Hanford's 118-K-1 Solid Waste Burial Ground is located near the K-East and K-West reactor area and was in operation from 1955 until 1971. The waste found in this burial ground came from activities at both reactors, as well as from the N Reactor.
As with the other burial grounds found near the deactivated reactors, 118-K-1 consists of a series of trenches and pits of various sizes. Crews from Washington Closure Hanford are in the midst of cleaning up the site –removing the waste, as well as any soil which may have become contaminated by the waste over the years.
When it comes to remediating burial grounds such as 118-K-1, crews must spend a lot of time planning the cleanup effort so that the work of physically removing the waste can be done so safely. Crews have to review records to determine what kinds of materials and waste were disposed, burial ground boundaries must be pinpointed, plans must be implemented to prepare for any unexpected wastes or hazardous wastes that are uncovered, and most important, crews must understand the steps that have to be taken in order to protect workers during remediation activities.
Once remediation begins, waste is uncovered, sorted, characterized, and surveyed for radioactivity. Any anomalies discovered are set aside for identification. Contaminated soil is also characterized and surveyed. Almost all of the waste removed from burial grounds like 118-K-1 is loaded into trucks and transported to the Environmental Restoration Disposal Facility, Hanford's onsite disposal facility for cleanup wastes, which is regulated by the U.S. Environmental Protection Agency.
Because the waste found in 118-K-1 came from reactor operations, crews have found contaminated materials with high radioactive dose rates. Some of these items include hardware from the reactors themselves. The site contains unlined trenches in which waste was placed, as well as vertical silos (inverted culverts), into which other radioactive materials were placed, including nickel-plated boron balls. The boron balls were part of the reactors' emergency control system, and represented a way to shut down the reactor whenever operators weren't able to use the standard method of inserting control rods or safety rods to stop the nuclear chain reaction.