HANFORD — The Department of Energy has checked 115 square miles of Hanford off its environmental cleanup list.
The agency announced Monday that cleanup had been completed on all of the Arid Lands Ecology Reserve, including Rattlesnake Mountain, with the exception of a Nike missile bunker there. Gone are Cold War Army buildings, most communication towers and much of the remnants left from decades of research.
"The completion of demolition and debris cleanup on (the reserve) is a major milestone in reducing the Hanford Site cleanup footprint," said Matt McCormick, manager of DOE's Hanford Richland Operations Office, in a statement.
DOE has set a goal of shrinking the area of Hanford needing environmental cleanup from 586 square miles to 75 square miles at its center by 2015. Much of the $1.96 billion the Hanford nuclear reservation received in federal economic stimulus money is being used toward that goal.
The Arid Lands Ecology Reserve, or ALE, is part of the security buffer zone around the production portion of Hanford where plutonium was produced for the nation's nuclear weapons program during World War II and the Cold War. For the last decade, it's been part of the Hanford Reach National Monument, owned by DOE but managed by U.S. Fish and Wildlife.
Rather than tearing down buildings and digging up burial grounds contaminated with radiation and hazardous chemicals from nuclear production work, the environmental cleanup in the Rattlesnake Mountain area is more conventional.
Doug Shoop, deputy manager of the DOE Hanford Richland Operations Office, described the work as it began as including "a whole lot of little things. It's not radiological but it should be cleaned up."
Contractor CH2M Hill Plateau Remediation Co. took down 24 buildings and additional communication towers and cleaned up 362 debris sites, ranging from makeshift pens for elk research to wrecked cars. It had $4 million in economic recovery money for the work.
ALE has been closed to the public since 1943, but before that had some ranches and the first producing natural gas field in Washington, which was abandoned in 1941 when gas reserves dried up.
In the 1950s, the Army put a Nike Missile bunker on ALE near the base of Rattlesnake Mountain and established an Army camp nearby. It included barracks, a mess hall, administration building and latrine.
The camp has been torn down, but ALE's Nike missile bunker will remain until at least summer as a laboratory for the study of gravity.
The bunker includes two identical magazines with a 22-yard-long tunnel connecting them. Between 1955 and 1960 the bunker housed 20 of the 35-foot-long Nike Ajax missiles and staff to protect Hanford from an aerial attack.
It was decommissioned in 1961 but was later designated as an emergency relocation center in a nuclear attack or accident for high-level Hanford personnel and community leaders.
One side of the bunker looks much as it did in the 1960s. But the other side was converted into the Battelle Gravitational Physics Laboratory at the request of researchers.
The underground bunker originally was part of the current cleanup project, but after months of uncertainty for the researchers, DOE agreed to allow them to complete gravitational expheriments paid for by the National Science Foundation. About $7 million has been spent on the work to date.
Scientists at the University of Washington and the University of California at Irvine picked the underground bunker for their experiments because they needed absolute stillness. Their instrumentation is so sensitive that they can collect data only from early April to late October, when the instruments don't pick up vibrations from winter storm-driven ocean waves in the north Pacific Ocean.
But the bunker has been anything but quiet as cars and trucks rumbled along the surface of the ground overhead just 80 feet away to the nearby staging area for cleanup.
Because of the disruption, scientists have been given extra time to finish their research. Work has resumed and is expected to be completed this summer and then DOE will make arrangements to remove the bunker as money becomes available.
In addition to taking down the lower ALE military camp, Army buildings at the top of Rattlesnake Mountain also have come down, including a large administration and barracks building later used as a space science laboratory.
Since 1964, DOE also had leased property on the top of Rattlesnake Mountain to public and private agencies for emergency and commercial communication. The buildings that supported that activity have been demolished along with all but one communication tower.
It remains as part of a new consolidated communication center that takes up less space. The area is considered sacred by tribes and has a delicate ecosystem that researchers and U.S. Fish and Wildlife want to protect.
The Rattlesnake Mountain Observatory has been removed from the mountain top, but the Alliance for Advancement of Science Through Astronomy is preparing to reassemble it when a new site in the Mid-Columbia is picked.
Also gone is a laboratory at Rattlesnake Springs for ecological and environmental research projects on radionuclide contamination of plants and animals.
However, other buildings besides the combined communication center will remain.
U.S. Fish and Wildlife will continue to use six buildings, including a maintenance garage and machine shop. Most of the buildings that have been torn down had water damage, mold and pest infiltration.
In addition, a concrete structure used in the early natural gas project remains, but its two concrete cisterns have been filled with rock after an elk fell in one and had to be rescued.
ALE will continue to be used long-term for ecology and other research, and some equipment and structures remain, such as meteorological towers and seismic stations.