The model results presented in this report incorporates the reported data through June 2004 and then uses the updated discharge and tritium inventory values through 2034 based on more current information . Simulation results show that the tritium concentration in the aquifer reaching1.6 million pCi/L in 1996 After that time, predicted concentration levels at the water table were variable ranging from just over 1 million to several hundred thousand pCi/l and on a downward trend by the year 2004, These simulated results generally reflect the changes in simulated monthly effluent discharges and tritium inventories discharged to the aquifer in the model analysis. These results are also generally consistent with tritium concentration levels and trends that have been observed in well 699-48-77A, the well south of the SALDS facility that is the first well impacted by SALDS operations. Given the differences between the smaller actual facility discharges and those projected in previous modeling, the updated 2004 model was generally consistent with previous estimates made with the 1997 model with regard to plume behavior. Concentrations for the updated model did not reach levels projected in 1997 and the plume did not extend as far out as was estimated in previous modeling. However because of the increase in tritium inventory in the updated projections from effluents originating from the Waste Treatment Plant, estimated tritium concentration levels beyond the year 2004 were projected to be much larger and to remain longer in the aquifer than was estimated in previous modeling efforts.
Revised: October 7, 2004 |
Published: October 4, 2004