| Site Type: Long Term/National Priorities List (NPL) |
W. R. GRACE & CO., INC.(ACTON PLANT)
Map this site in Cleanups in My Community
| Acton; Concord,  Massachusetts|
| Middlesex County
| Street Address: ||50 INDEPENDENCE RD |
| Zip Code: || 01720, 01742 |
| Congressional |
| EPA ID #: ||MAD001002252 |
| Site ID #: ||0100350 |
| Site Aliases: ||Acton Plant, WR Grace|
| Site Responsibility: ||Federal, State, Potentially Responsible Parties |
| NPL LISTING HISTORY |
| Proposed Date ||12/30/1982|
| Final Date ||09/08/1983 |
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The W. R. Grace (Acton Plant) Superfund site is located in the towns of Acton and Concord, Massachusetts and is accessible via Independence Road. The W.R. Grace property is comprised of approximately 260 acres of land that includes several surface water bodies and various wetlands. The Site is bounded to the north in part by Fort Pond Brook and to the east and south by the Assabet River. Residential properties border the Grace site to the northeast, northwest, east and west and several Industrial properties border the site to the south and northeast. Industrial parks and a gravel pit border the site to the south.
The site had been the former location of the American Cyanamid Company and the Dewey & Almy Chemical Company. These companies produced sealant products for rubber containers, latex products, plasticizers, resins, and other products. W. R. Grace purchased the properties and operations from American Cyanamid and Dewey & Almy in 1954. The Grace operations at the W. R. Grace facility included the production of materials used to make concrete, container sealing compounds, latex products and paper and plastic battery separators. Effluent wastes from the manufacturing process were disposed of into several unlined lagoons (the Primary Lagoon, Secondary Lagoon, North Lagoon, and Emergency Lagoon), and solid and hazardous wastes were buried in or placed onto an on-site industrial landfill and several other disposal areas. These other waste sites included the Battery Separator Lagoons, the Battery Separator Chip Pile, the Boiler Lagoon, and the Tank Car Area. In addition, the by-products of some chemical processes were also disposed of in the Blowdown Pit. All discharges to the unlined pits were ceased by W.R Grace in 1980.
Since 1973, residents in South Acton have filed complaints about periodic odors and irritants in the air around the W. R. Grace plant. Sampling of public supply Wells Assabet l & 2 by the Town of Acton in 1978 indicated that these two municipal wells contained detectable concentrations of 1,1-dichloroethene or vinylidine chloride (1,1 DCE or VDC). As a result of these findings, the Town of Acton took the precautionary measure of temporarily closing the two wells. As part of an agreement and settlement between W.R. Grace and the Town of Acton, The Acton Water District (AWD), installed and continues to operate and maintain air stripper units which remove any volatile organic compounds that may be present in groundwater pumped from Assabet 1, Assabet 2, Scribner, Lawsbrook and Christofferson public drinking water supply wells. Prior to distributing potable water to the public, the AWD routinely treats and samples the water they provide to their users to ensure that all safe drinking water quality standards are met.
Threats and Contaminants
Groundwater is contaminated with Volatile Organic Compounds (VOCs) including 1,4 Dioxane, 1,1-DCE, benzene and vinyl chloride and inorganics/metals including arsenic, iron and manganese. Sediments in Sinking Pond and the North Lagoon wetland are contaminated with arsenic and manganese. The hazardous soils and sludges in the former waste disposal areas were contaminated primarily with arsenic and VOCs, including vinyl chloride, ethyl benzene, benzene, 1,1-dichlorethylene, and bis(2-ethylhexyl)phthalate. Cleanup and remediation of the soils and sludge disposal areas were completed in 1997. Approximately 173,000 cubic yards of contaminated materials were removed, treated with and properly disposed of.
Work on a Remedial Investigation, human health and ecological risk assessment and Feasibility study began in 1998 and were finalized on July 1, 2005. The purpose of these documents is the following: determine the nature and extent of groundwater, surface water and sediment contamination, determine if and where there are unacceptable human health or ecological risks and determine how to reduce unacceptable risks to acceptable levels.
On September 30, 2005, EPA issued a Record of Decision (ROD) for Operable Unit Three (OU3). A ROD documents the following: the areas of the site which need to be cleaned up, establishes the protective clean up levels for both human health and the environment, the clean up method(s) and approximate costs. This last phase (OU3) of clean up actions will remediate contaminated sediments in Sinking Pond and the North Lagoon Wetland, installation of a groundwater extraction treatment and reinjection system in the northeast area of the site and will also involve the design and construction of a groundwater extraction, treatment and surface water discharge system at the Landfill (southern) area of the site. Treatment processes for the landfill area system includes the extraction of contaminated groundwater, metals/inorganics precipitation photocatalytic oxidation and effluent discharge to Sinking Pond.
The site is being addressed in four stages: Interim Actions and three long-term operable unit (OU) remedial phases which focus on aquifer restoration:
(OU 1), soil removal and remediation, landfill and lagoon closures
(OU 2), residual soil contamination
(OU 3), on-site and off-site groundwater, surface water, sediments and wetlands.
OU 1 & OU 2 activities have been completed. OU 3 activities are currently ongoing
Response Action Status
|Initial Action ||The parties potentially responsible for site contamination removed hazardous storage tanks from the site in 1982 and 1983. |
|Aquifer Restoration ||The responsible party have installed and operated an Aquifer Restoration System (ARS) on the southern area of the site. This system pumps contaminated groundwater and then removes VOC contaminants via air stripping/volatilization. The ARS has been in operation since 1985 in an attempt to mitigate the discharge of contaminated groundwater to Assabet Wells #1 & 2, the Assabet River, Fort Pond Brook and various other water bodies. Supplemental engineering studies began in late 1998 to evaluate the effectiveness and capture zones of the ARS and to determine the full nature and extent of the remaining groundwater contamination. The 2005 ROD required groundwater extraction from different locations to be more effective and also requires additional groundwater treatment for metals/inorganics prior to effluent treatment to Sinking Pond. |
|Operable Unit One - Landfill and Lagoon Closure ||EPA's 1991 Clean Up Plan recommended the following: excavating and transporting for off-site incineration the highly contaminated material from the Blowdown Pit; excavating and stabilizing the material in the Blowdown Pit, the Primary Lagoon, Secondary Lagoon, North Lagoon, and Emergency Lagoon by mixing it with cement, lime, and fly ash to form a solid; excavating the soils from the Battery Separator Lagoons, Boiler Lagoon, and Tank Car area; placing both the stabilized and non-stabilized materials excavated from the site in the existing industrial landfill and covering these materials with a cap to prevent surface water or rain water from coming into contact with the buried contaminants; closing the Chip Pile area; modifying the Aquifer Restoration System to address emission controls; and extensive monitoring activities in each area. The design for this remedy (OU 1 & 2) was conducted in phases and completed in 1993. Remediation and construction was completed in June 1997. Just over 170,000 cubic yards of contaminated materials were removed and properly disposed of. |
|Groundwater Treatment ||Since 1985 W.R. Grace has maintained and operated a groundwater extraction, treatment and discharge system (the ARS) which removes volatile organic compounds from groundwater. From 1985 - 2008, the ARS has removed over 6000 pounds of total VOC's and pumped over 4,800 million gallons of contaminated groundwater.|
In July of 2005, the responsible party, W. R. Grace Inc., completed a Remedial Investigation/Feasibility Study and a human health & ecological risk assessment for onsite and offsite groundwater, surface water and sediments to determine the nature, extent, levels and threats of hazardous contaminants that were still present.
In March of 2010 the construction of the Northeast Area treatment system was completed and then became operational by April 2010. In December of 2010, W. R Grace submitted a final 100% Design for the Landfill Area treatment system.
Construction of the Landfill Area treatment system began in 2010 and the system became operational in May 2011. The landfill area treatment system continues to extract and treat contaminated groundwater in the landfill area. See Operable Unit Three below for more information.
|Operable Unit Three ||The final clean up actions at the W.R. Grace (Acton Plant) Superfund site consists of the following:|
- Cleanup of contaminated sediments and soil posing an unacceptable risk to human health and/or the environment in both Sinking Pond and the North Lagoon Wetlands.
- Targeted extraction and treatment of groundwater contamination from the Northeast Area and reinjection of the treated effluent back into the aquifer.
- Extraction and treatment of groundwater contamination in the Southeast & Southwest Landfill Areas. Construction and operation of a groundwater extraction, treatment and discharge system. Treatment processes for the landfill area system includes the extraction of contaminated groundwater from five extractioin wells, metals/inorganics removal with photocatalytic oxidation for destruction of VOCs. Treated effluent will then be discharged into Sinking Pond.
- Monitored natural attenuation in areas were groundwater contamination is not captured by the extraction systems.
- Institutional controls to prevent unacceptable exposures to contaminated groundwater until cleanup levels are met, and to protect against unacceptable future exposures to any wastes left covered/capped on the site.
- Long-term groundwater, surface water, and sediment monitoring and periodic five-year reviews of the remedy.
In August of 2006, EPA, MassDEP and W.R. Grace negotiated a settlement agreement known as a Remedial Design/Remedial Action Statement of Work. This settlement agreement was worth approximately $18 millions and requires W. R. Grace to implement and fund the clean up actions. From 2006 to 2010 numerous engineering design documents were submitted for review and approval to EPA, MassDEP, Acton Board of Health, Acton Water District and the local citizens group, ACES. All construction work associated with this Operable Unit was completed by 2012. see "Current Site Status" below for more information.
Removing the storage tanks, contaminated sludges and soils, and operating the existing aquifer restoration system have greatly reduced the potential for unacceptable exposures to hazardous substances, thus making the W. R. Grace site safer while the final clean up remedial design additional cleanup activities and subsurface investigations are underway. By September of 1997 over 173,000 cubic yards of contaminated materials were excavated, treated on-site by thermal treatment & solidification. Some of these highly contaminated materials were shipped off-site, for proper disposal. After the on-site contaminated materials were thermally treated and solidified, the inert material was then placed beneath an impermeable cap, in the on-site Industrial Landfill.
From 1985 - 2008, the ARS has removed over 6000 pounds of total VOC's and pumped over 4,800 million gallons of contaminated groundwater. On September 30, 2005, EPA issued the Record of Decision for the final phase of clean up for sediments and groundwater for the W.R. Grace site. In August of 2006, EPA, MassDEP and W.R. Grace negotiated and finalized a settlement agreement known as a Remedial Design/Remedial Action Statement of Work.
Over time, operation of the ARS, the Northeast Area and Landfill Area groundwater treatment systems greatly reduced both the concentrations and extent of groundwater contamination over time. The excavation and proper off-site disposal of contaminated sediments from Sinking Pond and the North Lagoon Wetlands addressed the unacceptable risks to human health and the environment. See the below section entitled: "Current Site Status" for additional details and information.
Current Site Status
OU 1 and OU 2 activities at the site were completed by September 1997. Activities included the removal, solidification/stabilization, and placement/capping of contaminated soils and sludges into an on-site landfill. A Draft Preliminary Reuse Assessment was completed in September 2004. The first Five Year Review (a review of the protectiveness of the clean up) was completed for the site in September 1999 and a Second Five Year Review was completed in September 2004. A third Five Year Review was completed in September of 2009 and a fourth Five Year Review was completed in September of 2014. The results from all of the Five Year Reviews were consistent with one another and determined that the clean up actions are still protective of human health and the environment.
Based on the results of numerous extensive investigations, EPA prepared and released a Proposed Clean-up Plan to the public in July 2005. EPA then held an informational public meeting in July 2005 and a public hearing in August of 2005, at the Acton Town Hall to answer questions and receive public feedback on EPA's 2005 Proposed Clean Up Plan. After careful and extensive review of all public comments, EPA prepared and issued the second Record of Decision for the W.R. Grace site on September 30, 2005. The text of this September 2005 ROD is available to view via a link from the below section entitled: "Decision Documents."
Construction of the Northeast Area groundwater treatment system began in June 2009 and was completed in March of 2010. This system consisted of an extraction well, from which approximately 20 gallons per minute (GPM) of contaminated groundwater was withdrawn from 211 feet below the ground surface (fbgs). The system removed Volatile Organic Compounds (VOCs) and inorganics from groundwater and then the treated groundwater was re-injected back into the aquifer at 70 fbgs. The Northeast Area groundwater treatment system began operating in April of 2010. In September of 2013, EPA and MassDEP approved the shutdown of the Northeast Area Treatment system because the system achieved the design objectives specified in the 2005 Record of Decision.
In August of 2006, EPA, MassDEP and W.R. Grace negotiated a settlement agreement known as a Remedial Design/Remedial Action Statement of Work. As required by the RD/RA Statement of Work, from 2006 to 2010 numerous engineering design documents were submitted for review and approval to EPA, MassDEP, Acton Board of Health, Acton Water District and the local citizens group, ACES.
Construction of the foundation and building for the Landfill Area groundwater treatment system began in September 2010, and the installation of the treatment system equipment was complete by April 2011. This treatment system began operation on May 2, 2011, and will continue to operate until groundwater cleanup levels are met and groundwater no longer presents an unacceptable risk. This treatment system extracts approximately 50-55 GPM of contaminated groundwater from five different extraction wells located in the vicinity of the Industrial Landfill at various depths. Contaminated groundwater is treated to remove inorganics (metals), VOCs and 1,4 Dioxane. The treated effluent is then discharged into Sinking Pond and is sampled on a periodic basis to ensure continued compliance with discharge standards.
Numerous studies and sampling determined that there were unacceptable human health and ecological risks from continued exposure to arsenic and manganese contaminated sediment. The contaminated sediments were located within the perimeter of Sinking Pond and within the North Lagoon Wetland. The cleanup actions for sediment were implemented between June and November 2011 and included the removal and proper off-site disposal of contaminated sediment. A total of 8,100 cubic yards of contaminated sediment was removed from Sinking Pond and properly disposed off site. A total of 2,040 cubic yards of contaminated sediment was removed from the North Lagoon Wetland and properly disposed off site . Results from the post excavation confirmation sampling determined that the appropriate and protective cleanup levels were achieved within the remaining sediment. Certified clean fill was sampled and then brought in to replace the removed contaminated sediment. Various native trees, vegetation and grasses were planted in wetland and upland locations in order to restore these areas to their natural condition over time. Spring and fall inspections of these replanted areas began in 2012 and will continue until 2017. This will ensure that the replanted trees, vegetation and grasses will survive and become established.
In March of 2010 the construction of the Northeast Area groundwater treatment system was completed and it became operational in April 2010. In December of 2010, W. R Grace submitted a final 100% Design for the Landfill Area treatment system. Construction of the Landfill Area treatment system began in the spring of 2011 and was deemed operational and functional in May 2012. The sediment dredging and removal in Sinking Pond and the North Lagoon Wetlands was completed in 2011. Approximately 11,900 tons of contaminated sediments were removed and properly disposed of offsite.
Although construction of the final clean up actions has been completed, EPA & MassDEP will continue to oversee the following site activities:
· Continued monitoring, operation and proper maintenance of the Landfill Area treatment systems,
· Continued oversight of the annual groundwater monitoring and sampling programs,
· Bi-annual inspection of the restored wetlands and uplands,
· A thorough review of clean up actions every five years to ensure that the clean up actions remain protective of both human health and the environment, and
· Continued operation and proper maintenance of the capped Industrial Landfill.
(See Photograph Links Below)
Links to Other Site Information
Maps and Photos:
Newsletters & Press Releases:
Federal Register Notices:
Reports and Studies:
|Press Releases about this project   |
|Community Update, December 2002 (455 KB)   |
| Public Meeting Presentation on W R Grace (Acton Plant), Operable Unit 3, Proposed Cleanup Plan, July 19, 2005 (1.8MB)   |
|Community Update, October 2007 (771 KB)   |
|Community Update, July 2009 (1.03 MB)   |
|Community Update, May 2011 (960 KB)   |
|Site Information Session Powerpoint Presentation, May 18, 2011 (4.28 MB)   || |
|Fact Sheet: 1,4-Dioxane at the W.R. Grace (Acton Plant) Site, March 2012 (4.05 MB)   |
|Site Update, February 2013 (2.19 MB)    |
|Five Year Review Report, September 29, 1999 (785KB)   |
|Second Five Year Review Report, September 28, 2004 (6.97 MB)   |
|Proposed Plan for OU 03, July 2005 (2.6MB)   |
|Remedial Design/Remedial Action Statement of Work, OU03, August 30, 2006 (3.5 MB)   |
|Third Five Year Review Report, September 23, 2009 (4.8 MB)   |
|Northeast Area Groundwater Operations & Maintenance Plan, June 1, 2010 (57 MB)   |
|Public Health Assessment, April 5, 2011 (3.44 MB)   |
|Sediment Demonstration of Compliance and Maintenance Plan, November 2011 (4.43 MB)   |
|Landfill Area Groundwater Operation and Maintenance Plan, April 1, 2012 (1.67 MB)   |
|Final Sediment Demonstration of Compliance and Maintenance Plan, April 1, 2012 (42.6 MB)   |
|Final Sediment Construction Summary and Final Sediment Remedial Action Report, June 2012 (50.2 MB)   |
|Final Landfill Area Groundwater Remedial Action (RA) Report, September 25, 2012 (14.0 MB)   |
|2012 Monitoring Program Report for OU 03, December 20, 2012 (24.4 MB)   |
|Operable Unit (OU) 3 Monitoring Program Report, December 20, 2013 (29.1 MB)   |
|Fourth Five Year Review, September 23, 2014 (15.2 MB)   |
Acton Public Library, 486 Main Street, Acton, MA 01720
OSRR Records and Information Center, 1st Floor, 5 Post Office Square, Suite 100 (HSC), Boston, MA 02109-3912 (617) 918-1440
|EPA Remedial Project Manager: ||Derrick Golden |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code OSRR07-1
Boston, MA 02109-1367
|Phone #: ||617-918-1448 |
|E-Mail Address: ||firstname.lastname@example.org |
|EPA Community Involvement Coordinator: ||Sarah White |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code ORA20-1
Boston, MA 02109-1367
|Phone #: ||617-918-1026 |
|E-Mail Address: ||email@example.com |
|State Agency Contact: ||Jennifer McWeeney |
One Winter Street
Boston, MA 02108
|Phone #: ||617-654-6560 |
|E-Mail Address: ||firstname.lastname@example.org |