The U.S. Department of Energy (DOE) recently signed an Action Memorandum approving the removal of the Brookhaven Graphite Research Reactor (BGRR) above-ground ducts as a "time-critical" removal action. "Time-critical" removal actions are approved when there is a need for an immediate response to a known hazard.
The BGRR was an air-cooled reactor. During operation, cooling air was pulled through the reactor pile and sent through a series of filters and coolers within below- and above-ground ducts. Fans then exhausted the air through the familiar red-and-white stack. These fans were removed in the winter of 1999-2000. The below-ground ducts and air filters will be studied in a future sub-project.
The concrete above-ground ducts are part of the BGRR original construction, and are about 225 feet long. The concrete is showing signs of age and weathering; the surface is beginning to crack and flake. Small fist-sized chunks of concrete have fallen from the ducts (the uppermost portion is about 35 feet in the air) to the ground. Moreover, there is evidence of previous rainwater intrusion into the ducts, and the original exterior surface coating contains lead, asbestos, and PCBs.
At this point, the greatest hazards are to workers (due to small chunks of concrete falling) and to the ground (through contact with the old sealant containing lead, asbestos, and PCBs). The area under the ducts is roped off, and the area is inspected weekly, after high winds, and after rainfall. Any materials found are removed from the ground.
When the BGRR decommissioning project was initiated, project planners assumed that the above-ground duct remediation would go through the normal decision-making process. In this process, an Engineering Evaluation/Cost Analysis study is performed before a decision is made among possible courses of action.
During initial characterization of the ducts, however, it was discovered that the ducts were in worse physical condition than was originally thought. The only viable alternatives were to repair the ducts until they could be removed, or to simply take them down now. DOE has agreed that the most prudent action, especially considering worker safety and protection of the environment, is to remove the above-ground ducts now.
Earlier this year, Brookhaven National Laboratory requested bids on this removal, and prospective contractors met with the decommissioning project team to discuss the job. Contract bids were evaluated for their safety procedures and operating techniques, as well as cost. A contract has been approved, and work is scheduled to begin in April 2000.
The Action Memorandum: Brookhaven Graphite Research Reactor Above Grade Ducting Removal Action, the document approving this time-critical removal action, is available in local libraries and on the web at http://www.bgrr.bnl.gov/docs.html.