GAF

The Oregon Department of Environmental Quality (DEQ) has prepared this fact sheet to answer questions raised by the public concerning the environmental conditions at or near the former View-Master plant, located at 8585 SW Hall Boulevard in Beaverton, and DEQ's selected cleanup action for TCE in groundwater at the site.

DEQ's selected remedy for the site involves groundwater removal from four locations on the site to protect groundwater resources near the site that have not been impacted. The groundwater will be treated in various portions of the site using carbon filtration, air stripping or chemical oxidation treatment methods. The treated groundwater from the air stripping and chemical oxidation treatment systems will be discharged to a wetland area that drains to Fanno Creek through existing storm water drainage systems. Treated groundwater will meet water quality criteria for protection of human health and aquatic organisms. Treated groundwater from the carbon filtration treatment system will be discharged to the sanitary sewer.

· Ventilation system operation and maintenance requirements for the building currently occupied by Powell's Bookstore, and contingency measures if these controls are determined to be ineffective. Air monitoring will be conducted to verify the ventilation system is being properly operated and maintained.

· Interim restrictions on future groundwater use at and adjacent to the site. (This does not involve any restrictions on City of Beaverton backup water supply wells west of the site.)

· Routine surface water monitoring from Fanno Creek and wetland to verify conditions remain protective and are improving; contingencies are included in the event monitoring indicates conditions are not protective.

Prior to DEQ's selection of the final remedy for the site, DEQ issued a 60-day public notice from Nov. 1 through Dec. 31, 2001. DEQ also held a public meeting on Dec. 3, 2001 to provide interested parties with additional information about site conditions and cleanup alternatives considered by DEQ. DEQ's final remedy and response to public comments was issued on February 28, 2002.

Between March and October 2002, DEQ conducted negotiations on a proposed consent decree to implement the final remedy for the site. Prior to entering the proposed settlement, DEQ issued public notice on the proposed decree, which was published in the Secretary of State's Bulletin and The Oregonian and Beaverton Valley Times newspapers on Nov. 1, 2002, in accordance with ORS 465.320. A public hearing was held on Dec. 5, 2002 to receive public comments. The comment period ended on December 6, 2002. A transcript of verbal comments, and written comments received during the hearing and during the public comment period, are included in the DEQ administrative record for the site.

Information on the investigation is available at the Beaverton City Library, 12375 SW Fifth St., Beaverton, and at DEQ's Northwest Region Office, 2020 SW Fourth Ave., Suite 400, Portland. Please call (503) 229-6729 to schedule an appointment to review files.

The final remedy record of decision, which includes figures, the consent decree and DEQ responses to public comments on the decree are available on DEQ's Web site. DEQ's Web address is
http://www.deq.state.or.us/nwr/viewmaster.htm

DEQ's Web site also has general information concerning Oregon Environmental Cleanup regulations, rules, guidance documents, fact sheets, and public notices. DEQ's Web address for this information is
http://www.deq.state.or.us/wmc/cleanup

The original GAF/Mattel facility included three parcels covering 52 acres. The current plant site is limited to a 7-acre portion of Parcel 1. The remaining portions of the 52-acre site were redeveloped for commercial and light industrial uses in the mid-1980s.

In 1996, Mattel Inc. assumed operations of the Tyco Toys Inc. toy manufacturing facility at 8585 SW Hall Boulevard in Beaverton. The Mattel operation was part of what was formerly a manufacturing facility that has been operated over time by several companies. Manufacturing of View-Master viewer and slide projectors began at the site in 1951 by Sawyer's Inc. GAF Corporation (GAF) acquired Sawyer's Inc. in 1966. GAF operated the plant until 1981, when View-Master acquired the pictorial products business of GAF. View-Master merged with Tyco Toys in 1989, and Tyco merged with Mattel in 1996. Mattel ceased manufacturing operations at the plant site in 2000 and vacated the property in May 2001.

Water samples collected from the facility's water supply well in March 1998 contained trichloroethylene (TCE) at levels well above the federal maximum allowable level for TCE in drinking water of 5 parts per billion (ppb). The well was shut down upon discovery of the contamination.

TCE is a non-flammable colorless liquid solvent. It was used at the site from 1952 to 1980 to remove grease from metal parts. Parts degreasing occurred in the paint shop formerly located on Parcel 2 next to the building currently occupied by Powell's Books retail store. Spills of TCE allegedly occurred at the paint shop and other areas of the plant. Drums of degreaser wastes were allegedly dumped on the ground in certain areas on Parcel 3 (a 30-acre parcel of land between the rail spur and Fanno Creek). This was a customary practice by industry at the time, and prior to the enactment of hazardous waste regulations in 1980 that now prohibit such activities.

In November 1998, DEQ issued a consent order to Mattel and GAF, requiring completion of a comprehensive investigation of the original 52-acre facility and adjacent properties. The investigation and interim cleanup actions were completed during the summer of 2001. Significant levels of TCE and associated breakdown products, plus cyanide from film processing, have impacted shallow and deep groundwater resources. Interim cleanup actions were undertaken in July 2000 to control the spread of contamination, while the investigation and final cleanup alternatives were being developed.

· Installation of 130 shallow soil borings to collect soil and groundwater samples; the samples were analyzed for TCE and other chemicals formed by the breakdown of TCE in the environment, and other chemicals historically used at the facility.

Soil testing indicates that levels of contamination in shallow soil (up to 20 feet in depth) do not exceed acceptable risk-based concentrations. While most of the impacted areas are now covered with buildings or asphalt parking, direct contact with the soil by current or future workers during any redevelopment or maintenance work would not pose a significant risk.

Significant levels of TCE are present in limited areas in both shallow and deep groundwater aquifers beneath the site. Areas of TCE contamination in groundwater include:

TCE was found in each of these areas at levels exceeding 10,000 parts per billion. TCE contamination does not extend a significant distance beyond these areas where TCE was released to the environment. Monitoring wells placed in the Greenway park west of Fanno Creek are not contaminated by TCE.

Cyanide, which was used in film processing, was also found in shallow and deep groundwater beneath Parcel 3. Film processing wastewater was disposed of in a land application area and a drainfield in the 1960s.

The use of TCE-contaminated well water was confined to the Hall Boulevard plant. Surrounding buildings use municipal water. Tualatin Valley Water District (TVWD) owns two supply wells located about one mile west of the plant site. Monitoring done during pumping of the wells shows the wells do not draw groundwater from the contaminated areas at the site.

Three wells located east of the site affect groundwater beneath the plant site during pumping. Two of the wells supply irrigation water for the Red Tail Golf Course and the third supplies irrigation water for the Crescent Grove Cemetery. TCE has not been detected in these wells. In the absence of any cleanup, these irrigation wells could become contaminated in the future by drawing groundwater from beneath the site.

Surface water samples were collected from 11 locations within Fanno Creek and a ditch that drains the wetland to Fanno Creek. TCE and breakdown products of TCE (1,2-dichloroethylene or 1,2-DCE, and vinyl chloride) were detected within the wetland ditch and at two locations within Fanno Creek. None of the samples contained these chemicals at levels that exceeded ambient water quality criteria for surface water specified in Oregon regulations.

Cyanide was also found in surface water within the wetlands ditch. The source of the cyanide is from cyanide-contaminated groundwater that discharges to the wetland along the western end of Parcel 3. The film production process at the plant formerly used potassium ferrocyanide, which has low toxicity. Ferrocyanide is broken down by sunlight creating "free" cyanide, which is toxic to fish.

During the fall of 2001, weekly surface water monitoring was done within the wetland to evaluate the levels of free cyanide. The monitoring showed a limited section within the ditch that contained free cyanide exceeding the ambient water quality criteria of 5.2 parts per billion. Cyanide was not detected in Fanno Creek at levels exceeding the ambient water quality criteria.

Children and adult exposure to contaminated surface water was evaluated in April 2000 after TCE was first detected in the wetland ditch in late 1999. A risk assessment was performed to assess whether children that may play in the creek might be at risk through direct contact with the water. To assess the risk, we assumed children used the creek for recreational swimming during the summer months. We assumed that children would inadvertently ingest the water during swimming that contained the maximum detected TCE concentration from the wetland ditch. Actual exposure is likely to be less than what was assumed because the ditch is too narrow and shallow to support recreational swimming. We determined that the level of assumed exposure would not pose an unacceptable risk as defined under Oregon Environmental Cleanup regulations.

Exposure to cyanide within the wetland ditch does not pose a significant risk. The maximum concentration detected in surface water was well below the federal and state drinking water standard of 200 parts per billion.

An ecological risk assessment was prepared that focused on the wetland and Fanno Creek area. The assessment evaluated potential ecological impacts to plants, ground/sediment dwelling organisms (i.e. worms), birds, burrowing mammals (i.e. moles), and fish including threatened and endangered species (i.e. steelhead salmon and coho trout).

Cyanide was the only compound that posed potential impacts to ecological habitat, primarily to fish species. However, significant populations of fish species within the wetlands are not likely due to the presence of a weir where the wetlands ditch drains to Fanno Creek. No evidence of stressed vegetation or obvious impacts to birds and wildlife were observed within the wetlands during ecological surveys and surface water sampling events completed during the investigation.

Samples of indoor air were collected from buildings on View-Master plant site, Powell's Books and Burlington Coat Factory located on Parcel 2, and buildings located on Parcel 3. The sampling was conducted to determine whether TCE vapors had migrated from shallow groundwater beneath buildings into indoor air.

TCE was detected in air samples collected from within the building currently occupied by Powell's Bookstore at levels exceeding DEQ risk-based concentrations. The levels detected, however, were comparable to levels reported in an EPA national study on indoor air quality. Adjustments were made to the ventilation system to control TCE vapor transport into the building. Follow-up sampling indicates the adjustments to the ventilation system effectively reduced the TCE concentrations to levels below DEQ's risk-based concentrations in the ROD.

Interim cleanup measures were implemented in 2000 to control the spread of groundwater contamination in the deep aquifer during the completion of the investigation and development of the final cleanup strategy for the site. The interim treatment measures include pumping from two wells installed at the plant site and one well installed on the western portion of Parcel 3 next to the wetlands.

The water pumped from the wells at the plant site is treated by air-stripping to remove the dissolved TCE to below drinking water standards. The treated water is discharged to the wetland area next to Fanno Creek via the facility's storm water drainage system, under the discharge requirements established by DEQ. TCE levels in the treated groundwater are below the drinking water standard of 5 parts per billion.

Extracted groundwater from the well on the western portion of Parcel 3 is being treated by carbon filtration and discharged to the public sanitary sewer system under a permit issued by Clean Water Services.

Interim remedial action measures have removed and treated more than 100 million gallons of groundwater containing more than 1,500 pounds of TCE since startup in July 2000.

The TCE that is removed from the groundwater by the air stripper is discharged to the atmosphere as a dilute vapor through a 50-foot tall pipe that is attached to a silo located at the southern end of the plant site. Approximately one pound of TCE is discharged to the atmosphere daily over a 24-hour period. The dilute TCE vapor disperses in the atmosphere and is degraded by sunlight.

Prior to DEQ approval of this air emission source, DEQ required GAF to conduct modeling to demonstrate that the levels of TCE vapor discharge would not pose an unacceptable risk to site workers. The modeling results indicated that the TCE concentrations within the atmosphere would not exceed DEQ risk-based concentrations. To verify the modeling results, air samples were collected at the plant site. TCE was not detected during this monitoring.

DEQ will continue to monitor the level of air emissions from the air stripper system at the plant site. If new information indicates the level of air emissions is no longer protective, then actions will be taken to reduce the level of air emissions to acceptable levels.

There are no air emissions of TCE associated with the carbon filtration treatment system on Parcel 3. The TCE in the groundwater is absorbed by the carbon. Monitoring is performed to determine when the carbon needs replacement. The used carbon is sent to a licensed treatment facility where the TCE is removed from the carbon and is recycled.

The chemical oxidation treatment system included under the final remedy will also not have any associated air emissions. This treatment system will destroy TCE and cyanide using ozone and hydrogen peroxide.



	Answers to Questions Concerning Environmental Cleanup of the Former View-Master Site The Oregon Department of Environmental Quality (DEQ) has prepared this fact sheet to answer questions raised by the public concerning the environmental conditions at or near the former View-Master plant, located at 8585 SW Hall Boulevard in Beaverton, and DEQ's selected cleanup action for TCE in groundwater at the site. DEQ's selected remedy for the site involves groundwater removal from four locations on the site to protect groundwater resources near the site that have not been impacted. The groundwater will be treated in various portions of the site using carbon filtration, air stripping or chemical oxidation treatment methods. The treated groundwater from the air stripping and chemical oxidation treatment systems will be discharged to a wetland area that drains to Fanno Creek through existing storm water drainage systems. Treated groundwater will meet water quality criteria for protection of human health and aquatic organisms. Treated groundwater from the carbon filtration treatment system will be discharged to the sanitary sewer. The selected remedy includes the following measures to protect workers at the site and nearby residents, and wildlife within Fanno Creek and adjacent wetlands. · Ventilation system operation and maintenance requirements for the building currently occupied by Powell's Bookstore, and contingency measures if these controls are determined to be ineffective. Air monitoring will be conducted to verify the ventilation system is being properly operated and maintained. · Interim restrictions on future groundwater use at and adjacent to the site. (This does not involve any restrictions on City of Beaverton backup water supply wells west of the site.) · Routine groundwater monitoring to assess progress in cleanup and verify the contaminated areas are shrinking and not expanding. · Routine surface water monitoring from Fanno Creek and wetland to verify conditions remain protective and are improving; contingencies are included in the event monitoring indicates conditions are not protective. · Proper management of soil or shallow groundwater removed from certain disposal areas at the site in the event of excavation during maintenance or redevelopment. The estimated cost of the cleanup is $3 million over a 30-year time frame. Prior to DEQ's selection of the final remedy for the site, DEQ issued a 60-day public notice from Nov. 1 through Dec. 31, 2001. DEQ also held a public meeting on Dec. 3, 2001 to provide interested parties with additional information about site conditions and cleanup alternatives considered by DEQ. DEQ's final remedy and response to public comments was issued on February 28, 2002. Between March and October 2002, DEQ conducted negotiations on a proposed consent decree to implement the final remedy for the site. Prior to entering the proposed settlement, DEQ issued public notice on the proposed decree, which was published in the Secretary of State's Bulletin and The Oregonian and Beaverton Valley Times newspapers on Nov. 1, 2002, in accordance with ORS 465.320. A public hearing was held on Dec. 5, 2002 to receive public comments. The comment period ended on December 6, 2002. A transcript of verbal comments, and written comments received during the hearing and during the public comment period, are included in the DEQ administrative record for the site. For more information Information on the investigation is available at the Beaverton City Library, 12375 SW Fifth St., Beaverton, and at DEQ's Northwest Region Office, 2020 SW Fourth Ave., Suite 400, Portland. Please call (503) 229-6729 to schedule an appointment to review files. The final remedy record of decision, which includes figures, the consent decree and DEQ responses to public comments on the decree are available on DEQ's Web site. DEQ's Web address is http://www.deq.state.or.us/nwr/viewmaster.htm DEQ's Web site also has general information concerning Oregon Environmental Cleanup regulations, rules, guidance documents, fact sheets, and public notices. DEQ's Web address for this information is http://www.deq.state.or.us/wmc/cleanup Background The original GAF/Mattel facility included three parcels covering 52 acres. The current plant site is limited to a 7-acre portion of Parcel 1. The remaining portions of the 52-acre site were redeveloped for commercial and light industrial uses in the mid-1980s. In 1996, Mattel Inc. assumed operations of the Tyco Toys Inc. toy manufacturing facility at 8585 SW Hall Boulevard in Beaverton. The Mattel operation was part of what was formerly a manufacturing facility that has been operated over time by several companies. Manufacturing of View-Master viewer and slide projectors began at the site in 1951 by Sawyer's Inc. GAF Corporation (GAF) acquired Sawyer's Inc. in 1966. GAF operated the plant until 1981, when View-Master acquired the pictorial products business of GAF. View-Master merged with Tyco Toys in 1989, and Tyco merged with Mattel in 1996. Mattel ceased manufacturing operations at the plant site in 2000 and vacated the property in May 2001. Water samples collected from the facility's water supply well in March 1998 contained trichloroethylene (TCE) at levels well above the federal maximum allowable level for TCE in drinking water of 5 parts per billion (ppb). The well was shut down upon discovery of the contamination. TCE is a non-flammable colorless liquid solvent. It was used at the site from 1952 to 1980 to remove grease from metal parts. Parts degreasing occurred in the paint shop formerly located on Parcel 2 next to the building currently occupied by Powell's Books retail store. Spills of TCE allegedly occurred at the paint shop and other areas of the plant. Drums of degreaser wastes were allegedly dumped on the ground in certain areas on Parcel 3 (a 30-acre parcel of land between the rail spur and Fanno Creek). This was a customary practice by industry at the time, and prior to the enactment of hazardous waste regulations in 1980 that now prohibit such activities. In November 1998, DEQ issued a consent order to Mattel and GAF, requiring completion of a comprehensive investigation of the original 52-acre facility and adjacent properties. The investigation and interim cleanup actions were completed during the summer of 2001. Significant levels of TCE and associated breakdown products, plus cyanide from film processing, have impacted shallow and deep groundwater resources. Interim cleanup actions were undertaken in July 2000 to control the spread of contamination, while the investigation and final cleanup alternatives were being developed. Answers to Your Questions What was involved in the investigation? The remedial investigation involved the following activities: · Installation of 130 shallow soil borings to collect soil and groundwater samples; the samples were analyzed for TCE and other chemicals formed by the breakdown of TCE in the environment, and other chemicals historically used at the facility. · Drilling more than 30 shallow and 20 deep wells to monitor groundwater quality over time; · Periodic sampling of surface water in Fanno Creek and the adjacent wetlands from 11 locations; · Periodic testing of indoor air quality in all buildings located where soil and/or shallow groundwater contamination was identified; · A survey to locate wells in the area and test wells to determine whether they have been impacted; · Completion of both a human health and ecological risk assessment to identify what areas needed to be cleaned up and to what levels; and · A feasibility study of potential cleanup alternatives. How extensive is the soil contamination? Soil testing indicates that levels of contamination in shallow soil (up to 20 feet in depth) do not exceed acceptable risk-based concentrations. While most of the impacted areas are now covered with buildings or asphalt parking, direct contact with the soil by current or future workers during any redevelopment or maintenance work would not pose a significant risk. How extensive is the groundwater contamination? Significant levels of TCE are present in limited areas in both shallow and deep groundwater aquifers beneath the site. Areas of TCE contamination in groundwater include: · Parcel 1: the loading dock area at the former View Master facility where a sanitary waste drainfield was located from 1951 to 1962. · Parcel 2: the area around Powell's Books, where degreasing operations historically occurred. · Parcel 3: along the western portion of the parcel that borders the wetlands adjacent to Fanno Creek where solid wastes were reportedly burned; and · Parcel 3: along the eastern border of the parcel next to the rail spur. TCE was found in each of these areas at levels exceeding 10,000 parts per billion. TCE contamination does not extend a significant distance beyond these areas where TCE was released to the environment. Monitoring wells placed in the Greenway park west of Fanno Creek are not contaminated by TCE. Cyanide, which was used in film processing, was also found in shallow and deep groundwater beneath Parcel 3. Film processing wastewater was disposed of in a land application area and a drainfield in the 1960s. Have water supply wells at or near the site been contaminated? The use of TCE-contaminated well water was confined to the Hall Boulevard plant. Surrounding buildings use municipal water. Tualatin Valley Water District (TVWD) owns two supply wells located about one mile west of the plant site. Monitoring done during pumping of the wells shows the wells do not draw groundwater from the contaminated areas at the site. Three wells located east of the site affect groundwater beneath the plant site during pumping. Two of the wells supply irrigation water for the Red Tail Golf Course and the third supplies irrigation water for the Crescent Grove Cemetery. TCE has not been detected in these wells. In the absence of any cleanup, these irrigation wells could become contaminated in the future by drawing groundwater from beneath the site. Is Fanno Creek and wetlands contaminated? Surface water samples were collected from 11 locations within Fanno Creek and a ditch that drains the wetland to Fanno Creek. TCE and breakdown products of TCE (1,2-dichloroethylene or 1,2-DCE, and vinyl chloride) were detected within the wetland ditch and at two locations within Fanno Creek. None of the samples contained these chemicals at levels that exceeded ambient water quality criteria for surface water specified in Oregon regulations. Cyanide was also found in surface water within the wetlands ditch. The source of the cyanide is from cyanide-contaminated groundwater that discharges to the wetland along the western end of Parcel 3. The film production process at the plant formerly used potassium ferrocyanide, which has low toxicity. Ferrocyanide is broken down by sunlight creating "free" cyanide, which is toxic to fish. During the fall of 2001, weekly surface water monitoring was done within the wetland to evaluate the levels of free cyanide. The monitoring showed a limited section within the ditch that contained free cyanide exceeding the ambient water quality criteria of 5.2 parts per billion. Cyanide was not detected in Fanno Creek at levels exceeding the ambient water quality criteria. Are people that use the Greenway at risk from exposure to TCE or cyanide in Fanno Creek or the wetland? Children and adult exposure to contaminated surface water was evaluated in April 2000 after TCE was first detected in the wetland ditch in late 1999. A risk assessment was performed to assess whether children that may play in the creek might be at risk through direct contact with the water. To assess the risk, we assumed children used the creek for recreational swimming during the summer months. We assumed that children would inadvertently ingest the water during swimming that contained the maximum detected TCE concentration from the wetland ditch. Actual exposure is likely to be less than what was assumed because the ditch is too narrow and shallow to support recreational swimming. We determined that the level of assumed exposure would not pose an unacceptable risk as defined under Oregon Environmental Cleanup regulations. Exposure to cyanide within the wetland ditch does not pose a significant risk. The maximum concentration detected in surface water was well below the federal and state drinking water standard of 200 parts per billion. What about wildlife that use Fanno Creek and the wetlands? An ecological risk assessment was prepared that focused on the wetland and Fanno Creek area. The assessment evaluated potential ecological impacts to plants, ground/sediment dwelling organisms (i.e. worms), birds, burrowing mammals (i.e. moles), and fish including threatened and endangered species (i.e. steelhead salmon and coho trout). Cyanide was the only compound that posed potential impacts to ecological habitat, primarily to fish species. However, significant populations of fish species within the wetlands are not likely due to the presence of a weir where the wetlands ditch drains to Fanno Creek. No evidence of stressed vegetation or obvious impacts to birds and wildlife were observed within the wetlands during ecological surveys and surface water sampling events completed during the investigation. Is air quality inside buildings safe? Samples of indoor air were collected from buildings on View-Master plant site, Powell's Books and Burlington Coat Factory located on Parcel 2, and buildings located on Parcel 3. The sampling was conducted to determine whether TCE vapors had migrated from shallow groundwater beneath buildings into indoor air. TCE was detected in air samples collected from within the building currently occupied by Powell's Bookstore at levels exceeding DEQ risk-based concentrations. The levels detected, however, were comparable to levels reported in an EPA national study on indoor air quality. Adjustments were made to the ventilation system to control TCE vapor transport into the building. Follow-up sampling indicates the adjustments to the ventilation system effectively reduced the TCE concentrations to levels below DEQ's risk-based concentrations in the ROD. What's being done to clean up the site? Interim cleanup measures were implemented in 2000 to control the spread of groundwater contamination in the deep aquifer during the completion of the investigation and development of the final cleanup strategy for the site. The interim treatment measures include pumping from two wells installed at the plant site and one well installed on the western portion of Parcel 3 next to the wetlands. The water pumped from the wells at the plant site is treated by air-stripping to remove the dissolved TCE to below drinking water standards. The treated water is discharged to the wetland area next to Fanno Creek via the facility's storm water drainage system, under the discharge requirements established by DEQ. TCE levels in the treated groundwater are below the drinking water standard of 5 parts per billion. Extracted groundwater from the well on the western portion of Parcel 3 is being treated by carbon filtration and discharged to the public sanitary sewer system under a permit issued by Clean Water Services. How much TCE has been recovered and what happens to it? Interim remedial action measures have removed and treated more than 100 million gallons of groundwater containing more than 1,500 pounds of TCE since startup in July 2000. The TCE that is removed from the groundwater by the air stripper is discharged to the atmosphere as a dilute vapor through a 50-foot tall pipe that is attached to a silo located at the southern end of the plant site. Approximately one pound of TCE is discharged to the atmosphere daily over a 24-hour period. The dilute TCE vapor disperses in the atmosphere and is degraded by sunlight. Prior to DEQ approval of this air emission source, DEQ required GAF to conduct modeling to demonstrate that the levels of TCE vapor discharge would not pose an unacceptable risk to site workers. The modeling results indicated that the TCE concentrations within the atmosphere would not exceed DEQ risk-based concentrations. To verify the modeling results, air samples were collected at the plant site. TCE was not detected during this monitoring. DEQ will continue to monitor the level of air emissions from the air stripper system at the plant site. If new information indicates the level of air emissions is no longer protective, then actions will be taken to reduce the level of air emissions to acceptable levels. There are no air emissions of TCE associated with the carbon filtration treatment system on Parcel 3. The TCE in the groundwater is absorbed by the carbon. Monitoring is performed to determine when the carbon needs replacement. The used carbon is sent to a licensed treatment facility where the TCE is removed from the carbon and is recycled. The chemical oxidation treatment system included under the final remedy will also not have any associated air emissions. This treatment system will destroy TCE and cyanide using ozone and hydrogen peroxide.