| Site Type: Long Term/National Priorities List (NPL) |
Map this site in Cleanups in My Community
| Concord,  Massachusetts|
| Middlesex County
| Street Address: ||2229 MAIN STREET |
| Zip Code: || 01742 |
| Congressional |
| EPA ID #: ||MAD062166335 |
| Site ID #: ||0100550 |
| Site Aliases: ||Starmet Corporation|
| Site Responsibility: ||Potentially Responsible Parties |
| NPL LISTING HISTORY |
| Proposed Date ||07/27/2000|
| Final Date ||06/14/2001 |
The Nuclear Metals, Inc. (NMI) property is located on a 46.4-acre parcel located at 2229 Main Street in Concord, Middlesex County, Massachusetts. The facility includes five interconnected buildings, a paved parking area, a sphagnum bog, a cooling water recharge pond, and a holding basin. The topography of the property slopes down to the north. The property is bordered to the north by Main Street, commercial and residential properties, and the Assabet River; to the east by woodland and residential properties; to the west by woodland and commercial/industrial properties; and to the south by woodland and residential properties.
In 1958, NMI began operating a manufacturing facility on previously undeveloped land. Nuclear Metals, Inc. produced depleted uranium (DU) products, primarily as penetrators for armor piercing ammunition. They also manufactured metal powders for medical applications, photocopiers, and speciality metal products, such as beryllium tubing used in the aerospace industry. From 1958 to 1985, NMI discharged wastes to an unlined holding basin. Cast depleted uranium ingots or billets were jacketed in copper, which were heated and extruded into long rod stock. The extruded depleted uranium rod had a resulting thin layer of copper coating, which was removed in a nitric acid pickling operation. During the pickling process, "small quantities" of copper and uranium were dissolved in the nitric acid. The spent nitric acid solution was collected, neutralized with a lime slurry, and then discharged to the unlined, in-ground holding basin. The discharge to the holding basin ceased in 1985 when NMI began using an acid closed-loop recycling process.
NMI handled natural and depleted uranium, thorium and thorium oxide originally under license to the Nuclear Regulatory Commission (NRC) but later (from 1997 to 2011) under the Massachusetts Department of Public Health Radiation Control Program (MADPH-RCP). In addition to radioactive materials, NMI handled other hazardous substances such as: sulfuric and nitric acids for process activities; trichloroethene (TCE), tetrachloroethene (PCE), and 1,1,1-trichloroethane (TCA) as solvents (1,4 dioxane also used in process as a stabilizer for TCA); zirconium; magnesium; beryllium; acetone; hydrogen peroxide; flammable gases (propane and acetylene); and Poly Chlorinated Bi-phenyls (PCBs). Operation and maintenance of the facility required the use of cutting oils for milling operations, hydraulic oils for operation of heavy presses, industrial cleaners and degreasers, air filters, and fuel oil for winter heating. In addition, the facility had on-site electrical transformers.
On October 1, 1997, NMI was renamed Starmet Corporation. Starmet, its subsidiaries, affiliates, and related entities (collectively, the Starmet Parties) continued to perform small scale operations at the Site through October 2011. Starmet officially vacated the property on November 2, 2011. The Radioactive Materials License was terminated by the MADPH-RCP on November 8, 2011.
In October 2014, EPA proposed a final remedy for the cleanup of soil, sediment and groundwater contamination at the site which generally includes:
The proposed plan will be described in fuller detail at a public information session on November 12 at 6:30 pm and oral comments can be made on the proposed plan at the public hearing on December 10 at 6:30 pm. Both events will be held at Concord Town Hall at 22 Monument Square in Concord, MA. Written comments can be made during the public comment period for the proposed plan which will begin on November 13 and end at midnight on December 15. The Proposed Plan can be found at: http://www.epa.gov/region1/superfund/sites/nmi/568091.pdf
- Excavation and off-site disposal of approximately 82,500 cubic yards of contaminated sediments, and non-Holding Basin soils located throughout the site;
- In-Situ stablization of DU contaminated soils in the Holding Basin using Apatite II injection, encapsulation of the Holding Basin using a vertical barrier wall and sub-grade cover, and filling the Holding Basin with clean soil to grade;
- Ex-situ treatment of VOCs and 1,4 dioxane in overburden and bedrock groundwater;
- In-Situ treatment of DU and natural uranium in overburden and bedrock groundwater, respectively, using Apatite and/or Zero-Valent Iron; and
- Long-term monitoring of groundwater and institutional controls to 1) restrict excavations in the Holding Basin Area; 2) prohibit use of contaminated groundwater until cleanup levels are met; and 3) require evaluation of vapor intrusion risks and, if necessary, installation of vapor mitigation systems should future structures be built above the VOC plume before cleanup levels are met.
Threats and Contaminants
Neutralized nitric acid solution containing dissolved copper and depleted uranium was discharged to an unlined Holding Basin between 1958 and 1985. Various facility drain lines from the buildings also appear to have discharged to the Holding Basin and a cooling water recharge pond and sphagnum bog on site. The primary receiving media were unsaturated and saturated soil below, adjacent, and surrounding the Holding Basin, and groundwater below the Holding Basin. Primary contaminants in the overburden groundwater are chlorinated VOCs, 1,4-dioxane, and depleted uranium. Naturally isotopic uranium has also impacted the on-property bedrock groundwater in excess of the federal Maximum Contaminant Level (MCL) of 30 ug/ml. In addition, the extent of contamination in sediments in a cooling water recharge pond and a sphagnum bog on the property is largely defined by areas where copper, PCBs, and/or uranium exceed risk-based cleanup levels. Poly Chlorinated Bi-phenyls (PCBs) have been found in various soils and sediments on-site. The on-site buildings and structures are severely contaminated with depleted uranium and other hazardous substances.
The cleanup approach has been one where many removal actions have taken place prior to the final remedy being chosen at the site, including:
The remaining contamination at the site will be addressed as part of the Record of Decision for the final remedy of the Site.
- In 1998, Nuclear Metals, Inc. conducted a voluntary partial cleanup of contaminated soils under The Massachusetts Department of Environmental Protection (MADEP) oversight. The partial cleanup consisted of excavation and transportation off site of approximately 8,000 cubic yards of soil contaminated with depleted uranium and copper. The cleanup halted in late 1998 when Nuclear Metals determined that the cleanup level set by MADEP could not be met without excavating significantly more material;
- In April 2002, USEPA conducted a Time-Critical Removal Action that included partial excavation and removal of metallic debris and drums, regrading of soils and the installation of a temporary cover system (cap) over the Old Landfill. The Holding Basin was backfilled with six feet of clean cover fill and capped with a polyethylene cover. In addition, a fence was erected around the Old Landfill. These caps were installed as an interim action, until a final remedy could be selected and implemented at the Site;
- From September 2005 through February 2006, MassDEP performed a removal action which included the removal and off-site disposal of almost 3,800 drums of depleted uranium and other waste materials from the from the facility buildings
- Between January and September 2008, EPA conducted a second Time-Critical Removal Action that included the removal and off-site disposal of hazardous materials which may have presented a fire or chemical hazards risk, materials that may have increased the risk of accelerating a fire due to chemical reactivity or explosion, and/or a risk to personnel involved in firefighting or response activities; and
- A NTCRA initiated in late 2011 and scheduled to be complete by the end of 2015 to remove all radioactive, flammable and hazardous equipment and material from the facility buildings and demolish the buildings.
Response Action Status
|Initial Action ||A time-critical removal assessment was conducted to determine if buried drums on site contain hazardous material. Two areas containing buried drums and other laboratory equipment were located during the removal assessment: one in a fenced-in area adjacent to the holding basin and cooling water pond, and contains approximately 70 drums; the other, called the "old landfill" contains an unknown number of drums and laboratory equipment. A time-critial removal action was conducted in 2002 which included: 1) installation of fencing around the "old landfill" area where buried drums are located; 2) regrading and capping of the "old landfill" area; and 3) installation of a liner in the holding basin to eliminate fugitive dust and reduce the leaching of contaminated soils into the groundwater. Sampling and analysis of soils in the holding basin was conducted in September 2001 to fill data gaps in previous sampling efforts and to determine if data from past sampling efforts performed by Starmet are comparable to EPA data. In June 2002, EPA assumed the groundwater monitoring program previously performed by Starmet. During the June 2002 sampling event, EPA also sampled sediment and surface water on-site and in the Assabet River. EPA sampled the groundwater monitoring wells again in July 2003 before turning site work over to Potentially Responsible Parties. |
|Remedial Investigation/Feasibility Study ||Remedial Investigation field work began in 2004 and is now complete. The ecological and human health risk assessments and the Remedial Investigation and Feasibility Study Reports have all been finalized . For up to date information, go to www.nmisite.org, which is maintained by the Potentially Responsible Parties' consultants. |
|second time-critical removal action ||In January 2008, EPA began a second time-critical removal action to address the lab chemicals and various other flammable/hazardous materials inside the facility buildings. Material removed from the facility was disposed of off-site. This removal action was completed in September 2008. The removal action was the resulting action from a fire that occurred at the facility in June 2007. The town of Concord, MA fire department requested assistance from EPA to address the flammable and hazardous materials within the facility that pose a risk of fire or explosion. |
|Non-Time Critical Removal Action (NTCRA) ||In February 2008, EPA issued an EE/CA to evaluate alternatives to address the contaminated facility buildings. In April 2008, EPA issued a fact sheet seeking public comment on EPA's proposal to demolish the facility buildings on site. The public comment period ended on June 12, 2008, After the public comment period, EPA signed an Action Memorandum on September 23, 2008, authorizing the demolition of contaminated buildings at the Nuclear Metals Superfund Site. On June 20, 2011, an Administrative Order on Consent for the NTCRA was reached between EPA, Textron, Inc., Whittaker, Corp, and the Army and Department of Energy. Under this agreement, the private parties are required to provide security for the building prior to demolition, remove all building contents, and demolish and dispose of all buildings and debris. Concrete building slabs will remain in-place so as not to disturb potentially-contaminated underlying soil. Sumps and depressions in the slab will be filled and slabs will be entirely overlain with a short-term cap and will be addressed under the final remedy for the site selected in the Record of Decision and proposed in the Proposed Plan. EPA expects this removal action to be completed by the end of 2015. The estimated cost for this NTCRA is $63.9 million. |
|MADEP Response Action ||In 2004, the MassDEP and the United States Army (“Army”) entered into an agreement whereby the Army financed the removal of approximately 3,800 drums of depleted uranium and other waste materials that were stored at the Site. MassDEP performed this drum removal from September 2005 to March 2007. |
Removal of 8,000 cubic yards of soil from the holding basin by Starmet under MADEP oversight has reduced the threat of potential exposure at the site. Lining of the holding basin has reduced potential exposure to contaminated dust, and installation of a fence and capping of the landfill has reduced the potential exposures to nearby residents as well. Removal of more than 3800 drums of depleted uranium and other materials from the facility by MADEP with Army funding has also reduced the threat of potential exposure and threat of release of contaminants at the site. Two time-critical removal actions have been conducted at the site that prevent contact with hazardous and radioactive material: 1) in 2002, EPA capped the "old landfill" area of the site, installed a fence around the area, and lined a holding basin containing depleted uranium; 2) in 2008, EPA removed hazardous and radioactive materials from the facility buildings to prevent release of those materials into the environment, 3) a NTCRA was initiated in 2011 to remove all radioactive, flammable and hazardous equipment and material from the facility buildings and demolish the buildings; and 4) in October 2014, EPA proposed a final remedy for the cleanup of soil, sediment and groundwater contamination at the site.
Current Site Status
A time-critical removal action was initially conducted from late 2002 to 2003 to prevent the direct contact threat with the contaminated surface soils located in the "old landfill" area, and to reduce the infiltration of precipitation into the holding basin soils. In June 2003, EPA also negotiated an agreement with five potentially responsible parties including: U.S. Army, U.S. DOE, Whittaker Corporation, MONY LIfe Insurance Co., and Textron, Incorporated, for the performance of a Remedial Investigation/Feasibility Study (RI/FS), which includes the performance of an Engineering Evaluation and Cost Analysis (EE/CA). A lien has been recorded on the Starmet property at 2229 Main Street in Concord. The RI/FS was completed in October 2014 and a Proposed Plan for the final remedy for the site has been prepared for public comment (see below for a link to the Proposed Plan). The public comment period begins on November 13 and ends at midnight on December 15, 2014.
In April 2004, the state reached an agreement with the Army to remove the more than 3800 drums of depleted uranium and other materials from within the facility. The state, under contract with a private contractor, began shipments of drums and other material to the Envirocare waste disposal facility in Clive, Utah in September 2005. The state removal work was completed in March 2007.
A second time-critical removal action which consisted of removing hazardous and flammable material from within the facility was performed in 2008. This removal action resulted from a fire that occurred at the facility in June 2007. After the fire, the town of Concord, MA fire department requested assistance from EPA to address the flammable and hazardous materials within the facility that pose a risk of fire or explosion.
In February 2008, EPA issued an Engineering Evaluation/Cost Analysis (EE/CA) to evaluate alternatives to address the contaminated facility buildings. In April 2008, EPA issued a fact sheet seeking public comment on EPA's proposal to demolish the facility buildings on site. The public comment period ended June 12, 2008. After the public comment period, EPA signed an Action Memorandum on September 23, 2008, authorizing the demolition of contaminated buildings at the Nuclear Metals Superfund Site as a Non-Time Critical Removal Action (NTCRA). Under this removal action all building contents will be removed, followed by the demolition and disposal of all buildings and debris. Concrete building slabs will remain in-place so as not to disturb potentially-contaminated underlying soil. Sumps and depressions in the slab will be filled and slabs will be entirely sealed and the underlying site soils will be addressed as part of the final remedy for the site.
On June 20, 2011, an Administrative Order on Consent for the NTCRA was reached between EPA, Textron, Inc., Whittaker, Corp, and the Army and Department of Energy. On November 1, 2011, the remaining employees at the facility vacated the site. The site is now controlled by the private party general contractor, demaximis, inc. EPA anticipates the NTCRA will be completed by the end of 2015. All waste materials are being sent off-site for disposal, with the majority of the waste going to the U.S. Ecology facility in Idaho. The estimated cost for this NTCRA is $63.9 million.
In October 2014, EPA proposed a final remedy for the cleanup of soil, sediment and groundwater contamination at the site.
Links to Other Site Information
Newsletters & Press Releases:
Federal Register Notices:
Reports and Studies:
Concord Public Library, Concord, MA
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: ||Melissa Taylor |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code OSRR07-4
Boston, MA 02109 - 3912
|Phone #: ||617-918-1310 |
|E-Mail Address: ||firstname.lastname@example.org |
|EPA Community Involvement Coordinator: ||Kelsey O'Neil |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code ORA01-1
Boston, MA 02109 - 3912
|Phone #: ||617-918-1003 |
|E-Mail Address: ||email@example.com |
|State Agency Contact: ||Garry Waldeck |
|Address: ||MA Department of Environmental Protection (MA DEP)|
One Winter Street
Boston, MA 02118
|Phone #: ||617-348-4017 |
|E-Mail Address: ||firstname.lastname@example.org |