Description of Surface Projects

During initial environmental studies, the Brookhaven National Laboratory (BNL) site was subdivided geographically into seven Operable Units (OU). Shortly thereafter, two of them were combined to form OU II/VII. The main Operable Units dealing with soil contamination are OU I and OU II/VII. Operable Unit IV also addresses some soil contamination.

Operable Unit I was originally defined as a 950-acre area in the southeastern part of the BNL site. Later, to facilitate the cleanup process, similar types of contamination from different Operable Units were grouped together. Soils contaminated with radioactive materials from areas originally included in OU II/VII, IV and VI are being cleaned up under OU I because they have similar contaminants.

Operable Unit II/VII is located in the central, developed portion of the BNL site. It consists of four "areas of concern" - the Waste Concentration Facility, aerial radiation survey locations, the former Low Mass Criticality Facility, and storage yards for the Alternating Gradient Synchrotron.

Operable Unit IV is also located in the central, developed portion of the BNL site. Its area of concern is the Central Steam Facility. OU IV also addressed the Reclamation Facility and Sump Outfall Area, which has since been transferred to OU I (see below for more).

Operable Unit I

The principal soil contaminants in Operable Unit I are radioactive elements, primarily cesium-137 and strontium-90. Elevated levels of heavy metals are also found in some locations. All soil contaminants are confined to BNL property, and access to these areas is controlled as needed to protect employees and the public.

Radiologically contaminated soils

Former Hazardous Waste Management Facility (HWMF) - The largest volume of contaminated soil was located at the HWMF. It was used from 1947 to 1997 as a central receiving, processing and storage facility for radioactive and hazardous waste generated at BNL. The primary soil contaminants at the HWMF were cesium-137 and strontium-90. Elevated levels of heavy metals (mercury and lead) were also present in isolated areas. 

Cleanup at the HWMF began during the summer of 2003 with the controlled demolition of several building structures.  Workers are taking down buildings piece-by-piece to minimize dust production and other unnecessary exposure.  After the buildings and (if necessary) foundations are removed, approximately 15,000 cubic yards of contaminated soil will be excavated from about 13 acres of land.  Soil excavation is scheduled for the spring of 2004.

Reclamation Facility and Sump Outfall Area - Radioactive elements were found in soils at the reclamation facility and in a sump outfall east of the facility. This facility was used from the late 1950s through the late 1960s to clean radioactive contaminants from clothing and equipment. It is no longer used for decontamination, although it is still in use for routine laundry. Water from decontamination of equipment was discharged at the sump outfall area until late 1969. Soils at the sump outfall contain elevated levels of cesium-137 and strontium-90, as well as minor concentrations of other radioactive elements. The contaminated soil will be excavated and shipped off site for disposal.

Wetlands

Upland Recharge/Meadow Marsh Area - This area was used in sewage treatment experiments from 1973 to 1978. Sediments in two of the manmade basins contain elevated levels of heavy metals such as copper, zinc and aluminum. The Meadow Marsh ponds were cleaned up in the summer of 2003 and now function as a habitat for the Tiger Salamander population.

Storm Recharge Basins - These two basins are used to recharge runoff that enters BNL's storm sewer system. Their sediments contain elevated levels of heavy metals such as copper and lead, as well as organic chemicals.

Wooded Wetland - This area is located adjacent to the current landfill and received runoff from that landfill. Sediments here contain elevated levels of metals such as aluminum.

Metal concentrations in these wetlands are below those of human health concern, according to federal guidelines. However, there is an ecological risk to the New York State endangered tiger salamander, which uses these areas for breeding.

Two Upland Recharge/Meadow Marsh basins will be excavated and reconstructed as part of BNL's cleanup program. The storm recharge basins will continue to operate and will be monitored. A Tiger Salamander Habitat Management Plan will detail the routine maintenance required at these basins. BNL will conduct annual monitoring of surface water and sediments at the Wooded Wetland.

Ash pit

Both heavy metals and radioactive elements were found in an ash pit, used from 1943 to 1963 to dispose of incinerator ash. Levels of contaminants were typical of those found in incinerator ash. Radioactive elements found here were common in incinerator ash and were unrelated to research operations at BNL. This area was cleaned up in the summer of 2003.  The ash pit cleanup involved removing some trees, backfilling soil to even out the grade, placing 12 inches of topsoil to cover the ash, and reseeding the area with native grasses.  For more information, see http://www.bnl.gov/erd/Surface/ashpit.html.

Removal actions

A removal action is an accelerated cleanup response to a known contamination source. The following areas of concern in Operable Unit I are being or have been addressed as removal actions:

Former and Interim Landfills - These closed landfills, including a slit trench, were a source of groundwater contamination from volatile organic compounds (VOCs) and strontium-90. The landfills, which cover nine acres of land, were used from 1947 to 1966 for the disposal of general waste, construction debris and chemicals. These landfills have been capped.

Current Landfill - This closed eight-acre landfill was a source of VOC and tritium groundwater contamination. It was used from 1967 to 1990 for the disposal of the same materials as the other two landfills. The current landfill is no longer in operation for waste disposal and has been capped.

Chemical Holes - These 55 waste pits were a source of VOC and strontium-90 groundwater contamination. They were used from the late 1950s to 1981 for the disposal of biological waste, chemical containers and glassware. These holes were excavated in 1997. Soil and debris are currently being packaged and shipped off site for disposal.

Groundwater - VOCs from the current landfill and the HWMF have migrated into the groundwater. Rainwater percolating through contaminated soil can pick up the VOCs and transport them into the groundwater. An air stripping system began operating in December 1996 to treat this groundwater. It has treated over 1 BILLION gallons of groundwater, and has removed nearly 200 pounds of VOCs.

Operable Unit II/VII

Waste Concentration Facility

Cesium-137 and strontium-90 contamination was found in soils here. This facility has been used since 1949 for reducing the volume of liquid radioactive waste prior to disposal. It is still an operational facility. Three large storage tanks were in use here from 1949 to 1987, and were removed in 1994. Additional tanks and piping still remain. These tanks and piping, along with radiologically contaminated soils, will be removed as part of BNL's environmental cleanup.

Lawns and Landscaping Soils

Low levels of cesium-137 were found in soils near several buildings in the center of the BNL site. Soils from the HWMF were used as landscaping and fill material at these locations. These soils began being excavated in May 2000 for off-site disposal. The excavations were completed in September 2000. The excavated areas were backfilled with clean soil and will be reseeded in the spring of 2001.

Two other areas at BNL were examined for radiological contamination. The Alternating Gradient Synchrotron (AGS) storage yards hold steel and equipment that is being stored for potential reuse at the AGS. The former Low Mass Criticality Facility was used for research from the mid-1950s to the mid-1960s, and for temporary drum storage from June 1983 to March 1984. No contamination at levels of human health concern was found at these two locations. No cleanup of these areas is required. Institutional controls and monitoring will continue.

Brookhaven Linac Isotope Producer (BLIP)

Low levels of tritium and sodium-22 were found in soil and groundwater near BLIP. These contaminants are generated by "soil activation" during normal BLIP operations. In order to prevent these contaminants from migrating into area groundwater, a silicon grout has been applied to an area of soil beneath the BLIP building. This grout will "lock" contaminants in place, preventing them from leaching into the groundwater. A cap is also in place to prevent rainwater from percolating through the contaminated soil.

Operable Unit IV

Central Steam Facility

This facility supplies heating and cooling to all major BNL buildings and includes aboveground fuel tanks connected to a boiler building (Building 610) by aboveground and underground pipes. In the past, the Central Steam Facility included underground fuel storage tanks.

In November 1977, a spill of about 25,000 gallons of a waste oil/solvent mixture occurred. The spill pooled on about 1.2 acres and was contained with sand berms. At that time, portable pumps were used to clean up as much as possible. They recovered an unknown quantity of the oil and solvent.

A 5,000-gallon underground storage tank, associated piping and visibly contaminated soil were removed from this area in October 1993. To address the volatile and semi-volatile contaminants remaining in soils and groundwater, an air sparging/soil vapor extraction system was installed. It became operational in November 1997. This system strips volatile and some semi-volatile contaminants from soils and groundwater into their vapor phase. The vapors are then extracted from the ground and filtered to remove the contaminants. To date, this system has removed approximately 24 pounds of chemicals from the spill area. Monitoring showed that, as of late 2000, levels of VOCs in area groundwater were below the drinking water standard. As a result, the system was shut down in January 2001. Groundwater monitoring will continue.  The five-year review of the Operable Unit IV treatment system is now available.