FORTY-TWO YEARS OF UNREGULATED OPERATION OF A MAJOR NUCLEAR FACILITY ON A KARST/FRACTURED ROCK - OAK RIDGE TENNESSEE: WHAT COULD POSSIBLY GO WRONG?

The DOE Oak Ridge Reservation (ORR), East Tennessee, home to the Oak Ridge National Laboratory (ORNL), was an integral facility for the WW-II Manhattan Project and subsequently cold war production of radio-isotopes for research and weapons production.

Decades of radionuclide, inorganic, and organic waste from legacy DOE operations on the ORR, were disposed of by shallow land burial and “deep” well injections (>300m). Waste was also inadvertently “lost” via additional leaks and spills. Liquid wastes were also retained for radiological decay in unlined surface impoundments in Bethel Valley before being discharged to White Oak Creek or disposal in unlined trenches or pits in Melton Valley. Quantities and concentrations of waste could be considered “high.” For example, in groundwater at ORNL, 90Sr concentrations are reported at > 1,000,000 pCi/L, VOA concentrations >10,000 ppb, mostly TCE and DCE, and high activity of other radionuclides - 233U. Even so, after >60 years and several billion dollars spent, waste areas are essentially incompletely characterized or have almost none. Characterization of groundwater contamination is mostly in the shallow bedrock near the source of release and except for Melton Valley is virtually non-existent.

The use of sodium hydroxide was ubiquitous in both Melton and Bethel valleys for corrosion protection and fixation of radionuclides. Waste was disposed of on Cambrian and Ordovician fractured clastics and carbonates. Consequently groundwater pH values on and immediately offsite have been measured between 9 - 12.9, VOAs and radionuclides have also been reported in offsite residential wells. Aliasing of the sampling is virtually certain and the true picture is probably worse than is apparent.

Recent sampling of offsite DOE monitoring wells in Melton Valley, across the Clinch River (DOE claims the river to be a hydrologic boundary) has been done with interesting field parameters. Field pH values sometimes approach 13 (12.92), and compare to pH values measured in nearby residential wells (8.5 - 10.75). Residential offsite wells across the river in Bethel Valley have strange waters, atypical of carbonate waters and have shown ph above 9, 99Tc, gross alpha, (102 pCi/L) beta and VOAs. One deep well has 50 VOAs including exotic organics, many likely to have been used at a major nuclear facility.