4 research outputs found
Innovative Direct Push Technologies for Characterization of the 216-Z-9 Trench at DOE's Hanford Site -8235
ABSTRACT Because of the significant radiological and chemical hazards present at the 216-Z-9 Trench at the US Department of Energy Hanford Site, the only practical subsurface characterization methods are those that minimize or control airborne vapors and particles. This study evaluates and compares the performance of two Direct Push Technologies (Hydraulic Hammer Rig (HHR) and Cone Penetrometer Testing (CPT)) with traditional cable tool drilling in similar difficult geologic conditions. The performance was based on the depth of penetration, the ability to collect representative vadose zone soil samples, the penetration rate, and the relative cost. The HHR achieved deeper penetration depths and faster penetration rates than CPT techniques, while still maintaining the waste minimization benefits of direct push technologies. Although cable tool drilling achieved the deepest penetration, the safety and disposal concerns due to the soil cuttings that were generated made this drilling approach both slow and costly compared to the direct push techniques
Treatability Test for Removing Technetium-99 from 200-ZP-1 Groundwater, Hanford Site -8038
ABSTRACT The 200-ZP-1 Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-1 OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg /m 3 (2000 µg/L) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance of an air-stripping tower. Ten extraction wells and three injection wells operate at a combined rate of approximately 0.017m 3 /s (17.03 L/s). In 2005, groundwater from two of the extraction wells (299-W15-765 and 299-W15-44) began to show concentrations greater than twice the maximum contaminant level (MCL) of Tc-99 (33,309 beq/m 3 or 900 pCi/L). The Tc-99 groundwater concentrations from all ten of the extraction wells when mixed were more than one-half of the MCL and were slowly increasing. If concentrations continued to rise and the water remained untreated for Tc-99, there was concern that the water re-injected into the aquifer could exceed the MCL standard. Multiple treatment technologies were reviewed for selectively removing Tc-99 from the groundwater. Of the treatment technologies, only ion exchange was determined to be highly selective, commercially available, and relatively low in cost. Through research funded by the U.S. Department of Energy, the ion-exchange resin Purolite ® A-530E 1 was found to successfully removeTc-99 from groundwater, even in the presence of competing anions. For this and other reasons, Purolite ® A-530E ion exchange resin was selected for treatability testing. The treatability test required installing resin columns on the discharge lines from extraction wells 299-W15-765 and 299-W15-44. Preliminary test results have concluded that the Purolite ® A-530E 1 resin is effective at removing Tc-99 from groundwater to below detection limits even in the presence of competing anions (e.g., nitrate and sulfate) at concentrations five to six magnitudes higher than Tc-99
Groundwater Pump and Treat Remediation System Overview, Hanford 200-West Area -11508
ABSTRACT The Hanford Site 200-West Area Pump and Treat Facility (Treatment Facility) will be designed, installed, and operated to capture and treat contaminated groundwater to reduce the mass of carbon tetrachloride, total chromium, nitrate, trichloroethylene, uranium, and technetium-99. The Treatment Facility will treat groundwater from as many as 20 new extraction wells with a total average operating flow of 2,000 gal/min (2,500 gpm maximum flow). The treated water will be injected to the aquifer. The Treatment Facility will consist of an ion exchange system, anoxic/anaerobic bioreactor(s), aeration/membrane tanks, and air stripper systems
SGW-35753-FP Revision 0 Treatability Test for Removing Technetium-99 from 200-ZP-1 Groundwater, Hanford Site FLUOR" Approved for Public Release; Further Dissemination UnlL'TIited Treatability Test for Removing Technetium-99 from 200-ZP-1 Groundwater, Hanf
ABSTRACT The 200-ZP-I Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-I OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg 1m 3 (2000 IlgIL) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance of an air-stripping tower. Ten extraction wells and three injection wells operate at a combined rate of approximately 0.017m 3/s (17.03 Lis). In 2005, groundwater from two of the extraction wells (299-WI5-765 and 299-WI5-44) began to show concentrations greater than twice the maximum contaminant level (MCL) ofTc-99 (33,309 beq/nr' or 900 pCi/L). The Tc-99 groundwater concentrations from all ten of the extraction wells when mixed were more than one-half of the MCL and were slowly increasing. If concentrations continued to rise and the water remained untreated for Tc-99, there was concern that the water re-injected into the aquifer could exceed the MCL standard. Multiple treatment technologies were reviewed for selectively removing Tc-99 from the groundwater. Of the treatment technologies, only ion exchange was determined to be highly selective, commercially available, and relatively low in cost. Through research funded by the U.S. Department of Energy, the ion-exchange resin Purolite® A-530E 1 was found to successfully removeTc-99 from groundwater, even in the presence of competing anions. For this and other reasons, Purolite® A-530E ion exchange resin was selected for treatability testing. The treatability test required installing resin columns on the discharge lines from extraction wells 299-W15-765 and 299-WI 5-44. Preliminary test results have concluded that the Purolite" A-530E' resin is effective at removing Tc-99 from groundwater to below detection limits even in the presence of competing anions (e.g., nitrate and sulfate) at concentrations five to six magnitudes higher than Tc-99. 'PuroHte"' A-530E is a registered trademark of the Purolite Company