Rulison

Project Rulison
View of Rulison Site.
Information
Country	United States
Test series	Operation Mandrel Operation Plowshare
Test site	near Parachute, Colorado
Date	September 10, 1969
Test type	Underground
Yield	40 kt

Project Rulison, named after the rural community of Rulison, Colorado, was an underground 40-kiloton nuclear test project in the United States on September 10, 1969, about 13 kilometres (8 mi) SE of the town of Grand Valley, Colorado (now named Parachute, Colorado) in Garfield County. The location of "Surface Ground Zero" is 39°24′19.0″N 107°56′54.7″W / 39.405278°N 107.948528°W / 39.405278; -107.948528. The depth of the test cavity was approximately 8,400 feet below the ground surface. It was part of the Operation Mandrel weapons test series under the name Mandrel Rulison, as well as the Operation Plowshare project which explored peaceful engineering uses of nuclear explosions. The peaceful aim of Project Rulison was to determine if natural gas could be easily liberated from underground regions. This site remains under active monitoring by the U.S. Department of Energy Office of Legacy Management.

The test succeeded in liberating large quantities of natural gas; however the resulting radioactivity left the gas contaminated and unsuitable for applications such as cooking and heating homes. Although projected public radiation exposures from commercial use of stimulated gas had been reduced to less than 1% of background, it became clear in the early 1970s that public acceptance within the U.S. of any product containing radioactivity, no matter how minimal, was difficult if not impossible. The Department of Energy began a cleanup of the site in the 1970s which was completed in 1998. A buffer zone put in place by the state of Colorado still exists around the site. A January 2005 report by the DOE stated that radioactivity levels were normal at the surface and in groundwater, though a later report due in 2007 was expected to more fully explore if there was subsurface contamination and whether or not radioactivity was still spreading outward from the blast site itself.