Air Quality Monitoring for Dioxins, Furans and PCBs in the Swan Hills Area Summer, 1997 (July 7 to August 1)
Alberta Environmental Protection (AEP) is conducting a special air quality monitoring survey in the Swan Hills region of northwestern Alberta. The survey has two components: (1) mobile air quality monitoring throughout the Swan Hills area (including the communities of Kinuso, Fort Assiniboine, Swan Hills, Valleyview, High Prairie, Grouard, Joussard, Slave Lake and Hondo); and (2) stationary monitoring for dioxins, furans and PCBs in the communities of Kinuso, Swan Hills and Fort Assiniboine. The objectives of the survey are to: (1) determine air quality parameter concentrations in the Swan Hills region relative to Alberta’s air quality guidelines and to other locations in the province; and (2) determine concentrations of chemicals that are potentially emitted from the Swan Hills Treatment Centre (SHTC) in local communities. The monitoring survey was initiated in the fall of 1996 and is expected to be complete by the end of February 1998.
The following report is a summary of the results of the dioxin, furan and PCB monitoring activities in the Swan Hills area from July 7 to August 1, 1997. In addition to monitoring at Kinuso, Swan Hills and Fort Assiniboine, a monitoring site was added at the SHTC after the explosion that occurred on July 21. Both kilns at the SHTC were not operating after July 21. A total of 28 dioxin, furan and PCB samples were analyzed at these four locations during the summer monitoring program. Additional monitoring for dioxins, furans and PCBs is scheduled to take place in the winter of 1997/98. Results of mobile monitoring activities in the Swan Hills area are detailed in separate reports.
Major Findings average. The maximum total dioxin concentration recorded at the SHTC (4103 fg/m3) was about 3% + Average toxic equivalent (TEQ) concentrations for of the Ontario 24-hour guideline for total dioxins dioxins and furans monitored in the communities of 0.00015 mg/m3 (150,000 fg/m3). Canada does of Kinuso, Fort Assiniboine and Swan Hills were not have ambient air quality guidelines for total lower than the Alberta and Canadian averages. furans. Average TEQ values in these communities were + 11% of the Alberta average and 19% of the PCB concentrations at Kinuso, Fort Assiniboine Canadian average. and Swan Hills were very low relative to values recorded at the SHTC. The maximum value + 3 Based on samples collected after July 21 (when the recorded in these communities was 0.012 ng/m , two kilns were not operating), TEQ concentrations which is negligible, compared to the Ontario at the SHTC were also lower than the Alberta and guideline of 150 ng/m3. However, total PCB Canadian averages. Average TEQ values at the concentrations exceeded the Ontario 24-hour SHTC were 52% of the Alberta average and 89% guideline at the SHTC in two of the seven samples of the Canadian average. Average and maximum collected after July 21. The maximum PCB TEQ values in samples collected at Kinuso, Fort concentration recorded at the SHTC was Assiniboine and Swan Hills were from 15 to 22% 163 ng/m3, which is about 9% higher than the of those measured at the SHTC. Ontario guideline. Samples were collected at the SHTC after July 21 when the two kilns were not + TEQ concentrations were from 1.1 to 1.8 times operating. higher on July 21 than average TEQ values in samples collected before July 21 in the Monitoring Method communities of Kinuso, Fort Assiniboine and Swan Hills. However, TEQ concentrations Ambient concentrations of dioxins, furans and PCBs dropped off after July 21 in all three communities. were collected at three communities in the Swan Hills TEQ values at these three communities on July 21 area and at the SHTC using PUF (polyurethane foam) were about 20% of the Alberta average. samplers. Air samples were collected as 24-hour to 48- hour concentrations in the communities of Swan Hills, + Average total dioxin and total furan concentrations Kinuso and Fort Assiniboine prior to, during and after at Kinuso, Fort Assiniboine and Swan Hills were the explosion. Sampling at the SHTC was conducted from 2 to 12% of the average values recorded at after the July 21 incident. The C.E. Raymond kiln the SHTC. The average total dioxin concentration (small kiln), Ford Bacon Davis kiln (large kiln) and measured at the SHTC was about Transformer Furnace at the SHTC were not operating after July 21. The 65% of the Alberta average while Alberta the average total furan value at the monitoring schedule is indicated in SHTC was 1.3 times the Alberta Table 1. Air samples were collected using the PUF sampler Kinuso: The community of Kinuso is located about developed by Environment Canada. The sampler 65 km north-northwest of the SHTC. The monitoring consists of a polyurethane foam head attached to a site was on the roof of the Kinuso school. There is light vacuum pump system and works on the same principle local traffic in the vicinity of the monitoring site. as the conventional high-volume sampler. The Highway #2 is located about 3 km south of Kinuso. polyurethane foam is housed inside of a steel cylinder within a PVC cartridge with teflon seals and end caps. Fort Assiniboine: Fort Assiniboine is located The air sample is collected by drawing a known approximately 60 km southeast of the SHTC. The volume of air through the polyurethane foam and a pre- monitoring site was located at the Alberta Forest weighed filter for a specified time period. The Service facility about 3 km northwest of Fort polyurethane foam will capture chemicals such as Assiniboine on Highway #33. The monitoring site was polycyclic aromatic hydrocarbons (PAHs), dioxins, situated 200 m south of the highway. There is light furans and PCBs in the vapour phase. The PUF traffic along Highway #33 and in the Alberta Forest samples were analyzed for dioxin and furan congeners Service facility parking lot. using capillary high-resolution gas chromatography and high-resolution mass spectrometry. Coplanar PCBs SHTC: This site was located on the east fenceline of concentrations were obtained from the PUF samples the plant site near the Central Receiving Facility. There using high-pressure liquid chromatography and GC- is light traffic along the secondary road passing the MSD. Laboratory analysis was conducted by the facility and relatively constant truck traffic on the plant Analysis and Methods Division and the Environment site. Canada Environmental Technology Centre in Ottawa. The combined accuracy of the PUF sampling system Data Analysis and the laboratory analysis method is about ±25%. A total of 28 PUF samples collected in the Swan Hills Monitoring Sites area were analyzed for dioxins, furans and PCBs. The results are presented in terms of toxic equivalents of The monitoring locations in the Swan Hills area are dioxins and furans, total dioxins, total furans and total indicated in Figure 1. The following is a description of PCBs (normalized by compounds within each each monitoring site. homologue group). Table 2 shows average and maximum concentrations for samples collected during Swan Hills: The town of Swan Hills is located 12 km the entire monitoring period, prior to July 21, on southwest of the SHTC. The monitoring site was on July 21 and after July 21. Data from other locations in the roof of the Swan Hills Hospital in the north edge of Alberta and Canada are presented for comparison town. There is residential and hospital traffic in the purposes in Table 3. Dioxin and furan concentrations area. Highway #33 is located less than 1 km west of are presented as femtograms (1 x 10-15 grams) of Swan Hills. dioxins or furans per cubic meter of air (fg/m3). PCB concentrations are presented as nanograms (1 x 10-9 grams) of PCBs per cubic meter of air (ng/m3).
Table 1. Sampling dates for dioxins, furans and PCBs in the Swan Hills area. Sampling Date Kinuso Fort Assiniboine Swan Hills SHTC July 7/8 X X X July 8/9 X July 9/10 X July 17 X X July 21 X X X July 24/25 * X X X X July 25/26 X X X X July 26 to 28 ** X X X July 27 X July 28/29 X July 29/30 X July 30/31 X X X July 31/Aug 1 X Total # of samples 5 9 7 7 * sample was collected for about 36 hours ** sample was collected for about 48 hours Monitoring locations in the Swan Hills area can be viewed at the Special Air Quality Surveys page. http://www.gov.ab.ca/env/air/airqual/special.html Table 2. Average and maximum toxic equivalent, total dioxin, total furan and total PCB concentrations in the Swan Hills area.
Toxic Equivalents (fg/m3) Time Period Kinuso Fort Assiniboine Swan Hills Plant Site Avg. Max. Avg. Max. Avg. Max. Avg. Max. Entire Monitoring Period 11.1 17.2 11.5 20.3 11.3 21.5 53.3 116.6 Before July 21 15.6 15.6 11.5 19.3 13.8 21.5 no data no data On July 21 17.2 17.2 20.3 20.3 20.4 20.4 no data no data After July 21 7.6 10.5 9.4 18.3 7.8 10.3 53.3 116.6
Total Dioxins (fg/m3) Time Period Kinuso Fort Assiniboine Swan Hills Plant Site Avg. Max. Avg. Max. Avg. Max. Avg. Max. Entire Monitoring Period 137.6 298.5 95.2 188.7 79.8 149.4 1144.7 4103.3 Before July 21 90.4 90.4 76.0 158.1 94.2 149.4 no data no data On July 21 298.5 298.5 98.0 98.0 136.4 136.4 no data no data After July 21 99.6 161.2 113.6 188.7 58.4 104.7 1144.7 4103.3
Total Furans (fg/m3) Time Period Kinuso Fort Assiniboine Swan Hills Plant Site Avg. Max. Avg. Max. Avg. Max. Avg. Max. Entire Monitoring Period 51.2 106.9 34.6 128.8 39.9 83.6 1419.8 2513.2 Before July 21 20.8 20.8 45.3 128.8 47.6 83.6 no data no data On July 21 106.9 106.9 25.2 25.2 20.9 20.9 no data no data After July 21 42.8 87.5 26.3 41.5 40.9 60.9 1419.8 2513.2
Total PCBs (ng/m3) Time Period Kinuso Fort Assiniboine Swan Hills Plant Site Avg. Max. Avg. Max. Avg. Max. Avg. Max. Entire Monitoring Period 0.008 0.012 Table 3. Average and maximum toxic equivalent, total dioxin, total furan and total PCB concentrations in the Swan Hills area and other locations in Alberta and Canada. Location (station type) TEQs Total Dioxins Total Furans Total PCBs # of Monitoring Period Avg. Max. Avg. Max. Avg. Max. Avg. Max. Samples Kinuso (rural) 11.1 17.2 137.6 298.5 51.2 106.9 0.008 0.012 5 July 1997 Fort Assiniboine (rural) 11.5 20.3 95.2 188.7 34.6 128.8 Toxic Equivalents (TEQs) of Dioxins and other Alberta locations. Average TEQ concentrations Furans at Kinuso, Fort Assiniboine and Swan Hills were 11.1, 11.5 and 11.3 fg/m3, respectively. These average Dioxins are a family of chemicals consisting of 75 values are about 11 and 19% of the Alberta and distinct compounds. Furans are a family of chemicals Canadian average TEQ values, respectively. The closely related to dioxins consisting of 135 separate average TEQ value measured at the SHTC site 3 compounds. Individual dioxins and furans have (53.3 fg/m ) was close to average values recorded at the Edmonton central (47.8 fg/m3), Fort Saskatchewan varying levels of toxicity. Dioxins and furans 3 3 originate in the atmosphere as by-products of any (55.1 fg/m ) and Fort McMurray (76.4 fg/m ) stations process that involves the incomplete combustion of and lower than the average at the Edmonton east station (199.5 fg/m3). The maximum TEQ value materials containing chlorine and organic matter. 3 Some common industrial sources include pesticide recorded at the SHTC (116.6 fg/m ) was higher than production, wood preservative production, and the maximum values measured at the Edmonton central 3 3 bleaching process used for some pulp and paper mills. (50 fg/m ), Fort Saskatchewan (89 fg/m ) and Fort McMurray (84 fg/m3) stations and lower than the Forest fires are also believed to contribute to dioxins 3 and furans in the environment. Since dioxins and maximum at the Edmonton east station (394 fg/m ). The Canadian average and maximum TEQ furans can be transported over large distances, low 3 concentrations of these chemicals can exist in the concentrations are 60 and 543 fg/m , respectively background atmosphere. The major source of dioxins (based on 220 samples collected by a federal- and furans in the Swan Hills area is the SHTC. Minor provincial program from 1994 to 1997 at urban, rural sources may include forest fires and long-range and industrial locations). transport. TEQ values were generally higher on July 21 than on Toxic equivalents (TEQs) are calculated based on sample days prior to July 21 at Kinuso, Fort international toxicity equivalency factors for 17 dioxin Assiniboine and Swan Hills. Average TEQ and furan isomers and are presented in terms of concentrations were from 10 to 77% higher on July 21 tetrachlorodibenzo-p-dioxin. The international toxic at these three communities. However, average TEQ equivalency factors for each isomer are indicated in values on sample days after July 21 were lower than Table 4. Figure 2 shows TEQs in the Swan Hills area those collected before July 21 at all three for the July monitoring period. communities. Average TEQ concentrations in samples collected after July 21 at Kinuso, Fort Assinboine and Average TEQ values from samples collected in the Swan Hills were from 49 to 82% of the average TEQ Swan Hills area were lower than those recorded at values in samples collected prior to July 21. 200 Kinuso Fort Assiniboine ) 175 3 Swan Hills SHTC 150 Canadian Average Edmonton Central Edmonton East 125 100 75 50 Concentration (fg/m 25 0 July 7/8 July 8/9 July 17 July 21 July 27 July 9/10 July 25/26 July 28/29 July 29/30 July 30/31 July 24/25 * July 31/Aug 1 July 26 to 28 ** * sample was collected for about 36 hours ** sample was collected for about 48 hours Figure 2. Toxic equivalent concentrations of dioxins and furans in the Swan Hills area. Based on data collected after July 21, average TEQ Maximum total dioxin concentrations at the SHTC values at the SHTC were from five to seven times were about 3% of the Ontario ambient guideline of greater than average concentrations in the local 0.00015 mg/m3 (150,000 fg/m3). communities. Average TEQ concentrations were 7.6, 9.4 and 7.8 fg/m3 in Kinuso, Fort Assiniboine and Average concentrations of total dioxins in samples Swan Hills, respectively, compared to 53.3 fg/m3 at collected after July 21 were 1.1 and 1.5 times higher the SHTC. The peak 24-hour TEQ concentration at at the Kinuso and Fort Assiniboine, respectively, than the SHTC (116.6 fg/m3) was also over five times concentrations in samples collected before July 21. greater than the peak TEQ value measured in the three However, average total dioxin values at Swan Hills communities (21.5 fg/m3). were 27% lower in samples collected after July 21. Total dioxin values in all three communities were Total Dioxins from 1.3 to 3.3 times higher on July 21 than average concentrations in samples collected before July 21. Total dioxin concentrations from samples collected in Average total dioxin concentrations in samples the Swan Hills area are indicated in Figure 3. Average collected after July 21 were lower than concentrations total dioxin concentrations in the communities of in samples collected on July 21 at the Kinuso and Kinuso, Fort Assiniboine and Swan Hills were less Swan Hills monitoring locations while average values than 8% of the Alberta average (based on 13 samples at the Fort Assiniboine site were 16% higher after July collected in 1994 and 1995 at the Edmonton central, 21 than on July 21. Edmonton east, Fort Saskatchewan and Fort McMurray stations). The average total dioxin Total dioxin concentrations were from 10 to 20 times concentration at the SHTC (1145 fg/m3) was about higher at the SHTC than at the three communities. 65% of the Alberta average (1753 fg/m3). The Based on samples collected after July 21, average total maximum total dioxin concentration recorded at the dioxin values at the SHTC were 1145 fg/m3 compared SHTC (4103 fg/m3) was also less than the maximum to 100, 114 and 58 fg/m3 at Kinuso, Fort Assiniboine value measured at Alberta stations (6071 fg/m3). and Swan Hills, respectively. 4500 4000 Kinuso Fort Assiniboine ) 3 3500 Swan Hills SHTC 3000 Edmonton Central Edmonton East 2500 2000 1500 1000 Concentration (fg/m 500 0 July 7/8 July 8/9 July 17 July 21 July 27 July 9/10 July 25/26 July 28/29 July 29/30 July 30/31 July 24/25 * July 31/Aug 1 July 26 to 28 ** * sample was collected for about 36 hours ** sample was collected for about 48 hours Figure 3. Total dioxin concentrations in the Swan Hills area. Total Furans concentrations at the SHTC were from 33 to 54 times greater than average values at Kinuso, Fort Total furan concentrations at Kinuso, Fort Assiniboine and Swan Hills. Assiniboine, Swan Hills and the SHTC are indicated in Figure 4. Average total furan concentrations in Total Polychlorinated Biphenyls (PCBs) Kinuso (51 fg/m3), Fort Assiniboine (35 fg/m3) and Swan Hills (40 fg/m3) were less than 5% of the PCBs are a family of chemicals consisting of over 200 Alberta average (1097 fg/m3). Average total furan individual compounds with varying levels of toxicity. concentrations at Alberta stations range from 13 fg/m3 In the past, PCBs were used as coolants and lubricants at the Fort McMurray station to 2987 fg/m3 at the in transformers, capacitors and other electrical Edmonton east monitoring station. The average total equipment because of their insulating and non- furan concentration at the SHTC site (1420 fg/m3) was flammable properties. Because of evidence that PCBs 1.3 times the Alberta average. The maximum 24-hour accumulate in the environment and may cause health total furan concentration at the SHTC was 2513 fg/m3 hazards, PCBs are no longer manufactured in Canada compared to a maximum of 9007 fg/m3 recorded at or the United States. The only source of PCBs in the the Edmonton east monitoring station. Swan Hills area is fugitive emissions or leakages during the destruction of PCBs at the SHTC. Average total furan values were about twice as high in samples collected after July 21 than samples collected Average total PCB concentrations were very low at before July 21 at the Kinuso monitoring site. Total Kinuso, Fort Assiniboine and Swan Hills on all furan values were lower in samples collected at Fort sampling days (Figure 5). The maximum 24-hour Assiniboine and Swan Hills on and after July 21 than concentration recorded at these locations was samples collected before July 21. Total furan 0.012 ng/m3 and was measured on July 7/8 at the concentrations show a five fold increase on July 21 at Kinuso monitoring site. This maximum value is the Kinuso site compared to samples collected before almost negligible compared to the Ontario 24-hour July 21. Winds at Kinuso on July 21 were from the ambient guideline of 150 ng/m3. The average and east-southeast and southeast directions. Kinuso is maximum total PCB concentrations at the SHTC were located 65 km north-northwest of the SHTC. 110.07 and 163.01 ng/m3, respectively. This maximum value is about 9% greater than the Ontario Total furan values were significantly higher at the 24-hour guideline. Total PCB concentrations SHTC monitoring site than in the local communities exceeded the Ontario 24-hour guideline in two of the based on data collected after July 21. Average seven samples collected at the SHTC after July 21. 3500 3000 ) 3 Kinuso 2500 Fort Assiniboine Swan Hills 2000 SHTC 1500 Edmonton East Fort Saskatchewan 1000 Concentration (fg/m 500 0 July 7/8 July 8/9 July 17 July 21 July 27 July 9/10 July 25/26 July 28/29 July 29/30 July 30/31 July 24/25 * July 31/Aug 1 July 26 to 28 ** * sample was collected for about 36 hours ** sample was collected for about 48 hours Figure 4. Total furan concentrations in the Swan Hills area. 180 Kinuso 160 ) 3 Fort Assiniboine 140 Swan Hills 120 SWTC 100 Ontario Guideline 80 60 40 Concentration (ng/m 20 0 July 7/8 July 8/9 July 17 July 21 July 27 July 9/10 July 25/26 July 28/29 July 29/30 July 30/31 July 24/25 * July 31/Aug 1 July 26 to 28 ** * sample was collected for about 36 hours ** sample was collected for about 48 hours Figure 5. Total PCB concentrations in the Swan Hills area. Table 4. International toxicity equivalency factors for dioxin and furan isomers. Dioxin/Furan Isomer International Toxicity Equivalency Factor 2,3,7,8-Tetrachlorodibenzo-p-dioxin 1.0 1,2,3,7,8-Pentachlorodibenzo-p-dioxin 0.5 1,2,3,4,7,8-Hexachlorodibenzo-p-dioxin 0.1 1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin 0.1 1,2,3,7,8,9-Hexachlorodibenzo-p-dioxin 0.1 1,2,3,4,6,7,8-Hepachlorodibenzo-p-dioxin 0.01 1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin 0.001 2,3,7,8-Tetrachlorodibenzofuran 0.1 2,3,4,7,8-Pentachlorodibenzofuran 0.5 1,2,3,7,8-Pentachlorodibenzofuran 0.05 1,2,3,4,7,8-Hexachlorodibenzofuran 0.1 1,2,3,6,7,8-Hexachlorodibenzofuran 0.1 1,2,3,7,8,9-Hexachlorodibenzofuran 0.1 2,3,4,6,7,8-Hexachlorodibenzofuran 0.1 1,2,3,4,6,7,8-Heptachlorodibenzofuran 0.01 1,2,3,4,7,8,9-Heptachlorodibenzofuran 0.01 1,2,3,4,6,7,8,9-Octachlorodibenzofuran 0.001 Source: Summary of point of impingement standards, ambient air quality criteria (AAQCs), and approvals screening levels (ASLs). Standards Development Branch, Ontario Ministry of the Environment and Energy. June 1994. Table 5. Wind direction frequency distribution at monitoring locations in the Swan Hills area. Sampling Date Location N NNE NE ENE E ESE SE SSE S SSW SW WSW W WNW NW NNW July 7/8 Kinuso 0% 8% 0% 0% 8% 0% 42% 17% 0% 4% 4% 8% 0% 0% 4% 4% July 7/8 Fort Assiniboine 0% 0% 0% 0% 9% 0% 14% 5% 0% 0% 0% 5% 9% 32% 9% 18% July 7/8 Swan Hills 0% 0% 0% 0% 0% 0% 0% 4% 0% 17% 17% 26% 9% 13% 13% 0% July 8/9 Fort Assiniboine 0% 0% 3% 0% 0% 0% 20% 7% 7% 0% 3% 7% 0% 10% 23% 20% July 9/10 Fort Assiniboine 0% 3% 3% 0% 16% 6% 3% 3% 3% 3% 6% 6% 3% 6% 28% 9% July 17 Fort Assiniboine 0% 0% 5% 5% 25% 5% 0% 5% 0% 5% 0% 10% 0% 5% 10% 25% July 17 Swan Hills 0% 0% 4% 13% 21% 0% 0% 8% 4% 8% 0% 8% 13% 17% 4% 0% July 21 Kinuso 0% 4% 4% 0% 13% 43% 26% 0% 0% 0% 0% 0% 4% 0% 4% 0% July 21 Fort Assiniboine 0% 0% 8% 0% 8% 8% 42% 8% 0% 0% 0% 0% 0% 13% 13% 0% July 21 Swan Hills 0% 0% 0% 0% 50% 46% 4% 0% 0% 0% 0% 0% 0% 0% 0% 0% July 24/25 Kinuso 0% 0% 3% 0% 3% 6% 9% 6% 12% 3% 21% 6% 15% 15% 3% 0% July 24/25 Fort Assiniboine 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 18% 29% 18% 0% 0% 35% July 24/25 Swan Hills 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 16% 59% 24% 0% 0% July 24/25 SHTC 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 35% 57% 9% 0% July 25/26 Kinuso 0% 0% 4% 0% 4% 8% 8% 8% 4% 12% 12% 0% 12% 24% 4% 0% July 25/26 Fort Assiniboine 0% 0% 0% 0% 9% 0% 0% 0% 5% 0% 27% 41% 0% 5% 5% 9% July 25/26 Swan Hills 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 38% 46% 13% 4% 0% July 25/26 SHTC 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 4% 42% 50% 4% 0% July 26 to 28 Kinuso 0% 7% 17% 4% 11% 17% 7% 4% 2% 4% 7% 4% 4% 4% 0% 7% July 26 to 28 Fort Assiniboine 0% 2% 0% 2% 22% 2% 22% 2% 4% 0% 0% 7% 11% 11% 9% 7% July 26 to 28 Swan Hills 0% 0% 0% 17% 29% 10% 0% 2% 0% 0% 0% 0% 7% 24% 7% 5% July 27 SHTC 0% 0% 8% 4% 33% 0% 0% 0% 0% 13% 0% 0% 0% 0% 38% 4% July 28/29 SHTC 0% 0% 0% 4% 4% 32% 56% 0% 4% 0% 0% 0% 0% 0% 0% 0% July 29/30 SHTC 0% 12% 4% 4% 12% 24% 36% 8% 0% 0% 0% 0% 0% 0% 0% 0% July 30/31 Fort Assiniboine 0% 4% 13% 0% 0% 9% 0% 4% 0% 0% 0% 17% 13% 4% 30% 4% July 30/31 Swan Hills 0% 0% 0% 21% 54% 0% 0% 0% 0% 0% 0% 4% 21% 0% 0% 0% July 30/31 SHTC 0% 0% 0% 4% 19% 4% 0% 0% 0% 0% 0% 4% 0% 69% 0% 0% July 31/Aug. 1 SHTC 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 0% 67% 33% 0%