Borehole Data Package for 1998 Wells Installed at Single-Shell Tank Waste Management Area TX-TY

Horton, DG; Hodges, FN

doi:10.2172/4722

Cited by 3 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 315 mg/L nitrate value from well 299-W14-13 is a mixture of the high nitrate-bearing water at the top of the aquifer with lower nitratebearing water deeper in the screened interval. The proposed distribution of nitrate in the screened interval is supported by the trend in specific conductance discussed above (Figure 4.34 Previously, in 1999, groundwater samples were collected by pumping during drilling of well 299-W14-14 east of TX Tank Farm (Horton and Hodges 1999). Each sample interval was isolated by packers before sampling.…”

Section: 49mentioning

confidence: 63%

Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas

Horton¹

2007

View full text Add to dashboard Cite

Aquifer testing has shown that vertical hydraulic gradients exist in some wells in the 200 West Area. Vertical flow is upward in some places and downward in other places. The reason for the vertical flow is not known for certain. Nevertheless, vertical flow has important implications pertaining to (1) the representativeness of groundwater samples collected from monitoring wells and (2) the vertical distribution of contaminants in the aquifer.The major contaminants of concern in the groundwater below and locally adjacent to all single-shell tank waste management areas (WMAs) in 200 West Area are carbon tetrachloride, technetium-99, and nitrate. Chromium and tritium are contaminants present at WMAs T, TX-TY, and S-SX; iodine-129 is of concern at WMA TX-TY and fluoride is of concern at WMA T. The groundwater contaminants of concern below all single-shell tank WMAs in 200 East Area are nitrate, technetium-99, and tritium. Sulfate, uranium, cobalt-60, and cyanide are also of concern at WMA B-BX-BY, and cyanide is of concern at WMA C.Vertical concentration gradients are known to exist in the upper unconfined aquifer at several singleshell tank WMAs:• Around WMA T, maximum technetium-99 concentrations occur at the water table in some wells and 10 m below the water table in other wells east of the WMA.• Around WMA TX-TY, maximum concentrations of nitrate, technetium-99, and iodine-129 are within 1 m of the water table in the high concentration plume east of the WMA.• Around WMA S-SX, chromium, nitrate, and technetium-99 are present throughout the upper 23 m of the unconfined aquifer near the center of the plume south of the WMA. Technetium-99 and nitrate decrease rapidly with depth in the aquifer at a well near the northern edge of the plume.• Around WMA B-BX-BY, the concentration of tritium increases with increasing depth at one well. The concentrations of technetium-99 and nitrate are high in a zone at the base of the aquifer in another well at WMA B-BX-BY. ivThe vertical concentration gradients are probably a function of several characteristics including distance to source area, salinity of waste fluids, and vertical hydraulic flow in the wells.Comparing the nitrate, technetium-99, and chromium concentrations in groundwater with concentrations in pore water representing leaked tank fluids suggests that tank waste has influenced groundwater at WMA T and WMA S-SX. Similar comparisons at WMA TX-TY and WMA B-BX-BY do not show similarities between groundwater, pore water and estimated tank fluid composition.v

show abstract

Section: 49mentioning

confidence: 63%

Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas

Horton¹

2007

View full text Add to dashboard Cite

show abstract

“…• additional routine, quarterly sampling data collected from the existing network from January 1998 through December 2001. Supporting information (e.g., drilling information and hydrologic testing raw data) for this report are available in the project files of the Hanford Groundwater Monitoring Project at Pacific Northwest National Laboratory (PNNL) and in the borehole data packages for the new wells that were drilled during the report period (Horton and Hodges 1999, 2000, 2001Horton 2002a). Hodges and Chou (2001) described the objectives and general approach for assessment of groundwater quality at WMA TX-TY.…”

Section: Scopementioning

confidence: 99%

“…Details on the drilling and construction of new wells and on the geologic conditions encountered during drilling can be found in the borehole completion reports (Horton and Hodges 1999, 2000, 2001Horton 2002a).…”

Section: Description Of New Wellsmentioning

confidence: 99%

“…Similar lithologic changes are suggested by wireline geophysical surveys for the screened interval in wells 299-W15-40 and 299-W15-763 and by the geologist's log and/or sieve analyses for wells 299-W10-27, 299-W14-14, 299-W14-15, 299-W14-16, and 299-W14-18. The geologists' logs, borehole geophysical logs, and sieve data are in the borehole completion reports for the wells (Horton and Hodges 1999, 2000, 2001Horton 2002a).…”

Section: Description Of New Wellsmentioning

confidence: 99%

“…These differences suggest Well (b) Date Drilled Drilling Method Screen Interval Depth (m) (c) Pump Intake Depth (m) (c) Total Drill Depth (m) (c) Depth to Water (d) (c) Pump Intake Depth (m) (c) Total Drill Depth (m) (c) Depth to Water (d) 76.2 to 77.7 m depth is gravel; 77.7 to 80.6 m depth is sandy gravel; 80.6 to 80.7 m depth is gravel. (e) (a) Information on well construction is from Horton and Hodges (1999, 2000, 2001 and Horton (2002a). differences in recovery rates, which may reflect differences in lithology.…”

Section: Description Of New Wellsmentioning

confidence: 99%

See 2 more Smart Citations

RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001)

Horton¹

2002

View full text Add to dashboard Cite

Waste Management Area (WMA) TX-TY at the Hanford Site contains the TX and TY single-shell tank farms and their auxiliary equipment. These tank farms, located in the northern portion of the 200 West Area, include 24 single-shell carbon steel tanks constructed in the 1940s and early 1950s. During operations, tanks received mixed waste from plants that processed spent reactor fuel to recover plutonium as part of Hanford's defense mission. The tank farms ceased active operations in 1980 but are currently storing waste and are currently regulated as Resource Conservation and Recovery Act (RCRA) Interim Status Facilities. Waste Management Area TX-TY was placed in RCRA Groundwater Quality Assessment in 1993 and has remained in that status because of indications that dangerous-waste contaminants from within the area may be entering groundwater. The water table is declining and groundwater flow directions are changing in the vicinity of WMA TX-TY. These changes are a result of the cessation of effluent discharge to ground in 1995 and the initiation of a major pump-and-treat operation in 1998. To meet the changing groundwater monitoring needs, twelve new RCRA monitoring wells have been constructed since 1997 and two others are in the planning stage. Monitoring at WMA TX-TY indicates that the dangerous-waste constituent chromium occurs above the drinking water maximum contaminant level at one well east of the WMA. Although the nearest potential source for the chromium is the WMA and the chromium is attributed to the WMA, the high concentrations of chromium appear to be deeper in the aquifer than the maximum concentrations of nonregulated technetium-99, which is most likely from WMA TX-TY. Chromium contamination is located on the downgradient (east) side of the WMA and is currently migrating to the southeast. The dangerous-waste constituent carbon tetrachloride is also present at WMA TX-TY. The carbon tetrachloride is from a well document, upgradient source associated with the Plutonium Finishing Plant. Data gathered during drilling indicates that the carbon tetrachloride is distributed relatively deep in the upper part of the aquifer at WMA TX-TY.

show abstract

Groundwater Conditions at Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001)

Horton¹

2002

View full text Add to dashboard Cite

Waste Management Area (WMA) TX-TY at the Hanford Site contains the TX and TY single-shell tank farms and their auxiliary equipment. These tank farms, located in the northern portion of the 200 West Area, include 24 single-shell carbon steel tanks constructed in the 1940s and early 1950s. During operations, tanks received mixed waste from plants that processed spent reactor fuel to recover plutonium as part of Hanford's defense mission. The tank farms ceased active operations in 1980 but are currently storing waste and are currently regulated as Resource Conservation and Recovery Act (RCRA) Interim Status Facilities. The water table is declining and groundwater flow directions are changing in the vicinity of WMA TX-TY. These changes are a result of the cessation of effluent discharge to ground in 1995 and the initiation of a major pump-and-treat operation in 1997. To meet the changing groundwater monitoring needs, twelve new RCRA monitoring wells have been constructed since 1997 and two others are in the planning stage. Monitoring at WMA TX-TY indicates that chromium occurs above the drinking water maximum contaminant level at one well east of the WMA. Although the nearest potential source for the chromium is the WMA, the high concentrations of chromium appear to be deeper in the aquifer than the maximum concentrations of technetium-99. The most likely source for the technetium-99 and associated nitrate is WMA TX-TY. These constituents are located on the downgradient (east) side of the WMA and are currently migrating to the southeast. A second plume is located south of the WMA. This technetium-99 plume is found in one well and is the result of altered groundwater flow directions in the area caused by the 200-ZP-1 pump-and-treat operations. Data gathered during drilling indicate that carbon tetrachloride, tritium, and much of the nitrate result from past-practice activities and are distributed relatively deep in the upper part of the aquifer. Tank waste is found predominantly near the surface of the aquifer.

show abstract

Borehole Data Package for 1998 Wells Installed at Single-Shell Tank Waste Management Area TX-TY

Cited by 3 publications

References 0 publications

Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas

Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas

RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001)

Groundwater Conditions at Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001)

Contact Info

Product

Resources

About