DOE Sees Reduction of Mercury into Local Creek
WC Monitor
6/27/2014
It looks like the Recovery Act-funded cleanup of the old storm-sewer system at the Y-12 nuclear weapons plant is finally starting to pay off with a reduction of mercury entering the East Fork Poplar Creek in Oak Ridge. “It looks like it’s getting better,” Laura Wilkerson, a manager in DOE’s Oak Ridge Environmental Management Office, said. “But we think it’s going to take even longer to prove that it was a success. The indication is positive.”
The Tennessee Department of Environment and Conservation agreed that it’s too early to declare that the West End Mercury Area (WEMA) project at Y-12 has been a success. Kelly Brockman, a spokeswoman for TDEC, said state officials observed mercury levels in the creek increasing during the effort to reline the storm sewers and later declining after the work was done. However, she said TDEC “has not observed an appreciable change in the level of mercury in the fish in East Fork Poplar Creek.” She added: “At this point, it is too early to assess whether or not the WEMA project has impacted the mercury situation in the creek.”
WEMA was among dozens of Oak Ridge projects funded with hundreds of millions of dollars from the American Recovery and Reinvestment Act of 2009. It also was among the most difficult and ambitious. The project was designed to clean up and repair Y-12’s deteriorated storm-sewer system, parts of which date back to the plant’s World War II origins. The system is a collection point for Y-12’s on-site mercury pollution—the result of large-scale spills during development of hydrogen bombs in the 1950s and ‘60s. The storm sewer also is a conduit for discharges into East Fork Poplar Creek. The creek originates inside the plant’s boundaries and eventually flows through much of Oak Ridge’s west side. While Y-12’s discharges have improved dramatically over the years, the residual amounts of mercury still exceed standards set forth by the Clean Water Act. And the creek remains posted as a health hazard, a status it’s had for more than 30 years.
Wilkerson said the WEMA project had removed about 54 pounds of elemental mercury from the storm system. In addition, she said, workers were able to seal or repair many of the cracks and holes in the concrete that historically allowed mercury contamination in Y-12 buildings and soil to seep into the storm sewers and be flushed into the creek.
Project Challenges
The project encountered a number of problems. Parts of the storm system were inaccessible or had crumbled and couldn’t be repaired. Work was stopped for a month at one point because of safety issues with a subcontractor, Safety and Ecology Corp., and there was a fish kill attributed to the work. Also, the project ended up costing about $17.2 million, a few million dollars more than anticipated.
It wasn’t a surprise that levels of mercury in the creek actually increased while the WEMA work was underway. That’s was expected because the cleanup activities stirred up some of the mercury-contaminated sediments and allowed them to migrate with the stormwaters. Before cleanup of the storm drains began in 2010, the mercury concentration in the water at Station 17 — the sampling point where the East Fork leaves Y-12 property — was about 580 parts per trillion. As the work progressed, the mercury concentrations rose, and when the field work was completed in 2011 the mercury level was at 800 parts per trillion. It later peaked at about 900 parts per trillion, DOE said.
Since then, there’s been a downward trend, and by the end of 2013, the mercury in the creek was about the same as it was before the WEMA project got started, DOE’s Wilkerson said. She said the mercury levels have continued to decline, with some recent samples as low as 200 parts per trillion—a goal of one of the Record of Decision agreements established by DOE, the U.S. Environmental Protection Agency and the Tennessee Department of Environment and Conservation.
Wilkerson said it’s a complex challenge because reducing the mercury in the creek’s water does not necessarily bring about similar reductions in fish and other aquatic life. Jason Darby, a project manager in DOE’s environmental office, said over the years—as conditions in East Fork have changed, including water flow — there have been changes in the fish species and their mercury concentrations. Years ago, the fish species with the highest mercury concentration was the redbreast sunfish, but now the rock bass is at the top of the food chain with the highest concentration of mercury, Darby said. In some cases, the levels of mercury in fish are actually going up, not down, he said.
Additional Projects Planned
A number of projects are underway or planned to reduce mercury in the creek and to start to identify more of the mercury-laden areas of the Y-12 property. The Department of Energy is funding some research activities at Oak Ridge National Laboratory to better understand mercury in the environment. The biggest project on the near-term agenda is a new treatment plant at Y-12 near the point—known as Outfall 200—where mercury from the storm system enters the creek. Design work on the $125 million project is already underway with construction to begin in 2017 and first operations in 2020. The system will reportedly filter up to 3,000 gallons a minute at the head of the creek to remove the mercury before it can pose a downstream hazard.
DOE Deems K-25 Demolition Complete
The biggest D&D project in history has been monitored, milestone by milestone, for the better part of a decade, but the U.S. Department of Energy is finally saying it’s a done deal. Demolition of the K-25 Building in Oak Ridge was completed late last year, but that was not the end of the project. According to DOE, many other tasks had to be accomplished before the project could be officially declared complete, and now the DOE contractor, URS | CH2M Oak Ridge LLC (UCOR), has done those jobs and done them ahead of schedule and under budget. At a June 25 workshop on Oak Ridge cleanup priorities, DOE’s acting cleanup chief at Oak Ridge, Sue Cange announced to the gathering that Wendy Cain — DOE’s EM oversight chief on the project – had completed the walkdown of the site with the cleanup team. “And they have declared completion,” Cange said, with that announcement drawing applause.
In a statement, Cange said: “The project doesn’t end when the final wall comes down. A lot of work had to take place before we could truly consider the project complete. For example, we had to remove and dispose of all demolition debris. That’s a crucial part of completing this project, but much more had to be done to ensure that the site was left stabilized and safe.”
UCOR Honors Small Businesses
URS-CH2M Oak Ridge, DOE’s environmental cleanup manager in Oak Ridge, honored small businesses for their contributions at the annual awards ceremony this week. According to UCOR, 80 percent of its subcontracted work goes to small businesses. That work was valued at $78.2 million this fiscal year.
The categories and small-business winners were: Small Business: PacTec, Inc.; Small Disadvantaged Business: Spectra Tech, Inc.; HUBZone Small Business: Container Technologies Industries, LLC; Woman-Owned Small Business: Value Added Solutions, Inc.; Veteran-Owned Small Business: Technical & Field Engineering, Inc.; Service-Disabled, Veteran-Owned Small Business: Firehawk Products and Services; Customer Service Award: I&I Sling, Inc.; Protégé: Veterans Contracting Solutions Group, LLC.
