N N 75 7B 77 78 79 -80 "81 '82 -83 '84 35 '86 «7 '88 '89 "90 'SI Leamington N NotOataoed [microflrarns/grorn} T Trace ML' 35 3D "25 20 "Ï5 10 5 N I u "Zi N N "D N 7S 76 77 78 79 30 31 32 33 S4 35 36 37 38 39 30 31 1 SA and Jackfish Bay in Lake Superior, from the southern part of Lake Huron and from Lake Ontario, especially the western end, where organic contaminant loadings are higher than anywhere else in the Canadian Great Lakes. Area:; of coocaro Concentrations of pollutants are usually heaviest in inshore areas, where they enter the lakes, but decrease rapidly offshore as the pollutants are diluted or settle to the bottom. Consequently, water quality in the open wa- ters of the lakes is generally good. The serious problems tend to be found inshore, in the harbours and bays ex- posed to high levels of human activity and along the connecting waterways that join the lakes to each other. In 1985, the International Joint Commission identi- fied 43 areas of concern where pollution was serious enough to impair the water for human use or to cause serious ecosystem damage. Of the 43 areas, 12 are on the Ontario side of the lakes and five are located along wa- terways shared with the United States. These are not the only areas in the Great Lakes where environmental problems exist, but they are the ones in which the most serious and extensive problems have been identified so far. Typical problems, as shown in Table 9.2, include water that is unsatisfactory for recreational, agricultural, industrial, or domestic use, and sediments that are so contaminated that dredging and the disposal of dredged materials must be restricted- In addition, there is a wide variety of effects on wildlife and natural communities. Some of these effects have shown up in dramatic fashion as tumours in fish or as deformities in fish-eating birds and mammals. Others have appeared more subtly as shifts in the proportions or populations of various bot- water continued Figure 9.6: Total Concentrations of PCBs in Young-of-the- year Spottail Shiners, 1990-1991 (pft/gl < N NoeOettcott T trta 500 400' 300 200 M UC Aquatic Life Guideline B ■ I N | N N T t||e||§NNt| § * Ifï 5 E 3 fps/g) "sob™ ""560"' ~40b~~ 300 200 N NocOetBcottf UC Aquatic 100 Lïe Guideline O ttlt Itt iIiaI. !|i!fi!!1iilïjiil ^Mi oie =|g£ |o ■ " ° -- J -§ <3 | m £ là 5 m tom-dwelling (benthic) organisms. Loss of habitat due to shoreline development is also a common concern. Most of these problems are related to continuing long-term sources of conventional and toxic pollutants. In a few areas, however, the problems are mainly the re- sult of historical causes, as in the case of Collingwood where debris from former logging and shipbuilding activities had contaminated the harbour bottom. r 65 water continued Area of Concern Effects on Contaminated Eutrophïcation Rsh fish, wildlife sédiments excess algae consumption Habitat Loss Drinking H2O quality Dosed beaches Lake Superior Peninsula Harbour Jackfish Bay NipTgonBay Th under Bay Lake Huron Co Hingwood Harbour Severn Sound Spanish River Harboar lake Et ie Wheadey Harbour Lake Ontario Ham H t on Harbour Metro Toronto Port Hope Bay of Quinte Connecting channels St Mary's River St Qaîr River DetroitRIver Niagara River St. Lawrence River Undoing the damage Since 1970 there has been a good deal of progress in reducing human stresses on the lakes. In addition to the reductions in phosphorus loadings and phase-outs or restrictions on the use of persistent toxic contaminants such as PCBs, organochlorine pesticides and mercury, substantial reductions have been made in discharges of many common pollutants. The pulp and paper industry, for example, reduced discharges of biochemical oxygen demanding materials from Ontario mills by more than 60 per cent between 1971 and 1990 (Figure 9.7). Simi- larly, since 1975, Ontario steel mills have reduced dis- charges of ammonia by 65 per cent per tonne of produc- tion and cyanide by 90 per cent, although they have not made the same progress in reducing discharges of oil and grease (Figure 9.8). In the past, efforts at reducing pollutant loadings to the lakes have focused mainly on municipal and indus- trial point sources, and they continue to do so now. That is because they are usually easier sources to identify and control. Even with the gains that have been made so far, there is still room for improvement in controlling mu- nicipal and industrial discharges. Not all municipal sewage systems provide adequate treatment for chemi- cals like phosphorus and many of them cannot prevent the discharge of raw sewage during storms. And while 86 water continued many companies in the industrial sector have made enormous progress in pollution reduction, others have been less effective or consistent in their efforts. A major effort to further reduce pollution from these sources is now being made through the province's Municipal Industrial Strategy for Abatement (MISA). Initiated in 1985, MISA has been developing "Clean Wa- ter' effluent quality regulations and guidelines and a monitoring program for municipal sewage treatment plants and major industries that discharge wastes direct- ly into Ontario waterways. About 170 industries and nearly 400 municipal sewage treatment plants are in- volved in the MISA program and most of them dis- charge directly into the Great Lakes or waters flowing into them. Although final Clean Water regulations are still un- der development for some industries, the program al- ready appears to have had some effect on reducing pol- lution discharges. In 1985, two-thirds of the industrial dischargers tailed to comply with their pollution limits at least once during the year. By 1991, nearly half of the companies had no compliance failures. Overall, compa- nies meet their monthly discharge limits for individual pollutants about 90 per cent of the time. Total dis- charges of pollutants from these companies have fallen from more than 1,600 tonnes per day in 1985 to about 1,400 tonnes per day in 1991. Municipal sewage treatment plants also are improv- ing their operating procedures and the quality of their effluent The performance of these plants is critical be- cause they handle sanitary sewage from approximately 4,000,000 households in the province as well as liquid wastes from more than 12,000 industrial establishments. Figure 9.7: Toixt bjologicai oxtgen dsman» or- t>ms and papes MILLS OPERATING Bi ONTARIO, 1971- 1390 millions of tonnes/year 350 _, 300 250 200 "Ï5Q" lôo" "* * % % B » 71 '73 -82 '83 "B4 «5 '86 "87 -88 -89 ~90 FlGtSŒ 9A ANNUM. DISCHARGES HT ONTARIO STEEl KlltS Of AMMONIA, CVANIDEvANDOIL AND GREASE PER TONNE OF PRODtfTnON, 1975-1990 kilosrams/tonne/year 2.0 Ammonia Cyanide 03 and grease 75 76 "77 78 73 "80 "81 ~S2 '83 '84 -85 '86 '87 -88 -89 'SO FîGi3^£9.9t Percentage of sewage treatment plants exceeding EFFXOENT GUIDELINES, 19*6-1990 67 water continued In 1986, 42 per cent of the plants involved in the pro- gram exceeded their effluent guidelines. By 1990, the proportion had dropped to 24 per cent The greatest im- provement has come in meeting guidelines for total phosphorus (TP). Instances of exceeding the guidelines in this category dropped from 35 per cent in 1986 to 14 per cent in 1990 (Figure 9.9 ). Another line of attack in cleaning up the lakes is di- rected at the areas of concern. Remedial Action Plan teams (RAPs) have been set up in each of these to devel- op and implement plans for restoring water quality and habitat. The plans are being developed by federal and provincial agencies in close consultation with the local municipalities, industries, residents and others who have an interest in the area. In the case of sites on waterways shared with the U.S., the process also involves co-ordi- nation and liaison with governments on the American side. The effort required to clean up a particular area of concern depends on the complexity of the problems af- fecting it and the objectives the community wants to achieve. Complete remediation of an area could involve not only reducing polluting discharges from major point sources such as local industries and sewage treat- ment facilities but also reducing pollution from non- point sources such as farms and urban areas in the surrounding watershed. In addition, contaminated sedi- ments might have to be removed to prevent the resus- pension or recycling of pollutants, and measures taken to restore fish and wildlife habitat. Before any of this can be done though, a detailed assessment of environmental conditions and possible solutions has to be carried out Hamilton Harbour is an example of what can be accomplished. For most of the present century it has been one of the most heavily stressed and degraded water bodies on the Canadian side of the Great Lakes. With the second largest cargo tonnage of any Canadian port on the lakes, the largest concentration of heavy in- dustry in the country, and a population of more than 600,000 people, the harbour receives very large dis- charges of industrial and municipal wastes, large vol- umes of urban runoff and spillage from the loading and unloading of ships. Development along the shoreline has also been destructive, eliminating about 75 per cent of the bay's original wetlands and destroying the nursery for what, at the turn of the century, had been the largest fishery on Lake Ontario. Remediation efforts have been underway since 1970 and have been part of the RAP process since 1986. These have focused largely on point sources. Hamilton's two large steel companies, for example, have installed treat- ment facilities for removing contaminants such as chromium, ammonia, cyanide, oil, phenols, and solids, while the Regional Municipality of Hamilton- Went- worth has installed holding tanks to prevent the dis- charge of raw sewage during storms from its sewer sys- tem. As a result of these and other efforts, provincial wa- ter quality objectives are now being met in most areas of the harbour. Populations of gulls, herons and cor- morants, seriously threatened by reproduction problems in the 1970s, have rebounded dramatically. In 1993, for the first time since the 1940s, swimming was permitted (at two locations) in the harbour. Yet, in spite of these improvements, there is still a distance to go before the harbour is fully restored to health. Eutrophication remains a problem and nuisance growths of algae are still abundant Contamination of sediments, mostly from past industrial discharges, is a major problem. The fish population is stable but still carries large accumulations of toxic substances and is dominated by species, such as carp, that can tolerate low Bioaccumulation and Biomagnifîcation DDE, a byproduct of the pesticide DDT. is present in Greet Lakes water in such small amounts that it can be detected only by the most sophisticated analytical equipment. Yet it has been strongly linked to eggshell thinning, embryo death, dub feet, crossed bills and a variety of other birth defects m fish-eating birds such as double-crested cormorants and herring guïs. How can almost infinitesimaSy smaJi environmental concentrations of a substance Use this have such devastating effects? Two interacting phenomena, bioaccumufetion and biomagntficauon. provide much of the answer Stoaccumutatkm refers to the tendency of substances 6ke ODE, PCBs, dioxins and furans, and other chlorinated organic chemicals to accumulate in living tissue. These substances tend to be much more soluble in fat than water and are not easily broken down by metabolic processes. As a result, much of an organism's intake of these substances is neither destroyed nor eliminated but is stored in its body fat instead. Heavy metals like mercury do ncit bbaccumulate in their metallic form, but must first be converted to an organometaBic compound. In the case of mercury, this is done by micro-organisms in the water and bottom sediments that convert it to methytmercury. a form that is readily absorbed by fish and Dther organisms and stored in musde tissue. Bioaccumulabve substances are initially taken up from the water by plankton and bottom-dwelling organisms. They provide food for bhy animals whtch. in turn, are eaten by small fish, which are preyed upon by larger fish, and so on up the food chain. Each predator consumes all the substances that aH its prey have bio- accumulated in their lifetimes. Thus, at each link in the food chain, concentrations of these substances may increase hundreds of trnes, depending on how much Bach organism retains of its intake. This process is known as biomagnificatian and because Df it, concentrations of persistent toac contaminants m an animal at the top of the food chain, such as a herring guH^maybe 10 mSbon times greater than the levels that can be detected in the water. water continued oxygen and turbid water conditions. Zebra mussels are also well established in the harbour. Dealing with these problems will require further reductions of pollution loadings, especially from municipal sewage systems, re- moval and/or stabilization of contaminated sediments and restoration offish and waterfowl habitat Improving Hamilton Harbour to its present condi- tion has already cost close to half a billion dollars. About 80 per cent of this has been spent by industry, and most of the rest by local municipalities. It is estimated that re- maining improvements will cost a similar amount, most of which will be required for further improvements to the sewage systems that discharge into the harbour. Important progress has also been made in a num- ber of other RAP areas, such as Collingwood and Severn Sound. By the end of 1993, Hamilton, Collingwood, Severn Sound and the Bay of Quinte had submitted de- tailed remediation plans to the provincial and federal governments and the remaining sites are expected to fol- low suit before the end of 1996. In many areas, however, it will take several years before all of the recommended actions can be completed and the aquatic environment restored to a reasonably healthy state. In looking at the condition of the Great Lakes sys- tem as a whole, it is important to recognize how much progress has been made. The lakes are in substantially better condition than they were 25 years ago and further improvements can be expected. But it is also important to recognize that the gains that have been made so far are only partial solutions to some very large and com- plex problems. The challenges that remain - particularly the problem of persistent toxic contaminants - are very daunting. Restoring and protecting water quality in the Great Lakes will remain an environmental priority well into the next century. Chapter 10 Groundwater When Ontario's freshwater resources are considered, its abundant rivers and lakes come first to mind. But, in fact, much more of the province's water is to be found beneath the surface, as groundwater. About 2.8 million Ontarians - more than a quarter of the province's population - get their water from the ground. Many of them live in the country and draw their water from private wells, but more than half live in towns and cities, including larger centres such as Kitch- ener, Waterloo, Guelph and Woodstock, where water comes from municipal wells . Altogether, it is estimated that there are more than 500,000 wells in Ontario, and between 14,000 and 22,000 new ones are being added every year. Apart from being used for drinking and household purposes, this water is used for irrigation, livestock wa- tering, fish hatcheries, swimming pools and a variety of commercial and industrial purposes. In addition, groundwater is an important source for replenishing surface waters. On average, about 20 per cent of annual streamflow comes from groundwater. In some areas, this may be as high as 60 per cent and in summer and early fall, when surface flow diminishes, some streams may be fed entirely by groundwater. Groundwater occurrence Groundwater is found in geological formations that were created thousands, even millions of years ago. It is replenished mainly by precipitation and snowmelt that percolate down through the soil. It occurs in two layers. The upper layer, the unsaturated zone, contains liquid water as well as water vapour and air. The lower layer is the saturated zone, or the groundwater zone, and here 70 Snowmeie Fioure 10.2 Groundwater Flow Groundwater occurs in two layers. The upper layeo the unsaturated zone, contains liquid water, water vapour and ar. The tower layer is the saturated zone, where all empty spaces in the soil and bedrock are filled with water. The top of the satur- ated zone is the water table. Groundwater is replenished by précipitation and snow- met that percolate down through the sol. ; all empty spaces in the soil and bedrock are filled with water. The top of the groundwater zone is the water table and may lie anywhere from a metre to more than 50 metres below the ground, depending on the geology of the area, the season and local precipitation condi- tions. Groundwater eventually returns to a stream, lake, or ocean, but it flows slowly and it may take hundreds to thousands of years before some of this water returns to the surface and enters the next phase of the water cycle (Figure 10.1) Geological formations that can store and transmit a large amount of water are known as aquifers. These may be small formations limited to an area of a few hectares or they may be quite extensive, covering several hun- dreds or thousands of square kilometres. Coarse gravel and sand make a particularly good aquifer that can yield a plentiful supply of pure water. Silts give up their water more slowly and clay acts as a barrier to the movement of water. 71 water continued The natural quality of groundwater is very much influenced by geology. Frequently, minerals in the aquifer or in surrounding formations may affect the colour, flavour, smell, or hardness of the water, though without necessarily affecting its suitability for drinking. In some cases, though, the water may be of naturally poor quality and unfit for human consumption. Exces- sive levels of metals such as arsenic, cadmium, nickel, lead, copper, zinc, and uranium sometimes occur in groundwater in parts of northern Ontario. In parts of southwestern Ontario, groundwater can be contaminat- ed by hydrocarbons from oil and gas deposits, while in the south and southeast salt and saltwater deposits occur naturally. Oon&smtttStton by human activities Compared to surface water, groundwater is less sus- ceptible to contamination. Nevertheless, it can become contaminated by human sources. Once this has hap- pened, the aquifer may remain contaminated for cen- turies. With present technology, cleanup is difficult and sometimes impossible Frequently the best that can be done once groundwater has been polluted is to prevent the contamination from spreading. In farming areas, there is potential for groundwater contamination from fertilizers, pesticides, manure, pe- troleum products and milkhouse wastes, which can re- sult in high levels of nitrate, bacteria and toxic chemicals in the water supply. Septic sewage systems are another potential source of nitrate and bacterial contamination. There are ap- proximately one million private septic systems in On- tario and many of these are now 20 to 30 years old and reaching an age when they will be more likely to mal- function. Groundwater in some communities has been dam- aged by leakage from underground fuel storage tanks at gas stations and other sites. In most of these cases, the contaminated aquifers have been small and fewer than a dozen homes have been affected, but cleanup costs have still ranged from tens of thousands to hundreds of thou- sands of dollars. In the mining country of the north, hundreds of deep boreholes are drilled every year in search of miner- als. These are left open when they are finished and pro- vide a route by which contaminants can penetrate deep underground. In the southwest, old, improperly aban- doned oil wells provide pathways by which briny, petro- leum-contaminated water can enter freshwater aquifers. Road salt is a problem in many parts of the province. Approximately 1.4 million tonnes of it are spread on Ontario's roads and highways every year Some' of this eventually seeps into the groundwater and raises its chloride content to unacceptable levels. The Ministry of Environment and Energy investigates about 200 cases of road salt contamination a year. Both municipal and industrial landfills are a possi- ble source of groundwater pollution, but those currently in use are subject to strict controls and the risk from them is slight Spills and leaks from industrial storage tanks and production facilities, however, are still occa- sionally the cause of major incidents of groundwater contamination. One such case came to light in 1989, when it was discovered that the groundwater supply for the town of Elmira had been contaminated with N-nitroso dimethy- lamine (NDMA) that had leaked from a local chemical plant L water continued Other incidents of contamination by toxic chemi- cals have occurred at Smithville, where the groundwater has been contaminated with PCBs, and, more recently, in Manotick, where 74 wells serving 200 to 300 homes and businesses were found to contain perchloroethylene, a dry cleaning solvent that had leaked from a storage tank at a dry cleaner's shop. Dealing with such incidents is expensive. The pollu- tion source must be identified and the contaminants tracked, contained and, if possible, cleaned up. In addi- tion, bottled water and filtration units must be supplied until the original water supply can be cleaned up or an alternative supply established. An interim water supply for Manotick is expected to cost in the vicinity of $5 million. To date, $15 million has been spent in Smithville and costs in Elmira could go as high as $50 million. Groundwater qai-lity Groundwater is not monitored systematically throughout the province. Consequently, much of the in- formation that we have about groundwater quality comes from complaints that MOEE has been asked to investigate. The ministry deals with about 2,000 of these cases every year. The problems vary from region to re- gion, but the most important involve contamination by agricultural chemicals and wastes, road salt, toxic chem- icals, and industrial wastes (Figure 10.2). The number of complaints is relatively small - about one for every 250 wells in the province - but, un- fortunately, complaints only serve as an indicator of problems that have already been recognized or suspect- ed. Obviously, there are other cases in which water qual- ity has been impaired but has gone undetected. Some valuable information about the effect of agri- cultural practices on groundwater quality comes from a recent survey of well water from 1300 Ontario farms. Carried out between October 1991 and March 1992, the survey sampled each of the wells for common agricul- tural contaminants: nitrate nitrogen, total and faecal co- nform bacteria, and pesticide and herbicide residues. Tests for petroleum contaminants were also carried out at 160 of the sites. The results showed that 37 per cent of the wells contained one or more of these contaminants at concen- trations above the provincial drinking water objectives. Thirty-one per cent exceeded the maximum acceptable level for coliform bacteria and 20 per cent had faecal co- nform bacteria. More than 13 per cent exceeded the maximum acceptable concentration for nitrate. Eight per cent of the wells had detectable levels of pesticides and one well exceeded the interim maximum acceptable concentration. No petroleum -based contaminants were detected in any of the 160 wells tested. A follow-up study in the summer of 1992 produced a similar pattern of results but showed a slightly higher percentage of contaminated wells in most categories. The surveys indicate that unsuitable well location, improper well construction, or poor well maintenance were the causes of well contamination, in the majority of cases. The surveys, however, do not provide evidence of widespread aquifer contamination in rural Ontario. 73 water continued Figure 10.2: Groundwater complaint investigations by region Central Regîon Southeastern Rec4qn Weil Construction 5.1% Septic Systems 7.9% Trace Organes Well . Construction 15.8% Petroleum Hydrocarbons 22.6% Water Quantity 20.6% Northeastern Region SotmîWEsreRN Region Ptetroteum Hydrocarbons 22.6% V, WeH Construction 6.4% Septic - Systems 6% Trace Organes 5% Well. Construction 2% -Petroleum Hydrocarbons 10% Agricultural 9% Water Quantity 34% Northwestern Region W£ST Central Region Agricultural 5% Industrial Waste 5% Septic Systems 5% Petroleum Hydrocarbons 65% Water Quantity 1 5% Petroleum Hydrocarbons 20% Well Construction 5% Agricultural 15% Water Quantity 15% 74 water continued Groundwater: is. there enough to co around? Although Ontario has plenty of groundwater, from the point of view of the user, not all of it is in the right place or of the right quality. Consequently, some aquifers must meet very heavy demands for usage. In some cases, water is drawn off faster than it can be re- plenished, the water table drops and some wells may go dry. This situation is known as aquifer mining. Water quantity problems are fewest in northeastern Ontario but make up 15 to 20 per cent of the complaints investi- gated in most other parts of the province. In southwest- em Ontario, water quantity problems account for 34 per cent - the largest single category - of the complaints in- vestigated (Figure 10.2). Apart from natural causes such as decreased precip- itation, water quantity problems may arise because of increased demand, improved surface drainage and paving and house construction. Heavy pumping may temporarily dewater the area around the well Less com- monly, the supply may be diminished because of mining of the aquifer by large users or disruption of the groundwater flow by quarrying operations. To prevent supply interference due to high-volume pumping and aquifer mining, the province requires any- one taking more than 30,000 litres of water a day to ob- tain a Permit to Take Water (PTTW), except where the water is for private domestic and livestock use. The PTTW program promotes the efficient development and fair sharing of water in Ontario. Before a permit is issued, the applicant has to submit to MOEE all the nec- essary information and supporting documents. Vari- ables of water availability and water use are considered by the ministry as factors which would place limits on the terms and conditions of the permit Failure to comply with the terms and conditions can result in the cancellation of the permit Protecting groundwater As Ontario's population expands, so will the de- mand for its groundwater and so too will the risks of contaminating it Improved ability to manage this in- creasingly vulnerable resource will be needed to protect it Municipalities have a role in protecting groundwa- ter through their planning procedures. Individual well owners also have a particular role in the management of this fragile resource, through the proper application of construction, maintenance and abandonment proce- dures. One of the most pressing needs at the moment is for more information about the state of the resource. To provide this, the ministry is now taking preliminary steps towards establishing a provincial Groundwater Quality Monitoring Network. Further information about water quality will become available as a result of improvements to the ministry's Water Well Information System. This computerized database, which has been in operation since 1972, describes the location and physical characteristics of approximately 400,000 water wells in the province. With better monitoring and data collection, the ability to observe changes in water quality over time and to detect contamination problems at earlier stages should gradually improve. Better information also will increase the ability to identify those aquifers that are most vulnerable to pollution, so that they can be pro- tected against inappropriate land uses. 75 water continued In addition to preventing contamination, further research, particularly into methods of decontamination, will add to the capability to deal with contamination when it does happen. Ultimately, protection of groundwater depends on the actions and support of an informed public. Chapter 1 1 Water and the individual Whether people drink it, swim in it, or eat the fish that live in it, water has the potential to transmit disease and harmful chemicals. In the more populated parts of the province, lakes and rivers are exposed to pollution from many sources - industries, farms, roads and highways, sewage systems and the air. Even in remote areas, surface waters may contain bacteria or parasites from wildlife. Figure I 1.1: Results of Drinking Water Survey, i 985 -92 Tests that metODWDs 166136 Tests that exceeded ODWOs Tests that exceeded ODWOs Tr*ialo- methanes 3 Groundwater is less susceptible to pollution but, as has been already seen, it is by no means invulnerable. Drinking water There are almost 500 municipal water supplies in the province. Of these, about 200 use surface water and the rest use groundwater as a supply source. Surface wa- ter generally has to be treated before it can be considered safe for drinking. In municipal water supplies, this is commonly done through the use of chlorine to disinfect the water and aluminum sulphate to clarify it The water may also be treated to improve its taste or appearance and to control other characteristics such as corrosiveness and hardness that might limit its use or interfere with the distribution system. Municipal tap water is tested regularly for bacteria to ensure that it is microbiologically safe to drink. In ad- dition, the quality of municipal water supplies has been closely monitored by the Drinking Water Surveillance Program (DWSP) since 1985. The DWSP monitors as many as 180 substances and has produced more than two million analysis results since its inception. As of 1992, 109 municipal water systems serving about 80 per cent of the population are involved in the program, which will eventually include all municipal water sup- plies in the province. Water quality is judged by comparing the program's monitoring results with the limits set out in the Ontario Drinking Water Objectives (ODWOs). The ODWOs specify acceptable levels for more than 100 substances or characteristics, including bacteria, chemicals, metals, and radioactive materials. Test results are passed on to local authorities, who can take remedial action if any of the levels exceed a health-related limit- 7B So fer, testing has shown the treated water supplies of the participating municipalities to be very safe, both bacteriologically and chemically. Between 1985 and 1992, for example, more than 165,000 analyses of health-related criteria were carried out, but only 66 in- stances of exceeding the drinking water objectives were reported (Figure 11.1). During the same period, close to 350,000 tests were carried out for an additional set of more than 90 potentially harmful chemicals, including pesticides, polyaromatic hydrocarbons, volatile organic compounds and chlorinated organic compounds. The test results showed the presence of 36 of these chemicals in about three per cent of the samples, but all at very low concentrations (Figure 11.2). Rot:rea&:io>oiiî use of waiter Swimming in bacterially contaminated waters in- creases the risk of contracting ear and eye infections and gastro-intestinal diseases. According to provincial guide- lines, water is unsafe for swimming if the average faecal coliform density is greater than 100 organisms per 100 millilitres (mL) or if the total coliform density exceeds 1,000 per 100 mL In the more populated areas of southern Ontario, these levels are often exceeded in many localities and commonly result in the closing of beaches by health au- thorities (Figure 1 13). In many cases the problem is a consequence of sewage systems being overloaded during heavy rainstorms and conditions generally improve within a few days. water continued Figure 11,2: Resuets of anaixses of drinking water for synthetic organic contaminants and pesticides, 1985- 1992 Trace Results 9898 ' A trace result is e value so low that i carrot be confident^ measured A passive result shows that a substance is present above trace levels and can be confidendy measured. Figure U3: Beach closures, 1986-90 fj Never closed M Closed at least once *& m .*$> 77 vaste management Since the 1970s, new regulations and improved waste management practices have been devised to control the growing output of waste and its impact on the environ- ment These practices are based on a hierarchy of dis- posal options, with the highest priority going to the reduction, reuse and recycling of waste that minimize déposai requirements. Asa relatively prosperous, mass production, mass consumption society, Ontario is a large producer of waste. During the last 30 to 40 years, its potential for -waste generation has been augmented by the prolifera- tion of a wide array of disposable convenience products, from coffee cups and diapers to printer ribbons. Packag- ing, whfch has become increasingly attractive both as a marketing tool and a labour-saving device, has also added to the waste stream. In addition, consumer de- mand for a steady flow of new products hastens the obsolescence, and the disposal, of the old. Wastes in Ontario are divided into two major streams: solid non-hazardous waste and hazardous and liquid industrial waste. Solid non-hazardous wastes do not require special treatment or handling. Hazardous and liquid industrial wastes, on the other hand, must have special handling to be disposed of safely. The chap- ters in this section examine each of these major streams. Chapter 12 Solid non-hazardous waste Solid, non-hazardous waste is what we usually think of as garbage. It includes not only kitchen waste and other household refuse but also wastes from industries such as manufacturing and construction, businesses such as stores and restaurants and institutions such as schools and hospitals. In 1987, all these sources in Ontario dis- posed of an estimated 8.9 million tonnes of garbage, or about one tonne a year for each person in the province. SO,V5£ BÏGHUCKÏS f ROVS THIS SECHON: In l987,Ontario generated one tonne of waste per bead of population. By 1992 this had been reduced by 25 per cent, to three-quarters of a tonne per head. Mue Box recycling now serves more than 3.2 million hous- es and apartments in the province and is regularly used by 90 per cent of the Ontario residents it serves. In J992, blue boxes diverted 431 ,000 tonnes of waste from landfills. By the end of 1992, more than 800,000 home composters had been distributed in Ontario. More than 100 communi- ties now offer central composting of leaf and yard waste- Ontario needs to increase its capacity to handle hazardous wastes. Because of limited disposal capacity, the quantity of PCB wastes in storage has increased dramatically. At the end of 1992, there were 1,751 PCB storage sites in Ontario. Ontario is afao sending more of its hazardous and liquid industrial wastes for out-of-ptovince disposai. Between 1987 and 1992, the proportion of hazardous and Squid in- dustrial waste being exported grew from about Sve per cent to 17 percent Overall, the amount of hazardous and liquid industrial waste being recycled has remained steady, bnt new pro- gran» have dramatically increased the amotmt of house- hold hazardous wastes being diverted from landfills. Between 1986-87 and 1992-93, the diversion rateofhouse- hold hazardous wastes increased from less than 50 tonnes per year to more than 1,600 tonnes. 7S waste management continued Disposing of that amount of material without harming the environment or endangering human health adds up to an enormous challenge and meeting it is demanding new and innovative approaches to waste management LsndNfËng Traditionally, most waste materials have been dis- posed of in landfills; most still are today. This method has the short-term advantages of cheapness and conve- nience. However, as old landfills reach capacity, new landfill space is becoming harder and more expensive to obtain. Many communities are reluctant to have landfills within their boundaries and the costs of geological, en- gineering and other studies are increasing as the assess- ment of environmental impacts becomes more detailed. Landfills also use up increasingly scarce land that could be used for other purposes, such as farming, building, recreation, or as a wildlife habitat As well, there are the nuisances of odours, dust, unsightliness and scavenging birds and animals. Landfills produce a certain amount of leachate, or polluted water, that forms as rainwater trickles down through the decomposing garbage and absorbs contami- nants from it If the soil surrounding the landfill is per- meable, the leachate may drain into nearby ground and surface waters, making them unfit for drinking or per- haps contaminating the food chains they support Landfills also produce methane gas as buried organic matter decomposes in the absence of oxygen. Other gases may be produced as well, including carbon dioxide and small amounts of toxic volatile organic compounds (VOCs) such as benzene and toluene. Apart from the danger of a methane explosion, these gases also contribute to atmospheric pollution and global warm- ing. Landfill sites account for about 35 per cent of all methane emissions in Ontario. To control these problems, the provincial govern- ment began regulating landfill sites in 1971. These regu- lations require close attention to local geological details in choosing a site so that the chance of groundwater pollution and other potential environmental effects will be minimized. The site must also incorporate features for the control of leachate and gases and steps must be taken when the site is finally closed to ensure that it re- mains harmless. incinération Incineration has been the most common alternative to Ian dtilling. It reduces waste to a fraction of its former volume and also produces heat that can be used to warm buildings or produce electricity. But incineration is also a source of common air pollutants, such as carbon monoxide and carbon dioxide, and acid gases, such as sulphur dioxide, hydrogen chloride and nitrogen oxides. In addition, it may release a variety of toxic substances into the atmosphere, such as heavy metals, dioxins and furans, benzene and other dangerous organic com- pounds. Modern incinerator technology can reduce these toxic emissions to very low levels, but it cannot eliminate them entirely. A further difficulty is that incineration still leaves a residue, in the form of ash, that must be landfUled. In- cinerator ash can amount to as much as 30 per cent by weight of the original waste and it is usually contami- nated with heavy metals and other toxic residues. These come either from toxic materials already in the waste stream or are produced by chemical reactions during combustioa In many cases, incinerator ash must be treated as toxic waste. Incineration is no longer widely used as a disposal option in the province. Apartment building incinerators were phased out in 1989 and the province banned the SO waste management continued construction of new municipal solid waste incinerators in September 1992. Incineration is still preferred for the disposal of some biomedical and hazardous wastes, however, because it is the safest and most effective way of dealing with them. As the use of incineration decreases, landfilling is the local disposal option for most communities. Dwornion - the three P.s To lessen the need for landfilling or incineration, modern waste management practices are placing more and more emphasis on diverting waste from disposal A quick look at what typically goes into the waste stream (see Who Throws Out What) shows just how much po- tential there is for reducing the amount of waste that must finally be disposed of. Much of what we discard consists of things that either did not have to be used at all (like some forms of packaging) or that can be used again - for their original purpose, another purpose, or as raw material for making something else. The principal methods of diverting waste from dis- posal - familiarly known as the three Rs - are reduction, reuse and recycling. As well as saving valuable disposal space, these methods also offer significant savings in the use of energy and natural resources. In some cases they can provide important financial benefits by treating waste as a resource. Reduction is the first choice because it promotes ef- ficiency in the use of resources, and eliminates the need for any additional handling of materials. It can be ac- complished through means such as eliminating unnec- essary packaging or redesigning products so that they use fewer raw materials and offer greater durability. Reuse extends the life of a product or materials be- yond a single use. ReûUable pop bottles are a familiar example, as are rebuilt toner cartridges for photocopiers and printers. Many people also reuse their shopping bags. While providing savings in raw materials and ener- gy for manufacturing, reuse can involve some additional costs if the product has to be cleaned or refurbished be- fore being used again. Recycling involves treating waste as a resource from which new products can be made. Many of the most common materials in the municipal waste stream, such as paper, plastic and glass, can be handled in this way. For all its merits, though, recycling is not as efficient as either reduction or reuse It involves additional collec- tion and handling costs, requires some consumption of energy (though usually not as much as manufacturing the same product from primary materials), and may it- self generate some wastes (as in the case of de-inking sludges from the recycling of printed paper). However, it is a practical way of keeping some items, such as news- papers, out of landfills. Recycling also depends on a demand for products made from recycled materials and on the ability of man- ufacturers to make them at competitive prices. Recogni- tion of the benefits of recycling has gradually created widespread public acceptance and strong demand for many different types of recycled papers, for example, but until the opening of two new de-inking plants in 1990, the supply of waste paper in Ontario often exceed- ed the capacity to process it As a result, paper intended for recycling occasionally ended up in landfills or was exported. Markets for waste paper, glass and plastic are now maturing and at the moment the demand for these ma- terials exceeds the supply. However, the market for waste glass is potentially fragile, as there is only one glass recy- cler in the province. waste management continued FIGURE 12.1: MATERIALS RECYCLED THROUGH THE BttJE BOX PROGRAM 1992 Other materials 6300 Glass 94330 Plastic ES90 aw corrugated csrdboerd 28120 Tonnes of waste diverted ! Figure 122: Number of households with access to the Blue Box system m Qntarjo, 1986- 1992 •SB™ 31 ^^Apannwt thousands of households 3S0O 3000 "°" 250O 2000 1500 1000 " 500 "6 *SS|Curt«Ma ■Depot 1986 1987 198B 1989 Source; Ontario Muto-Macenal Recycling Inc i , 1991 1992 Residential recycling is carried out primarily through the Blue Box program, although central recy- cling depots are also available in some communities. The system provides for the collection of such common waste items as newspaper, magazines, glass containers, metal cans, polyethylene terephthalate (PET) soft drink containers and rigid plastic (HDPE or high density polyethylene) bottles (Figure 12.1). Since its introduction in Kitchener in 1983, the Blue Box program has spread to more than 500 municipali- ties and now serves more than 3.2 million householders and apartment dwellers (Figure 12.2). The system is used regularly by 90 per cent of the people it serves. Only about three to five per cent of the waste collected is unmarketable and has to be sent for disposal. Composting is another variety of waste reduction, suitable for organic wastes such as vegetable scraps and garden waste. So far, more than 800,000 home corn- posters have been distributed by municipalities, with fi- nancial assistance from the Ministry of Environment and Energy's Municipal Reduction/Reuse Program. A recent study estimates the cost of managing wet waste by home composting at between $30 and $40 per tonne, which is considerably cheaper than today's landfill fees. Collection and central composting of leaves and yard waste were offered as well in more than 100 com- munities in 1992. Some are also looking into more ex- tensive programs, with curbside pickup and central composting of both kitchen and yard wastes. The city of Guelph plans to have such a program operational by the end of 1994 while the county of Northumberland has a similar program under consideration. In the industrial sector, recycling has been a com- mon practice in some industries for years. Printers, for example, have traditionally resold their waste paper to mills for pulping and wreckers' yards have turned dis- carded motor vehicles into scrap metal and parts since the earliest days of the automotive industry. Many other businesses, though, saw little value in such practices. This attitude changed in the 1980s, however, in re- sponse to growing public awareness of the problems of waste disposaL Many companies, and public institutions as well, came to see waste reduction and recycling as a mark of good corporate citizenship. Many of them also found they could save money by using resources more efficiently and reducing their waste disposal costs or by 82 using their waste as a resource. In addition, initiatives such as the establishment of the Ontario Waste Ex- change in 1978 have played a critical role by greatly expanding the market for industrial and commercial wastes. Another initiative that is expected to make an im- portant difference is the National Packaging Protocol (NAPP). Packaging such as bottles, cans, boxboard, plas- tic wrap and pallets makes up about a fifth of Ontario's waste stream. By the year 2000, NAPP aims to have re- duced these wastes to 50 per cent of their 1988 levels, interim targets of 20 per cent and 35 per cent have been set for 1992 and 1996. In the early 1990s, a number of municipalities also took further steps to encourage recycling by closing their landfills to some of the more common types of com- mercial and construction waste, such as wood, drywall, construction rubble, corrugated cardboard and office paper. Several municipalities also greatly increased tip- ping fees for companies and institutions using their landfills. These measures have not always had the desired ef- fect, however. Taking advantage of the removal of Amer- ican regulations forbidding the importation of waste, a number of companies are now exporting their waste to cheaper and less restrictive landfills in the United States. Approximately 1.3 million tonnes of waste were shipped to American landfills in 1992. Progr-îsss in mtaSBa management Through its Waste Reduction Action Plan, Ontario is attempting to cut the amount of garbage disposed of per person to 50 per cent of the 1987 level by the year 2000. So far, the per capita disposal rate has been cut by 25 per cent, from one tonne per person in 1987 to 0.75 tonnes in 1992. waste management continued Figure 123: Amount of soli» kon-hazakdous waste dispose 19s7and 1992 (thousands of td5wes} 1987(100%) Industrial, commercial institutional 3554 Residential 3627 1992(75%) industrial commercial and msttitrtionai wastes As Figure 12.3 shows, the biggest reduction has been in industrial, commercial and institutional wastes. In the mid-1980s, this category made up nearly 60 per cent of the total volume of solid, non-hazardous wastes. By 1992 it accounted for only 49 per cent of the total A significant part of these reductions has come from a de- crease in packaging. In addition, voluntary waste reduc- tion initiatives in the private sector have been very effective and are estimated to have diverted at least 600,000 tonnes of waste in 1992 alone. However, the economic slowdown of the early 1990s has undoubtedly also made a contribution to waste reduction. 83 waste management continued Figure 12.4; Btut Box Program: annual diversion (estimated} RssJdentiaS wastes With the expansion of Blue Box services, the amount of residential waste diverted from landfills has increased considerably. Since 1987, the amount collected through the program has risen from 29,000 tonnes to more than 43 1,000 tonnes, and the program now handles more than 10 per cent of all residential waste (Figure 12.4). Composting is also beginning to show appreciable results in the diversion of wet or compostable wastes. A 1989 study estimated that about 1.88 million tonnes of wet waste were produced in the province, with house- holds accounting for about two-thirds of the totaL In 1992, it was estimated that composting diverted at least 300,000 tonnes of wet waste, or about 16 per cent of the 1989 amount Tires Vehicle tires remain one of the most difficult wastes to deal with. They take up too much space and are too durable to be acceptable for landfilling and, although they are recyclable, recycling capacity has been slow to develop. As a result, tires have been stockpiled or export- ed to the United States for disposal Approximately 10 million tires are discarded every year in Ontario. In 1990, after the Hagersville tire fire, there were some four million tires in storage in the province. By 1993, this number had been cut in half, largely because of concerted efforts by government and industry to build an infrastructure for tire recycling. Tires can be retreaded for further use or converted to crumb rubber, which can be used to make a variety of products like matting, patio blocks, running tracks and car parts. Scrap tires also provide high-energy fuel for cement kins, where they are burned under controlled conditions to minimize air pollution. In 1992, about 40 per cent of scrapped tires were diverted from disposal to reuse, retreading, or recycling. That number is expected to rise to 60 per cent by 1994. LandMn Diversion can greatly reduce the amount of waste going to landfills, but it cannot eliminate all of it On- tario will therefore continue to need a substantial amount of landfill capacity, but in some areas much of what it now has is being rapidly used up and new land- fill space is becoming harder to find. Approximately 10 per cent of Ontario's 1365 active landfill sites will have reached the limits of their capacity within the next five years. This is a normal and manageable rate of attrition, but in central and southern Ontario the proportion is closer to 20 per cent The problem of disposal capacity is most acute in the Greater Toronto Area, where the two major landfills are nearing the end of their useful lives. The recent upsurge in waste exports to the United States, however, has taken some of the pressure off these sites. Apart from the problem of capacity, there is also some concern about groundwater contamination or gas waste management continued Generators of non-hazardous solid -waste fall into two categories - residential and IC6-I (industrial, commercial and institutional}. Until recently, IC&Iwastbe larger of the two sectors, producing almost 60 per cent of all -wastes disposed. As cfl992, IC&l accounted for orAy 49 per tent of the total A recent st tidy, based on data from 1989 provides abreakdown of the types of waste being thrown oat N T otabiy, paper {almost hatf of it news-print) and organic wastes are the two biggestitemsirrtrie residen- tial stream. Corrugated cardboard, wood» paper, organic materials and metal are the major 1C&I wastes. The construction and demolition in- dustry is the largest generator of IC&l rubbish, accounting fof 17 per cent of all waste in that sector. Another study estimates that packaging wastes, including paper products, glass, plastic, wood and metals, accounted for I .o million tonnes or 20 per cent of 01x300*5 municipal solid wastes in 1590. Ontario has the highest per capita consumption of packaging in Cana- da. However, because of higher recy- cling rates, the province ranks fifth m terms of per capita disposal of packagin g Residential 43% Total 100% Dtha-4% I /eut 3% Ptastcs3% Glass 3% iCSi 57% MetsJ6% Pt8St>cs2% Glass 3% leakage from landfills, especially from abandoned sites that were not subject to environmental controls when they were in use. There are currently 2334 closed land- fill sites in the province and MOEE has conducted a number of studies to determine whether any of them pose an environmental or health hazard. So far, no significant problems have been identified, although the investigation program is continuing. The most intensive studies have focused on sites lo- cated near houses, wells, or streams used for domestic water or recreation. Investigators carried out detailed hydrogeological studies at 21 of these sites, where there appeared to be some potential for the escape of gas or leachate. A gas evacuation system was installed at one site, eight were given a clean bill of health and the re- mainder were considered safe but recommended for further monitoring as a precautionary measure. Major active sites are subject to regular monitoring, and prob- lems are dealt with as they arise. 85 waste management continued FlGVSB 13.1: TlPES OF HAZARDOUS AND LK3UID INDUSTRIAL WASTE, 1992 Resins and plastics 4% Solvants and fuels 8% Moving away from throw-away By the end of the century, Ontario hopes to have a more environmentally acceptable system of waste man- agement in place, one that relies much less on landfilling and disposal and more on the elimination or diversion of waste through the three Rs. Good progress has been made towards this goal, but getting the rest of the way requires a further intensification of waste reduction efforts. How can this be done? Some small additional gains in waste diversion can be made by extending residential Blue Box and composting programs to more communi- ties. More may come from increasing the amount and variety of material collected through Blue Box pro- grams. In 1992, the average household diverted more than 131 kg of recyclables, but it is estimated that an improved program could raise that amount to more than 200 kg. More substantial gains can also come from the industrial, commercial and institutional sector through the extension of waste reduction activities to more companies and the improvement of programs already in place. With these objectives in mind, MOEE plans to re- quire all municipalities with more than 5,000 people to provide Blue Box recycling, yard waste composting and backyard composting programs. In addition, more than 7,000 large industrial, commercial and institutional sites will be required to initiate waste audits, waste reduction workplans and recycling programs. These efforts are ex- pected to divert another two million tonnes of garbage from landfills. Although these programs will place greater de- mands on Ontario citizens and companies, they will ul- timately pay back important dividends - reducing water and air pollution, improving resource and energy con- servation, and lessening the aesthetic impact of waste disposal on the landscape. Chapter 13 Hazardous and liquid industrial wastes More than two million tonnes of hazardous and liquid industrial wastes are generated in Ontario every year. They include an amazing variety of materials - every- thing from acids, contaminated sludges and PCBs to motor oil and discarded batteries - and all require spe- cial handling and disposal (Figure 13. 1). Wastes are considered hazardous if they are corro- sive, toxic, chemically reactive, ignitable or, like biomed- ical wastes, likely to spread disease. Non-hazardous liquid wastes do not present the kind of obvious threat to health and safety that hazardous substances do, but they may still have the potential to cause environmental problems such as turbidity or depletion of oxygen in watercourses or salinization of soils. waste management continued Many wastes present a special problem because they are both hazardous and liquid. Liquids are more difficult to contain and are, therefore, more prone to spills and seepage and more difficult to clean up. Major generators of hazardous and liquid industrial waste are required to register their sites and the types of waste they produce with the ministry. Figure 13.2 shows these waste generators by industry type. Although most of these wastes are produced by large industrial facilities, significant amounts also come from farms, mines, insti- tutions such as hospitals, universities and schools and small businesses such as service stations and dry clean- ers. Many common household items, such as solvents, cleaning compounds, paints and batteries, are also haz- ardous. Wastes can be managed on-site or off-site. The choice is largely determined by economies of scale, the type of waste and the availability of off-site treatment On-site management tends to be preferred by larger companies that generate substantial volumes of waste and can operate the necessary disposal procedures cost- effectively. Off-site disposal is more suitable for smaller companies or for small volumes of wastes that require expensive handling faculties. Approximately 40 per cent of the hazardous and industrial liquid waste produced in Ontario is disposed of on site. All disposal facilities, whether on-site or off-site, must be certified by the Ministry of Environment and Energy. However, only transfers of off-site wastes are tracked by the ministry. This is to ensure that these wastes are handled safely, since they must be transported to the disposal facilities on public roads and may require special precautions. Raj»! 13.2: GtoE&ATORSOFiUZARDOtJS AND UQUIO INDUSTRiAl WASTE, 1992 'ocverr.ment 6% a-ade 6% * agricukirai, foressy mwng, heafch and social services, and other service îndusGnes Carriers of these wastes must be certified by the ministry. Manifest forms describing the types and quan- tities of wastes being shipped must be completed by the generator, the carrier and the receiver of the wastes. A computerized system at the ministry verifies that gener- ator, carrier, and receiver are properly registered or certi- fied for the type of waste being handled and tracks the shipment from source to destination. This system en- sures that every load of waste that is generated is proper- ly managed and received at approved facilities. Disposai - what are the choices? Most non-hazardous liquids can be discharged di- rectly into the sewer if the municipal sewage system has adequate treatment capacity to handle the wastes. If not, or if the generator is not connected to a sewer system, they must be trucked to a water pollution control plant for treatment. About 50 per cent of the wastes treated off-site are non-hazardous liquids that are processed in this way. A substantial proportion of these are leachates - liquids that collect in landfill sites - that must be trucked to the water pollution control plants because of the lack of a direct sewer connection. 87 waste management continued Hazardous wastes, on the other hand, usually re- quire more complex and specialized treatment. Some substances can be made harmless and then disposed of by conventional means. Strong acids and caustic liquids, for example, can be neutralized. Some others can be broken down through chemical or biological processes. Other materials, however, must be disposed of in one of the foD owing ways: Landfilling. Sludges from petroleum refining and other industrial processes are often disposed of in this way. However, care must be taken to prevent contaminated liquids from leaching into the sur- rounding soil and groundwater. In landfills for haz- ardous wastes, this is accomplished by the use of natural or synthetic liners to contain the leachate and a leachate collection system to pump it out Some wastes may also be pretreated or solidified to make them easier to handle or less susceptible to leaching. Incineration. High-temperature incineration is the only effective way of destroying some hazardous substances, such as high-level PCBs. Specially de- signed incinerators can achieve 99.9999 per cent destruction of these wastes, but careful controls are needed to prevent the release of dangerous gases or particles, and any ash that is left over must be buried in a secure landfjlL Export. Hazardous and liquid industrial wastes are also shipped out of the province for disposal else- where, usually in New York or Michigan. In some cases, this is done because adequate disposal facili- ties for certain wastes (e.g., organic sludges and chlorin-ated organic chemicals like CFCs and some pesticides) are unavailable in Ontario. In other cas- es, it may be safer and more economical to use a treatment facility closer to the generator, even though it is in another jurisdiction. For the same reasons, wastes from other jurisdictions are also shipped into Ontario for disposal. Both Canada and the United States, however, prohibit the impor- tation of PCBs. Storage. Hazardous wastes awaiting destruction or for which there is no satisfactory disposal method must be kept in secure storage. Secure storage, how- ever, involves some risk of fire or spillage and is therefore an unacceptable method for long-term disposal. Thousands of tonnes of PCB wastes are now in storage in Ontario because of uncertainty over the best method of destroying them. Wastes contaminated with low levels of PCBs are now be- ing destroyed using mobile incinerators. Recycling and reusing. This is one of the most de- sirable ways of handling wastes because it reduces the need for disposal, causes less environmental contamination and reduces the demand on natural resources. Waste oils, solvents, antifreeze and metal finishing sludges are commonly recycled materials. Dust suppression. Some non-hazardous industrial liquid wastes have also been approved by the min- istry for use as dust suppressants. A liquid waste from the pulp and paper industry, for example, is suitable for use on roads, while waste oil from steel mills and thermal-electric power stations is some- times used on coal storage piles. All of these sup- pressants must be used in a controlled fashion, however, since improper application can harm veg- etation and pollute surface and ground waters. Figure 13.3 shows the quantity of wastes receiving final disposal by these methods in 1992. Because landfill leachates make up about half of the hazardous and liq- uid industrial wastes sent for off-site disposal, treatment at water pollution control plants is the largest disposal "1 category. For other hazardous wastes, export and land- filling are the most used disposal options and incinera- tion the least. Storage is not shown here because it is not a final disposal option. Can nil the was&s produced ba hawSad? In 1986, when MOEE began tracking hazardous and liquid industrial wastes, some 840,000 tonnes were shipped off site for disposal. By 1990 that amount had grown to nearly 1.5 million tonnes (Figure 13.4). In part, this growth reflects an increase in compliance with the regulations as the program became established, but waste generation also tends to follow the fortunes of the economy. Thus, after growing by an average of more than 10 per cent a year from 1987 to 1990, the output of waste declined moderately in 1991 as the economy went into recession. However, as economic conditions im- prove, we can expect the output of hazardous and liquid industrial wastes to increase once again. More waste, however, means a greater demand on disposal facilities. At the moment, Ontario has only one commercial landfill for hazardous and solidified liquid industrial waste. At the present rate of use, this capacity will be exhausted by 1996 or 1997, at which point addi- tional facilities will be required. Most of the incineration of hazardous and liquid industrial wastes in Ontario is carried out at a liquid waste incinerator near Sarnia. However, this facility can- not handle solids, sludges, or chlorinated organic chemi- cals, which are making up an increasing portion of the hazardous waste stream. Destruction of these materials requires the use of a rotary kiln incinerator. At the mo- ment, this equipment is not available in Ontario and these wastes must be sent out of province for disposal. waste management continued Rgure 13.3: Receivers of hazardous and mqu1b {{«dustjuai waste, 1992 ■H| Land Bed MilBons of tonnes "ijà t.o "as" ae 0.4 0.2 6" 1387 13SÊ 1939 1S90 1931 Figure 13.4: Amount of hazardous and liquid industrial WASTE SHlPm> FOR OFF-SfFE DISPOSAL, 1987-1992 thousands of tonnes 12133 1000 800 ~BÔÔ 400 200 6'" Biomedical wastes are another problem. Currently, about 60 per cent of these wastes are sent either to Que- bec or the United States for disposal. The remainder are destroyed locally in small hospital incinerators. How- ever, as these lack modern air pollution control equip- ment, they are being phased out of operation. The Ministry of Environment and Energy and the Ministry of Health, in cooperation with the Ontario Hospital Association, have developed plans to replace these incin- erators with regional biomedical waste disposal facilities. waste management continued Figure 13.5: Imposts and exports of hazardous and uouro ÎNDOSTRiAt WASTE, 19*7-1992 Thousands of tonnes 200 ■■jknpcn «ÏJ&port Figure 13.6: Number of PCB v&ste storage sites, 1981- 1992 Number of sites 200O In 1987, only about Ave per cent of Ontario's haz- ardous and liquid industrial wastes were shipped out of province for disposal. By 1991 these exports had grown to 17 per cent, or about 166,000 tonnes (Figure 13.5). The largest component, about a third of the total, was waste oil exported to processors and reclaimers in the United States. In part, the increase in exports may be driven by economic factors or convenience. But it also reflects the fact that Ontario does not have facilities for treating chlorinated organic wastes, organic sludges and certain other hazardous wastes that are making up a growing proportion of the hazardous waste stream. Imports, on the other hand, have declined slightly. In 1992, they totalled approximately 95,000 tonnes, with about half coming from the United States and half from other provinces. About 54 per cent of the import total was waste oil destined for recycling. Exports and imports are of concern if they increase the amount of transportation and handling of haz- ardous wastes. However, transborder shipment can also involve the shortest travelling distances and increase the safety of handling. In the longer term, an excessive re- liance on exports for disposal could be a problem if au- thorities in other provinces or states decide to close their borders to incoming wastes. Although such a ban is unlikely for most of the ma- terials now shipped out of Ontario, the United States has forbidden the importation of PCBs since 1982. Because Ontario does not have adequate destruction facilities for most PCB wastes, Ontario has been left with the unsatis- factory option of placing these in storage until it is pos- sible to dispose of them. Over the past decade the number of storage sites has increased dramatically, from a mere handful in 1981to 1751 sites at the end of 1992 (Figure 13.6). All these wastes are stored on the proper- ties of their owners, since there are no approved com- mercial PCB storage sites in the province. Mobile incinerators have been used to destroy some of these wastes, and more than 15,000,000 litres of cont- aminated mineral oil have been disposed of in this way. However, Ontario has not yet approved these facilities for the destruction of more concentrated PCB wastes. At the end of 1992, there were still about 1 13,000 tonnes of these wastes in storage in Ontario, and until more de- struction facilities are set up that quantity will continue to increase as old transformers and other equipment and materials containing PCBs are taken out of service. SO New environmental regulations are expected to fur- ther increase the gap between waste management capa- bilities and requirements. The phasing out of CFCs, for example, will eventually require the treatment of 40 000 tonnes of these chemicals. Tighter controls on munici- pal sewage and industrial effluent and on landfiling will also divert more materials to the hazardous waste stream. Ontario currently does not have facilities to deal with hazardous wastes that must now be exported or stored, nor to meet future disposal requirements. One option would be to build a single integrated hazardous waste disposal facility which would serve the whole province. A proposal for such a facility, to be built and operated by the Ontario Waste Management Corpora- tion, is now in the environmental assessment process Household hazardous wastes The average household also generates a small but significant amount of hazardous waste - about 2.5 kg per person, according to one estimate. This includes items such as solvents, cleaners, pesticides, paint batter- ies, pool chemicals, propane tanks and many other com- mon household articles. Because many of these items are not recognized as hazardous, they often end up in ordinary household garbage or are poured down the sewer. About 250,000,000 litres of used lubricating oil, for example, are improperly disposed of every year in Canada. Many municipalities are now beginning to inform the public about household hazardous wastes and to provide a disposal system for them. Some municipalities have established centres where household hazardous wastes can be dropped off. Others have set up special collection days or pickup services. Since the first of these waste management continued FrGUSE 13.7: Amount of household hazardous waste COLLECTED, 1986-87 TO 1992-93 Tonnes diverted 150O 1200 '" 90O éoo 30O 'B6-'S7 B7-'B8 B8--B9 -89--90 "9031 31 -'92 "SS-^S ... . [esc] Fscsi yea- programs was established in the mid-1980s, their use has grown considerably. The dramatic increase in the amount collected in 1989-90 was due to the establish- ment of 10 permanent depots in the Metropolitan Toronto area and several others elsewhere (Figure 13.7). During the 1992-93 fiscal year, more than 1600 tonnes of household hazardous wastes were collected for proper disposal. However, estimates suggest that Ontario generates more than 20 000 tonnes of these wastes every year. A good start has been made, but obvi- ously there is some way to go before most household hazardous wastes are managed properly. Problems from the past Until the late 1970s, the disposal of hazardous and liquid industrial wastes generally was not adequately controlled. In the United States, toxic substances from abandoned chemical dumps have caused serious water and soil contamination. In 1978, in one of the most no- torious of these incidents, more than 1,000 homes near Niagara Falls, New York, had to be evacuated because of contamination from the nearby Love Canal disposal site. 9' waste management continued In Ontario, hazardous wastes have been found in some of the province's 2,400 closed landfills, but moni- toring of these sites has not shown any spread of conta- mination. A potentially more serious problem is the presence of buried coal tar wastes on sites formerly oc- cupied by coal gasification plants. Until the 1950s, when the use of natural gas became widespread in Ontario, these plants produced gas from coal for both residential and industrial purposes. Buried coal tar wastes may be harmless if left undis- turbed, but in some cases they may contaminate groundwater supplies. If disturbed by construction, they can contaminate surface waters and they may pose a short-term health risk to workers. Long-term exposure may increase the risk of skin and respiratory cancers. Altogether, the ministry has identified 41 municipal and 44 industrial coal gasification sites. Where a hazard exists, the owners of the site are required to remove the wastes and contaminated soil to an approved disposal facility. The ministry must also be advised before any work can be undertaken that might disturb the site. dm Ontario do better? Reducing, recycling, reusing The more hazardous waste that is produced, the more need there is to expand disposal capabilities. That means an increasing demand for secure landfills, spe- cialized incinerators and other treatment facilities. How- ever, setting up these facilities takes time and money and many communities are reluctant to have them nearby. To reduce the need for such facilities and still maintain the capacity to manage these wastes, as much as possible must be done to reduce the amounts sent for disposal. One way of handling this problem is to reduce the amount of waste that is produced in the first place. This can sometimes be done through changes in production materials and technologies, although the amount of waste produced by industry as a whole is already very small - less than one per cent of total production - and only about 10 per cent of that amount is hazardous. There may be more scope, though, for recycling and reuse. A study by Environment Canada in 1986 estimat- ed that about half the hazardous wastes produced in Canada had a high potential for recycling. However, off- site recycling accounted for only about 6.5 per cent of Ontario's hazardous and liquid industrial wastes in 1992 and there has been no increase in this proportion over the past decade. Of course, many companies build recy- cling and reuse into their production processes, but be- cause MOEE does not track wastes that are managed on site there is no way of knowing how much on-site recy- cling takes place or whether the proportion is increasing or decreasing. In order to increase opportunities for off-site recy- cling, the Ontario Waste Exchange was established in 1978. Based on the premise that waste from one compa- ny may be usable as a raw material by another, it pro- vides a means for waste generators and potential users to make contact During the 1991-92 fiscal year, the ex- change diverted almost 82,000 tonnes of hazardous and non-hazardous waste from disposal. Makers of items that eventually end up as haz- ardous waste are also being urged to assist in the dispos- al of their products. The Canadian Petroleum Products Institute, for example, recently set up a network of de- pots for the collection of used oil from consumers. MOEE is now discussing similar arrangements with oth- er industry groups for the disposal of paints, batteries, and pharmaceuticals. waste management continued At the present time, Ontario is able to cope satisfac- torily with most of the hazardous and liquid industrial wastes it now produces. But some important capacity problems must still be resolved, particularly: the need for a new secure landfill to replace the Sar- nu site when it is exhausted; the need for additional treatment, destruction and disposal capacity to handle PCBs now in storage and future requirements, such as the destruction of CFCs, that will arise out of new regulatory require- ments; Over the longer term, however, maximizing the re- duction, reuse and recycling of hazardous and liquid industrial wastes not only will reduce the demand for disposal capacity but is the most environmentally benign way of dealing with these materials. 93 fterword The preparation of this report marks the first time the Ministry of Environment and Energy has brought to- gether information from across the ministry. The data has been presented as clearly and accurately as possible. 5t is our hope that the information contained in this re- port informs you about specific environmental condi- tions in Ontario of interest to you and expands your general knowledge and appreciation of the complexity of the environment. From the Ministry's perspective, this project has helped us to appreciate the value, and limitations, of the data that we gather. It has tested our ability to draw a bigger picture from the hundreds of very specific indica- tors which we monitor, and has helped us identify gaps in our monitoring and reporting programs. As we turn our thoughts and energy to the develop- ment of Ontario's next State of the Environment Report, we will evaluate how we can improve on this report To do this, we need your feedback. We would like your evaluation of this report and your comments and suggestions on what you would like to see in Ontario's next State of the Environment report. You can fill out and return the survey on the next page, or send your own written comments to: Communications Branch Ministry of Environment and Energy 135 St Clair Avenue West Toronto, Ontario M4V 1P5 95 endings Air Ministry of Environment and Energy. 1992 Air Quality in Ontario. 1993. Ministry of Environment Air Quality Monitoring Studies in -aie Sudbury Area, 1978 to 1988. March 1992 Fraser, D. , ïap, D., Kiely, P. and Mignacca, D. Analysis of Persistent Ozone Episodes in Southern Ontario 1980-1991. Technology Transfer Conference Toronto Proceedings: pp 222-227. 1991. Heidorn, K.C and Yip, D. A Synoptic Climatology For Surface Ozone Concentrations in Southern Ontario, 1976-1981. Atmospheric Environment Vol. 20 No. 4, pp 695-703. 1984. Ministry of the Environment, Scientific Criteria Docu- ment for Standard Development No 4-84; Polychlorinated Dibenzo-p-dioxins (PCDDs) and Polychlorinated Diben- zofurans (PCDFs). 1985. Regulation Respecting Control of Exposure to Biological or Chemical Agents - made under the Occupational Health and Safety Act - Ontario Regulation 654/86. Acid Rain BEAK Consultants for MOEE. Ontario Hardwood DecEne Survey 1989 and 1990. 1992. DiBon, P.J., R-A. Reid and E de Grosbois. 1987. The rate of acidification of aquatic ecosystems in Ontario, Canada. Nature, 329:45-48. Keko, J.M.R., and D.S. Jeffries. Response of headwater lakes to varying atmospheric deposition m north-central Ontario, 1979 to 1983. Tournai of Fisheries and Aquatic Sciences: vol 45, p. 1905 1988. Matuszek, J.E, and G.L Beggs. Fish Species in Relation to Lake Area, pH, and Other Abiotic Factors in Ontario Lakes. Canadian Journal of Fish and Aquatic Science: voL45,pp. 1931-1941. 1988. McLaughlin, D.L, MOEE. Etiology of Sugar Maple Decline at Selected Sites in Ontario (1984-1990). 1992. Neary, B.P., P.J. Dillon, J.R. Munro, B.J. Clark, MOEE. The acidification of Ontario lakes: An assessment of their sensitivity and current status with respect to biological damage. 1990. Neary, B.P. and P.J. Dillon. Effects of sulphur deposition on lake-water chemistry in Ontario, Canada. Nature 333: 340. 1988. Federal/Provincial Research and Monitoring Coordinating Committee, Environment Canada. The 1990 Canadian long-range transport of air pollutants and acid deposition study. 1990. Water quality Gênerai Canadian Council of Resource and Environment Ministers. Canadian Water Quality Guidelines. 1987. Government of Ontario. Water quantity resources of Ontario. 1984. Griffiths, R-, MOEE. BioMap: concepts, protocols and sampling procedures for the southwestern region of Ontario. 1993. Ministry of Environment and Energy. Our shared resource: Towards a provincial water policy framework for Ontario. Revised Draft May 1993. Ministry of the Environment Water management - goals, policies, objectives and implementation procedures of the Ministry of the Environment Revised 1984. further readings continued Royal Commission on the Future of Toronto's Water- front Pathways: Towards an ecosystem approach. VoL 1 1. 1991. inland Lakes Dillon, P.J., W.A. Scheider, R-A. Reid and D.S. Jeffries, MOEE. The Lakeshore Capacity Study. Part I: A test of the effects of shoreline development on the trophic status of lakes. 1992. Ministry of Environment and Energy. Cottagers' self-help program enrichment status of lakes in the southeastern region of Ontario 1992. August 1993. Ministry of Environment and Ministry of Natural Resources. 1993 Guide to eating Ontario sport fish 1993. Ministry of Environment and Energy and Ministry of Natural Resources. Inland lake trout management in southeastern Ontario. January 1993. Neary, B.P. and B.J. Clark, MOEE The chemical water quality of Lake Nipissing 1988- 1990. 1992. Reid, R.A. and S.M David, MOEL Crayfish distribution and species composition in Muskoka and Haliburton lakes. 1990. Yan, N.D. and RM. Welbourn. 1990. The impoverishment of aquatic communities by smelter activities near Sudbury, Canada. In Woodwell, G.M (éd.). The Earth in Transi- tion: Patterns and processes of biotic impoverishment Cambridge University Press, pp. 477-494. Graat Lake*; Government of Ontario. Restoring and protecting the Great Lakes: 1991 Progress report. 1993. Great Lakes Water Quality Board. J989 report on Great Lakes water quality. Report to the International Joint Commission. October 1989. Howell, ET, MOEE. Great Lakes long-term sensing sites: Preliminary results for ate Niagara River corridor stations. February 1993 International Joint Commission. Cleaning up our Great Lakes: A report from the Water Quality Board to the Inter- national Joint Commission on Toxic Substances in the Great Lakes Basin Ecosystem. 1991. International Joint Commission. Review and evaluation of the Great Lakes remedial action plan program. Great Lakes Water Quality Board report to the International Joint Commission. 1991. Krantzberg, G., MOEE. The influence of the oxygen regime in the water column on the toxicity of Hamilton Harbour sediment 1992. Krantzberg, G. and Boyd, D. The biological significance of contaminants in sediment from Hamilton Harbour, Lake Ontario. Environmental Toxicology and Chemistry. vol. 11, pp. 1525-1538. 1992. Nichofls, Kenneth H. and Gordon G. Hopkins. Recent changes in Lake Erie phytoplankton: Cumulative impacts of phosphorus loading reductions and the zebra mussel introduction. Journal of Great Lakes Resources: vol. 19, pp. 637-647. 1993. 1993 Report of the Great Lakes Water Quality Board to the International Joint Commission. International Joint Commission. September 1993. Richman, LA., MOEE. Niagara River biomonitoring study, 1989. Summary Report submitted to the Niagara River Toxics Management Plan Secretariat for inclusion in its 50% Loading Reduction Report March 1992. Richman, LA., MOEE. The Niagara River mussel and leech biomonitoring. 1992. Richman, LA., MOEE. Preliminary technical report Summary of the 1991 Niagara River mussel biomonitoring survey. 1993. m further readings continued Smith, I.R., MOEE 1991 Peninsula Harbour sediment study. March 1993. Smith, I.R State of the Lake Superior basin reporting series volume IL Draft stage 1 lakewide management plan. Ontario Ministry of Environment and Energy, Ontario Ministry of Natural Resources, and U.S. Fish and Wildlife Service, October 1993. Smith, J. and Smith, I., MOEE and Environment Canada. Yardsticks for assessing the water quality of Lake Superior. March 1993. Snodgrass, W.J. and D'Andréa, M. Dry weather dis- charges to the Metropolitan Toronto waterfront Remedial Action Plan Report, Environment Canada and the Ontario Ministry of Environment and Energy. April 1993. Suns, K.R, MOEE Organochlorine Contaminant Trends in Niagara River Spottail Shiners. Report prepared for the Niagara River Toxics Management Plan Secretariat September 1992. Suns, K. R, G. G. Hitchin, and D. Toner. Spatial and temporal trends of organochlorine contaminants in spot- tail shiner from selected sites in the Great Lakes (1975- 1990). Journal of Great Lakes Resources. 19:703-714. 1993. Tarandus Associates Limited. 1993. Great Lakes Long- Term Sensing Sites: The Evaluation of Water, Sediment and Benthic Invertebrates from Stations in Lake Ontario and Niagara River Corridor in 1 990. Prepared for the Ontario Ministry of Environment and Energy, October 1993 (awaiting publication approval). Tarandus Associates Limited. 1993. Great Lakes embay- ments and harbours investigation program, phase I: The Lake Erie harbours synoptic surveys. Prepared for the Ontario Ministry of Environment and Energy, March 1993 (awaiting publication approval). Remédiai Action Plans Thunder Bay Remedial Action Plan Stage 1 Report Envi- ronmental Conditions and Problem Definition. October 1991. Nipigon Bay Remedial Action Plan Stage 1 Report: Envi- ronmental Conditions and Problem Definition. October 1991. Jackfish Bay Remedial Action Plan Stage 1 Report: Envi- ronmental Conditions and Problem Definition. October 1991. Peninsula Harbour Remedial Action Plan Stage 1 Report Environmental Conditions and Problem Definition. October 1991. St Marys River Stage 1 RAP - Environmental Conditions and Problem Definitions, May 1992. Spanish Harbour Stage 1: Environmental Conditions and Problem Definition. November 1993. Severn Sound Remedial Action Plan Stage 2 Report April 1993. Severn Sound Remedial Action Plan Stage 1 - Environ- mental Conditions and Problem Definition. February 1989. CoUingwood Harbour Remedial Action Plan, Stage 1: En- vironmental Conditions and Problem Definition. March 1989. The CoUingwood Harbour Stage 2 Document a delisting strategy. August 1992. St Clair River RAP Stage 1 Update ( 1st Draft) - March 1993 Detroit River Remedial Action Plan - Stage 1 - June 1991. Niagara River Stage 1 Report Environmental Conditions and Problem Definitions, October 1993 S3 further* readings continued Chemicals of Concern in Niagara River Tributaries 1988- 89, Niagara River Improvement Project, Ontario Ministry of Environment and Energy, July 1993. Stage 1 Report Remedial Action Plan for Hamilton Har- bour Environmental Conditions and Problem Definition. March 1989. The Remedial Action Plan (RAP) for Hamilton Harbour - Stage 2A. July 1991. Hamilton Harbour Final Stage 2 Report (to COA RAP Steering Committee). November 1992. Stage l:Metropolitan Toronto Environmental Conditions and Problem Definition. May 1989. Metropolitan Toronto Remedial Action Plan: Strategies for Restoring Our Waters. December 1991. Port Hope Harbour Remedial Action Plan Stage 1: Envi- ronmental Conditions and Problem Definition. January 1990. Stage 1, Bay of Quinte: Environmental Setting and Prob- lem Definition. July 1990. Bay of Quinte RAP Stage 2 Report September 1993. St Lawrence River Area of Concern Remedial Action Plan for the Cornwall- Lake St Francis Area Stage 1 Report Environmental Conditions and Problem Definition August 1992. Groundwater Environment Ontario. 1987. Water wells and groundwa- ter supplies in Ontario. ISBN 0-7729-1010-3. Revised 1987. Drinking Water Drinking Water Surveillance Program, Annual Report 1 991/92, Ontario Ministry of the Environment 1994 Ontario Drinking Water Objectives Information Sheet Summer 1992, Ontario Ministry of Environment and Energy Parameters Listing System (PALIS).Hev)sed, October 1992. Ontario Ministry of the Environment. Queen's Printer for Ontario, 1992 Pesticides in Ontario Municipal Drinking Water - 1988. September 1990. Ontario Ministry of the Environment Queen's Printer for Ontario, 1990 Drinking Water Information Sheet Summer 1990. Ministry of the Environment About Water Treatment Plant Operation Fact Sheet (WFS8). Ministry of the Environment Ontario's Drinking Water Surveillance Program Informa- tion Sheet, Winter 1992. Ministry of the Environment Waste Management Municipal Soiki Waste Greater Toronto Area 3Rs Analysis, EA Input Document M.M. Dillon Ltd for the Ontario Ministry of Environ- ment and Energy. Draft November 1993. Queen's Print- er for Ontario, 1993. Interim Guidelines for the Production and Use of Aerobic Compost in Ontario Ontario Ministry of the Environ- ment Toronto: Queen's Printer, November 1991. 100 Market Assessment of 3R's Activities in Ontario. Re- sources Integration Systems Ltd for the Ontario Min- istry of the Environment. Queen's Printer for Ontario, 1992. Meeting the Challenge: Reduction and Recycling Activities in the Greater Toronto Area. Ontario Ministry of the Environment Toronto: Queen's Printer, 1992. Municipal Waste Management Powers in Ontario. On- tario Ministry of Municipal Affairs. Toronto: Queen's Printer, March 1991 National Packaging Protocol Results of the 1990 National Packaging Survey. National Task Force on Packaging, December 1992. OMMRI — Corporations in Support of Recycling: Overview. Ontario Multi- Material Recycling Incorporat- ed. Toronto: OMMRI, August, 1992. Ontario Waste Composition Study. Gore and Storrie Ltd. December 1991. The Physical and Economic Dimensions of Municipal Sol- id Waste Management in Ontario. CH2M Hill Engineer- ing Ltd. and MacLaren Engineers for the Ontario Min- istry of the Environment, November 1991. Queen's Printer for Ontario. Regulatory Measures to Achieve Ontario's Waste Reduc- tion Targets: Initiatives Paper No. 1. Ontario Ministry of the Environment Toronto: Queen's Printer, October 1991. A Socio-Economic Assessment of Ontario Waste Manage- ment Initiatives. VHB Research and Consulting Inc. for the Ontario Ministry of the Environment. Queen's Printer for Ontario, January 1993. further readings continued True Cost of Municipal Waste Management VHB Research & Consulting Inc. for the Ontario Ministry of the Environment. Queen's Printer for Ontario, 1993. The Waste Crisis in the Greater Toronto Area: A Provincial Strategy for Action. Ministry of the Environment and the Office of the Greater Toronto Area. June 1991, Toronto. Waste Management Planning in Ontario: Initiatives Paper No. 2. Ontario Ministry of the Environment. Toronto: Queen's Printer, March 1992. Hazardous and liquid todus&riai Waste 1991 Ontario Waste Exchange Directory. Ontario Re- search and Technology Foundation (ORTECH). Toron- to: ORTECH International, 1991. Ministry of Environment and Energy Annual Hazardous Waste Public Information Data Set, June 1992. Practical Guide for Sampling Waste and Industrial Processes. Ontario Waste Management Corporation, Toronto, 1993. Ontario Waste Management Corporation Waste Reduc- tion Bulletin - Profiles of industrial 3Rs success stories and pollution prevention technologies, (published 3/year). Pollution Prevention for the Great Lakes: Tips for Small Quantity Hazardous Waste Generators, LURA Group for Environment Canada. Toronto, 1991. Canada's Present Day and Future Hazardous Waste Management Facilities. Man-West Environmental Group Ltd., Winnipeg, June 1993. 101