Download or read book Results of Groundwater Modeling for Tritium Tracking at the Hanford Site 200 Area State Approved Land Disposal Site 2004 written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 reaching 1.6 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.

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State approved Land Disposal Site Fiscal Year 2004 written by Robert F. Raidl and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State Approved Land Disposal Site Fiscal Year 2000 written by and published by . This book was released on 2000 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hanford Site 200 Area Effluent Treatment Facility (ETF) processes contaminated liquids derived from Hanford Site facilities. Groundwater monitoring for tritium and other constituents is required by the state-issued permit at 22 wells surrounding the facility. Water level measurements in nearby wells indicate that a small hydraulic mound exists around the SALDS facility as a result of discharges. Evaluation of this condition indicates that the network is currently adequate for tracking potential effects of the SALDS on the groundwater. During FY 2000, average tritium activities in most wells declined from average activities in 1999. The exception was deep well 699-48-77C, where tritium results were at an all-time high (710,000 pCi/L) as a result of the delayed penetration of effluent deeper into the aquifer. Of the 12 constituents with permit enforcement limits, which are monitored in SALDS proximal wells, all were within groundwater limitations during FY 2000. Analyses for conductivity, total dissolved solids, sulfate, chloride, sulfate, dissolved calcium, and dissolved sodium indicate that well 699-48-77A and, to a lesser extent, well 699-48-77D show the effects of dilute effluent entering groundwater, resulting in a depression of concentrations of these constituents below natural background levels. Recommendations for future monitoring include temporarily increasing the frequency of tritium sampling at wells 299-W7-3, 299-W7-5, and 299-W7-7 to quarterly. This measure may assist in a more accurate determination of the southern bounds of the SALDS-generated tritium plume, provide estimates of travel time for model comparisons, and help preserve the distinction between this plume and the older 200 West tritium plume further east.

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State Approved Land Disposal SiteFiscal Year 2003 written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hanford Site 200 Area Effluent Treatment Facility (ETF) processes contaminated aqueous wastes derived from Hanford Site facilities. The treated wastewater occasionally contains tritium, which is not removed by the ETF, and is discharged to the 200 Area State-Approved Land Disposal Site (SALDS). During fiscal year (FY) 2003 to date (through August 31, 2003), approximately 96-million liters (25.3-million gallons) of water have been discharged to the SALDS. Groundwater monitoring for tritium and other constituents, and water-level measurements are required by the state-issued permit at the SALDS. The current network consists of 3 proximal monitoring wells and 16 tritium-tracking wells. Proximal wells were sampled in October 2002, and January, February, April, and September of 2003. Tritium-tracking wells were sampled in January and September of 2003, but September results were delayed because of fire hazards near the wellheads. Water-level measurements in three wells nearest the SALDS indicate the continuation of a small hydraulic mound beneath the SALDS facility as a result of discharges. This feature is directing groundwater flow radially outward a short distance before the regional northeasterly flow predominates. This condition also places several wells south of the SALDS hydraulically downgradient of the facility. Some of the wells south of the SALDS in the tritium-tracking network have dried or are projected to soon be dry. Wells 299-W7-6 went dry during FY 2003, preventing collection of the September sample from this well. Tritium activities decreased in all three SALDS proximal wells during FY 2003, compared with FY 2002. Timing between detections of tritium and other constituents in well 699-48-77C suggest a delay of approximately 3 years from detection in wells 699-48-77A and 699-48-77D. Sporadic detections in well 299-W7-5 suggest that tritium from SALDS may be reaching the northern edge of the 200 West Area, south of the facility and may be at the extreme southern edge of the plume. Comparison of head distribution in March 2003 and reported FY 2003 tritium activities, with numerical predictions of these quantities for 2000 and 2005, suggests that modeling performed in 1997 only slightly overestimated the areal spread of tritium around the SALDS to date.

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State Approved Land Disposal Site Fiscal Year 2001 written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hanford Site 200 Area Effluent Treatment Facility (ETF) processes contaminated liquids derived from Hanford Site facilities. The clean water generated by these processes is occasionally enriched in tritium, and is discharged to the 200 Area State Approved Land Disposal Site (SALDS). Groundwater monitoring for tritium and other constituents is required by the state-issued permit at 22 wells surrounding the facility. During FY 2001, tritium activities in the SALDS proximal well 699-48-77A increased (maximum 670,000 pCi/L) as a result of the resumption of tritium disposal in September 2000, following a 16-month hiatus in significant tritium discharges. Well 699-48-77C, where tritium results reached a maximum value of 980,000 pCi/L, is reflecting the result of the delayed penetration of effluent deeper into the aquifer from 1999 SALDS tritium discharges. Speculation in FY 2000 (Barnett 2000b) that tritium may have reached two wells due south of the facility is probably premature. FY 2001 results indicate no departures from historical levels of tritium in these wells.

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State Approved Land Disposal Site FY1999 written by and published by . This book was released on 1999 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hanford Site 200 Area Effluent Treatment Facility (ETF) processes contaminated liquids derived from Hanford Site facilities. The clean water generated by these processes is occasionally enriched in tritium and is discharged to the 200 Area State Approved Land Disposal Site (SALDS). Groundwater monitoring for tritium and other constituents is required by the state-issued permit at 21 wells surrounding the facility. During FY 1999, average tritium activities in most wells declined from average activities in 1998. The exception was deep well 69948-77C, where tritium results were at an all-time high (77,000 pCi/L) as a result of the delayed penetration of effluent deeper into the aquifer. Of the 12 constituents with permit enforcement limits, which are monitored in SALDS proximal wells, all were within limits during FY 1999. Water level measurements in nearby wells indicate that a small hydraulic mound exists around the SALDS facility as a result of discharges. This feature is directing groundwater flow radially outward a short distance before the regional northeasterly flow predominates. Evaluation of this condition indicates that the network is currently adequate for tracking potential effects of the SALDS on the groundwater. Recommendations include the discontinuation of ammonia, benzene, tetrahydrofuran, and acetone from the regular groundwater constituent list; designating background well 299-W8-1 as a tritium-tracking well only, and the use of quadruplicate averages of field pH, instead of a single laboratory measurement, as a permit compliance parameter.

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State Approved Land Disposal Site written by and published by . This book was released on 2002 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State approved Land Disposal Site written by Douglas B. Barnett and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State approved Land Disposal Site Fiscal Year 2006 written by David B. Erb and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Results of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area State approved Land Disposal Site Fiscal Year 2005 written by Robert F. Raidl and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summary of Tritium Tracking and Groundwater Monitoring at the Hanford Site 200 Area SALDS FY 1998 written by and published by . This book was released on 1998 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treated water from the 200 Area Effluent Treatment Facility (ETF) is discharged to a disposal site in accordance with the State Waste Discharge Permit ST-4500. This disposal site is referred to as the State-Approved Land Disposal Site (SALDS). In accordance with the discharge permit, the groundwater at the SALDS is routinely sampled. The results of the groundwater sampling are reported in quarterly discharge monitoring reports. In 1997, the USDOE also committed to the issuance of an annual summary report of groundwater monitoring results and evaluation with updates to the groundwater monitoring plan as appropriate. This report summarizes the groundwater information for FY 1998.

Download or read book Groundwater Monitoring and Tritium tracking Plan for the 200 Area State approved Land Disposal Site written by Douglas B. Barnett and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tritium Monitoring in Groundwater and Evaluation of Model Predictions for the Hanford Site 200 Area Effluent Treatment Facility written by Douglas B. Barnett and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Estimating Groundwater Concentrations from Mass Releases to the Aquifer at Integrated Disposal Facility and Tank Farm Locations Within the Central Plateau of the Hanford Site written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes groundwater-related numerical calculations that will support groundwater flow and transport analyses associated with the scheduled 2005 performance assessment of the Integrated Disposal Facility (IDF) at the Hanford Site. The report also provides potential supporting information to other ongoing Hanford Site risk analyses associated with the closure of single-shell tank farms and related actions. The IDF 2005 performance assessment analysis is using well intercept factors (WIFs), as outlined in the 2001 performance assessment of the IDF. The flow and transport analyses applied to these calculations use both a site-wide regional-scale model and a local-scale model of the area near the IDF. The regional-scale model is used to evaluate flow conditions, groundwater transport, and impacts from the IDF in the central part of the Hanford Site, at the core zone boundary around the 200 East and 200 West Areas, and along the Columbia River. The local-scale model is used to evaluate impacts from transport of contaminants to a hypothetical well 100 m downgradient from the IDF boundaries. Analyses similar to the regional-scale analysis of IDF releases are also provided at individual tank farm areas as additional information. To gain insight on how the WIF approach compares with other approaches for estimating groundwater concentrations from mass releases to the unconfined aquifer, groundwater concentrations were estimated with the WIF approach for two hypothetical release scenarios and compared with similar results using a calculational approach (the convolution approach). One release scenario evaluated with both approaches (WIF and convolution) involved a long-term source release from immobilized low-activity waste glass containing 25,550 Ci of technetium-99 near the IDF; another involved a hypothetical shorter-term release of (almost equal to)0.7 Ci of technetium over 600 years from the S-SX tank farm area. In addition, direct simulation results for both release scenarios were provided to compare with the results of the WIF and convolution approaches.

Download or read book Regional Groundwater Flow and Tritium Transport Modeling and Risk Assessment of the Underground Test Area Nevada Test Site Nevada written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The groundwater flow system of the Nevada Test Site and surrounding region was evaluated to estimate the highest potential current and near-term risk to the public and the environment from groundwater contamination downgradient of the underground nuclear testing areas. The highest, or greatest, potential risk is estimated by assuming that several unusually rapid transport pathways as well as public and environmental exposures all occur simultaneously. These conservative assumptions may cause risks to be significantly overestimated. However, such a deliberate, conservative approach ensures that public health and environmental risks are not underestimated and allows prioritization of future work to minimize potential risks. Historical underground nuclear testing activities, particularly detonations near or below the water table, have contaminated groundwater near testing locations with radioactive and nonradioactive constituents. Tritium was selected as the contaminant of primary concern for this phase of the project because it is abundant, highly mobile, and represents the most significant contributor to the potential radiation dose to humans for the short term. It was also assumed that the predicted risk to human health and the environment from tritium exposure would reasonably represent the risk from other, less mobile radionuclides within the same time frame. Other contaminants will be investigated at a later date. Existing and newly collected hydrogeologic data were compiled for a large area of southern Nevada and California, encompassing the Nevada Test Site regional groundwater flow system. These data were used to develop numerical groundwater flow and tritium transport models for use in the prediction of tritium concentrations at hypothetical human and ecological receptor locations for a 200-year time frame. A numerical, steady-state regional groundwater flow model was developed to serve as the basis for the prediction of the movement of tritium from the underground testing areas on a regional scale. The groundwater flow model was used in conjunction with a particle-tracking code to define the pathlines followed by groundwater particles originating from 415 points associated with 253 nuclear test locations. Three of the most rapid pathlines were selected for transport simulations. These pathlines are associated with three nuclear test locations, each representing one of the three largest testing areas. These testing locations are: BOURBON on Yucca Flat, HOUSTON on Central Pahute Mesa, and TYBO on Western Pahute Mesa. One-dimensional stochastic tritium transport simulations were performed for the three pathlines using the Monte Carlo method with Latin hypercube sampling. For the BOURBON and TYBO pathlines, sources of tritium from other tests located along the same pathline were included in the simulations. Sensitivity analyses were also performed on the transport model to evaluate the uncertainties associated with the geologic model, the rates of groundwater flow, the tritium source, and the transport parameters. Tritium concentration predictions were found to be mostly sensitive to the regional geology in controlling the horizontal and vertical position of transport pathways. The simulated concentrations are also sensitive to matrix diffusion, an important mechanism governing the migration of tritium in fractured carbonate and volcanic rocks. Source term concentration uncertainty is most important near the test locations and decreases in importance as the travel distance increases. The uncertainty on groundwater flow rates is as important as that on matrix diffusion at downgradient locations. The risk assessment was performed to provide conservative and bounding estimates of the potential risks to human health and the environment from tritium in groundwater. Risk models were designed by coupling scenario-specific tritium intake with tritium dose models and cancer and genetic risk estimates using the Monte Carlo method. Estimated radiation doses received by individuals from chronic exposure to tritium, and the corresponding human health risks at hypothetical point-of-use locations along each of the pathlines were calculated for six potential land-use scenarios. Conservative land-use scenarios were postulated to ensure that the calculated exposures would bound any realistic dose received by individuals. Based on the human-health risk estimates, tritium exposures associated with the HOUSTON and BOURBON pathlines do not present a human health hazard off the Nevada Test Site in the present, the near term, or in the future. However, the estimates show that the TYBO pathline has the greatest potential for off-site release with a projected groundwater discharge at Oasis Valley. Using the most conservative scenario for tritium exposure demonstrates that dose could exceed the 100-mrem/yr limit at locations along the TYBO pathline.

Download or read book Results of Ground water Tracer Tests Using Tritiated Water at Oak Ridge National Laboratory Tennessee written by D. A. Webster and published by . This book was released on 1996 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ground water Levels and Tritium Concentrations at the Maxey Flats Low Level Radioative Waste Disposal Site Near Morehead Kentucky June 1984 to April 1989 written by Karen S. Wilson and published by . This book was released on 1991 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: