UCOR Looks to Other Oak Ridge Cleanup Work as K-27 Demo Accelerates

URS-CH2M Oak Ridge (UCOR), the Department of Energy’s cleanup manager in Oak Ridge, continues to accelerate the demolition of the K-27 uranium-enrichment facility – the last of the five gaseous diffusion plants at the site now known as the East Tennessee Technology Park – and the progress is allowing the contractor to push ahead with preparations for other cleanup projects that will follow once the K-27 tear-down is complete.

It appears K-27 demolition will be completed well ahead of the end-of-2016 target date.

Next up on the cleanup agenda will be the demolition of a series of other buildings near K-27 – known collectively as the Poplar Creek Facilities — that contributed to the uranium-enrichment complex that was the nation’s largest producer for the first half of the Cold War.

The Poplar Creek Facilities and related structures are “extensively deteriorated,” UCOR spokeswoman Anne Smith said in response to questions.

“Deactivation to prepare the buildings for demolition is in progress,” she said this week. The schedule for demolishing and cleaning up the Poplar Creek Facilities has not yet been released.

The Poplar Creek Facilities are located north and west of K-27 and were originally build to support activities at K-27 and the former K-29 plant, which has already been demolished and remediated.

There are a total of 10 “significant facilities,” Smith said, including two “process gas” (uranium hexafluoride) facilities, as well as multiple process gas/utility tie-lines, and various other buildings, support trailers, and structures on the site that are considered to be part of the contractor’s Poplar Creek work scope.

Here’s are some of the main Poplar Creek Facilities:

K-131: Built in 1945 to purify the uranium-hexafluoride feed to K-27. The building has five floors, including a basement and “penthouse.” The K-131 purification process was relocated to another facility in 1954, according to UCOR. The building was operated as a feed facility from 1948-1955 and repurposed in 1956 as a maintenance and valve repair shop. It was shut down in 1985.

K-631: This two-story building — in the shape of a cross — was constructed in 1945 and operated until 1962 as a “tails” withdrawal facility, extracting process gas depleted of fissionable uranium isotopes. K-631 was converted to a fluorine treatment facility in 1970, and it was closed in 1985. Building K-631 houses process equipment and associated piping that resulted in contamination of floors and equipment. The building, which shares one wall with K-131 and is connected to the other facility by doors, is posted as a “radiological high contamination area.”

K-633: This building was constructed in 1954 and includes two main high bays and several “attached” rooms. This steel-framed, asbestos cement-paneled facility was used as a test facility for process gas equipment. It houses four “independent test loops” of various sizes and types for gaseous diffusion processes. K-633 was shut down in 1985, the same time the Oak Ridge Gaseous Diffusion Plant was placed in cold standby.

K-1232: The two-story, steel-frame building and its auxiliary support facilities were built in 1976 and used for chemical recovery operations for non-fissile materials until about 1983, according to UCOR. It was then modified for the use in neutralization and treatment of waste products from Y-12. The facility was shut down shortly thereafter. “There are large metal roll-up doors at the east and west ends, such that tanker trucks of waste could enter the facility to be sluiced, cleaned and the chemicals they contained processed,” UCOR said in information provided via email. “This drive-through facility with process tanks along one side and process equipment along the other, were used occasionally until mid-1991.”

K-832: This building was used as a re-circulating water pump house. It has a concrete frame and concrete exterior walls, as well as a substructure with two concrete channels about 30 feet wide and 20 feet deep. It was shut down in 1985.

K-832-H-Cooling Tower: This structure began operation in 1945 to support the K-29 systems, but the original 14-cell tower was replaced in 1985 by a five-cell tower, UCOR stated. The old cells were demolished when the new ones were constructed. “In 1985, the tower was shut down after a very short period of operation when the uranium enrichment facilities ceased operations,” UCOR said.

K-1203: This building housed the plant’s sanitary sewage treatment. It consisted of a biological treatment plant, lift stations, sedimentation basins, filtration and processing of sludges, according to information provided by the cleanup contractor. This facility was closed on May 29, 2008.

K1314-G, H and J: These facilities were used for refurbishment of UF6 storage cylinders. The complex consists of three 40 foot-by-80 foot metal buildings with HEPA ventilation systems attached. The three buildings “contained the sand blasting and painting processes used to refurbish the UF6 cylinders prior to the cylinders being transported to other DOE facilities,” UCOR said. “These facilities were last used 2002.”