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A small island 44 miles long by 5 miles wide that sits as part of the Rat Island Group, the most southerly islands of the Aleutian chain. It lies about 1340 miles southwest of Anchorage, Alaska and 870 miles east of Petropavlovsk, Kamchatka in the Russian Far East. During World War II it provided a strategic fighter bomber airbase defense against Japanese invasion. At one point it numbered 15,000 troops and was instrumental in reclaiming the U.S. territory of Kiska and Attu Islands that were captured and occupied by Japan. The first nuclear test conducted on Amchitka was Long Shot. An Atomic Bomb detonated 2300 feet underground on October 29, 1965. Its purpose was to investigate Americas ability to detect nuclear explosions from the Russian far east and distinguish them from naturally occurring earthquakes. It's yield was approx. 80 kilotons or 5.3 times that of Hiroshima. The second nuclear test was Milrow. A Hydrogen bomb
exploded at a depth of 3992 feet below the surface on October 2, 1969. Its yield was 1
megaton, about 67 times that of Hiroshima. Basically it was a calibration
test needed to determine the effects on the biosphere, landslides,
water wave production (tsunamis), aftershocks and other seismic -related
effects. It was also used to determine if the Island would be
able to withstand an even larger explosion. The third and last nuclear explosion was Cannikin. Detonated inside a 52 foot diameter cavity at the bottom of a 5,875 foot shaft on November 6, 1971. It's yield was 5 megatons or 385 times that of Hiroshima. It is today the largest underground nuclear explosion conducted by the United States. The 730 underground nuclear tests conducted by the U.S. produced a total yield of 37 megatons, and Cannikin's yield alone represents 14 percent of the total. It was a test of the Warhead of the Spartan anti-ballistic missile system (ABM). It reputedly fractured the earths crust. The seismic shock from the explosion registered 7.0 on the Richter Scale. 38 hours after the explosion a 1 1/2 mile wide by 60 foot deep subsidence crater formed as the volume of material above the cavity (the chimney) collapsed into the void. In the early 1980s it was determined that environmental damage to Amchitka Island by the nuclear tests and prior U.S. Government occupations needed to be investigated, assessed, and a cleanup plan implemented. It was placed on the Environmental Protection Agency Superfund list as an uncontrolled hazardous waste site, which opened the door to the money required for the cleanup operation. The U.S. Department of Energy (DOE)developed the plan of attack with engineering contractor IT Corporation out of Las Vegas. In May of 2001 a base camp was set up to house the cleanup workers. There was a combination of crews, representing the U.S. Department of Energy, the U.S. Navy, the U.S. Corps of Engineers, and the U.S. Fish and Wildlife service. A civilian contractor, Brice Environmental Services Corporation of Fairbanks, Alaska, subcontracted the surveying portion of the contract to our company, McClintock Land Associates of Eagle River, Alaska. Bill McClintock assigned me and Tom Pickett, a land surveyor based out of Georgia, to spend the summer on Amchitka performing the surveys for the remediation sites. There we were to join another surveyor, Gerald (Gerry) Kurtz, who was employed directly by Brice Corporation. A total of eight sites on Amchitka needed extensive surveying to determine the volumes of contaminated water and mud that needed to be stabilized. Also needed was slope staking and grading of the contaminated sites to DOE specifications and other surveying as requested by the contractor Brice.
Once the class was completed we loaded into a government chartered Learjet for the ride out to the Island. Our surveying equipment and truck having already been compiled and shipped via barge two weeks prior. Cargo space was very limited on the Lear jet and we were allowed only one small bag each, But was also able to take a few basic surveying essentials like a Topcon GTS-800 Robotic Instrument and tripod just so we could hit the ground running if the barge had not arrived. We landed 3 1/2 hours later on Amchitka in a 40 mile per hour crosswind with horizontal rain which we found was pretty much the normal weather pattern. We then attended an orientation meeting to discuss safety issues and point out restricted areas that contained untold amounts of unexploded bombs and shells. We found that the barge indeed had yet to arrive with our equipment due to sea conditions but with access to two quad runners we were able to recon the cleanup sites and set primary control. The constant rain, wind, and fog made the surveying a challenge to say the least. When the shafts were drilled for the nuclear bombs a mixture of diesel and bentonite were poured down them to produce a highly slippery condition that helped extract the rock and debris. Large holes were excavated near the shafts and this drilling fluid was pumped into them. Water had since filled and covered the bentonite mud creating large toxic ponds. Especially in the ponds of the "Long Shot" explosion where levels of radioactive Tritium have been measured. The first phase of our surveying was to do a topographic survey of the original lay of the ponds and surrounding areas. With the Topcon Robotic instrument set up at a strategic high point we pulled on chest waders and walked into the water to obtain shots on top of the mud surface and then forced our rod down under the mud until it hit hard ground and took shots at the bottom so we could calculate the exact quantity of mud that needed to be stabilized. Shots at the ponds perimeter gave us the necessary shots as to calculate the volume of contaminated water. With these figures we were able to know how many tanker loads would be required to remove the contaminated water. This toxic water was sent to a water treatment facility that was also barged in from the mainland. We calculated How much soil and sand would be needed to be imported and mixed with the bentonite mud to help produce a stable surface. A typical ratio being 1 part mud to 3 parts sand/soil. The second phase of the cleanup operation was to cover the mud mixture with another layer of sand and soil. Another topo survey was then required to make sure the specific depth was met. The third phase was for the contractor to place a geosynthetic liner over the entire mixture capping the pit and isolating it from the environment. Additional Soil was placed over this liner and this was then graded and slope staked so rain would run off and away from the center. Finally, a layer of topsoil was added on top of the entire area and seeded with a mat of native plant seed mixture.
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