Rocky Flats dam removal dredges up contamination concerns, Boulder Weekly ,By Josh Schlossberg -June 29, 2017, The City of Broomfield and the Woman Creek Reservoir Authority (WCRA), a political subdivision and public corporation of the State of Colorado, are opposed to a U.S. Department of Energy (DOE) plan to breach a dam on a pond collecting surface water flowing from Rocky Flats, the former nuclear weapons facility site 10 miles south of Boulder.
DOE has contended that the dam on Pond C-2 is “no longer necessary to site operations” and wants to remove it sometime between 2018-2020 to return surface water flow to Woman Creek, thereby enhancing streamside wildlife habitat and encouraging wetlands. Removal would cause “no significant impact,” as determined by an environmental assessment conducted under the National Environmental Policy Act (NEPA).
Getting rid of the dam would also cut DOE costs related to inspection, reporting and upkeep, which WCRA estimates to be around $17,000 per year.
Yet according to a 2016 document prepared for WCRA by Boulder-based Hydros Consulting Inc., removal of the dam would “represent an irreversible loss of an effective contingency to protect downstream water quality” in Standley Lake, the drinking water supply for Westminster, Northglenn and Thornton, also used for irrigation, fishing, boating and water skiing.
Alan King, director of public works for the City and County of Broomfield, wrote in his June 2010 correspondence with DOE that the breach would “clearly increase the potential for uncontrolled releases of contaminated surface water off-site that would negatively impact downstream watersheds and expose downstream communities to additional risks.”
Pond C-2 is located on the border of the former Rocky Flats facility site 1.25 miles upstream of the Woman Creek Reservoir, the latter of which was built in 1996 to capture Rocky Flats runoff and keep it from reaching Standley Lake. The pond is currently operated in “batch-and-release mode,” where it is allowed to fill to roughly half capacity, and then discharged up to two times per year, according to DOE’s Environmental Assessment.
“Significant [plutonium] and [americium] contamination remains in surface soils on the DOE-retained land in the Woman Creek drainage, particularly on the 903Pad Hillside, with [radioactive] mass loading to Pond C-2 comparable to pre-closure conditions,” Hydros Consulting documented.
The 903Pad is an area of Rocky Flats where more than 5,000 buried barrels of liquid radioactive waste leaked, contaminating an estimated 261,000 square feet of soil before they were removed, according to the Colorado Department of Public Health and Environment (CDPHE).
GS51 is a surface water sampling location within the former facility site just south of the 903Pad and upstream of a ditch which DOE says flows “quite infrequently” into Pond C-2. On October 4, 2013, a month after the flood of 2013, GS51 “recorded elevated levels of plutonium in excess of the applicable standard,” according to a September 2015 memo from the Town of Superior Trustees to the Rocky Flats Stewardship Council.
King noted that Pond C-2 also receives runoff from several other areas that have “residual contamination.”
“Elevated readings for uranium have been recorded in this pond, and DOE-LM acknowledges that it is not 100 percent natural uranium,” wrote King.
On April 4, 2016, water samples collected on Woman Creek reached 0.313pCi/L (picocuries per liter) for plutonium and 0.17pCi/L for americium, “the first sample over 0.15pCi/L in more than 20 years of sampling…” according to Hydros Consulting.
Surface water samples “indicate that solids transported in runoff … have, at times, been above the Site closure cleanup target for surface soils” of 50pCi/g (picocuries per gram), occurring “in four out of five of the most recent years,” mostly attributed to plutonium.
Playing with fire
Typical events aside, the City of Broomfield and WCRA fear that a wildfire or landslide in contaminated areas within Rocky Flats may result in further downstream contamination…….http://www.boulderweekly.com/news/breach-of-trust/
