skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Completion Report for Well ER-4-1 Corrective Action Unit 97: Yucca Flat/Climax Mine, Revision 0

Abstract

Well ER-4-1 was drilled for the U.S. Department of Energy, Nevada National Security Administration Nevada Field Office in support of the Underground Test Area (UGTA) Activity. The well was drilled and completed from March 23 to April 13, 2016, as part of the Corrective Action Investigation Plan (CAIP) for Yucca Flat/Climax Mine Corrective Action Unit (CAU) 97. The primary purpose of the well was to collect hydrogeologic data to assist in validating concepts of the groundwater flow system within the Yucca Flat/Climax Mine CAU, and to test for potential radionuclides in groundwater from the STRAIT (U4a) underground test. The completed well includes one piezometer (p1), to a depth of 663.16 meters (m) (2,175.71 feet [ft]) below ground surface (bgs) and open from the Alluvial aquifer (AA3) to the Oak Spring Butte confining unit (OSBCU) hydrostratigraphic units; and a main completion (m1), which includes 6.625-inch (in.) casing with slotted interval (m1) installed to 906.80 m (2,975.05 ft) bgs in the Lower carbonate aquifer (LCA). A 13.375-in. diameter surface casing was installed from the surface to a depth of 809.00 m (2,654.21 ft) bgs. Well ER-4-1 experienced a number of technical issues during drilling, including borehole instability and sloughing conditions. An intermediate,more » 10.75-in./9.625-in. casing string was installed to 856.94 m (2,811.48 ft) bgs to control these issues. Borehole stability and erosion problems appear to be associated with the Tunnel Formation (Tn) and the Older tunnel beds (Ton). Overall efforts to stabilize the borehole were successful. Data collected during borehole construction include composite drill cutting samples collected every 3.0 m (10 ft), a partial suite of geophysical logs to a maximum depth of 766.57 m (2,515 ft) bgs, water-quality measurements (including tritium), water-level measurements, and two depth-discrete bailer samples collected at 538.89 m and 646.18 m (1,768 ft and 2,120 ft) bgs respectively. The well penetrated 187.45 m (615 ft) of Quaternary/Tertiary alluvium (QTa), 671.47 m (2,203 ft) of Tertiary Volcanic rocks (Tv), and 66.20 m (217.19 ft) of Paleozoic rocks (|). The stratigraphy and lithology were generally as expected with some exceptions. The top of Paleozoic rocks (|) was predicted to occur at 822.35 m (2,698 ft) bgs and was intercepted at 858.93 m (2,818 ft), a difference of 36.58 m (120 ft). As expected, the Paleozoic rocks (|) are the principal water producing formation in Well ER-4-1. Depth to water was measured after drilling as follows: In the piezometers: p1 at 320.39 m (1,051.16 ft) bgs, (measured January 4, 2017); and in the main production casing interval: m1 at 539.17 m (1,768.92 ft) bgs, (measured December 12, 2016) Geophysical logs and depth-discrete bailer sample analytical results suggest likely zones of prompt injection (underground-test-related) fission products from 472.44 to 481.48 m (1,550 to 1,580 ft) bgs and at approximately 539.50 m (1,770 ft) bgs. Subsequent work at Well ER-4-1 will be included in future reports. Field measurements for tritium were mostly below the Safe Drinking Water Act limit (20,000 picocuries per liter) with the exception of two zones showing elevated tritium concentrations. The first zone is located at approximately 365.76 to 390.14 m (1,200 to 1,280 ft) bgs and a second zone at approximately 542.54 to 566.93 m (1,780 to 1,860 ft) bgs. All Fluid Management Plan requirements were met.« less

Authors:
 [1];  [1]
  1. Navarro, Las Vegas, NV (United States)
Publication Date:
Research Org.:
Navarro, Las Vegas, NV (United States)
Sponsoring Org.:
USDOE Office of Environmental Management (EM)
OSTI Identifier:
1372646
Report Number(s):
DOE/NV-1576
DOE Contract Number:
NA0002653
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; Completion Report; Well ER-4-1; CAU 97; Yucca Flat/Climax Mine

Citation Formats

Wurtz, Jeffrey, and Rehfeldt, Ken. Completion Report for Well ER-4-1 Corrective Action Unit 97: Yucca Flat/Climax Mine, Revision 0. United States: N. p., 2017. Web. doi:10.2172/1372646.
Wurtz, Jeffrey, & Rehfeldt, Ken. Completion Report for Well ER-4-1 Corrective Action Unit 97: Yucca Flat/Climax Mine, Revision 0. United States. doi:10.2172/1372646.
Wurtz, Jeffrey, and Rehfeldt, Ken. 2017. "Completion Report for Well ER-4-1 Corrective Action Unit 97: Yucca Flat/Climax Mine, Revision 0". United States. doi:10.2172/1372646. https://www.osti.gov/servlets/purl/1372646.
@article{osti_1372646,
title = {Completion Report for Well ER-4-1 Corrective Action Unit 97: Yucca Flat/Climax Mine, Revision 0},
author = {Wurtz, Jeffrey and Rehfeldt, Ken},
abstractNote = {Well ER-4-1 was drilled for the U.S. Department of Energy, Nevada National Security Administration Nevada Field Office in support of the Underground Test Area (UGTA) Activity. The well was drilled and completed from March 23 to April 13, 2016, as part of the Corrective Action Investigation Plan (CAIP) for Yucca Flat/Climax Mine Corrective Action Unit (CAU) 97. The primary purpose of the well was to collect hydrogeologic data to assist in validating concepts of the groundwater flow system within the Yucca Flat/Climax Mine CAU, and to test for potential radionuclides in groundwater from the STRAIT (U4a) underground test. The completed well includes one piezometer (p1), to a depth of 663.16 meters (m) (2,175.71 feet [ft]) below ground surface (bgs) and open from the Alluvial aquifer (AA3) to the Oak Spring Butte confining unit (OSBCU) hydrostratigraphic units; and a main completion (m1), which includes 6.625-inch (in.) casing with slotted interval (m1) installed to 906.80 m (2,975.05 ft) bgs in the Lower carbonate aquifer (LCA). A 13.375-in. diameter surface casing was installed from the surface to a depth of 809.00 m (2,654.21 ft) bgs. Well ER-4-1 experienced a number of technical issues during drilling, including borehole instability and sloughing conditions. An intermediate, 10.75-in./9.625-in. casing string was installed to 856.94 m (2,811.48 ft) bgs to control these issues. Borehole stability and erosion problems appear to be associated with the Tunnel Formation (Tn) and the Older tunnel beds (Ton). Overall efforts to stabilize the borehole were successful. Data collected during borehole construction include composite drill cutting samples collected every 3.0 m (10 ft), a partial suite of geophysical logs to a maximum depth of 766.57 m (2,515 ft) bgs, water-quality measurements (including tritium), water-level measurements, and two depth-discrete bailer samples collected at 538.89 m and 646.18 m (1,768 ft and 2,120 ft) bgs respectively. The well penetrated 187.45 m (615 ft) of Quaternary/Tertiary alluvium (QTa), 671.47 m (2,203 ft) of Tertiary Volcanic rocks (Tv), and 66.20 m (217.19 ft) of Paleozoic rocks (|). The stratigraphy and lithology were generally as expected with some exceptions. The top of Paleozoic rocks (|) was predicted to occur at 822.35 m (2,698 ft) bgs and was intercepted at 858.93 m (2,818 ft), a difference of 36.58 m (120 ft). As expected, the Paleozoic rocks (|) are the principal water producing formation in Well ER-4-1. Depth to water was measured after drilling as follows: In the piezometers: p1 at 320.39 m (1,051.16 ft) bgs, (measured January 4, 2017); and in the main production casing interval: m1 at 539.17 m (1,768.92 ft) bgs, (measured December 12, 2016) Geophysical logs and depth-discrete bailer sample analytical results suggest likely zones of prompt injection (underground-test-related) fission products from 472.44 to 481.48 m (1,550 to 1,580 ft) bgs and at approximately 539.50 m (1,770 ft) bgs. Subsequent work at Well ER-4-1 will be included in future reports. Field measurements for tritium were mostly below the Safe Drinking Water Act limit (20,000 picocuries per liter) with the exception of two zones showing elevated tritium concentrations. The first zone is located at approximately 365.76 to 390.14 m (1,200 to 1,280 ft) bgs and a second zone at approximately 542.54 to 566.93 m (1,780 to 1,860 ft) bgs. All Fluid Management Plan requirements were met.},
doi = {10.2172/1372646},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 7
}

Technical Report:

Save / Share:
  • Well ER-3-3 was drilled for the U.S. Department of Energy, Nevada National Security Administration Nevada Field Office in support of the Underground Test Area (UGTA) Activity. The well was drilled and completed from February 21 to March 15, 2016, as part of the Corrective Action Investigation Plan (CAIP) for Yucca Flat/Climax Mine Corrective Action Unit (CAU) 97. The primary purpose of the well was to collect hydrogeologic data to assist in validating concepts of the flow system within the Yucca Flat/Climax Mine CAU, and to test for potential radionuclides in groundwater from the WAGTAIL (U3an) underground test.
  • Well ER-2-2 was drilled for the U.S. Department of Energy, Nevada National Security Administration Nevada Field Office in support of the Underground Test Area (UGTA) Activity. The well was drilled from January 17 to February 8, 2016, as part of the Corrective Action Investigation Plan (CAIP) for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada. The primary purpose of the well was to collect hydrogeologic data to evaluate uncertainty in the flow and transport conceptual model and its contamination boundary forecasts, and to detect radionuclides in groundwater from the CALABASH (U2av) underground test. Well ER-2-2 was notmore » completed as planned due to borehole stability problems. As completed, the well includes a piezometer (p1) to 582 meters (m) (1,909 feet [ft]) below ground surface (bgs) installed in the Timber Mountain lower vitric-tuff aquifer (TMLVTA) and a 12.25-inch (in.) diameter open borehole to 836 m (2,743 ft) bgs in the Lower tuff confining unit (LTCU). A 13.375-in. diameter carbon-steel casing is installed from the surface to a depth of 607 m (1,990 ft) bgs. Data collected during borehole construction include composite drill cutting samples collected every 3.0 m (10 ft), geophysical logs to a depth of 672.4 m (2,206 ft) bgs, water-quality measurements (including tritium), water-level measurements, and slug test data. The well penetrated 384.05 m (1,260 ft) of Quaternary alluvium, 541.93 m (1,778 ft) of Tertiary Volcanics (Tv) rocks, and 127.71 m (419 ft) of Paleozoic carbonates. The stratigraphy and lithology were generally as expected. However, several of the stratigraphic units were significantly thicker then predicted—principally, the Tunnel formation (Tn), which had been predicted to be 30 m (100 ft) thick; the actual thickness of this unit was 268.22 m (880 ft). Fluid depths were measured in the borehole during drilling as follows: (1) in the piezometer (p1) at 552.15 m (1,811.53 ft) bgs and (2) in the main casing (m1) at 551.69 m (1,810.01 ft) bgs. As expected, field measurements for tritium were above the Safe Drinking Water Act limit (20,000 picocuries per liter) for a portion of the Tertiary volcanic section near the water table. Tritium concentrations were at or near the field detection limit in the Lower carbonate aquifer (LCA) while drilling. During drilling, a sample was collected while circulating in the LCA. The sample was submitted for off-site laboratory analysis. The sample results indicated low but measurable tritium concentrations. All Fluid Management Plan requirements were met during drilling activities.« less
  • Well ER-6-2 and its satellite hole, Well ER-6-2 No.1, were drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. Well ER-6-2 was drilled in two stages in 1993 and 1994; the satellite hole, Well ER-6-2 No.1 was drilled nearby in 1993 but was abandoned. The wells were drilled as part of a hydrogeologic investigation program for the Yucca Flat-Climax Mine Corrective Action Unit Number 97, in the northeastern portion of the Nevada Test Site. The wells are located inmore » Yucca Flat, within Area 6 of the Nevada Test Site. The wells provided information regarding the radiological and hydrogeological environment in a potentially down-gradient position from tests conducted in northern and central Yucca Flat. Construction of Well ER-6-2 began with a 1.2-meter-diameter surface conductor hole, which was drilled and cased off to a depth of 30.8 meters below the surface. A 50.8-centimeter diameter surface hole was then rotary drilled to the depth of 578.5 meters and cased off to the depth of 530.4 meters. The hole diameter was then reduced to 27.0 centimeters, and the borehole was advanced to a temporary depth of 611.4 meters. The borehole was conventionally cored to a total depth of 1,045 meters with a diameter of 14.0 centimeters. Borehole sloughing required cementing and re-drilling of several zones. The open-hole completion accesses the lower carbonate aquifer, the CP thrust fault, and the upper clastic confining unit. A fluid level depth of 543.2 meters was most recently measured in the open borehole in September 2007. No radionuclides were encountered during drilling. The satellite hole Well ER-6-2 No.1 was drilled approximately 15.2 meters north of Well ER-6-2 on the same drill pad. This was planned to be used as an observation well during future hydrologic testing at Well ER-6-2; however, the satellite hole was abandoned at the depth of 399 meters due to stuck drill pipe, and was subsequently cemented to the surface. Detailed lithologic descriptions with stratigraphic assignments in this report are based on composite drill cuttings samples collected every 3 meters, cores taken between the depths of 619.3 and 1,042.4 meters, and geophysical log data. Stratigraphic assignments within the Paleozoic section are based on paleontological analyses. The well was collared in alluvium and at 30.8 meters penetrated Paleozoic carbonate rocks. These consisted of dolostone with minor shale and limestone of the Bonanza King Formation, and limestone with minor quartzite, sandstone, and dolostone assigned to the Guilmette Formation. The borehole reached total depth in a shale unit assigned to the Chainman Shale. The units below the Bonanza King Formation are overturned due to faulting and folding and, therefore, are stratigraphically upside-down.« less
  • Well ER-2-2 was drilled for the U.S. Department of Energy, Nevada National Security Administration Nevada Field Office in support of the Underground Test Area (UGTA) Activity. The well was drilled from January 17 to February 8, 2016, as part of the Corrective Action Investigation Plan (CAIP) for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada. The primary purpose of the well was to collect hydrogeologic data to evaluate uncertainty in the flow and transport conceptual model and its contamination boundary forecasts, and to detect radionuclides in groundwater from the CALABASH (U2av) underground test. Well ER-2-2 was notmore » completed as planned due to borehole stability problems. As completed, the well includes a piezometer (p1) to 582 meters (m) (1,909 feet [ft]) below ground surface (bgs) installed in the Timber Mountain lower vitric-tuff aquifer (TMLVTA) and a 12.25-inch (in.) diameter open borehole to 836 m (2,743 ft) bgs in the Lower tuff confining unit (LTCU). A 13.375-in. diameter carbon-steel casing is installed from the surface to a depth of 607 m (1,990 ft) bgs. Data collected during borehole construction include composite drill cutting samples collected every 3.0 m (10 ft), geophysical logs to a depth of 672.4 m (2,206 ft) bgs, water-quality measurements (including tritium), water-level measurements, and slug test data. The well penetrated 384.05 m (1,260 ft) of Quaternary alluvium, 541.93 m (1,778 ft) of Tertiary Volcanics (Tv) rocks, and 127.71 m (419 ft) of Paleozoic carbonates. The stratigraphy and lithology were generally as expected. However, several of the stratigraphic units were significantly thicker then predicted—principally, the Tunnel formation (Tn), which had been predicted to be 30 m (100 ft) thick; the actual thickness of this unit was 268.22 m (880 ft). Fluid depths were measured in the borehole during drilling as follows: (1) in the piezometer (p1) at 552.15 m (1,811.53 ft) bgs and (2) in the main casing (m1) at 551.69 m (1,810.01 ft) bgs. As expected, field measurements for tritium were above the Safe Drinking Water Act limit (20,000 picocuries per liter). All Fluid Management Plan requirements were met.« less
  • This corrective action decision document (CADD)/corrective action plan (CAP) has been prepared for Corrective Action Unit (CAU) 97, Yucca Flat/Climax Mine, Nevada National Security Site (NNSS), Nevada. The Yucca Flat/Climax Mine CAU is located in the northeastern portion of the NNSS and comprises 720 corrective action sites. A total of 747 underground nuclear detonations took place within this CAU between 1957 and 1992 and resulted in the release of radionuclides (RNs) in the subsurface in the vicinity of the test cavities. The CADD portion describes the Yucca Flat/Climax Mine CAU data-collection and modeling activities completed during the corrective action investigationmore » (CAI) stage, presents the corrective action objectives, and describes the actions recommended to meet the objectives. The CAP portion describes the corrective action implementation plan. The CAP presents CAU regulatory boundary objectives and initial use-restriction boundaries identified and negotiated by DOE and the Nevada Division of Environmental Protection (NDEP). The CAP also presents the model evaluation process designed to build confidence that the groundwater flow and contaminant transport modeling results can be used for the regulatory decisions required for CAU closure. The UGTA strategy assumes that active remediation of subsurface RN contamination is not feasible with current technology. As a result, the corrective action is based on a combination of characterization and modeling studies, monitoring, and institutional controls. The strategy is implemented through a four-stage approach that comprises the following: (1) corrective action investigation plan (CAIP), (2) CAI, (3) CADD/CAP, and (4) closure report (CR) stages.« less