I U 1 i FOLIAGE CHEMISTRY IN THE VICINITY OF ALLIED CHEMICALS CANADA INC AND GENERAL CHEMICAL CANADA LTD AMHERSTBURG, ONTARIO IN 1988, 1989 AND 1990 SEPTEMBER 1991 Environment Environnement Ontario ISBN 0-7729-8863-3 FOLIAGE CHEMISTRY SURVEYS IN THE VICINITY OF ALLIED CHEMICALS CANADA INCORPORATED AND GENERAL CHEMICAL CANADA LIMITED AMHERSTBURG, ONTARIO IN 1988, 1989 AND 1990 Report prepared by: William I. Gizyn Phytotoxicology Section Air Resources Branch Ontario Ministry of the Environment SEPTEMBER 1991 Cette publication technique n'est disponible qu'en anglais. Copyright: Queen's Printer for Ontario, 1991 This publication may be reproduced for non- commercial purposes with appropriate attribution. PIBS 1678 log 91-2231-079 Table of Contents 1 Introduction 1 2 Previous Phytotoxicology Section Surveys 2 3 Phytotoxicology Surveys in 1988, 1989 and 1990 2 3 . 1 Silver Maple Survey 3 3.1.1 Fluoride in Unwashed Silver Maple Foliage 4 3.1.2 Fluoride in Washed Silver Maple Foliage 5 3.1.3 Sodium in Unwashed Silver Maple Foliage 5 3.1.4 Chlorine in Unwashed Silver Maple Foliage 6 3.1.5 Long Term Concentration Trends 7 3.1.6 Foliar Injury Observations 8 3 . 2 Complaint Investigations 8 3 . 3 Cottonwood Survey 9 3.3.1 Fluoride in Cottonwood Foliage 10 3.3.2 Sodium in Cottonwood Foliage 12 3.3.3 Chlorine in Cottonwood Foliage 14 4 Fluoride Candle Monitoring 14 5 Suspended Particulate Monitoring 16 5 Summary and Conclusions 17 6.1 Allied Chemicals Canada Incorporated 18 6.2 General Chemical Canada Limited 19 7 Figures 21 8 Appendix 1: Silver Maple Foliage Concentrations 36 9 Appendix 2: Cottonwood Foliage Concentrations' 38 10 Appendix 3: Fluoridation Rates, 1975 to 1990 40 1 Introduction Allied Chemicals Company Incorporated (ACCI) and General Chemical Company Limited (GCCL) operate chemical production plants immediately north of the town of Amherstburg in south- western Ontario. While these companies are discrete corporate entities, they occupy a common industrial property, and were one company. Allied Chemical Company Limited, prior to 1986. According to an Allied Chemical Company Limited information brochure, the primary production facilities of what are now these two companies, occupy a site of approximately 500 acres. This does not include various quarry and brine well properties. This site, which will be referred to as the "industrial complex", is bordered on the west by Highway 18 and the Detroit River, and on che east by other industrial and agricultural lands. Lands to the north consist of vacant fields, scrub bush and agricultural fields. However, residential properties are located immediately north of these lands. Distances between the indus- trial complex fence line and these residential properties are on the order of 200 metres. The southern boundary of the industrial complex is shared by agricultural fields, other industrial properties and, in the western portion, by residential properties of the town of Amherstburg . ACCI produces hydrofluoric acid and chlorof luorocarbons . GCCL produces sodium carbonate and calcium chloride. Raw materi- als, products and by-products involved in the industrial pro- cesses employed by both companies include both common and exclusive chemical elements. Both companies handle calcium and chlorine compounds. However, sodium is involved only in GCCL pro- cesses and fluorine only in ACCI processes. While it is the usual practice of the Phytotoxicology Sec- tion to report on surveys around industrial sources in separate and distinct reports, there is sufficient justification to combine these two assessments in a common report. Such justifica- tion includes: 1. Common elements in industrial processes with potential of environmental contamination by these elements by either com- pany 2 . Common operating site 3. Previously one company 4 . Common sampling stations in Phytotoxicology survey 5. Report is public document 2 Previous Phytotoxicology Section Surveys The Phytotoxicology Section of the Air Resources Branch has been actively monitoring contamination of vegetation by emissions from these industrial sources. The report "Phytotoxicology Assessment Survey Investigation in the Vicinity of Allied Chemi- cal Canada Limited and General Chemical Canada Limited, Amherst- burg, Ontario - 1987" contains details regarding the industries, the nature of previous Phytotoxicology surveys, and analyses of current (1987) data as well as data trends in time through the use of historic data. This report will be referred to as the "1987 report". Since much of the information will not be repeated here, the reader is advised to consult the 1987 report for background information . Other monitoring activities, conducted by the Ministry in the vicinity of the complex consist of a network of fluoridation candles and a suspended particulate sampler. Two additional sus- pended particulate samplers were established in early 1991 to monitor particulate emissions from the complex. These monitoring activities will be discussed later in this report. 3 Phytotoxicology Surveys in 1988, 1989 and 1990 This report will describe the nature of survey activities conducted in 1988 to 1990, present the results of these surveys and offer analysis and interpretation. There were two distinct survey designs utilized during the period from 1988 to 1990. The first was a continuation of sam- pling of silver maple foliage from long-established survey sta- tions. The second consisted of a new network of sites at which foliage from cottonwood trees was collected. 3 . 1 Silver Maple Survey The design of this survey was fully described in the 1987 report. Briefly, the survey consisted of nine stations (trees) which were visited five times during the growing season, at the ends of the months of May through September. Triplicate samples of foliage were taken from the sides of silver maple {Acer sac- charinum) trees facing the industrial complex. In 1988, this survey was continued with samples being taken at end of the months of May and June. However, a Ministry wide fiscal restraint curtailed all Phytotoxicology survey activity for the remainder of 1988. Consequently, only two sets of sam- ples were obtained. In 1989, survey resources were directed to the new survey design described below. However, two visits to the maple sta- tions at the ends of the months of July and August (actually Sept. 5) were conducted to maintain some continuity in the data base for the silver maple stations. The collection, sample processing and chemical analysis pro- cedures employed in 1988 and 1989 were identical to those employed previously. There was one change made in the station configuration. Namely, Station 65 was discontinued because it could potentially be influenced by another industrial source in the area. Station 15 was established as a new, more distant con- trol station. The locations of these stations are represented in the map comprising Figure 1. The results of the chemical analyses of the samples are given in Appendix 1, along with the arithmetic means and standard deviations of the triplicates. Note that the analytes consist of sodium, chlorine, calcium and fluoride. Fluoride was determined in both washed and unwashed tissue. Because the method of analysis reports total concentrations of the elements sodium, chlorine and calcium, references to these analytes will be by their element name. How- ever, since fluoride concentrations are determined on a weak acid extraction of the tissue by ion electrode, reference to this analyte will be by the ion name, fluoride. Under no circum- stances is it inferred that the reactive gases Clj or F2 are involved in any of the foliar chemistry results. The means of the triplicate samples collected in 1988 and 1989 at the nine stations are graphically represented in Figures 2 through 5. These figures represent concentrations of fluoride in unwashed and washed tissue as well as sodium and chlorine in unwashed tissue. Calcium concentrations, although presented in Appendix 1, are not graphed. Although calcium compounds are utilized by both companies, GCCL personnel have acknowledged that emissions can be attributed primarily to the lime kilns operated by their com- pany. However, the naturally high background concentrations in foliar tissue precludes foliage chemistry as a viable method to assess calcium emissions to the air. Consequently, calcium data will not be discussed in this report. Following are discussions of the 1988 and 1989 silver maple foliage chemical data. 3.1.1 Fluoride in Unwashed Silver Maple Foliage The concentrations of fluoride in exposed, unwashed silver maple foliage (Figure 2) display a wide range. The relative concentrations between stations, when examined against the backdrop of the station locations, identifies the industrial complex as the source area. Since GCCL does not manufacture or utilize compounds containing fluoride, emissions and contamina- tion of the foliage can be ascribed to ACCI . Concentrations at the same station can change significantly in the period of one month. Evidence of this is seen in the Station 16 data for July and August, 1989 samples. Fluoride concentrations in silver maple tissue well removed from an industrial source, such as at Station 15, are on the order of five micrograms per gram (ug/g) . Stations close to the source, and presumably downwind for a period of time before sampling, are contaminated with concentrations for most sites in excess of 50 ug/g and as high as 200 ug/g. Although the limited and unsynchronized sampling programs in 1988 and 1989 precludes direct comparison, generally, con- centrations encountered in the 1989 samples appear lower than those of 1988. The concencrations encountered can be compared to Phytotox- icology Upper Limits of Normal Guidelines (ULN) . These guide- lines represent the highest concentrations that should be encountered in foliage samples that are not influenced by industrial sources in close proximity. These guidelines, which are 15 ug/g for rural samples and 35 ug/g for urban samples, were routinely exceeded in samples taken in the vicinity of the ACCI operation. While ULN guidelines are not enforceable as standards, the consistency and degree with which they continue to be exceeded represents a potential for injury to sensitive plant species and warrants further assessment of controls on known sources of emissions as well as an investigation of all potential fugitive sources within the ACCI operation. 3.1.2 Fluoride in Washed Silver Maple Foliage Fluoride in washed silver maple foliage is represented in Figure 3. These data parallel those of the companion unwashed samples; however, the absolute concentrations are lower. This indicates that some of the fluoride is either on the surface of the foliage, or was leached from the foliage in the washing process. Since significant amounts of fluoride are taken into the plant tissue, the potential for injury of foliar tissue is of concern. Washing of foliage prior to fluoride analysis was also per- formed for historic reasons. Control Orders were in place in the 1970' s which required limiting fluoride concentrations in washed silver maple foliage. The limit was 100 ug/g. The con- centrations in the May and June, 1988 samples from Station 1; and the June, 1988 samples from Station 16 exceeded the former Control Order limits. It is notable that none of the 1989 sam- ples exceeded this limit. 3.1.3 Sodium in Unwashed Silver Maple Foliage Sodium releases to the atmosphere are attributable to GCCL since ACCI does not utilize or produce compounds containing this element. Sodium concentrations in silver maple are repre- sented in Figure 4. As with fluoride, concentrations of sodium display a wide range. The highest concentrations were encountered at Stations 16, 18 and 31. Considering that pre- vailing winds are from the south to southwest, contamination of foliage at Station 31 is consistent with emissions from GCCL . Stations 16 and 18 are upwind of the prevailing winds, but are the closest stations to the GCCL operation. It should be noted that winds can and do blow from all directions at some time. Consequently, the contamination at these stations is also con- sistent with emissions from GCCL. The Phytotoxicology ULN guidelines for sodium in tree foliage are 50 ug/g in rural samples and 350 ug/g in urban samples. The only station where the rural guideline is not exceeded is the control Station 15. The urban guideline was exceeded regularly at Stations 16, 18 and 31. The highest con- centration was 787 ug/g at Station 31 in May, 1988. This con- centration is typical of those encountered in 1987, but considerably less than the 1700 ug/g also seen in 1987. (See Figure 4 in 1987 report) It should also be noted that, subject to the intercompari- son limitations, the -1989 concentrations appear to be lower than the 1988 concentrations. However, the ULN guidelines were still exceeded. 3.1.4 Chlorine in Unwashed Silver Maple Foliage Figure 5 represents the chlorine concentrations encountered in 1988 and 1989. The most notable difference between these data and those for fluoride and sodium is the relatively small differences in concentrations between the stations close to the source and those at greater distances. For example, sodium con- centrations at the more impacted stations are an order of mag- nitude higher than the control station concentrations, while, differences in chlorine amount only to a factor of two. The highest chlorine concentrations occur at the same sta- tions where excessive sodium was encountered, suggesting a com- mon source and perhaps a common compound containing both sodium and chlorine. Since there is no urban ULN guideline for chlorine, only the rural guideline of 0.15 % can be used in any comparison. Such a comparison reveals regular exceedances of this concentration. However, such exceedances also occur at control Station 15. Such an observation, which has been made not only at sta- tions around this industrial complex, but also in surveys near other sources, suggests that the ULN guideline for chlorine is not appropriate for silver maple foliage in this geographical area. Consequently, while chlorine does appear to originate from this industrial complex, the significance of the resulting contamination cannot be evaluated. 3.1.5 Long Term Concentration Trends The 1987 report, in addition to examining 1987 data, looked at long term trends in foliage chemistry. There were six sta- tions that had been sampled since 1975 and the foliage analyzed for fluoride, sodium and chlorine. Sampling occurred five times each summer. The means of the six stations over the five sam- pling dates were used in the trend analysis. Although these six stations were sampled in 1988 and 1989, they were only sampled two times each year. Consequently, a full trend analysis could not be continued. However, to permit at least a partial evaluation of the trends. Figures 6, 7, 8 and 9 have been prepared. These figures plot the monthly means of the six stations (1, 16, 18, 29, 30 and 31) when data are available. Figures 6 and 7 represent these six station means for each sampling date since 1975 for fluoride in unwashed and washed foliage. When the May and June, 1988 histograms are compared to the comparable months since 1975, very little, if any, change in foliar contamination is apparent. However, the July and August, 1989 concentrations appear noticeably lower than in those months in most years back to 1975. Figure 8 is an identical representation for sodium in unwashed foliage. Here the May and June, 1988 concentrations appear to be comparable to those since 1985, but generally lower than those prior to 1985. The August 1989 concentration is also similar to those since 1985; however, the July, 1989 concentration is the lowest monthly multi-station mean encoun- tered in the history of Phytotoxicology surveillance around this industrial complex. Because of the limited data base further analysis and interpretation of trends cannot be undertaken. Caution should also be exercised in relating these findings to changes in industrial emissions, as other environmental or climatic fac- tors may be contributing to these observations. It should be noted that in 1991, the complete nine-station, five-sampling date silver maple survey has been re-established and will per- mit additional trend analyses in the future. Figure 9, representing the identical representation of chlorine in unwashed foliage has been included in this report for information only. Trend analysis will not be attempted for reasons outlined in Section 3.1.4. 3.1.6 Foliar Injury Observations During previous silver maple surveys, the foliage on the sampled branches has been examined for indications of injury that could be ascribed to industrial emission impacts. Such examinations were conducted in 1987 and discussed in the 1987 report. This discussion revealed the difficulties with ascrib- ing injury symptoms on this foliage to a specific contaminant. Consequently, in 1988 and 1989 formal notation of fluoride-like or sodium-like injury symptoms was not performed during the collection surveys. 3.2 Complaint Investigations Each year the Phytotoxicology Section is requested to inves- tigate allegations of injury to vegetation on residential prop- erties, primarily on Texas Road, north of the complex. In the majority of these investigations, the injury is inconsistent with the symptoms that would be observed if one of the indus- trial contaminants was the primary causal agent. Such injuries are ascribed to diseases, insects and physiological stress. However, on occasion, symptoms on vegetation are indicative of some influence by either the GCCL or ACCI operation. In 1988, there were three cases where calcium dust from the GCCL lime kiln operation was noted to have impinged on and coated the boles of fruit and ornamental trees on residential properties. Such coating is not necessarily injurious to the tree, but does have a negative aesthetic effect. In 1989, there was one case of trace injury to tree foliage that was symptomatic of fluoride and was so ascribed. In 1990, there was one case of injury to ornamental trees that was attributed, in part, to sodium and fluoride contamination. It must be emphasized that investigations of alleged injury to vegetation on private properties are only conducted on the request of the property owner. 3 . 3 Cottonwood Survey In 1989, a new vegetation survey design was developed to improve the resolution of the locations of the sources of con- taminants emitted by the two industries and to evaluate the rel- ative impacts over distance. To meet these objectives, the stations required a common tree -species that was available at sites very close to the sources as well as at various distances along transect lines. A reconnaissance of the area revealed that the only suitable tree species was eastern cottonwood (Populus deltoides) . Figure 10 displays the distribution of these new sampling stations. Note that there are three series of station designa- tions, identified with the alphabetic characters A, B and C. Stations Al to A6 are accessible via a trail running parallel to the northern boundary of the industrial complex. It should be noted that some of these stations, and possibly Station A8, may be located on lands owned by either ACCI or GCCL. If such is the case, then the stations are within a few metres, at most, from land owned by other parties. This point is made so that in the forthcoming evaluation of contamination of foliage at a station occurring on ACCI or GCCL property, it can be considered compa- rable to a station which might have been immediately beyond com- pany property. All remaining stations are on residential properties. Sta- tion A7 is in the front yard of a Texas Road residence. Stations Bl to B4 are in the back yards of Second Concession residences. Stations CI and C2 are located on residential properties in the town of Amherstburg. Station C3, not shown in Figure 10, is a control station approximately six kilometres south of the indus- trial complex. The method of sampling of foliage was identical to that used in the silver maple survey. Triplicate samples of foliage were taken from the side of the tree facing the industrial complex. Sampling occurred on July 27, 1989 and August 16, 1990. Samples were processed and analyzed for fluoride, sodium, chlorine and calcium on an unwashed basis. There was no laboratory washing of foliage. The results of the individual sample analyses, along with arithmetic means and standard deviations are contained in Appendix 2 . Means of triplicate samples for each station are represented in the paired Figures 11a and lib, 12a and 12b and 13a and 13b for fluoride, sodium and chlorine, respectively. Calcium data are not presented or discussed for reasons given for the silver maple data. Note that the "a" figures are 1989 data and the "b" figures are 1990 data. To enhance the data interpretation, prevailing wind records from Windsor airport were analyzed. This is the nearest meteoro- logical station recording wind directions and it is probably reasonably representative of Amherstburg winds. Hourly prevailing winds for up to 28 days prior to the sampling dates were summed for each of 16 compass points, plus calm conditions. Prevailing wind patterns for 7, 14 and 28 day periods prior to sampling were examined. Figures 14a and 14b represent the 14 day winds in 1989 and 1990, respectively. The 7 and 28 day winds showed virtually identical patterns and are, therefore, not presented. 3.3.1 Fluoride in Cottonwood Foliage Figures 11a and lib represent concentrations of fluoride in Cottonwood foliage. The y-axes scales in these figures are 10 matched to facilitate comparisons between years. The most domi- nant feature of these figures is the difference in maximum con- centrations between years; 51 ug/g at Station A6 in 1989 and 137 ug/g at Station 5 in 1990. The second highest concentrations in each year also occurred at these two sta- tions. Also worth noting are the relatively high concentrations encountered at Station CI in both years. With the exception of the three stations mentioned above, all other stations had concentrations only marginally above or below the rural ULN guideline of 15 ug/g. This illustrates a limited impact zone. However, it must be emphasized that these results cannot be compared with those from previous years in which silver maple was sampled. The differences in the morphol- ogy and physiology between these species would result in dif- ferent foliar concentrations under similar air concentrations of fluoride. The map of the station locations. Figure 10, indicates the relative position of the suspected source of fluoride, the hydrofluoric acid plant operated by ACCI . The initial conclu- sion would be that given prevailing southerly to southwesterly winds, the source of fluoride is the HF plant. However, by examining the wind data for the 14 day periods before sampling, a more detailed analysis is possible. Figures 14a and 14b reveal real differences in wind conditions in 1989 and 1990. The 1990 wind frequencies are more typical of the area, ie. S to SW. However, in 1989, there was a high frequency of winds from the NE as well as from all other directions. Such NE winds may account for the elevated fluoride concentration at Station CI in 1989. Note that this concentration is similar in magni- tude to those at Stations A5 and A6 . In 1990, when typical S to SW conditions returned, the highest concentration was at Station A5, north of the indus- trial complex. However, a closer examination of the position of Station A5 shows that it is NNW of the HF plant. It would require SSE winds to impact this station if the HF plant was the sole source. SSE winds were infrequent. These observations, which allude to a source of fluoride other than, or in addition 11 to the HF plant, must be considered in light of the uncertainty in applying Windsor wind data to Amherstburg. However, addi- tional support is provided in the relatively low concentrations at Station A6 in 1990. This station is NE of the HF plant and would be impacted by emissions from the plant under the gener- ally prevailing SW winds. While these observations are subject to some degree of uncertainty, there remains a strong suggestion of a source of airborne fluoride to the west of the HF plant and east of the chlorof luorocarbon plant. An investigation of possible sources in this area by Ministry abatement staff and ACCI staff is war- ranted. 3.3.2 Sodium in Cottonwood Foliage Sodium concentrations are represented in Figures 12a and 12b for 1989 and 1990, respectively. These figures indicate elevated concentrations at Stations Al through A5, peaking at A6 . Station Bl also has elevated concentrations and will be discussed later. -In 1990, there was a trend of increasing concentration pro- ceeding from west to east in these six stations. This trend was especially distinct in Stations A4 through A6 . Upon examining the wind data in Figure 14b, one can conclude that the sodium ' carbonate plant operated by GCCL is the source of the sodium contamination . In 1989, there is much less of a concentration trend through these stations. Station A6 stands out as having a dis- tinctively higher concentration than any other station. Also lacking is any evidence of notably elevated sodium at Stations CI or C2 as compared to 1990, despite the NE winds of 1989. This later observation contrasts with what was seen for fluo- ride in 1989 when winds blew more frequently from the NE . It may be argued that the sodium emissions, being particulate in nature, are being removed by impingement on other vegetation located between these sites and the emission source. 12 The high concentration at Station A6 in 1989 suggests the possibility of incidental release (s) of sodium compounds from the GCCL operation. A similar conclusion was drawn in the 1987 report based on 1987 silver maple data. Station Bl exhibits unexpectedly high sodium concentrations in both years. Station A7 , which is in a line with the sodium carbonate plant and Station Bl, has low concentrations. The concentrations in 1989 and 1990 are of similar magnitude despite differences in wind patterns. There are strong indica- tions of a sodium source other than the industrial complex. Such a source becomes identifiable when the characteristics of Station Bl site are examined. Station Bl is located at the extremie west of a residential property on the west side of the Second Concession Road. A railway line is a few metres away. The Station Bl tree is at an elevation lower than the railway bed. This rail line is used by hopper cars transporting sodium carbonate. Spillage from the hoppers is very common. Piles of sodium carbonate are situated throughout on the rail beds. Rain dissolving this material could wash it into the rooting zone of the tree at Station Bl . The transport of sodium carbonate in not under the control of GCCL; rather, it is the responsibility of a railway company. Apparently, it is the practice of the railway to keep the hop- per doors of "empty" cars open. Shunting of the cars causes residual sodium carbonate to discharge onto the rail bed. While the Ministry' s Windsor District Office has expressed concern about this problem to the railway, there have been no amend- ments made to the transportation practices. It should be noted that railway operations are under federal jurisdiction. The effect of these transportation practices is to distrib- ute a contaminant to areas which would not otherwise be signif- icantly impacted by atmospheric deposition. To this point, there has not been any discussion of injury to the Cottonwood sample trees. When this survey was designed, it was recognized that this species was not particularly sensi- tive to the chemicals emitted by the two companies. In fact, with one exception, injury was not observed on the sampled 13 trees. During the 1989 sampling, foliage of the tree at Station A6 was distinguished with light to moderate marginal necrosis of approximately 10% of the leaves. This observation was recorded. The chemical data for this station indicate an excep- tionally high concentration of sodium (8000 ug/g) . As the fluo- ride concentration was not similarly excessive (51 ug/g) and well below the range where phytotoxicity would result for this relatively fluoride-tolerant species, the injury can be attrib- uted to sodium contamination. As was mentioned previously, some of the stations north of the industrial complex were situated on ACCI or GCCL property. Station A6, according to maps in the possession of the Phyto- toxicology Section is located off either company's property and only a few metres from an agricultural field. 3.3.3 Chlorine in Cottonwood Foliage Chlorine concentrations are displayed in Figures 13a and 13b. While elevated concentrations are definitely apparent at Stations A4 and A5 each year and occasionally coincide with incr-eases in sodium, the correlation is not strong. Also, the background concentrations are very variable and in some cases, approach the chlorine concentrations found at the sodium impacted stations. Foliar chemical analysis appears to be an inadequate method of detecting and ascribing chronic level chlorine contamination impacts from atmospheric sources. 4 Fluoride Candle Monitoring Since 1975, the Southwest Region has maintained a network of lime candles in the vicinity of the complex. These candles con- sist of filter paper soaked in a suspension of calcium oxide and wrapped onto a glass cylinder. This candle is positioned in the field for a one month period. Fluoride compounds in the air react with the calcium oxide and are retained on the paper until labo- ratory analysis. 14 The candles do not provide direct measurements of gaseous or particulate fluoride compounds in the air. Data are expressed as fluoridation rates which reflect the amount of fluoride which has reacted with a unit surface of the candle over a fixed period of time. The Ambient Air Quality Criteria in Regulation 296 of the Environmental Protection Act for fluoridation rate are 40 ug F/lOO cmVSO days for the period April 15 to October 15 and 80 ug F/lOO cmVSO days for the period October 16 to April 14. More recently the Ministry of the Environment amended the growing sea- son definition to recognize differences in northern and southern Ontario. For the Amherstburg area, the growing season now applies to the period from April 1 to September 30 . Six fluoridation stations in the vicinity of the complex were active in 1990. Four of these were located within the area of the silver maple sample stations, but only three have been active since 1975. Fluoridation rate data from these three sta- tions are used in this report to compare trends in these measure- ments with trends encountered in the fluoride concentrations in silver maple foliage. Fluoridation rates from all six, currently active, sations are tabulated in Appendix 3. This tabulation is restricted to the April through September growing period exposures. These data were retrieved from the Air Quality Information System (AQUIS) data- base . This period encompasses the period during which silver maple samples were collected. Arithmetic means for the six exposure months and the three stations were calculated. Figure 15 repre- sents these mean fluoridation rates from 1975 to 1990. These cal- culations parallel those used in calculating mean foliar fluoride concentrations in the 1987 report where six station by five collection date means were generated. Note that there were no fluoridation rate data for 1982, 1983 and 1984 in AQUIS. The 1987 report noted that there was no discernable trend toward lower concentrations of fluoride in silver maple foliage during the period 1976 to 1987. Section 3.1.5 in this report notes the lack of lower concentrations in 1988, but reports some indication of lower foliar concentrations in 1989. 15 Figure 15 partially supports the steady-state condition encountered in the silver maple foliage. This figure indicates that from the period 1979 to 1989, fluoridation rate means have been fairly constant. In fact, the mean rate of 1976 is also similar. The mean fluoridation rates of 1977 and 1978, however, do appear to be higher. Such elevations were not encountered in the foliage means in those years. Also, the apparent decrease in silver maple foliage fluoride in 1989 as compared to 1988, discussed in Section 3.1.1, is not reflected in the fluoridation rates for these two years. Unfortu- nately, the relatively low fluoridation rate mean of 1990 cannot be compared to silver maple concentrations, as such vegetation samples were not collected. This exercise demonstrates that, while the two monitoring methods - tree foliage chemistry and lime candles - are comple- mentary in assessing long term trends, they cannot be used to make direct comparisons with limited numbers of observations. This is not unexpected, given the numerous factors that affect plant uptake, accumulation and loss of fluoride which would not similarly affect a physical (static) receptor located in a rain protected shelter. It should be noted that, as with fluoride in vegetation, where the Upper Limit of Normal guidelines have been and continue to be exceeded, the Ambient Air Quality Criterion for fluorida- tion rate has likewise been regularly exceeded. Cases of excee- dance of the 40 ug F/lOO cmVsO day criterion have been highlighted in bold text and frequency of exceedances summarized in Appendix 3 . 5 Suspended Particulate Monitoring The AQUIS database also contains data on suspended particu- late concentrations as monitored at one of the lime candle sites, site 12053, between 1981 and 1990. Suspended particulates are monitored by drawing ambient air through, and capturing the par- ticulates on, a filter. Such Hi-Vol samplers are operated for 24 hour periods on a six day cycle. The Ambient Air Quality Criterion for suspended particulates is 120 ug/mV24 hours. 16 For the period 1981 to 1990, there are 502 daily suspended particulate concentration data in the AQUIS. On twelve occasions the criterion was exceeded. Eleven of these occurred in 1981 through 1985. Since emissions by GCCL are likely to be particu- late in nature, it would have been useful to compare air particu- late concentrations with foliar chemistry. However, suspended particulate concentrations would include all particles in the air, not just those emitted by GCCL. Furthermore, the chemical composition of the particles is not determined, and the geo- graphic position and intermittent operation of this single moni- tor is not optimal for tracking trends in GCCL emissions. Early in 1991, two addition sites for particulate monitoring were established. These sites are optimized for monitoring GCCL emissions . 6 Summaxy and Conclusions Two chemical production facilities occupy a common indus- trial complex in the vicinity of Amherstburg. Allied Chemicals Canada Incorporated (ACCI) manufactures hydrofluoric acid and chlorof luorocarbons . General Chemical Canada Limited (GCCL) man- ufactures calcium chloride and sodium carbonate. Emissions from these industries include fluoride compounds in the case of ACCI; and sodium compounds in the case of GCCL. GCCL can also release calcium compounds. Compounds containing the element chlorine can potentially be released by either company, or by a third, unre- lated, company in the vicinity. Emissions of fluoride and sodium can result in contamination of vegetation in the area of the complex, and result in injury to foliar tissue. In 1988, 1989 and 1990, the Phytotoxicology Section con- ducted two types of vegetation surveys in the vicinity of the industrial complex. These surveys investigated the degree of foliar contamination by emissions from these operations. Com- plaints from neighbouring residents alleging vegetation injury caused by emissions were also investigated as received. 17 In 1988 and 1989, silver maple foliage was collected at nine established stations. However, these collections occured two times in each of the two years. A continuation of the analyses of trends in foliar contaminant concentrations, which was initiated in the 1987 report could not be continued since previous collec- tions were conducted five times each year. In 1989 and 1990, a new survey design was employed to iden- tify the sources of the contaminant releases and the geographic extent of their impacts. The survey consisted of transect lines of Cottonwood trees from which foliage was sampled and analyzed. The data were interpreted with the aid of prevailing wind infor- mation for the period preceding the sampling. 6.1 Allied Chemicals Canada Incorporated Analysis of silver maple foliage for fluoride revealed ele- vated concentrations. These concentrations frequently exceeded the Phytotoxicology Upper Limit of Normal Guidelines. Despite the limitations imposed on the continuation of any trend analy- sis by the reduced sampling frequency, concentrations encoun- tered in 1988 were similar to those encountered in other recent survey years. However, the 1989 samples had notably lower concentrations of fluoride. In 1989 and 1990, the new cottonwood surveys revealed ele- vated concentrations of fluoride in cottonwood foliage at sta- tions north of the general area of fluoride production or use. However, a more detailed examination of the contamination patterns with the aid of wind data, suggests the possibility of a source or sources of fluorides in addition to the hydrofluoric acid or chlorof luorocarbon facilities. In 1989, a higher fre- quency of NE winds resulted in more notable contamination of stations in the northern part of the town of Amherstburg. Neither survey design included examination for, or confirma- tion of injury induced by fluoride. However, complaints from residents were examined, and in two cases, it was concluded that fluoride contributed to injury of the vegetation. In this report, data generated by passive fluoride monitors (lime candles) are examined and trends compared to trends in silver maple fluoride concentrations. There is reasonable agree- ment with respect to a lack of notable reductions in the degree of air borne fluoride contamination in the vicinity of ACCI over the past 10 or more years On the basis of these findings, additional Ministry of the Environment investigations of fluoride emission sources and abatement possibilities are warranted to reduce the degree and extent of contamination and reduce or eliminate the potential for injury to vegetation. 6.2 General Chemical Canada Limited Analysis of silver maple foliage for sodium revealed ele- vated concentrations. These concentrations frequently exceeded the Phytotoxicology Upper Limit of Normal Guidelines. Despite the limitations imposed on the continuation of any trend analy- sis by the reduced sampling frequency, concentrations encoun- tered in 1988 were similar to those encountered in other recent survey years. However, the 1989 samples had notably lower concentrations of sodium. In the Cottonwood surveys, sodium concentrations in cotton- wood foliage were highly elevated north of the plant. There was evidence of a trend of increasing concentrations from west to east along the transect line which was parallel to the northern boundary of the industrial complex. An exceptionally high con- centration at one station was detected in 1989. Injury to the Cottonwood foliage at this station was attributed to this high sodium concentration. Sodium was also ruled as contributing to foliar injury, along with fluoride, in one complaint investigation. This survey also revealed a problem with the transport of sodium carbonate. Spillage of this material from railway hopper cars is constantly observed along the railway bed near the com- plex, and contributes to contamination of vegetation, through 19 root uptake, well away from the manufacturing site. It is acknowledged that this material is not under the control of GCCL when spilled. While not causing direct injury to foliage, or notably ele- vating the concentations in the foliage, calcium dust emissions are having deleterious aesthetic effects on tree boles. On the basis of these findings, additional Ministry of the Environment investigations of sodium emission sources and abate- ment possibilities are warranted to reduce the degree and extent of contamination and reduce or eliminate the potential for injury to vegetation. Similar interventions with respect to cal- cium dust emissions would result in reduced negative aesthetic effects . 20 7 Figures 21 Q. < CC LU > _J CO Q III I CO < 0) > 00 > 05 z ^ D-D lVl'''f^'■'''■''''''^'^'|'''l^■''i'■'lV•.M.'|■.|•M'.'.'|1^l^.^M■.lli^.l'l'l^l^l^ R$\ Q LU I i2 ^^ z 2 <>- CELLI I- > 1X1=5 O CO LilO o< D . ,I>^ ];<;<;< _J CO Q LLI X W 0) < 00 z '^ — CO ^§ 20 O kxxvvyx^vyyyyy F [XXA.K.XXX><.X.XXX,..x..,1 k^^M^^iiii o o o o C\J r- (6/6n) NOIiVHiN30NO0 ^JfliaOS a. < tr LU > _j CO Q UJ X CO < 05 > 00 12 3-D ?§ < LU DO l-CC ZD ^!; §8 _J I o '5' o Q. ,RYy^ ivvvyyyyxyyyyyxx T^V/V/ ryyyyyyxyyyyv-^vvvx ^'^-«Msei I^XXXXXX ■ - < ■• ■■ WW IS / ■ ;_.; CD < (7o) NOIiVaiNaONOO 3NiaO1H0 LU _l Q. < ca LU > CO Q LU X CO < d2^ ~ r^ CO 0) Z '- 0> i§ zco LU _1 oo zo 00 i en O D ty!VAW;>y!>y;w^ 2 >■' "^ '^ '^ < / ;< ;< y- ISWWWW -^^ 'i y / y / / / / / / / ^ 05 < -LU >- ® LU > ?co KVV^-" |,^'-,\^,r^,,^,,^,^„^,,^,A,A,,^,,^,,| ui o o in o CvJ C\J (6/6n) NOIiVbiNBONOO 3aiH0niJ a. < LU w Q LU X w ^^»y^ - o o o o o o o o o o m o in o CVJ CVJ ■^ ■^ (5/6n) NOIiVyiNaONOO i^jfiiaos Ol -I Q. < CE LU > CO Q LU I (0 < 22 D^ fs. (OO) zco UJ_I oo zo So o _1 I o O ^^uxw.w.w.v,v/,VAWj 2 c?:?^ t>A^y\/N/ tJ>.W.W..AW...-.V.', »_,'/_ ^ \;!:;z tviW^ff I vv V ^ V y y y y y y y y y y \. ^^^^^^^^^^^^^S '' "^ '?.- ^.- -'\ '^- "^^ ^/ ^\ ■'\ ■' \ ■"'. • '■ ■^^^^^^^WW ESS ^ ,v ,< .^ ,X ,.v V V ;,■ V V V V V V -r ■ i,y,;,y^.y.;.>^»;.;.>?,>-.V;-iV; -^■J) 3) < K/^ -LU lZJ > 2u > i.vv^ yv / ' '^ ■^ ^ ^ -^ l^'^^^'^^^'■',^^■A^^^' '" V '.-> V' ^' V t:— ?- r..-.-vv«-^\VA^>A\. V;--r^--;V:rv-r:v:vr-y--;r;--.'.'."i (o tn •^ CO c\j ^ q 6 6 6 6 o d d (%) NOIlVaiN30NO0 3NiyO1H0 FIGURE 11a; MEAN (Inphcate) FLUORIDE CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - JULY 27. 1989 i ^° A1 A3 AS A7 A9 Al 1 B1 B3 C2 A2 A4 A6 A8 A10 B2 84 CI C3 SAMPLING STATIONS 0 :>AG-88-90\CTWDF F89.CGM FIGURE lib: MEAN (triplicate) FLUORIDE CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - AUGUST 16. 1990 I '° An A3 AS A2 A4 A6 A9 Al A8 AlO SAMPLING STATIONS 81 B3 C2 32 B4 C1 C3 D:\AG-88-90\CTWDFF90.CGM 31 FIGURE 12a: MEAN (triplicate) SODIUM CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - JULY 27. 1989 A9 All A8 A10 SAMPLING STATIONS D :'AG-88-90\CTWDNA89.CGM FIGURE 12b: MEAN (triplicate) SODIUM CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - AUGUST 16, 1990 9 Al 1 AlO SAMPLING STATIONS 0:'AG-88-90\CTWDNA90.CGM 32 FIGURE 13a: MEAN (tnplicale) CHLORINE CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - JULY 27. 1989 S 0.. 9 A1 1 A10 SAMPLING STATIONS D :VAG-88-90\CTWDCL89.CGM FIGURE 13b: MEAN (Inpljcale) CHLORINE CONCENTRATIONS IN COTTONWOOD ACCI/GCCL SURVEY - AUGUST 16, 1990 D:\AG-88-90\CTWOCL90.CGM 33 FIGURE 14a: WIND FREQUENCY - WINDSOR AIRPORT JULY 14 lo JULY 27, 1989 0 :>AG-88-90\WIND 1 -laS.CGM FIGURE 14b: WIND FREQUENCY - WINDSOR AIRPORT AUGUST 3 to AUGUST 16, 1990 3:'AG-88-90\WINOU90,CGM 34 8 Appendix 1: Silver Maple Foliage Concentrations station Sampling Repl F F Na CI Ca F F Na CI Ca Dace •"• uw uw uw uw w uw uw uw uw 1 1. May 30/88 2 3 9 j 130 lie 14 0 170 160 290 290 350 0.14 0.14 0.14 9800 10000 8600 Mean STD 113 13 157 12 310 28 0.14 0.00 3467 618 1 1 1 Jun 28/88 1 2 3 130 no 130 140 150 140 190 200 160 0.12 3.12 0.08 11000 9400 12000 Mean STD 123 9 143 5 183 17 0.11 0.02 10800 1071 1 1 Jul 26/39 1 2 3 66 56 72 91 81 90 180 160 200 0.27 0.29 0.12 9000 9100 9700 Mean STD 65 7 87 4 180 16 0.23 0.08 9267 309 1 1 1 Sep 05/89 1 2 3 89 61 69 120 117 120 150 160 220 0.20 0.35 0.40 9500 6800 7300 Mean STD 73 12 119 1 ■ 177 31 0.32 0.08 7867 1173 12 12 12 May 30/88 1 2 3 19 7 12 7 19 13 140 140 130 0.07 0.06 0.07 3500 9400 6800 Mean STD 13 5 13 5 137 5 0.07 0.00 3233 1078 12 12 12 Jun 28/88 1 2 3 13 14 12 15 12 17 100 99 110 0.39 0.09 0.07 13000 13000 13000 Mean STD 13 1 15 2 103 5 0.08 0.01 13000 0 12 12 12 Jul 26/89 1 2 3 4 5 5 4 6 4 52 52 55 0.33 0.16 0.14 11000 10000 10000 Mean STD 4 0 5 1 53 2 0.21 0.09 10333 471 12 12 12 Sep 05/89 1 2 3 9 7 8 10 10 13 65 57 7.5 0.25 0.23 0.26 12000 11000 15000 Mean STD 8 1 11 2 66 8 0.25 0.01 12667 1700 15 16 16 May 30/88 1 2 3 76 83 71 170 140 170 500 400 500 0.34 0.35 0.32 11000 10000 12000 Mean STD 77 5 160 14 467 47 0.34 0.01 11000 816 16 16 16 Jun 28/88 2 3 85 110 110 200 210 200 ■ 330 400 340 0.33 0.60 0.64 21000 13000 13000 Mean STD 102 12 203 5 357 31 0.52 0.14 15557 3771 16 16 16 Jul 26/89 1 2 3 21 19 21 30 28 33 120 110 120 0.60 0.28 0.45 15000 14000 9400 Mean STD 20 1 30 2 117 5 0.44 0.13 12800 2439 16 16 16 Sep 05/89 1 2 3 49 63 53 147 133 140 590 360 380 0.72 0.55 0.47 12000 11000 9900 Mean STD 55 5 140 443 104 0.58 0.10 10967 358 18 18 18 May 30/88 1 2 3 41 27 34 76 72 60 540 460 350 0.19 0.16 0.19 11000 8800 9000 Mean STD 34 6 69 7 453 74 0.18 0.01 9600 993 18 18 18 Jun 28/88 1 2 3 49 39 45 90 64 110 410 270 370 0.26 0.20 0.31 12000 13000 14000 Mean STD 44 4 88 19 350 59 0.26 0.04 13000 316 18 18 18 Jul 26/89 1 2 3 18 39 28 42 38 34 140 140 62 0.32 0.36 0.25 10000 11000 8800 Mean STD 28 9 38 3 114 37 0.31 0.05 9933 899 18 18 18 Sep 05/89 2 3 21 30 27 57 SI 43 170 210 170 0.41 0.49 0.41 14000 14000 12000 Mean STD 26 4 54 8 183 19 0.44 0.34 13333 943 29 29 29 May 30/88 1 2 3 26 26 28 74 72 75 74 78 82 0.06 0.08 0.06 7800 8800 9000 Mean STD 27 1 74 1 78 3 0.07 0.01 8533 525 29 29 29 Jun 28/88 1 2 3 35 47 40 55 60 68 75 77 73 0.08 0.10 0.11 12000 9100 9400 Mean STD 41 5 61 5 75 2 0.10 0.01 10167 1302 36 station Sampling Repl F F Na CI Ca F F Na CI Ca Date w uw uw UW uw w uw uw uw uw 29 Jul 26/89 15 59 0.19 12000 Mean 10 11 45 0.18 11000 29 2 10 9 35 0.18 11000 STD 1 3 10 0.01 816 29 3 9 10 40 0.16 10000 29 Sep 05/89 1 7 11 60 0.27 14000 Mean 6 11 58 0.25 13667 29 2 7 9 63 0.25 15000 STD 0 1 5 0.02 1247 29 3 6 12 52 0.23 12000 30 May 30/88 1 8 16 100 0.10 12000 Mean 7 19 127 0.11 12667 30 2 7 25 140 0.12 14000 STD 1 4 19 0.01 943 30 3 9 17 140 0.10 12000 30 Jun 28/88 1 10 19 88 0.08 7200 Mean 12 19 106 0.06 8300 30 2 13 19 120 0.05 9200 STD 2 0 13 0.01 829 30 3 14 18 110 0.06 8500 30 Jul 26/89 1 3 3 120 0.07 6700 Mean 4 4 99 0.09 8033 30 2 A 5 80 0.11 6400 STD 1 0 16 0.02 2101 30 3 5 4 96 0.10 11000 30 Sep 05/89 1 11 23 240 0.39 9500 Mean 10 23 227 0.10 8200 30 2 10 24 200 0.07 6900 STD 0 0 19 0.02 1061 30 3 10 23 240 0.12 8200 31 May 30/88 1 46 75 760 0.24 11000 Mean 42 87 787 0.24 11667 31 2 38 100 800 0.29 12000 STD 3 10 19 0.04 471 31 3 43 86 800 0.18 12000 31 Jun 28/88 1 34 50 260 0.15 11000 Mean 34 54 290 0.17 11667 31 2 35 62 290 0.15 13000 STD 1 6 24 0.02 943 31 3 33 50 320 0.20 11000 31 Jul 26/89 1 32 41 230 0.26 10000 Mean 31 35 223 0.30 10667 31 2 19 24 200 0.26 10000 STD 10 8 17 0.06 943 31 3 43 41 240 0.39 12000 31 Sep 05/89 1 18 34 290 0.33 7600 Mean 16 33 443 0.38 12533 31 2 19 36 610 0.52 13000 STD 3 3 131 0.10 3852 31 - 3 12 28 430 0.30 17000 . 32 May 30/88 1 32 85 220 0.08 7200 Mean 20 46 180 0.08 6700 32 2 14 30 180 0.08 7100 STD 8 28 33 0.00 638 32 3 14 22 140 0.07 5800 32 Jun 28/88 1 38 49 93 0.10 5800 Mean 38 58 103 0.09 6333 32 2 45 71 120 0.08 7300 STD 5 9 12 0.01 685 32 3 31 54 ■ 97 0.09 5900 32 Jul 26/89 1 34 34 80 0.13 11000 Mean 27 27 84 0.12 10467 32 2 23 22 84 0.12 8400 STD 5 5 3 0.00 1517 32 3 25 25 87 0.12 12000 32 Sep 05/89 1 10 15 110 0.06 13000 Mean 10 15 120 0.08 10400 32 2 12 16 140 0.08 9100 STD 1 1 14 0.01 1838 32 3 9 14 110 0.10 9100 15 May 30/88 1 7 9 45 0.12 6200 Mean 4 6 44 0.10 5833 15 2 2 3 45 0.11 6100 STD 2 2 2 0.02 450 15 3 4 5 41 0.08 5200 15 Jun 28/88 1 6 7 37 0.16 8200 Mean 6 8 41 0.13 8767 15 2 6 10 42 0.13 3100 STD 0 1 3 0.02 873 15 3 5 7 45 0.11 10000 15 Jul 26/89 1 4 4 13 0.20 9600 Mean 2 3 20 0.24 10533 15 2 2 3 24 0.28 ilOOO STD 1 1 5 0.03 660 15 3 1 2 22 0.24 11000 15 Sep 05/89 1 3 4 48 0.30 11000 Mean 3 4 36 . 0.27 10533 15 2 3 3 33 0.25 8900 STD 0 0 9 0.02 1292 15 3 3 4 26 0.27 12000 37 9 Appendix 2 : Cottonwood Foliage Concentrations station Sampling Repl Date Al Jul 27/89 3.9 690 0.09 21000 Mean 4.1 930 0.11 21667 Al 2 4.2 1000 0.11 24000 STD 0.2 175 0.02 1700 Al 3 4.3 1100 0.13 20000 A2 Jul 27/89 1 6.7 1000 0.15 23000 Mean 8.9 1233 0.21 23000 A2 2 10.0 1300 0.23 32000 STD 1.6 170 0.04 3742 A2 3 10.0 1400 0.24 29000 A3 Jul 27/89 1 4.9 1100 0.22 24000 Mean 4.8 1167 0.24 25667 A3 2 5.1 1300 0.28 26000 STD 0.3 94 0.03 1247 A3 3 4.3 1100 0.23 27000 A4 Jul 27/89 1 13.0 1600 0.53 28000 Mean 16.3 1933 0.44 26667 M 2 21.0 2600 0.48 27000 STD 3.4 471 0.09 1247 A4 3 15.0 1600 0.32 25000 A5 Jul 27/89 1 38.0 2400 0.47 17000 Mean 36.7 2000 0.47 16000 A5 2 40.0 2000 0.49 16000 STD 3.4 327 0.01 816 A5 3 32.0 1600 0.46 15000 AS Jul 27/89 1 51.0 8200 0.26 19000 Mean 51.3 8000 0.26 18000 A6 2 57.0 8200 0.26 19000 STD 4.5 283 0.01 1414 A6 3 46.0 7600 0.25 16000 A7 Jul 27/89 1 9.0 430 0.05 26000 Mean 9.7 520 0.06 29333 A7 2 9.0 390 0.07 27000 STD 0.9 156 0.01 4028 A7 3 11.0 740 0.06 35000 A8 Jul 27/89 1 5.2 510 0.03 25000 Mean 5.1 467 0.03 26000 A8 2 5.1 440 0.03 28000 STD 0.1 31 0.00 1414 A8 3 5.0 450 0.03 25000 A9 Jul 27/89 1 5.1 310 0.08 21000 Mean 5.3 390 0.08 20667 A9 2 5.2 440 0.08 21000 STD 0.2 57 0.00 471 A9 3 5.6 420 0.08 20000 AlO Jul 27/89 1 4.1 170 0.21 28000 Mean 3.6 160 0.20 26667 AlO 2 2.9 130 0.15 23000 STD 0.5 22 0.04 2625 AlO 3 3.8 180 0.25 29000 All Jul 27/89 1 3.4 210 0.05 24000 Mean 3.8 233 0.06 23000 All 2 4.6 260 0.08 25000 STD 0.5 21 0.02 2160 All 3 3.5 230 0.04 20000 Bl Jul 27/89 1 4.4 2000 0.03 20000 Mean 5.0 1367 0.03 20333 Bl 2 5.0 2300 0.03 22000 STD 0.5 419 0.01 1247 Bl 3 5.6 1300 0.04 19000 B2 Jul 27/89 1 5.5 440 0.14 28000 Mean 5.9 410 0.14 28000 B2 2 6.4 350 0.15 29000 STD 0.4 42 0.01 816 82 3 5.8 440 0.14 27000 B3 Jul 27/89 1 6.2 260 0.05 24000 Mean 6.9 313 0.06 23667 B3 2 8.9 400 0.06 24000 STD 1.4 62 0.00 471 B3 3 5.7 280 0.06 23000 BA Jul 27/89 1 3.0 170 0.09 16000 Mean 3.5 203 0.10 15667 B4 2 3.4 210 0.10 15000 STD 0.4 25 0.01 471 B4 3 4.0 230 0.11 15000 CI Jul 27/89 1 34.0 600 0.16 23000 Mean 32.3 543 0.15 22667 cr 2 30.0 480 0.14 23000 STD 1.7 49 0.01 471 Cl 3 33.0 550 0.16 22000 C2 Jul 27/89 1 11.0 220 0.12 19000 Mean 10.7 230 0.12 20333 C2 2 12.0 200 0.12 21000 STD 1.2 29 0.00 943 C2 3 9.1 270 0.12 21000 C3 Jul 27/89 1 5.3 180 0.19 26000 Mean 5.6 227 0.18 24667 C3 2 6.0 230 0.22 27000 STD 0.3 37 0.04 2625 C3 3 5.4 270 0.13 21000 Station Sampling Repl r Na 01 Ca F Na CI Ca :ate ug/g ug/g % ug/g uw uw uw uw Al Ai:g 16/90 6.1 1200 0.10 22000 Mean 6.2 1180 0.11 23333 Al 2 6.4 1400 0.12 24000 STD 0.1 138 0.01 943 Al 3 6.2 940 0.11 24000 A2 Aug 16/90 1 11.0 1500 0.26 36000 .Mean 10.9 1367 0.25 30333 A2 2 9.7 1000 0.18 24000 STD 0.9 262 0.05 4922 A2 3 12.0 1600 0.31 31000 A3 Aug 16/90 1 7.2 1600 0.23 27000 Mean 8.8 1567 0.24 26000 A3 2 13.0 1500 0.24- 27000 ST3 3.0 47 0.01 1414 A3 3 6.3 1600 0.25 24000 A4 Aug 16/90 1 11.0 2700 0.48 21000 Mean 15.3 3000 0.65 28333 A4 2 18.0 3400 0.78 35000 STD 3.1 294 0.13 5735 A4 3 17.0 2900 0.69 29000 A5 Aug 16/90 1 127.7 6400 0.57 19000 Mean 135.6 5033 0.53 17667 A5 2 124.2 4900 0.70 17000 STD 13.7 1066 0.05 943 A5 3 154.8 3800 0.63 17000 A6 Aug 16/90 ]_ 41.0 6800 0.42 21000 Mean 39.0 6033 0.33 18333 A6 2 36.0 5100 0.31 17000 STD 2.2 704 0.07 1886 A6 3 40.0 6200 0.26 17000 A7 Aug 16/90 1 12.0 520 0.09 39000 Mean 13.0 410 0.09 40333 A7 2 14.0 320 0.08 38000 STD 0.8 83 0.01 2625 A7 3 13.0 390 0.10 44000. A8 Aug 16/90 1 7.3 380 0.05 40000 Mean 8.1 560 0.06 38333 A8 2 8.3 620 0.07 34000 STD 0.2 130 0.01 3091 A8 3 8.2 580 0.07 41000 A9 Aug 16/90 1 9.0 390 0.13 22000 Mean 9.4 490 0.13 21333 A9 2 10.0 630 0.12 20000 STD 0.4 102 0.01 943 A9 3 9.3 450 0.13 22000 AlO Aug 16/90 1 9.5 310 0.15 37000 Mean 9.5 297 0.13 34000 AlO 2 9.2 250 0.11 33000 STD 0.2 34 0.02 2160 AlO 3 9.7 330 0.12 32000 ■ All Aug 16/90 1 9.0 530 0.17 26000 .Mean 8.6 573 0.17 26000 All 2 7.9 610 0.16 24000 STD 0.5 33 0.01 1633 All 3 9.0 580 0.19 28000 Bl Aug 16/90 1 7.9 1500 0.05 21000 Mean 6.7 1867 0.05 20667 31 2 6.4 1400 0.05 25000 STD 0.9 591 0.01 3682 Bl 3 5.7 2700 0.04 16000 B2 Aug 16/90 1 9.3 510 0.08 40000 Mean 10.1 553 0.13 39000 B2 2 10.0 510 0.13 36000 STD 0.7 61 0.05 2160 B2 3 11.0 640 0.19 41000 B3 Aug 16/90 1 10.0 650 0.11 39000 Mean 8.3 607 0.09 32667 83 2 8.0 550 0.08 33000 STD 1.2 42 0.01 5312 B3 3 7.0 620 0.08 26000 34 Aug 16/90 1 6.7 500 0.18 23000 Mean 6.4 483 0.16 21000 B4 2 6.6 490 0.12 18000 STD 0.3 17 0.03 2160 B4 3 6.0 460 0.17 22000 CI Aug 16/90 1 27.0 690 0.25 29000 Mean 21.0 530 0.20 28333 CI 2 14.0 350 0.15 30000 STD 5.4 140 0.04 1700 CI 3 22.0 550 0.19 25000 C2 Aug 16/90 i 5.3 270 0.36 17000 Mean 5.9 400 0.38 17000 C2 2 6.4 560 0.38 16000 STD 0.5 120 0.01 816 C2 3 6.1 370 0.39 18000 C3 Aug 16/90 1 7.2 190 0.21 29000 Mean 6.2 143 0.19 25000 C3 2 5.3 120 0.16 20CCO STD 0.8 33 0.02 3742 C3 3 6.1 120 0.21 26000 39 10 Appendix 3: Fluoridation Rates, 1975 to 1990 Station 12053 Ap ril May June July Aug. Sept . Observations Exceedances 1975 1976 1977 1978 1979 1980 1981 57 51 42 38 38 28 6 3 1982 1983 1984 1985 25 11 10 16 10 16 6 0 1986 19 20 20 3 0 1987 34 114 46 21 66 21 6 3 1988 13 17 23 5 32 5 0 1989 19 21 20 19 42 18 6 1 1990 20 12 14 23 15 14 6 0 Station 12074 Ap ril May June July Aug. Sept. Observations Exceedances 1975 36 26 23 17 41 23 6 1 1976 27 19 8 9 37 29 6 0 1977 37 42 22 25 24 25 6 1 1978 19 23 20 21 28 25 6 0 1979 19 27 12 1 24 16 6 0 1980 6 18 18 18 5 5 0 1981 26 25 23 16 20 36 6 0 1982 1983 1984 1985 17 15 12 15 8 14 6 0 1986 14 18 17 3 0 1987 34 35 30 20 23 11 6 0 1988 30 27 18 40 6 23 6 0 1989 19 23 19 21 35 20 6 0 1990 18 10 18 22 23 11 6 0 Station 12087 af ril May June July Aug. Sept . Observations Exceedances 1975 65 106 55 75 125 5 5 1976 85 45 56 4 0 70 88 6 5 1977 130 140 45 63 54 45 6 6 1978 29 43 34 52 916 86 6 4 1979 43 38 35 48 35 5 2 1980 70 62 31 63 38 5 3 1981 41 47 75 55 57 55 6 6 1982 1983 1984 1985 51 37 25 33 25 29 6 1 1986 31 25 40 3 0 1987 24 59 55 42 39 43 6 4 1988 98 42 50 46 12 31 6 4 1989 25 47 62 34 60 26 6 3 1990 49 32 24 27 24 23 6 1 40 Station 12088 April May June July Aug. Sept . Observations Exceedances 1975 161 184 147 193 458 5 5 1976 480 190 190 83 167 238 6 6 1977 901 720 149 169 213 107 6 6 1978 49 105 574 121 346 87 6 6 1979 115 351 335 170 111 5 5 1980 98 203 178 177 68 5 5 1981 259 405 200 86 81 120 6 5 1982 1983 1984 1985 322 222 107 149 80 95 6 6 1986 150 64 262 3 3 1987 80 310 135 99 124 105 6 6 1988 80 104 67 199 44 12 6 6 6 1989 156 185 134 101 132 17 9 5 6 1990 141 72 42 55 38 46 6 5 Station 12092 April May June July Aug. Sept . Observations Exceedances 1975 98 139 36 145 86 5 4 1976 124 84 33 43 98 24 6 4 1977 169 110 55 51 43 5 5 1978 102 86 39 42 60 65 6 5 1979 47 40 64 64 43 5 4 1980 38 79 29 39 22 5 1 1981 68 117 43 27 52 60 6 5 1982 1983 1984 - 1985 110 62 34 86 26 27 6 3 1986 33 80 38 3 1 1987 80 46 60 13 91 19 6 4 1988 110 82 73 41 23 30 6 4 1989 63 64 45 76 128 60 6 6 1990 32 30 18 ICo 29 25 6 1 Station 12095 April May June July Aug. Sept . Observations Exceedances 1975 50 20 22 26 29 5 1 1976 51 34 20 27 36 31 6 1 1977 19 20 29 34 29 22 6 0 1978 27 26 22 26 23 37 6 0 1979 29 29 34 31 20 5 0 1980 18 35 21 35 11 5 0 1981 25 46 11 17 24 28 6 1 1982 1983 1984 1985 17 26 14 17 18 6 0 1986 20 34 20 3 0 1987 24 24 25 22 37 19 6 0 1988 35 64 30 30 10 20 6 1 1989 31 40 28 27 41 45 6 2 1990 22 18 16 26 24 20 6 0 Fluoridation Rates in ug/lOOcm^/30 days Ambient Air Quality Criteria for Fluoridation Rate = 40 ug/lOOcm^/30 days, during the period April 1 to September 30 Exceedances highlighted in bold type 41