DOE outlines priorities for cleanup

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Projects include remediation of chromium plume under Mortandad Canyon, dealing with 60 barrels involved in WIPP accident, cleanup of two legacy sites on southside of Los Alamos Canyon

By Tris DeRoma

The Department of Energy’s Los Alamos Environmental Management Field Office outlined its immediate priorities for safety and cleanup this week at the Los Alamos National Laboratory.
Those projects included the remediation of a chromium plume under Mortandad Canyon, and dealing with the 60 barrels of toxic waste and nitrate salts involved in the Waste Isolation Pilot Plant accident in 2014.
“The Environmental Management Los Alamos Field Office’s biggest priorities right now are the safety of the workers and the public as we execute our mission,” said Steven Horak, the field office spokesman said in a written statement Thursday.
Lab to start treatment of barrels this spring
The 60 barrels of transuranic waste are stored at Area G in an air conditioned and filtered facility that’s kept at a constant 57 degrees Fahrenheit.
Lab workers have also installed a special filter and venting systems on the barrels’ lids as further prevention against the type of accident that happened at the Waste Isolation Pilot Plant in Carlsbad in February 2014.
The 60 barrels were ready to be shipped to WIPP when the accident occurred.
A barrel of transuranic waste being stored 2,000 feet underground at WIPP burst, leaking radioactive waste into WIPP’s storage areas and ventilation systems. The leak was attributed to a heated, chemical reaction that took place inside the barrel, caused by the wrong type of kitty litter mixed into the waste. The litter was supposed to act as neutralizer. The barrel was shipped from LANL.
The accident caused a shutdown of the plant for the next three years as workers cleaned up the mess to make the facility safe for normal operations.
Meanwhile, LANL has held the remaining 60 barrels suspected of containing the same type of kitty litter and immediately took steps to fix the problem through the installation of the special valve and vent system and placing the barrels in a cold storage.
This spring, contractors for EM Los Alamos will be taking those barrels four miles down the road to another facility where they will be opened and remixed with zeolite, a type of mineral that will further neutralize the type of waste being stored in the barrels so no more chemical reactions like the one that caused the accident at WIPP will occur.
Each barrel will take a day to process, officials said. Each barrel will be individually loaded into a special container, called a “glove box” where workers, who have been training for the task, will unseal the barrel, take one and one-third quarts of waste, mix it for three minutes with a gallon of zeolite and 2/3 quarts of water and put the new mixture into a new barrel.
From the 60 barrels, the process is expected to generate 250 to 300 new barrels of waste, waste that will be able to be stored safely at WIPP when eventually shipped. Shipping the newly packed waste could take place as early as fall, though no official date has been given.
Lab to experiment with chromium remediation
Starting this summer, EM contractors will experiment with an attempt to stop the spread of a decades-old chromium plume with molasses. The spill is located under Mortandad Canyon in a regional aquifer in an area where LANL borders San Ildefonso Pueblo. The spill dates between the 1950s and early 1970s, when chromium was regularly flushed from a power plant into Sandia Canyon.
The chromium migrated downstream into the aquifer under Mortandad Canyon. In 2005, LANL established monitoring wells to determine the length and width of the plume, which has already found the aquifer under Sandia and Mortandad Canyon and is slowly spreading toward the border with San Ildefonso Pueblo. Since 2005, LANL also installed several injection and extraction wells over the plume to slow down the spread. The wells draw the chromium-laced water out of the ground and redeposit the cleansed water back into the aquifer.
This summer, contractors for EM will run an experiment where they will inject a mixture of molasses into one of the injection wells. It’s hoped that microbes feeding on the chromium will also consume the molasses and multiply, speeding up the breakdown of the chromium into a more harmless form of chromium. If the experiment is successful, then that may be the technique LANL uses to halt and clean the chromium spread, with no further remediation needed.
Progress at Los Alamos, Pueblo Canyons
LANL has also made progress cleaning up Los Alamos Canyon. In its Tuesday briefing, officials said they are concentrating on cleaning up two areas of waste off the south side of the canyon.
The spots aren’t big. The largest, located off the side of a cliff into the canyon in the 2000 block of Trinity Drive, is about 20 feet by 35 feet. Nearly all of the cleanup in the Los Alamos and Pueblo Canyon is leftover waste from the Manhattan Project and early stages of the Cold War.
Types of waste found at the sites include various metals, solvents and radionuclides. Cleanup is done with special excavators designed for steep slopes and digging soil out of the sides of cliffs. The excavated soil is loaded onto trucks and shipped to LANL’s Tech Area 21, which is used as a staging area for later shipment to waste treatment sites throughout the country.
The cleanup of the two sites are expected to be cleaned by the fall.
Three remaining sites are scheduled to be cleaned at a later date.