The Gerstle River Test Site (GRTS), approximately 19,000 acres, has been a part of Army operations since it was acquired under Public Land Order 910 on August 7, 1953.

Testing activities were performed at GRTS since the mid-l 950s. Complete records describing test activities between 1954 and 1962 are not available; however, limited information indicates that the Army performed some surveillance, chemical agent munitions and high-explosive munitions testing during this period. During later testing in the mid 1960s the Army could not account for the detonation of one high explosive round. As a result of the test activity on these areas, numerous cleanup operations have occurred from 1968 to 1971. These operations were conducted to clear the areas of chemical and explosive contamination.

Blueberry Lake, a man-made lake in an area of the Test Site, was used while frozen over to store materiel pending disposal. An incident occurred in the spring of 1967 (date varies in sources reviewed). Munitions containing the nerve agent GB (total unknown), a cylinder of the nerve agent GA, a cylinder of GB and vials from agent test kits containing GB, VX (a nerve agent), HD (distilled mustard) and lewisite were stored on the ice-covered lake pending disposal. In the spring when the ice melted, these items sank to the bottom of the lake. The lake was drained and the items were recovered during a subsequent clearance operation. The recovered materiel was decontaminated, detonated, and buried in pits located at the lake.

A second cleanup operation occurred as a result of reports of 55-gallon drums of HD that were buried near a command post on the Test Site land. During the investigation two additional burial pits were located. The first pit contained HD residue from testing and three empty, burned, ton containers of mustard. The second contained no contaminated materiel. This materiel was transported to the burial pits at Blueberry Lake.

Later, all debris from test grids and leased land was removed and transported to disposal pits at the Test Site. Debris clearance from the two main burial pits at Blueberry Lake was completed.

CWM munitions (GB, GA) and nerve agents (VX, GB) as well as Mustard and Lewisite.

A 1987 site investigation included multi-media environmental sampling for selected parameters, including explosive-type compounds and the breakdown/degradation products expected from chemical agents.