General Motors/Central Foundry Division - Update
In 1999, the federal Agency for Toxic Substances and Disease Registry (ATSDR) released a Public Health Assessment (PHA) for the General Motors (GM) - Central Foundry Division Massena Plant (ATSDR, 1999). The New York State Department of Health (NYS DOH) prepared the document under a cooperative agreement with ATSDR. The public health assessment, which is an analysis and statement of the public health implications posed by the facility, was based on information current to July 31, 1995 and published with the understanding that an update would be prepared when additional information became available. At that time, the site was identified as a public health hazard due to ongoing exposures, especially exposures to PCB contamination in fish and wildlife. Since 1995, GM, as required by the Records of Decision (RODs) (US EPA, 1990 and 1992) and Record of Decision Amendment (US EPA, 1999), completed several remedial actions. The purpose of this Health Consultation is to provide an update on site activities since 1995 and provide an assessment of exposures based on site conditions as of September 2007. Previous environmental data and public health implications were provided in the 1999 PHA, and are not repeated in this health consultation. A listing of reports providing a comprehensive summary of remedial activities conducted for this site are included in the Reference section of this report.
This public health consultation was distributed for public comment on September 26, 2006. The public comment period ended on October 26, 2006. A summary of the comments and the NYS DOH's responses are included in Appendix C.
Site Description and History
The GM Central Foundry is in the Town of Massena, St. Lawrence County, about eight miles east of the Village of Massena (Appendix A, Figure 1). The GM property is bordered on the north by the St. Lawrence River, on the south by the Raquette River, on the west by County Route 45 and on the east by the Franklin County line and the St. Regis Mohawk Indian (or Akwesasne) Reservation (Appendix A, Figure 2).
The GM plant is an aluminum casting facility built in 1959 to manufacture automobile components, including engines, transmissions and cylinder heads. From 1968 through the late 1970's, GM used hydraulic fluids containing polychlorinated biphenyls (PCBs) in its die casting machines. Operations at the facility generated PCB-containing sludge from oil reclamation. Subsequently, wastewater containing PCB-laden oil was sent to four on-site lagoons where solids were settled before wastewater was discharged into the St. Lawrence River. PCB sludge was periodically removed from the lagoons and wastewater plant for disposal into the North and East Disposal Areas and Industrial Landfill. Some PCB containing waste migrated from the property off-site, to adjacent property and waterways, through wastewater outfalls and storm water runoff. The contamination was discovered in the late 1970s through routine monitoring. This led to listing of the site on the New York State Registry of Hazardous Waste Sites and ultimately on the federal National Priority List (NPL) in 1983. The plant has used a process known as the "lost foam" casting method since the early 1980s. This process, historically, had been the source of air emissions that produced odor complaints by nearby residents. In the mid-1990s, GM installed upgraded air pollution controls to reduce these releases. Emissions have been and continue to be monitored under an air permit issued by the New York State Department of Environmental Conservation (NYS DEC) Division of Air Resources. In May 2007, GM announced plans to close the plant by the end of 2008.
GM initiated a remedial investigation (RI) under CERCLA in 1985, pursuant to an administrative order on consent, to determine the nature and extent of contamination. The RI and subsequent investigations determined that site contaminants included PCBs, phenolic compounds, polycyclic aromatic hydrocarbons, phthalates, and metals. PCBs are considered the primary site contaminant of concern (on- and off-site) because they are the most prevalent contaminant and present potential health-related concerns, which are addressed in the 1999 PHA. The off-site contamination was primarily identified as PCB-containing sediment in portions of the St. Lawrence River and in Turtle Cove. Turtle Cove is an embayment on the St. Lawrence River near the St. Lawrence and Franklin County boundary line, which separates the GM facility from the Akwesasne reservation of the St. Regis Mohawk Tribe (SRMT). In addition, PCBs were identified in the sediment and soils associated with a portion of the Raquette River to the south of the GM facility and Akwesasne reservation, as well as in soil on the Akwesasne Reservation known as the Mohawk Uplands. Based on the information presented in the RI, a feasibility study (FS) presenting remedial alternatives analysis was completed by GM and submitted to the US EPA for review in 1989.
To facilitate remedial activities, the site was split into two operable units. Operable Unit 1 (OU-1) includes all on-and off-site areas except for the on-site Industrial Landfill and East Disposal Area. A proposed remedial action plan for OU-1 was prepared by US EPA in March of 1990 and the ROD was signed in December of 1990. In 1992, the US EPA issued an Explanation of Significant Differences (ESD), allowing for consideration of additional data in re-evaluating the OU-1 remedy treatment requirements and PCB cleanup levels. Additionally, in 1999, the US EPA modified its 1990 ROD for OU-1 to allow off-site disposal rather than on-site treatment of material contaminated with PCBs above 10 milligrams per kilogram (mg/kg) from a specific subset of remedial activities. In 2000, a second ESD for OU-1 was issued, allowing excavated material from the 1.5 million-gallon and 350,000 gallon lagoons to be solidified prior to shipping off-site. There were no changes to the remedial cleanup goals associated with either the ROD modification or ESD. The second operable unit (OU-2) includes the Industrial Landfill and the East Disposal Area. A ROD was issued in March 1992 for Operable Unit 2 (OU-2). The Remedial Action Plan for OU-2 has not yet been finalized. Following issuance of the proposed plan for each operable unit, public meetings were conducted and public comments were addressed in the Responsiveness Summary of each ROD.
Complete summaries of site history and remedial activities are presented in the site Remedial Investigation reports, 1999 PHA, and the Five-Year Review Report (US EPA, 2005). These documents are available for review at the document repositories at the SRMT Environmental Division and USEPA Region 2 offices.
Although the RODs have not been fully implemented, GM has completed considerable remedial work since the 1990s. All remedial activities associated with the RODs for OU-1 and OU-2 are being conducted with daily US EPA oversight. Post-remedial sampling has been and will be conducted to confirm that cleanup objectives are met. As an update to the 1999 PHA, the following is a list of completed and on-going remedial activities from 1995 through 2007.
- 1994-1995: Miscellaneous PCB-contaminated on-site soils were excavated and consolidated into the East Disposal Area;
- 1995: A storm water retention basin was installed to capture surface water from the plant site and East Disposal Area;
- 1995: The St. Lawrence River dredging project was completed. Sediments contaminated with PCBs were removed from the St. Lawrence River and placed in an on-site containment cell. Due to difficulties in dredging around river bottom boulders, a portion of the remedial area with elevated levels of PCBs was capped and armored (larger stones were placed on top of capping material to prevent erosion) to reduce contamination of river fish. GM will continue to inspect and monitor the integrity of the underwater sediment cap. Underwater video surveys are conducted every five years, with the most recent completed in 2006. Any repairs to the armored cap will be made when necessary. The approved plan for monitoring the St. Lawrence River will be incorporated into the Site Inspection, Monitoring, and Maintenance Program.
- 1999: GM received permission from NYS DEC Division of Water to dredge the permitted 10 million-gallon lagoon as part of the routine maintenance program. Dredged materials from the lagoon and from the St. Lawrence River project were solidified and shipped off-site for disposal at a permitted facility. The lagoon is still an active part of the current wastewater treatment process and has the potential to receive wastewater containing residual PCBs (from internal pipes and valves that have previously been cleaned of PCBs);
- 2000: Work began to excavate PCB-contaminated sludge, soils and debris from the 350,000- and 1.5 million-gallon lagoons for disposal. Refer to Item 9 below outlining completion of this remedial action.
- 2000: GM completed a site-wide groundwater well evaluation and abandonment program.
- 2003: The Raquette River remediation project was completed. PCB-contaminated river sediments and associated riverbank soils on the southern portion of the GM property were excavated for disposal. Cleanup goals were achieved and restoration activities were successful.
- 2003: GM removed 5,000 cubic yards of PCB-contaminated soil from the toe of the slope north of the Industrial Landfill, adjacent to Turtle Cove. A groundwater collection system was installed along the southern face of the excavation. Refer to Item 10 below for additional information regarding this remedial action.
- 2004: Remedial work was completed at the 350,000- and 1.5 million-gallon lagoons. Not all of the contaminated soils were removed from the area adjacent to the 350,000 million-gallon lagoon due to soil instability issues. A localized groundwater collection system was installed to monitor, collect and treat groundwater from this location. The 350,000 and 1.5 million gallon lagoons were backfilled to pre-remediation grades with imported clean material, lined and put into service to collect and hold treated process water and storm water.
- 2004: A groundwater collection system transfer line was installed from the collection trench north of the on-site Industrial Landfill (OU-2) to GM's onsite wastewater treatment system.
- 2005: GM completed excavation of contaminated sediment and associated soils from Turtle Cove. The 0.1 mg/kg PCB in sediment cleanup goal was met.
- 2006: Soil sampling was conducted on the Akwesasne reservation, in the Mohawk Uplands east of the GM plant. Refer to Item 15 below outlining completion of this remedial action.
- 2006: Eighteen new monitoring wells were installed for groundwater data assessment and hydrogeologic evaluation.
- 2007: GM submitted a draft Site Inspection, Monitoring, and Maintenance Program for review by US EPA, NYS DEC, and NYS DOH.
- 2007: Offsite remediation of PCB containing soils above the site-specific EPA remedial level is underway in the Mohawk Uplands. Access has not been granted to remediate one of the three properties containing contaminated soils; negotiations with the property owner are ongoing.
The 10-million gallon lagoon and a 500,000-gallon lagoon are a part of the current operational wastewater treatment system. The lagoons are routinely dredged during maintenance and excavated material is transported off-site to a permitted facility. Cleanup requirements for these lagoons will be met when the lagoons are taken out of service.
In accordance with the 1999 ROD modification, stockpiled soil from specific removal actions have been shipped off-site for disposal at a permitted hazardous waste disposal facility. Five sediment and soil stockpiles located west of the Industrial Landfill have not yet been shipped off-site. The sediment and soils originated from various site remedial activities. The stockpiles are engineered containment cells that are lined, bermed and capped.
Areas of concern that have not yet been remediated include Turtle Creek and localized areas on the Mohawk Uplands. These areas requiring additional remediation are all on the Akwesasne Reservation. Additional delineation of these areas was conducted in 2006 where property access was granted and remediation began in 2007. Remediation of the North Disposal Area, East Disposal Area, and Industrial Landfill is ongoing.
Environmental Contamination and Exposure Pathways
PCBs, which were used at the GM facility in the form of hydraulic fluids for die casting machines, are the primary contaminants of concern at the GM site. Below is a discussion of environmental contamination and exposure pathway issues that were not completely addressed in the 1999 PHA. The 1999 PHA contains more detail on previously identified contamination and exposure pathways than is presented below. The following information is an addendum to the 1999 PHA.
PCBs have been detected in some on-site groundwater monitoring wells. The movement of groundwater beneath the site is predominantly northeast toward the St. Lawrence River and the Akwesasne Reservation. A permanent groundwater collection system was installed north of the Industrial Landfill to reduce the movement of contaminated groundwater into the St. Lawrence River. Groundwater monitoring wells were installed in this area and sampled in Fall 2006. An assessment of groundwater quality and hydrogeologic variables is underway following a second groundwater sampling event of site wells, including the 18 newly installed wells, in spring 2007. Exposure to contaminated groundwater is not expected as the water supply for the GM facility is taken from the St. Lawrence River and has been monitored yearly for PCBs. PCBs have not been detected in the raw, untreated water since 2000. The intake water is primarily used as process water; potable water is primarily from bottled water. Groundwater monitoring will continue at the site.
Residual surface soil contamination is present on-site, primarily in the area of the disposal areas and the lagoons. Much of the contaminated soil on-site has been removed and/or covered by the remedial actions. Drainage controls are currently in place to reduce further migration of contaminants in soil. Due to capping of on-site soils and site access restrictions, exposures to on-site contamination are likely to be limited. At this time, an interim soil cap exists for on-site contaminated soils in the East Disposal Area and the Industrial Landfill [OU-2]. A permanent, engineered action has not been applied as future disposal of these soils under a Remedial Action Plan has not yet been finalized for this area. This area is currently fenced to restrict access.
Removal of contaminated sediments and associated riverbank soils has been completed for the St. Lawrence and Raquette Rivers. Where cleanup levels could not be achieved in the St. Lawrence River, the area of residual contamination has been capped. The cap will continue to be inspected and monitored.
Limited exposures to contaminated drinking water may have occurred in the past where low levels of PCBs were detected in one well in one event. Resampling did not detect PCBs. However, all homes have now been connected to a public water supply that is regulated and monitored on yearly for PCBs. Additional information is available in the 1999 PHA and in the Five-Year Review Report (US EPA, 2005).
Subsequent to the 1999 PHA, NYS DOH received and reviewed copies of the monitoring data for the water intake of the SRMT municipal water supply during the dredging of the St. Lawrence River. No PCB contamination was found above the reporting detection limit of 0.05 micrograms per liter (mcg/l), which is well below the US EPA and New York State maximum contaminant level of 0.5 mcg/l for drinking water.
Areas of off-site surface soil contamination were identified beyond the site's eastern property line on the Akwesasne Reservation. In particular, contamination is found in sediments and soils on the Mohawk Uplands and Turtle Creek. The ROD requires removal of soil on the Reservation containing greater than 1.0 mg/kg of PCBs. Potential exposure to PCB-contaminated surface soil on the Reservation may have occurred in the past from unrestricted access to contaminated soils and sediments. Exposure to PCBs in surface soil through incidental contact or ingestion of contaminated soil or by inhalation of contaminated dust particulates by individuals engaging in recreational activities may continue until remediation of the soils occurs. Actions to remove contaminated soils on residential properties on the Akwesasne Reservation began in 2007. One residential parcel has yet to provide access for remedial sampling and soil removal.
Surface Water and Sediment
PCB contamination was detected in the water and sediment of the St. Lawrence River, Turtle Cove, and Turtle Creek. Sediment in the St. Lawrence River near the plant outfall contained up to 5,700 mg/kg of PCBs. The highest level of PCB contamination found in river water was 2.2 mcg/L. In 1995, GM completed its sediment removal effort in the St. Lawrence River. The cleanup goal could not be attained in one section of the river bottom because of difficulties in dredging around river bottom boulders. This area was subsequently capped and armored (larger stones were placed on top of capping material to prevent erosion) to reduce exposure of biota to the PCBs remaining in the river. Dredged sediment was stockpiled and disposed of off-site at a permitted facility in 1999. Sediments in Turtle Cove contained up to 4,100 mg/kg of PCBs, at one sample location, and associated bank soils contained up to 49 mg/kg of PCBs. Remediation of Turtle Cove started in the fall of 2004, with restoration of the remediated area completed in the spring of 2005. The project removed impacted sediments from the cove that had PCB concentrations greater than 0.1 mg/kg and impacted soils in the upland areas that had PCB concentrations greater that 1 mg/kg. Data from the GM Phase I and Phase II RI/FS indicate that PCBs were detected as high as 3,101 mg/kg in Turtle Creek.
Direct contact with and ingestion of PCBs while engaging in recreational use of Turtle Cove and Turtle Creek has been a potential exposure pathway in the past. Direct contact with and incidental ingestion of PCB-contaminated sediments, bank soils, and surface water along Turtle Creek remain potential exposure pathways until remediation is completed.
New York State Fish Monitoring and Advisories
NYS DOH issues advisories on eating sportfish and game because some of these foods contain chemicals at levels that may be harmful to health. The health advisories are: (1) general advice on sportfish taken from waters in New York State; (2) advice on sportfish caught in specific New York State waterbodies; (3) advice for women, infants and children, and (4) advice on eating New York State game. The general advisory for sportfish is to eat no more than one meal (1/2 pound) per week of sportfish from any of the State's fresh waters and some marine waters at the mouth of the Hudson River (NYS DOH, 2007).
NYS DEC provides the fish and wildlife data that NYS DOH uses to derive the advisories. When reviewing fish contaminant data to derive fish advisories, NYS DOH considers the following:
- fish contaminant levels, including fish sampling characteristics (e.g. number and type of samples, species, age, length, percent lipid, sample location, etc.);
- health risks;
- populations at greater potential risk;
- U.S. Food marketplace standards;
- health benefits; and,
- risk communication issues.
Waters adjacent to the GM facility that have advisories include Turtle Cove, Turtle Creek, the entire St. Lawrence River, and the Raquette River (from its mouth on the St. Lawrence River upstream to the first barrier impassable to fish). Due to concerns regarding fish contamination with PCBs (and also Mirex and dioxin), NYS DOH advises women of childbearing age and children under the age of 15 not to eat any fish of any species from the entire St. Lawrence River and the Raquette River (from its mouth on the St. Lawrence upstream to the first barrier impassable by fish); other people are advised to avoid or restrict consumption of certain fish species from these waters. Due to elevated PCB levels, NYS DOH advises no fish, of any variety, should be consumed from Turtle Cove and Turtle Creek. Although the Raquette River and Turtle Creek advisories are not specifically listed, they are tributaries of the St. Lawrence River and NYS DOH advisories apply to listed waters and their tributaries upstream to the first barrier impassable by fish. The St. Lawrence River advisories should not be interpreted as solely restricted to the area around the GM facility in Massena. For more information about the advisories and how they are established, see "Chemicals in Sportfish and Game" (NYS DOH, 2007).
It has been several years since the St. Lawrence River and Turtle Creek Cove advisories have been changed. NYS DOH has not received any site-related fish contamination data from the NYS DEC for fish advisory review since remedial actions were implemented. (The NYS DEC has collected PCB data on whole spottail shiners collected post-remediation. However, these samples are inappropriate for fish advisory evaluation. Samples for fish advisory evaluation should consist of important species consumed by anglers and the should be prepared as DEC standard fillets. Currently, a fish monitoring plan is being developed.)
St. Regis Mohawk Tribe Fish Advisories
Fish and wildlife contamination is of particular interest to the SRMT because these game species have traditionally been an important part of their diet. Consumption of PCB-contaminated fish and wildlife occurred in the past, may be presently occurring and may continue to occur. Consumption of local fish by community members appears to have declined over time, presumably as the result of the advisories that have been issued and other educational efforts over the last decade (ATSDR/NYS DOH, 1995: Fitzgerald et al, 1999).
The SRMT Environment Division issues a general advisory to their community members to eat no more than one meal per week of any fish. The SRMT Environment Division recently issued a specific advisory for smallmouth bass due to elevated levels of PCBs and mercury. This SRMT advisory follows the NYS DOH guidance that women of childbearing age and children should not eat smallmouth bass, and women no longer having children and men to consume a ½ pound or less per week of this fish species and should restrict consumption to one meal per month. NYS DOH and ATSDR have been working with the SRMT Environment Division to promote adherence to these advisories.
Statewide Advisories on Snapping Turtles and Waterfowl
NYS DOH also has statewide advisories regarding consumption of snapping turtles (based on PCB contamination) and wild waterfowl (based on PCB, mirex, chlordane and DDT contamination), as follows:
Snapping turtles retain contaminants in their fat, liver, eggs, and to a lesser extent, muscle. If you choose to consume snapping turtles, you may reduce your exposure by carefully trimming away all fat and discarding the fat, liver, and eggs prior to cooking the meat or preparing soup. Women of childbearing age, infants, and children under the age of 15 should avoid eating snapping turtles or soups made with their meat (NYS DOH, 2007).
Mergansers (a diving duck species) are the most heavily contaminated waterfowl species and should not be eaten. Eat no more than two meals per month of other wild waterfowl: you should skin them and remove all fat before cooking, and discard stuffing after cooking. Wood ducks and Canada geese are less contaminated than other wild waterfowl species and diving ducks are more contaminated than dabbler ducks (NYS DOH, 2007).
PCBs in air were not fully evaluated during the RI. Since PCBs have a low volatility (do not easily evaporate), air emissions were not considered a primary route of exposure. However, fugitive airborne dust from remedial construction activities may pose inhalation concerns. As such, during construction activities, as a part of the community air monitoring plan (CAMP), air is routinely monitored for PCBs.
Historic ambient air monitoring data collected during remedial activities detected levels above the background range for rural continental areas (0.0002 micrograms per cubic meter (mcg/m3) – 0.0015 mcg/m3) (ATSDR, 2000). Air monitoring will continue whenever remedial construction activities occur related to contamination from the GM facility, as required in the ROD.
Monitoring for PCBs in air occurred during the 2002-2003 Raquette River remediation project. A total of 251 air samples from four air monitoring stations near the active work zone were analyzed for PCBs using National Institute for Occupational Safety and Health (NIOSH) Method 5503. No PCBs were detected in any of the 251 air samples above 1 mcg/m3, which is the NIOSH recommended guideline for worker safety. In addition, 38 air samples were collected from two off-site air monitoring stations using a high volume air collection method and analyzed for PCBs using US EPA Method TO-4. The monitoring stations were located near the closest potential off-site residences, east and west of the remediation area. PCBs were detected in three of the 38 air samples. Detected PCBs ranged from 0.0016 mcg/m3 – 0.0035 mcg/m3. PCB background samples that collected from an upwind location prior to the initiation of remedial activities (0.0045 mcg/m3 and 0.0042 mcg/m3). All detected results were below site background levels and US EPA site-specific action levels (Evaluation Level of 0.07 mcg/m3 and the Contingency Level of 0.11 mcg/m3).
Air monitoring for PCBs was conducted throughout the 2004/2005 Turtle Cove remediation project. A total of 254 air samples were collected for analysis, using procedures described in US EPA Method TO-4. The monitoring stations were located between remediation areas and potential downwind receptors (residences). Before initiating remedial activities, baseline (background) ambient PCB air levels were established. Twelve background samples were collected in the vicinity of the remediation area between October 7, 2004 and October 15, 2004. Three samples were collected from one upwind location (Air-1) and nine samples were collected from three downwind locations (Air-2, Air-3 and Air-4) of remedial activities. Concentrations of PCBs in air downwind of remedial activities averaged 0.009 mcg/m3; upwind air concentrations averaged 0.038 mcg/m3. During excavation activities, an air sample was to be collected once per day at each of the three downwind sample locations and analyzed for PCBs. PCB concentrations in these air samples ranged from non-detect to 0.227 mcg/m3. The downwind air concentration for PCBs during remedial activities at Turtle Cove averaged 0.0088 mcg/m3. A value equal to one-half of the lowest reported value, or, 0.0003 mcg/m3, was used for samples reported as non-detect for PCBs. Three of the air samples exceeded the US EPA site-specific Contingency Action Level of 0.11 mcg/m3 (Air-2-46 with 0.227 mcg/m3; Air-2-63 with 0.134 mcg/m3 and Air-2-64 with 0.122 mcg/m3). One sample exceeded the US EPA site-specific Evaluation Action level of 0.07 mcg/m3 (Air-2-44 with 0.084 mcg/m3). Exceedences of the site-specific action levels occurred only at Air-2, located on the north side of Turtle Cove, nearest the remedial activities. Air monitoring stations Air-3 and Air-4 were located between the remedial activities and residential areas on the Akwesasne reservation. In all cases, following the notification of the exceedences, no immediate action was taken because the activity that was thought to have caused the exceedence had stopped.
Remedial measures taken to date should reduce overall exposures to PCBs in ambient air. The use of proper engineering controls, application of appropriate dust suppression methods, monitoring of ambient air for PCBs and implementation of a community air monitoring plan will continue during all future site-related remedial activities to monitor and minimize any potential exposures to PCBs in air. Ongoing soil remediation actions on the Akwasasne reservation include four air monitoring stations for fugitive airborne PCB-dust.
NYS DOH and ATSDR conclude that, although many actions have been taken that have reduced exposures to PCBs, some exposure at levels of health concern may continue to occur unless further actions are taken. The GM site in Massena remains a public health hazard because of the continuing presence of PCBs in Turtle Creek that may contribute to the PCB contamination of edible fish and wildlife. The RODs for both OU-1 and OU-2 have not been fully implemented. On- and off-site contamination remains and human exposures to PCB contamination are possible via several routes and pathways.
- On-site sources of groundwater contamination remain. Although some source removal has been done, migration of contaminated groundwater toward the St. Lawrence River has not yet been controlled. Remedial design of a groundwater collection trench between OU-2 and the St. Lawrence River has been initiated. The groundwater collection system would control off-site discharge of contaminated groundwater. Collected groundwater would be monitored. The necessity of a groundwater collection trench remedy is currently being re-evaluated based on the ongoing assessment of groundwater quality and hydrogeologic variables. Exposure to contaminants in drinking water is not expected, as groundwater is not being used as a drinking water source. The municipal water system has been extended to serve local residents previously relying on groundwater as their potable water supply source. The intake for the public water supply is several miles downstream of the GM site. GM facility workers obtain their drinking water through company-supplied bottled water. Intake water from the St. Lawrence River is used for process water needs.
- Most of the PCB-contaminated soil excavated during remedial activities has been shipped off-site to an approved disposal facility. The remaining soil containing low level PCBs has been excavated and consolidated on-site. The stockpiled soils are contained within engineered containment cells that are lined, bermed, capped, and inspected regularly. Interim remedial measures such as paving and capping have effectively reduced the potential for exposure to residual contaminated soils. The Remedial Action Plan for OU-2 has not been finalized.
- Remediation of the St. Lawrence and Raquette Rivers and Turtle Cove has effectively reduced the potential for exposure to contaminated sediments and riverbank soils in these areas. However, areas downstream of the Raquette River remedial work should be considered for additional sediment sampling. Discussions between GM and the US EPA, NYS DEC, NYS DOH and SRMT continue regarding additional delineation requirements for sediments containing greater than 1.0 mg/kg along the Raquette River. Additionally, contaminated sediment and bank soil remains along Turtle Creek. Exposure to contaminated sediments and associated soils along Turtle Creek may occur during recreational use of this area. Activities to remediate the Mohawk Uplands began in 2007. Access to several private properties in this area has been obtained, and negotiations are continuing to obtain access to a final parcel in this area for delineation and remediation activities.
- Fish and wildlife, including snapping turtles and waterfowl, may continue to be contaminated. Exposure to PCBs may occur through the ingestion of contaminated fish or wildlife. Consumption advisories remain in effect and are evaluated and updated periodically if new data become available for a specific water body. Fish and wildlife advisories were most recently issued by the NYS DOH in 2007.
- In the past, PCBs were detected in air samples at levels slightly above the background range for rural continental areas. The average PCB air concentrations during remedial activities was less than the average background PCB air concentration of samples collected prior to remediation. Measures to control fugitive dust are an ongoing requirement of remedial work.
- Since ongoing sources of groundwater contamination exist on-site, migration of contaminated groundwater toward the St. Lawrence River must be controlled. Remedial design of a groundwater collection trench between OU-2 and the St. Lawrence River has been initiated. The necessity of a groundwater collection trench remedy is currently being re-evaluated based on the ongoing assessment of groundwater quality and hydrogeologic variables.
- Removal or containment of contaminated areas in OU-1 and OU-2, as defined in the RODs issued for this facility, should be completed to eliminate potential exposure to contaminants in on-site and off-site soils.
- PCB-contaminated sediment and soil in off-site areas not yet remediated should be removed.
- The current NYSDOH fish advisories should remain in effect until post-remedial sampling indicates that they can be removed or relaxed. A post-remediation fish sampling plan should be developed and executed (with NYSDOH and NYSDEC guidance and review) in order to evaluate site impacts on fish PCB levels and the NYSDOH fish advisories. Although some remedial actions have been completed, it is our understanding that there is still an unresolved question regarding potential movement of site PCBs offsite into Turtle Creek, Turtle Cove, and the St. Lawrence River. This issue should be resolved before a fish sampling plan is devised and executed
- Air sampling for PCBs and measures to control fugitive dust emissions during remedial activities should continue for the protection of the downwind community from potential exposures. Sample locations and collection techniques should be chosen carefully to monitor and minimize nearby residents' exposure to PCBs.
The Public Health Action Plan for the GM site describes the ongoing actions taken by ATSDR, NYS DOH, US EPA, or NYS DEC following completion of this health consultation. The purpose of the Public Health Action Plan is to ensure that this health consultation not only identifies public health hazards, but provides a plan of action designed to mitigate health hazards and prevent adverse human health effects resulting from present and/or future exposures to contaminants at or near the site. ATSDR and/or NYS DOH will ensure that this plan is implemented. The ongoing public health actions for the GM site are as follows:
- The current NYSDOH fish advisory remains in effect. The NYSDOH fish advisory will be revised (as warranted) when appropriate fish data are made available.
- As required by the OU-1 and OU-2 RODs, remedial actions to reduce and or eliminate PCB-contaminated media are ongoing. US EPA has provided oversight for all remedial activities, including the 2002/03 removal of contaminated sediment and associated soils from the Raquette River on the south edge of the GM property, the 2004/05 removal of contaminated sediments from Turtle Cove, and the 2007 removal of contaminated soils from the Mohawk Uplands. NYS DOH and NYS DEC will continue to work with US EPA, GM and the SRMT to facilitate implementation of the remaining ROD requirements.
- NYS DOH, along with US EPA and NYS DEC, has reviewed and will continue to review results of air monitoring data collected in conjunction with ongoing remedial actions. Resulting information will be used to evaluate whether additional air monitoring is necessary following the completion of remedial measures at the site.
- NYS DOH and ATSDR have coordinated efforts with the SRMT Environment Division to advise the public health professional and local medical community of the nature and possible consequences of exposure to contaminants from the GM site. NYS DOH and ATSDR will continue to work with the SRMT Environmental Division representatives to address their health and environmental concerns.
Agency for Toxic Substances and Disease Registry (ATSDR) and the New York State Department of Health (NYS DOH), 1995. Exposure to PCBs from Hazardous Waste Among Mohawk Women and Infants at Akwesasne. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Services. Grant #H75/ATH 290025-01
Agency for Toxic Substances and Disease Registry (ATSDR). 1999. Public Health Assessment for General Motors (Central Foundry Division), Massena, St. Lawrence County, New York. CERCLIS No. NYD091972554 U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Services.
Agency for Toxic Substances and Disease Registry (ATSDR). 2000. Toxicological Profile for Polychlorinated Biphenyls. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Services.
BBL Environmental Services, Inc. 2006. Draft Cove Remedial Action Completion Report, General Motors Powertrain, Massena, New York
Fitzgerald, E.F., D.A. Deres, S. Hwang, B. Bush, B. Yang, A. Tarbell, and A. Jacobs. 1999. Local Fish Consumption and Serum PCB Concentrations among Mohawk Men at Akwesasne. Environmental Research. 80: S97-S103.
New York State Department of Health (NYSDOH). 2007. 2007-2008 Health Advisories; Chemicals in Sportfish and Game. Center for Environmental Health, Division of Environmental Health Assessment. Troy, New York. http://www.health.state.ny.us/nysdoh/environ/fish.htm
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New York State Department of Health
Bureau of Environmental Exposure Investigation
Fay S. Navratil
Public Health Specialist
John G. Sheehan
Public Health Specialist, Retired
Sharon P. McLelland
Public Health Specialist
Beth K. Guidetti
Public Health Specialist
Donald W.R. Miles
Steven M. Bates
Assistant Bureau Director
Agency for Toxic Substances and Disease Registry
Senior Regional Representative - Region 2
Office of Regional Operations
Gregory V. Ulirsch, Ph. D.
Technical Project Officer
Environmental Health Engineer
Superfund Site Assessment Branch
Division of Health Assessment and Consultation
Regional Representative - Region 2
Office of Regional Operations