Texas

Pantex

(Exxon) Ray Point

Texas

Falls City Site

(Conoco) Conquista Site

(Chevron) Panna Maria Site

Long-Term Stewardship Site Highlights

(Chevron) Panna Maria Site (page 3) Major Activities- disposal cell monitoring; groundwater monitoring; access restrictions; erosion control; maintenance; inspections Site Size- 121 hectares (300 acres) Start/End Years- 2001/in perpetuity Estimated Average Annual Cost FY 2000-2006-$26,100

(Conoco) Conquista Site (page 7) Major Activities - groundwater monitoring; disposal cell monitoring; inspections; access restrictions Site Size- 243 hectares (600 acres) Start/End Years- 2002/in perpetuity Estimated Average Annual Cost FY 2000-2006-$38,943

(Exxon) Ray Point Site (page11) Major Activities -disposal cell monitoring; inspections; access restrictions Site Size- 24 hectares (60 acres) Start/End Years- 2001/in perpetuity Estimated Average Annual Cost FY 2000-2006- $25,600

Falls City Site (page 15) Major Activities- groundwater monitoring; disposal cell monitoring and maintenance; inspections; access restrictions Site Size- 96 hectares (232 acres) Start/End Years- 1997/in perpetuity Estimated Average Annual Cost FY 2000-2006- $139,300

Pantex Plant (page 21) Major Activities- groundwater and soil cleanup; groundwater monitoring Site Size- 4,119 hectares (10, 177 acres) Estimated Average Annual Cost FY 2000-2006- $1.4 million

DJOHNSON

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Table of Contents

Table of Contents

(Chevron) Panna Maria Site ............................................................... 3

(Conoco) Conquista Site .................................................................. 7

(Exxon) Ray Point Site .................................................................. 11

Falls City Site .......................................................................... 15

Pantex Plant ........................................................................... 21

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National Defense Authorization Act (NDAA) Long-Term Ste\Htrdship Report

Texas 2


(CHEVRON) PANNA MARIA SITE

1.0 SITE SUMMARY

1.1 Site Description and Mission

The (Chevron) Panna Maria Site is the location of a former uranium milling site that operated from 1979 to 1992. The 121-hectare (300-acre) site is owned by the Chevron Corporation and is located in Karnes County in southern Texas. The Chevron Corporation operated the mill to process uranium ore for commercial purposes. Wastes from the ore processing operations are consolidated in the onsite disposal cell, which comprises 61 hectares (150 acres) of the site.

The current mission of the site is to complete remediation. The (Chevron) Panna Maria Site is subject to Title II of the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). UMTRCA Title II sites are privately owned and operated sites that were licensed when UMTRCA was passed, or thereafter. The majority of the mining and milling

LONG-TERM STEWARDSHIP HIGHLIGHTS

Major Long-Term Stewardship Activities - disposal cell monitoring; groundwater monitoring; access restrictions; erosion control; maintenance; inspections Total Site Area- 121 hectares (300 acres) Estimated Volume of Residual Contaminants- disposal cell 5.7 million cubic meters (7 .4 million cubic yards); groundwater unknown Long-Term Stewardship Start-End Years- 2001-in perpetuity Average Annual Long-Term Stewardship Cost FY 2000-2006-$26,100 Landlord- currently Chevron Corporation; beginning in 2001, the U.S. Department of Energy's Grand Junction Office

conducted at these sites was for the private sale of uranium, but a portion of the uranium may have been sold to the U.S. Government. None of the ore milled at the (Chevron) Panna Maria Site was sold to the U.S. Government. As such, DOE is responsible for long-term stewardship activities but not remediation of the site. Based on ongoing discussions with the Texas Bureau of Radiation Control, DOE anticipates that the (Chevron) Panna Maria Site will be transferred from Chevron Corporation to DOE in 2001. Once the site is transferred to DOE, its only mission will be long-term surveillance and maintenance of the disposal cell, and monitoring of the groundwater.

1.2 Site Cleanup and Accomplishments

The Chevron Corporation is currently completing reclamation activities at the site. Approximately 5.7 million cubic meters (7 .4 million cubic yards) of mill tailings from the former tailings pond, as well as contaminated soil and construction debris, will be encapsulated onsite. The mill tailings, soil, and construction debris are contaminated with uranium, radium, and thorium. Current plans are to consolidate all contaminated materials in an onsite engineered disposal cell. The disposal cell will be capped when remediation activities are completed. Soils surrounding the site will be remediated to levels that comply with standards set by the U.S. Environmental Protection Agency (EPA).

Groundwater at the site is contaminated with uranium as a result of the former uranium processing activities. The specific groundwater remediation strategy has not yet been determined but information from the Texas Bureau of Radiation Control indicates that alternate concentration limits (ACLs ), cleanup standards that are based on site-specific considerations, have been sought for, and active remediation will not continue. For ACLs to be approved, evidence must be provided that the ACLs will not adversely impact human health or the environment.

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National Defense Authorization Act (NDAA) Long-Term Stewardshi)J Report

2.0 SITE-WIDE LONG-TERM STEWARDSHIP

2.1 Long-Term Stewardship Activities

The DOE Grand Junction Office will begin conducting long-term stewardship activities at the (Chevron) Panna Maria Site in 2001, when the site is transferred to DOE. To terminate the site's radioactive material license, Chevron Corporation must conduct state-approved reclamation of any onsite radioactive waste. The Texas Bureau of Radiation Control will then determine when the site will be transferred to DOE for custody and long-term care. For the site to be transferred to DOE, the Chevron Corporation must make a one-time payment to the U.S. Treasury fully funding inspections and anticipated maintenance.

Access to the site will be restricted through the use of fencing and posting warning signs, as necessary, along the site boundary. Fences and signs will be repaired or replaced on an asneeded basis. DOE will staff a 24-hour phone line for reporting site concerns. Drilling and other intrusive activities will be prevented within site boundaries through the use of institutional controls.

Site records will be kept in permanent storage at the DOE Grand Junction Office in Colorado.


The types of records that will be maintained include site characterization data, remedial action design information, the site completion report, long-term monitoring plans, annual inspection reports, and current and historical monitoring data. A report is submitted annually to the U.S. Nuclear Regulatory Commission (NRC) that summarizes, describes, and evaluates all surveillance and maintenance actions, as required under Title 10 of the Code of Federal Regulations, Part 40.

2.2 Specific Long-Term Stewardship Activities

Engineered Unit

The disposal cell will cover approximately 61 hectares (150 acres) of the 121-hectare (300-acre) site area. The cell will be designed with a low-permeability radon barrier and a grass surface layer for erosion control. Erosion control will be provided for all potentially vulnerable features, and the site will be graded to provide positive drainage. All disturbed areas will be revegetated.

Texas

STAKEHOWER INVOLVEMENT

When licensed and transferred to DOE, copies of the annual inspection report for the (Chevron) Panna Maria Site will be distributed to the local library and any stakeholders requesting them. The annual inspection report will also be available on the DOE Grand Junction Office website at: www.doegjpo.com.

4


DOE will conduct annual inspections to ensure the integrity of the cell cover and other engineered features, the effectiveness of institutional controls, and the compliance of the disposal cell with applicable requirements. The disposal cell at the (Chevron) Panna Maria Site will be designed and constructed to last for remain effective for 200 to 1,000 years, in accordance with EPA standards. However, DOE's responsibility for the safety and integrity of the disposal cell is expected to continue in perpetuity.

Groundwater

Annual groundwater monitoring will be conducted at the (Chevron) Panna Maria Site to ensure that the site is in compliance with ACLs, if approved, and to demonstrate the effectiveness of the engineered disposal cell in isolating the encapsulated wastes from the local environment. Groundwater monitoring is expected to continue in perpetuity.

2.3 Regulatory Regime

Remediation of the (Chevron) Panna Maria Site is expected to be complete by 2001. Following NRC concurrence that cleanup has been achieved, NRC will issue a general license for the long-term care of the residual radioactive disposal cell (contained in Title 10 of the Code of Federal Regulations, Part 40.28). The purpose of the license is to ensure the site will be cared for in a manner that protects human health and safety and the environment. The license also represents that NRC formally accepts the site-specific long-term surveillance plan.

Long-term stewardship activities at the (Chevron) Panna Maria Site are governed by several requirements in the following regulations: UMTRCA; the Atomic Energy Act of 1954, as amended; EPA Groundwater Protection Standards, including Title 40 ofthe Code of Federal Regulations, Part 192, Subparts D and E; and the National Environmental Policy Act of 1969, as amended.

2.4 Assumptions and Uncertainties

Long-term stewardship costs are estimated based on actual long-term stewardship costs at similar sites currently managed by DOE. However, actual costs may vary as a result of the remediation strategies employed by the Chevron Corporation.

DOE assumes that groundwater monitoring will only be necessary on an annual basis and that ACLs will be applied to the groundwater contamination underlying the site.

The site is expected to be transferred to DOE in 2001.

3.0 ESTIMATED LONG-TERM STEWARDSHIP COSTS

The costs estimated for fiscal year (FY) 2000 are associated with preparing the site's long-term surveillance plan, and preparing the site for transfer from Chevron Corporation to DOE. The costs estimated for the remaining years are for monitoring and maintenance of the disposal cell and monitoring of the groundwater, and reflect the assumptions listed above.

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National Defense Authorization Act (NDAA) Long-Term Stewardship Report

Site Long-Term Stewardship Costs (Constant Year 2000 Dollars)

Year(s) Amount Year(s) Amount Year(s) Amount

FY 2000 $5,200 FY 2008 $35,100 FY 2036-2040 $170,500

FY 2001 $41,600 FY 2009 $35,000 FY 2041-2045 $170,400

FY 2002 $36,100 FY 2010 $34,300 FY 2046-2050 $170,500

FY 2003 $34,900 FY 2011-2015 $163,500 FY 2051-2055 $170,400

FY 2004 $35,300 FY 2016-2020 $159,200 FY 2056-2060 $170,500

FY 2005 $35,500 FY 2021-2025 $159,700 FY 2061-2065 $170,400

FY 2006 $34,800 FY 2026-2030 $168,700 FY 2066-2070 $170,500

FY 2007 $35,300 FY 2031-2035 $170,400

4.0 FUTURE USES

Once the site's license is transferred to DOE in 2001, activity at the site is expected to be restricted to long-term monitoring and maintenance of the disposal cell and long-termmonitoring of the groundwater. Under UMTRCA provisions, public access to the disposal cell will be restricted indefinitely.

For more information about the (Chevron) Panna Maria Site, please contact:

Art Kleinrath, Long-Term Surveillance and Maintenance Program Manager U.S. Department of Energy, Grand Junction Office 2597 B3/4 Road, Grand Junction, CO 81503 Phone: 970-248-6037 or visit the Internet website at http://www.doegjpo.com

Texas 6


(CONOCO) CONQUISTA SITE

1.0 SITE SUMMARY


The (Conoco) Conquista Site is located in Karnes County, Texas, southwest of Falls City. The (Conoco) Conquista Site is a uranium milling site site owned and operated by the Continental Oil Company (CONOCO). The (Conoco) Conquista Site encompasses 243 hectares (600 acres) and has an onsite, 101-hectare (250-acre) mill tailings disposal cell.

CONOCO's current site llliSSlon is to complete remediation activities. Once remediation is complete and the site is transferred to the U.S. Department of Energy's (DOE) Grand Junction Office in 2002, DOE's sole mission at the site will be to conduct long-term stewardship activities.

In the early 1970s, CONOCO, in cooperation with Pioneer Nuclear Corporation, began a venture known as


Major Long-Term Stewardship Activitiesgroundwater monitoring; disposal cell monitoring; inspections; access restrictions Total Site Area- 243 hectares (600 acres) Estimated Volume of Residual Contaminants- disposal cell5.9 million cubic meters (6.5 million cubic yards); groundwater unknown Long-Term Stewardship Start-End Years- 2002-in perpetuity Average Annual Long-Term Stewardship Cost FY 2000-2006- $38,943 Landlord- Continental Oil Company; U.S. Department of Energy, Grand Junction Office (beginning in 2002)

the Conquista Project to mine uranium and build and operate a 1,750-ton-per-day processing mill southwest of Falls City in Karnes County. The project called for mining ore by open pit methods within a 56-kilometer (35-mile radius) of the plant and hauling it back to the mill by truck. Mining began in 1971, followed by milling operation between 1972 and 1982.

The (Conoco) Conquista Site is subject to Title II of the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). UMTRCA Title II sites are privately owned and operated sites that were licensed when the Act was passed or thereafter. The majority of the uranium produced at these sites was for private sale, but a portion was sold to the U.S. Government. Under UMTRCA Title ll, DOE is responsible for long-term stewardship activities, by the site's owner, CONOCO, is responsible for remediation.


Remedial actions at the site of the former uranium milling site were carried out by CONOCO under provisions of UMTRCA. The cost of the (Conoco) Conquista Site's reclamation and closure is borne by CONOCO, the commercial owner of the processing facility. CONOCO began decommissioning the site in 1982, and finished in 1984. The site's closure plan was submitted in 1987 and was approved in 1988, at which time the site was reclaimed to comply with applicable standards. Mill tailings, contaminated soils, and construction debris were remediated to EPA standards, and then disposed of in an unlined disposal cell. The cell was then capped with grass and soil. The cell encompasses approximately 101 hectares (250 acres), and is designed and located to achieve maximum protection from erosion and other geologic or environmental hazards, as well as provide the required protection of human health and safety and the environment. The volume of the residual contamination in the disposal cell is approximately 5.9 million cubic meters (6.5 million cubic yards). The strip mines have been converted into fish-stocked ponds, and the mill's remediated tailings pond was converted into a sustainable hay-growing business.

The groundwater at the site is believed to be contaminated by radionuclides, including radium and uranium. No

Texas 7

National Defense Authorization Act (NDAA) Long-Term Stewm·dship Report

groundwater remediation has occurred, and supplemental standards, as defined in Title 40 of the Code ofF ederal Regulations Part 192.22, will likely be applied. Groundwater monitoring will be required to ensure compliance with the supplemental standards and the effectiveness of the disposal cell. A request has not yet been made for the application of supplemental standards to the contaminated groundwater. CONOCO is working with the State of Texas (an Agreement State) to determine if supplemental standards can be used, and will be submitting a request to the State of Texas in the near future.



The (Conoco) Conquista Site will be transferred to DOE's Grand Junction Office in 2002 for custody and long-term care. Upon transfer, DOE will be responsible for conducting long-term stewardship activities, including groundwater and disposal cell monitoring. DOE will be responsible for ongoing regulatory compliance at the site. DOE will inspect the site and report site conditions to the NRC annually. Inspection parameters will be developed as part of the site's long-term surveillance plan.

The site inspections will identify conditions that might affect site integrity. The recommended changes will be evaluated, and DOE will conduct any needed maintenance or monitoring. Maintenance activities could include repairs to fences and site access controls; adjustments to drainage and construction of drainage structures to correct erosion problems; and vegetation control, including periodic mowing. Specific environmental monitoring activities will be specified in the long-term surveillance plan. Monitoring will likely include an annual


inspection to ensure the integrity of the cell cover and other engineered features, and to ensure that institutional controls are effective and the site complies with applicable requirements.

Access to the site will be restricted through the use of fencing and posting warning signs, as necessary, along the site boundary. DOE will staff a 24-hour phone line for reporting site concerns. Drilling and other intrusive activities will be prevented within site boundaries through institutional control.

Site records will be kept in permanent storage at the DOE Grand Junction Office in Grand Junction, Colorado. The types of records to be kept include characterization data, the remedial action design, the completion report, the long-term monitoring plan, annual inspection reports, and monitoring data.

Texas 8


Groundwater

This site has residually contaminated groundwater underlying the area around the cell. It is likely the groundwater is contaminated by radionuclides, including radium and uranium. Specific monitoring requirements will be prescribed in the site's long-term

( Conoco) Conquista Site

STAKEHOWER INTERACTION

When licensed and transferred to DOE, the annual inspection report for the (Conoco) Conquista Site will be distributed to the local libraries and any stakeholder requesting one. The report will also be published on the GJO website at www.doegjpo.com.

surveillance plan. However, it is likely that the groundwater will require annual monitoring for an unspecified period of time to ensure the effectiveness of the selected cleanup remedy and compliance with supplemental standards, as defined in Title 40 of the Code ofF ederal Regulations Part 192.22.

Engineered Units

DOE will conduct annual inspections of the disposal cell to ensure the integrity of the cap and other engineered features. Maintenance and repairs will be conducted on an as-needed basis. Long-term stewardship activities will continue for the disposal cell in perpetuity. The disposal cell will have access controls that include warning signs and a fence with locked gates.


Long-term stewardship activities at the (Conoco) Conquista Site will be governed by several requirements in the following regulations: UMTRCA; the Atomic Energy Act of 1954, as amended; Title 10 of the Code of Federal Regulations Part 40; and the National Environmental Policy Act of 1969.


DOE assumes that it will be responsible for long-term stewardship activities at the site starting in 2002.

DOE assumes the frequency of groundwater monitoring will be comparable to the groundwater monitoring frequency at similar sites.

The approval and application of supplemental standards, as defined in Title 40 of the Code of Federal Regulations Part 192.22, to the site's contaminated groundwater is also anticipated.

The disposal cell cap is not expected to be replaced for a least 200 years.

3.0 ESTIMATED LONG· TERM STEWARDSHIP COSTS

The cost estimate for the (Conoco) Conquista Site is based on the known long-term stewardship activity costs at other sites managed by DOE's Grand Junction Office that are similar to the (Conoco) Conquista Site.

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National Defense Authorization Act (NDAA) Long-Term Ste\\ardship Report

Site Long-Term Stewardship Costs (Constont Year2000Dollars)


FY 2000 $4,700 FY 2008 $52,700 FY 2036-2040 $255,700

FY 2001 $3,100 FY 2009 $52,600 FY 2041-2045 $255,700

FY 2002 $54,200 FY 2010 $51,500 FY 2046-2050 $255,800

FY 2003 $52,300 FY 2011-2015 $245,300 FY 2051-2055 $255,700

FY 2004 $52,900 FY 2016-2020 $238,700 FY 2056-2060 $255,700

FY 2005 $53,200 FY 2021-2025 $239,500 FY 2061-2065 $255,800

FY 2006 $52,200 FY 2026-2030 $253,100 FY 2066-2070 $255,700

FY 2007 $53,000 FY 2031-2035 $255,700

4.0 FUTURE USES

The site will be a permanent uranium mill tailings repository and will continue to be used for hay production. Once NRC includes the site within DOE's general license for custody and long-term care in 2002, the disposal site will be owned by the Federal Government, which will control land use within site boundaries. DOE will perform long-term stewardship activities, as required under the NRC general license, to maintain protectiveness and regulatory compliance.

For more information about the (Conoco) Conquista Site, contact:


Texas 10

(Exxon) Ray Point Site

(EXXON) RAY POINT SITE

1.0 SITE SUMMARY


The (Exxon) Ray Point Site is a privately owned and operated site that was formerly used for the milling of uranium ore. The site is located near the southern Texas town of Ray Point, approximately 113 kilometers (70 miles) southeast of San Antonio. The site covers approximately 24 hectares (60 acres) and has a 16-hectare (39-acre) onsite disposal cell for wastes that were generated during uranium mining operations.

The current mission of the site is to complete remediation of onsite radioactive mill tailings and waste. The (Exxon) Ray Point Site is subject to Title II of the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). UMTRCA Title II sites are privately


Major Long-Term Stewardship Activities - disposal cell monitoring; inspections; access restrictions Total Site Area- 24 hectares (60 acres) Estimated Volume of Residual Contaminants- disposal cell275,400 cubic meters (360,000 cubic yards) Long-Term Stewardship Start-End Years- 2001-in perpetuity Average Annual Long-Term Stewardship Cost FY 2000-2006- $25,600 Landlord- U.S. Department of Energy, Grand Junction Office (beginning in 2001)

owned and operated sites that were licensed when UMTRCA was passed, or thereafter. The majority of the mining and milling conducted at these sites was for the private sale of uranium, but a portion of the uranium was sold to the U.S. Government. As such, the U.S. Department of Energy (DOE) is responsible for long-term stewardship activities but not remediation of the site. Based on ongoing discussions with the Texas Bureau of Radiation Control, DOE expects that the (Exxon) Ray Point Site will be transferred from Exxon Corporation (now called Exxon Mobil Corporation) to DOE's Grand Junction Office in 2001 for long-term stewardship. At that time, the only mission for the site will be the ongoing monitoring and maintenance of the disposal cell.

The historic mission of the site was the processing of uranium ore with an alkaline-leach process. The uranium milled at the site was for private sale, but a portion was sold to the U.S. Government. The (Exxon) Ray Point Site was originally owned by Susquehanna-Western, Inc., who acquired the property in 1969 and constructed a uranium mill tailings impoundment. Susquehanna-Western, Inc. operated the mill from 1970 through 1973, processing approximately 490,000 tons of ore during this period. In 1973, Exxon Corporation purchased the Ray Point tract, including the mill and tailings impoundment. No further uranium was processed at the site. In 1979, Exxon began decommissioning the mill and completed reclamation activities in 1987.

To terminate the Texas Bureau of Radiation Control license, Exxon Mobil Corporation must conduct stateapproved reclamation ofthe site's radioactive waste. The U. S. Nuclear Regulatory Commission (NRC) will concur with the state concerning when the site will be transferred to DOE for custody and long-term care. In order for the site to be transferred to DOE, Exxon Mobil Corporation must make a one-time payment to the U.S. Treasury fully funding inspections and ongoing maintenance.


Exxon Corporation was responsible for conducting all remediation activities at this site. Contamination resulting from the uranium milling operations was consolidated into an onsite disposal cell. The 16-hectare (39-acre) cell contains approximately 27 5,400 cubic meters (360,000 cubic yards) of uranium mill tailings. The disposal cell has a 1-meter thick, low-permeability radon barrier cover and a grass surface layer for erosion control. Erosion control has been provided for all potentially vulnerable features, and the site was graded to provide positive drainage. All disturbed areas were revegetated.

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National Defense Autho.-ization Act (NDAA) Long-Term Stewardship Report

Groundwater remediation is not necessary at the (Exxon) Ray Point Site, and no groundwater monitoring is expected. Groundwater beneath the site is limited to perched zones of water with no alluvial groundwater table. This situation eliminates the potential for groundwater yield and reduces the likelihood of contaminant migration.



When Exxon completed remedial action on the tailings pond, a 2-meter (6-foot) high fence was installed around the perimeter of the property to protect the public from unauthorized intrusion onto the property. Anticipated site-wide long-term stewardship activities include restricting access through the use of the existing fence and warning signs posted along the site boundary. DOE will repair the fence and replace signs as necessary. DOE will staff a 24-hour phone line for reporting site concerns. Drilling and other intrusive activities will be prevented within site boundaries through institutional controls. DOE's Grand Junction Office will be responsible for performing long-term stewardship activities for the disposal cell at the (Exxon) Ray Point Site upon transfer to DOE.

Site records will be stored at DOE's Grand Junction Office in Colorado. The types of records that will be maintained include site characterization data, remedial action design information, the site completion report, long-term monitoring plans, annual inspection reports, and current and historic monitoring data.


Engineered Units

The site has one disposal cell containing approximately 275,400 cubic meters (360,000 cubic yards) of residual contamination. The mill tailings, soils, and construction debris within the cell are contaminated with uranium, radium, and thorium. DOE will conduct annual inspections of the 16-hectare (39-acre) disposal cell to ensure the integrity of the cap and other engineered features. Maintenance and repairs will be conducted on an asneeded basis.

Texas 12


Long-term stewardship activities at the (Exxon) Ray Point Site will be governed by several requirements in the following regulations: UMTRCA; the Atomic Energy Act of 1954, as amended; Title 10 of the Code of Federal Regulations Part 40, and the National Environmental Policy Act of 1969.


(Exxon) Ray Point Site

STAKEHOLDER INVOLVEMENT

Community interaction is expected to be minimal once the site is transferred. Copies of the annual inspection report for the (Exxon) Ray Point Site and other sites will be distributed to the local library and to any stakeholder requesting one. The site's annual inspection reports will also be published on the DOE Grand Junction Office website at www.doegjpo.com.

Cost estimates are based on the actual costs oflong-term stewardship activities at similar disposal cells currently managed by DOE's Grand Junction Office.

No groundwater monitoring is anticipated at the site based on ongoing conversations with the Texas Department of Health, as well as experience with similar sites.


Long-term stewardship costs for the (Exxon) Ray Point Site are estimated to include an initial start-up cost of $25,000 in 2001, when the site is transferred to the Grand Junction Office. Costs incurred before that time are associated with developing the initial site long-term surveillance plan and conducting activities necessary for the site's transfer to DOE. Following initial start-up, costs are associated with the ongoing monitoring and maintenance of the disposal cell. Costs are expected to remain relatively constant over the cost estimate's lifespan.

Site Long-Term Stewardship Costs (Constant Year 2000 Dollars)


FY 2000 $15,200 FY 2008 $26,300 FY 2036-2040 $127,900

FY 2001 $31,200 FY 2009 $26,300 FY 2041-2045 $127,800

FY 2002 $27,100 FY 2010 $25,700 FY 2046-2050 $127,900

FY 2003 $26,100 FY 2011-2015 $122,700 FY 2051-2055 $127,800

FY 2004 $26,400 FY 2016-2020 $119,400 FY 2056-2060 $127,900

FY 2005 $26,600 FY 2021-2025 $119,800 FY 2061-2065 $127,800

FY 2006 $26,100 FY 2026-2030 $126,600 FY 2066-2070 $127,900

FY 2007 $26,500 FY 2031-2035 $127,800

4.0 FUTURE USES

The future use of the site will be limited to monitoring and maintaining the disposal cell. Under UMTRCA provisions, access to the site will be restricted indefinitely.

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National Defense Authol"ization Act (NDAA) Long-Term Stewardship Report

For more information about the (Exxon) Ray Point Site, please contact:


Texas 14

Falls City Site

FALLS CITY SITE

1.0 SITE SUMMARY


The Falls City Site is the location of a former uranium milling site that operated from 1961 until 1973. The site contains a disposal cell for the uranium mill tailings and process-related wastes resulting from mill operations. The site is located in Kames County, Texas, approximately 74 kilometers (46 miles) southeast of San Antonio, and approximately 13 kilometers (8 miles) southwest of Falls City. The site covers 96 hectares (232 acres) and contains a 51-hectare ( 125-acre) disposal cell.

The mill used a sulfuric acid leach extraction process to produce uranium oxide from approximately 2.3 metric tons (2.5 million tons) of ore. As a result of these operations, more than 2.8 metric tons (3.1 million tons) of tailings (a sand-like, radioactive waste product) were discharged to tailings ponds, four of which were open


Major Long-Term Stewardship Activitiesgroundwater monitoring, disposal cell monitoring and maintenance; inspections; access restrictions Total Site Area- 96 hectares (232 acres) Estimated Volume of Residual Contaminantsgroundwater 4.5 million cubic meters (1.2 billion gallons); disposal cell4.4 million cubic meters (5.8 million cubic yards) Long-Term Stewardship Start-End Years- 1997-in perpetuity Average Annual Long-Term Stewardship Cost FY 2000-2006-$139,300 Landlord- U.S. Department of Energy, Grand Junction Office

pit mines excavated into the ore-bearing sandstone. The tailings ponds were nine to 11 meters (30 to 35 feet) deep and unlined, except for the naturally clayey foundation soils and sediments.

The processing site consisted of two parcels, approximately 1.6 kilometers (one mile) apart. Parcel A was fenced and encompassed 191 hectares (473 acres), including the former mill site, the mill building, five tailings piles, and a tailings pond. Parcel B encompassed 49 hectares (120 acres) and included a sixth tailings pile in the northeast area of the parcel. Windblown contamination from the tailings piles were deposited on both parcels: 121 hectares (298 acres) at Parcel A and 32 hectares (80 acres) at Parcel B. An estimated 4.4 million cubic meters (5.8 million cubic yards) of residual radioactive materials were contained within both parcels. The disposal cell is located on Parcel A.

The current mission at the Falls City Site is conducting long-term stewardship activities, including disposal cell and groundwater monitoring. The Falls City Site is subject to Title I of the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). As such, the U.S. Department of Energy's (DOE) Albuquerque Office remediated the site and the Grand Junction Office is responsible for conducting long-term stewardship activities. DOE began conducting long-term stewardship activities at the site in 1997.

The historic mission of the Falls City Site was to process uranium for sale to the U.S. Government for its national defense program. The original mill was built, owned, and operated from 1961 to 1973 by Susquehanna-Western, Inc., of San Antonio, Texas. Uranium extracted from sandstone ore was subjected to a sulfuric acid leaching process, which created approximately 2.8 metric tons (3.1 million tons) of tailings. These tailings were deposited in unlined ponds on the site. Solution Engineering, Inc., purchased the site in 1975, and conducted secondary solution mining from four tailings piles between 1978 and 1982. In 1982, the liquid in the ponds was evaporated, and the tailings were covered with soil and revegetated.

Texas 15


@ Groundwater Monitoring Well

~ Groundwater Contamination

0 0.5

Miles

Falls City Site


DOE conducted an environmental assessment of the Falls City Site and selected the remedial action alternative of consolidating the tailings onsite in a disposal cell. DOE began remedial action at the Falls City Site in 1992 and completed site remediation in 1994. The cleanup involved consolidation of seven tailings piles and additional contaminated material from 13 vicinity properties, totaling approximately 4.4 million cubic meters (5 .8 million cubic yards) of residual radioactive material, into a stabilized, 51-hectare (125-acre) disposal cell. The affected area was remediated to U.S. Environmental Protection Agency (EPA) standards. The lined disposal cell has a radon barrier cover, rock side slopes, and a grass-covered top surface layer to control erosion. The Nuclear Regulatory Commission (NRC) concurred in the DOE certification that the site was remediated to NRC-accepted design. In 1997, the site's disposal cell came under NRC's general license for the custody and long-term care of residual radioactive material disposal cells.

Groundwater beneath the Falls City Site is contaminated by past uranium ore processing activities, open pit mining, and in situ solution leaching of tailings. Open pit mining occurred on Parcels A and B of the site before milling activities began in 1961. Also, the shallow groundwater in the mined areas is of naturally poor quality because of ore bodies in the aquifer matrix. As a result, approximately 4.5 million cubic meters (1.2 billion gallons) of groundwater are contaminated. The groundwater is classified as limited use because of the naturally occurring contamination. Consequently, supplemental standards, as defined in Title 40 of the Code ofF ederal Regulations Part 192.22, have been applied and no groundwater remediation is expected.

Texas 16

Falls City Site



The Grand Junction Office is responsible for long-term monitoring and maintenance at the Falls City Site. DOE manages the site according to an NRC-approved long-term surveillance plan prepared specifically for the Falls City Site. The site is owned by the Federal Government, which controls land use within site boundaries.

DOE is responsible for conducting long-term stewardship activities, and maintaining access restrictions and institutional controls. Access is restricted by a locked gate, a wire fence, and warning signs posted every 152 meters (500 feet) along the site boundary. DOE staffs a 24-hour phone line for reporting site concerns. Drilling and other intrusive activities are prevented within site boundaries through institutional controls. DOE conducts an annual inspection to assess the integrity of the cell cover and other engineered features, and to ensure that institutional controls are effective and the site complies with applicable requirements. DOE also performs site maintenance, as necessary, including removal of woody vegetation from the rock armor and annual hay harvesting from the grass-covered areas. Groundwater is sampled and analyzed periodically, and water levels are monitored in selected wells.

The site records for the Falls City Site are kept in permanent storage at the DOE Grand Junction Office in Colorado. The types of records kept include characterization data, the remedial action design, completion report, the long-term monitoring plan, annual inspection reports, and monitoring data. Real property records are maintained at the DOE Albuquerque Operations Office.


Groundwater

Contaminated groundwater has been identified in three plumes in the shallow bedrock aquifers. Approximately 4.5 million cubic meters (1.2 billion gallons) of groundwater are contaminated with arsenic, cadmium, chromium, lead, mercury, molybdenum, net gross alpha, nitrate, radium, selenium, and uranium, which have exceeded maximum concentration limits at least twice since 1990.

No groundwater remediation is expected because

STAKEHOWER INTERACTION

Community interaction has been minimal since the remedial action was completed. Copies of the annual inspection report for the Falls City Site are distributed to the local library and any stakeholders requesting them. The report is also published on the DOE Grand Junction Office website at www.doegjpo.com.

supplemental standards, as defined in Title 40 of the Code of Federal Regulations Part 192.22, have been approved. However, groundwater must be monitored for at least five years. The groundwater protection strategy is to apply supplemental standards, as the groundwater in the uppermost aquifer is classified as 'limited use' because of its poor ambient quality and because it is not a current or potential source of drinking water. Groundwater from the uppermost aquifer contains widespread ambient contamination resulting from naturally occurring conditions and from the effects of human activity unrelated to uranium milling operations. The groundwater cannot be effectively cleaned up for drinking purposes with the treatment methods currently and reasonably employed by public water supply systems. NRC and the State of Texas concurred with the groundwater protection strategy for the disposal site in September 1992, and NRC approved the site's groundwater compliance action plan in September 1998. Monitoring will continue until2003. At that time, the need to continue monitoring will be evaluated.

Texas 17


Engineered Units

Remedial action at the site was completed in July 1994, when all radioactive materials and tailings were consolidated into an EPA-compliant, onsite disposal cell and all remediated areas were regraded and reseeded. The disposal cell contains 7,143,000 dry tons of radioactive material with a total activity of 1,277 curies of radium-226. The cell, which measures 792 meters by 671 meters (2,600 feet by 2,200 feet) at the base and rises 19 meters (62 feet) above the surrounding land, is sited at grade on a drainage divide. It occupies 51 hectares (127 acres) and is enclosed by a posted security fence. A clayey soil layer serves as a low-permeability radon barrier. A vegetated layer of top soil over a compacted soil layer covers the top of the cell. The cell was designed to promote rapid runoff of precipitation to minimize leachate. Riprap with a median diameter of 18 centimeters (seven inches) overlays a granular bedding layer on the side slopes of the cell. This 20-percent sideslope grade allows water to run off the cell sides into the surrounding six meter (20 foot) wide rock apron. The riprap protects the side slopes from erosion.

The surface conditions of the disposal cell will be monitored during annual inspections to determine whether the disposal cell and erosion protection components of the cell are performing as intended. The disposal cell at the Falls City Site was designed and constructed to last for 200 to 1,000 years. DOE's responsibility for the safety and integrity of the Falls City Site will continue in perpetuity.


In 1997, the Falls City Site came under a general license issued by NRC for custody and long-term care of residual radioactive material disposal sites (contained at Title 10 of the Code of Federal Regulations, Section 40.27). The purpose of the general license is to ensure that such sites will be cared for in a manner that protects human health and safety and the environment. The general license went into effect when NRC concurred that the site conformed to cleanup standards and formally accepted the site-specific long-term surveillance plan.

Long-term stewardship activities at the Falls City Site are governed by several other requirements in the following regulations: the Uranium Mill Tailings Radiation Control Act of 1978; the Atomic Energy Act of 1954, as amended; EPA groundwater protection standards, including Subparts B and C of Title 40 of the Code of Federal Regulations, Part 192; a cooperative agreement between DOE and the State of Texas; and the National Environmental Policy Act of 1969, as amended.


Because the site is already performing long-term stewardship activities, long-term stewardship activities are well known and are not expected to change dramatically. DOE assumes the annual groundwater monitoring frequency will be reduced to once every three years after 2003. DOE also assumes that monitoring will continue indefinitely until the disposal cell demonstrates infiltration control. It is expected that the cap will not be replaced for a minimum of 200 years.


The following table shows the estimated costs of the long-term stewardship activities at the Falls City Site. The estimated costs are based on actual costs of long-term stewardship activities at this and other sites. Contingency costs, such as cap replacement, have not been incorporated into the cost estimates.

DOE will monitor groundwater at the site annually through 2003, and then, after an evaluation of the need, will monitor likely once every three years thereafter. Fiscal Years (FY) 2001-2006 include costs for well decommissioning.

Texas 18

Falls City Site

Site U,ng•Term Stewardship Costs (Constant Year 2000 Dollars)

Year(s) Amout# Year(s) Amount Year(s) Amount

FY 2000 $82,100 FY 2008 $39,700 FY 2036-2040 $225,400

FY 2001 $173,400 FY 2009 $55,400 FY 2041-2045 $242,200

FY 2002 $181,700 FY 2010 $39,700 FY 2046-2050 $225,500

FY 2003 $165,400 FY 2011-2015 $220,800 FY 2051-2055 $242,200

FY 2004 $153,500 FY 2016-2020 $204,900 FY 2056-2060 $225,400

FY 2005 $101,100 FY 2021-2025 $225,300 FY 2061-2065 $242,200

FY 2006 $117,600 FY 2026-2030 $223,300 FY 2066-2070 $225,500

FY 2007 $39,900 FY 2031-2035 $242,200

4.0 FUTURE USES

Public access to the disposal cell will be restricted indefinitely. The site is owned by the Federal government and the future land use is not anticipated to change.

For more information about the Falls City Site, please contact:


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National Defense Authol"ization Act (NOAA) Long-Tenn Stewardship Report

Texas 20

Pantex Plant

PANTEX PLANT

1.0 SITE SUMMARY


The Pantex Plant was built by the United States Army in 1942 as a conventional bomb plant. At the end of World War II, the Plant was deactivated and the property eventually reverted to the War Assets Administration. In 1949, the entire installation was sold to Texas Tech University to be used for experimental farming, subject to recall, if necessary. Following an extensive survey of World War II ordnance plants, the Atomic Energy Commission (which later became the Department of Energy) in 1951 chose the Pantex site for expansion of its nuclear weapons assembly facilities. The Army Ordnance Corps reclaimed the site for the Atomic Energy Commission and contracted with the Silas Mason Company to rehabilitate it. From 1956 to the present, the Pantex Plant has been operated by the Mason & Hanger Corporation (MHC).


Major Long-Term Stewardship Activitiesgroundwater and soil cleanup; groundwater monitoring Total Site Area- 4,119 hectares (10,177 acres) Estimated Volume of Residual Contaminantsgroundwater 5.7 billion liters (1.5 billion gallons); playa/ditch sediment 100 hectares (250 acres); soil 250 hectares (610 acres); engineered units 16 hectares (40 acres) Portions Requiring Long-Term Stewardship as of 2006-2 Average Annual Long-Term Stewardship Cost FY 2000-2006- $1.4 million Landlord- U.S. Department of Energy, Office of Defense Programs

Located in the Texas Panhandle in Carson County north of U.S. 60, the Plant lies 27 kilometers (17 miles) northeast of downtown Amarillo. The Pantex Plant site consists of land owned and leased by the U.S. Department of Energy (DOE). DOE owns 4,119 hectares (10,177 acres), including 3,683 hectares (9,100 acres) in the main Plant area and 436 hectares (1,077 acres) at Pantex Lake, which lies approximately 4 kilometers (2.5 miles) northeast of the main Plant area. Currently, no government industrial operations are conducted at the Pantex Lake property. In addition, 2,347 hectares (5,800 acres) of land south of the main Plant area are leased from Texas Tech University for a safety and security buffer zone. The Plant is composed of several functional areas, commonly referred to as numbered zones. These include a weapons assembly/disassembly area (Zone 12), a weapons staging area (Zone 4), an area for experimental explosive development (Zone 11), a drinking water treatment plant, a sanitary wastewater treatment facility, and vehicle maintenance and administrative areas. Other functional areas include a utilities area for steam and compressed air, explosive test-firing facilities, a burning ground for thermally treating (i.e., burning) explosive materials, landfills, and Zone 10, which is currently used only for storage. Overall, there are more than 400 buildings at the Plant.

DOE's Office of Defense Programs (nuclear weapons mission) and Office of Environmental Management (environmental restoration) are jointly responsible for activities at the site. The nuclear weapons mission of the Pantex Plant, which is under the Office of Defense Programs, involves the assembling and disassembling, evaluating, repairing, and retrofitting nuclear weapons in the nations stockpile; sanitizing components from dismantled nuclear weapons; providing interim storage for plutonium pits from dismantled weapons; and developing, fabricating, and testing of chemical explosives and explosive components for nuclear weapons in support of DOE initiatives. These activities involve handling (but not processing) highly enriched uranium, plutonium, and tritium. Other activities include managing classified components that result from dismantling nuclear explosives, as well as a variety of non-radioactive toxic chemicals. Although government-owned, the Plant is a contractor-operated and managed facility since 1956.

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National Defense Authorization Act (NDAA) Long-Te1·m Stewa1·dship Report

Texas

--116'9

68

74 To Lake Pantex

(-2.5 miles)

Texas Tech Research Farm

Groundwater Contamination

0 1

Miles Pantex Plant

2

22


During more than 50 years of operation of the Pantex Plant to support defense missions, contaminants were released to the surface environment. Key contaminants include volatile and semi-volatile organic compounds, high explosives, and heavy metals. Contamination was found in the perched groundwater beneath the Zone 12 operations area, in the soil near operations areas, in previously operated landfills, and in the ditches and playas that form the Plant's drainage system. Contaminants were also found in the perched aquifer on properties neighboring the Plant to the south and southeast. A large-scale pump-and-treat system continues to operate to remove explosives, organic compounds, and chromium from the perched aquifer onsite and to reduce migration of contaminated groundwater offsite. More than 295 million liters (78 million gallons) of contaminated water has been treated, removing over 500 kilograms (1,100 lbs.) of high explosives. Interim corrective measures conducted at various areas of the Plant include:

• innovative in-situ biologic treatment and exsitu composting of high-explosivescontaminated soil;

excavation and disposal of more than 11,469 cubic meters (15,000 cubic yards) of soil contaminated with high explosives, volatile and semi-volatile organic compounds, and heavy metals; and

• removal of depleted uranium contamination, which included radiation surveys, identification, and excavation of over 1,400 cubic meters (1,830 cubic yards) of contaminated soil.

In addition, construction of more than 2.8 hectares (seven acres) of administrative landfill covers at four sites has been completed.

There are 249 identified release sites within 144 solid waste management units and areas of concern at Pantex. These sites are managed as 14 release site groupings for investigation and remediation purposes. DOE anticipates that, with the exception of perched groundwater and three-to-five soil/sediment solid waste management units, interim corrective measure cleanup

Texas

Pantex Plant

PAST ACCOMPLISHMENTS

• 42 of 43 release sites are now in steady-state and the Resource Conservation and Recovery Act (RCRA) Facility Investigation for the 43 rd site (95 th Terrace Site) is under Environmental Protection Agency (EPA) review

• Completed the Corrective Measures Study to determine which cleanup method to use for the 95th Terrace Site

PLANNED ACCOMPLISHMENTS

• Complete the Corrective Measures Implementation Design which specifies construction details for cleanup of the 95 th Terrace Site

• Continue groundwater treatment and monitoring activities, including well monitoring and maintenance, preparing regulatory reports, and groundwater interceptor well design

STAKEHOLDER INTERACTION

Public participation associated with the Pantex Environmental Restoration Program includes monthly meetings with the Pantex Plant Citizen's Advisory Board; quarterly public meetings that are open to the community; and various presentations provided to local special interest groups, such as the League of Women Voters, the Pantex Plant Environmental Task Force, and owners of land adjacent to the Pantex Plant. An electronic reading room has been established at a local community college, in addition to the Administrative Record file located at Pantex, which allows the public access to technical documents that provide investigation and assessment results that support decisions regarding corrective actions at Pantex. Public notice and comment periods are required for review of corrective measures and preferred alternative selection; public notice is also required once a final preferred corrective action design is approved. In addition, press releases, public tours, and videos are provided to update the public on the status.

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National Defense Authorization Act (NDAA) Long· Term Stewardship Report

results will meet regulatory closure requirements. For those solid waste management units not closed by interim corrective measures, final corrective action design and construction activities to implement preferred remediation alternatives will be conducted. Interim corrective measures for the perched aquifer will continue through 2004, when completion of construction activities for the final preferred remediation alternative is scheduled to occur. Completion of final preferred alternative construction activities for soil/sediment sites that require corrective action is also scheduled to be completed by 2004.

2.0 SITE-WIDE LONG-TERM STEWARDSHIP DISCUSSION

2.1 Site-Wide Long-Term Activities

As the site landlord, DOE Defense Programs has stewardship responsibilities for all Pantex facilities and will determine their future use after the current cleanup end-states are achieved. All release sites at Pantex will be remediated to achieve closure designation in accordance with the cleanup levels specified by the Texas Risk Reduction Standards regulations and associated site-specific guidance for soils and groundwater cleanup. It is anticipated that groundwater

LONG-TERM STEWARDSHIP GOALS

Long-term stewardship goals at Pantex include restoring impacted groundwater to beneficial use quality and ensuring soil/sediment sites requiring post closure care are managed in a manner that prevents adverse effects to human health and the environment.

pump-and-treat operations will continue through 2055 to effectively treat groundwater contamination; however, the long-term efficiency and capability of the groundwater extraction and treatment system is uncertain, and additional time could be required to fully achieve groundwater remediation objectives. The assumed date for the project end-state will be evaluated periodically, as additional operational effectiveness information becomes available. Further, regulatory requirements for landfill/soil/sediment cover maintenance, and groundwater monitoring and treatment operations will be negotiated with the regulatory agency periodically.

2.1.1 Institutional and Engineered Controls

Institutional and engineered controls for the Pantex Plant will vary depending on the level of residual contamination remaining at the release site. These controls may include, as appropriate, deed recordation and land use restrictions according to residual contaminant levels remaining and cleanup levels achieved; in-situ containment by use of landfill covers/caps and ditch liners; fencing; and administrative controls, such as operating procedures that limit exposure to environmental media with residual contamination.

2.1.2 Record-Keeping Activities

Record-keeping activities for the Pantex Plant Environmental Restoration Program are directed under Title 42 United States Code (42 U.S.C.) 9613, Section 113(k) Administrative Record and Public Participation; Title 40 Code of Federal Regulations ( 40 CFR) Part 300, Subpart I - Administrative Record for Selection of Response Action; 36 CPR Chapter XII, National Archives and Records Administration Requirements (Subchapter B), and record-keeping requirements stipulated in the Pantex Plant's Resource Conservation and Recovery Act (RCRA) Hazardous Waste Operating Permit. Governing documents include DOE Orders 1324.2A, Records Disposition; 5500.7 A, Vital Records Protection Program; 1325.5A, Records Management Program; and various Pantex Plant records manuals, directives, standards and internal operating procedures. These regulatory drivers and governing documents, along with guidance documents, provide for what records must be maintained, where they must be maintained, the duration of document maintenance, and final disposition requirements. In general, operating records, investigation, assessment, remediation, monitoring, interaction documentation between Pantex and regulatory agencies, and public participation records will be kept onsite at the Pantex Plant as part of an Administrative Records file.

Texas 24

Pantex Plant

The Pantex Plant is on the National Priorities List and, therefore, the Administrative Records file at Pantex will maintain official records that relate to response/remedial action decisions for environmental corrective action for a period of time identified as the Statute of Limitations time period specified for sites on the National Priorities List. General DOE record-keeping requirements stipulate that unscheduled records, such as environmental records, must be maintained for 75 years. Records are microfilmed for long-term retrieval purposes. DOE maintains a public reading room for the Pantex Plant at Amarillo College, located in Amarillo, Texas. Documents that are generated and placed in the Pantex Administrative Records file are provided in hard copy or electronic form to Amarillo College for public access purposes.


The possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided due to the fact that not all investigation and cleanup reports have been reviewed and approved by the applicable regulatory agencies. In addition, corrective measures studies/designs approval and subsequent final corrective action construction activities are dependent on final approval of the investigations. Additional investigations have the potential to identify conditions requiring revision of previous recommendations or future corrective actions planned. Input received from regulatory authorities and/or the public on proposed final corrective actions may result in final corrective action alternative selections differing from those currently anticipated.


Site-wide assessments and environmental monitoring programs have been and are being conducted. The first environmental characterization began in 1981 in order to prepare an Environmental Impact Statement. This activity was followed by a multi-phased Comprehensive Environmental Restoration Program assessment from 1985 through 1986. A 1986 environmental survey found soil contamination in various locations at the Pantex Plant. A RCRA Facility Assessment, completed in 1989, identified solid waste management units that required characterization to ensure potential threats to human health and the environment were identified and minimized. There are currently 14 groupings of solid waste management units based on suspected types of contaminants and potential source areas.

Restoration activities at the Pantex Plant are regulated jointly by the Texas Natural Resources Conservation Commission (TNRCC) and the U.S. Environmental Protection Agency (EPA), and the agencies have signed a memorandum of understanding for activities at Federal facilities. As a permitted hazardous waste facility, the Pantex Plant is regulated under RCRA, and the TNRCC has been granted authority to administer the RCRA Program in Texas. An Administrative Order on Consent was signed by EPA and DOE in 1990, outlining the remedial response actions under RCRA for the Pantex Plant. In May 1994, the Pantex Plant was added to the National Priorities List, thereby subjecting Pantex to Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements. EPA and TNRCC have allowed an integration of RCRA and CERCLA processes to continue closure of contaminated sites. The Pantex Plant is still on theN ational Priorities List.

Closure of release sites with residual contamination is classified in the State of Texas by contaminant levels that correspond to one of three Risk Reduction Standards. Risk Reduction Standard 1 closures represent release sites with no residual contamination remaining above established background levels. Risk Reduction Standard 2 closures represent release sites with residual contamination that is protective of human health and the environment without implementation of post-closure care. Risk Reduction Standard 3 closures represent release sites with residual contamination at levels that require post-closure care in the form of administrative, and/or institutional, and/or engineering controls.

Texas 25

' National Defense Authorization Act (NDAA) Long-Term Stewardship Report

2.4 Estimated Site-Wide Long-Term Stewardship Costs

Costs for long-term stewardship at Pantex consist primarily of groundwater corrective actions and monitoring. Groundwater corrective actions may consist of both pump-and-treat and in-situ treatment methodologies. Costs associated with long-term groundwater treatment, in addition to actual equipment maintenance, system augmentation, technical oversight, utility costs, and infrastructure costs, include both regulatory-required corrective action and compliance monitoring. Corrective action and compliance monitoring costs include personnel costs to maintain equipment and collect samples, system operation costs, and analytical costs to evaluate contaminant reduction. It is estimated that groundwater treatment and corrective action monitoring will continue at Pantex through Fiscal Year 2055. The time period for conducting groundwater compliance monitoring will be negotiated between DOE and the TNRCC but is anticipated to continue indefinitely (for purposes of this report, through Fiscal Year (FY) 2070). Long-term stewardship costs for Risk Reduction Standard 3 closures of soil/sediment sites include engineered unit maintenance and, as needed, replacement. Also included are the technical oversight costs necessary to evaluate the effectiveness of the implemented corrective action and costs necessary to maintain administrative controls. It is estimated that approximately 5 percent of the total long-term stewardship costs at Pantex will be a result of maintaining administrative controls for release sites closed under Risk Reduction Standard 2. The remaining costs are attributable to meeting cleanup objectives, maintaining, and monitoring the cleanup of sites closed under Risk Reduction Standard 3.

Site Long-Term Stewardship Costs (Constant Year ZOIJ,() Dollars)


FY 2000 $0 FY 2008 $1,381,000 FY 2036-2040 $6,374,000

FY 2001 $0 FY 2009 $1,411,000 FY 2041-2045 $6,945,000

FY 2002 $0 FY 2010 $1,624,000 FY 2046-2050 $7,566,000

FY 2003 $1,496,000 FY 2011-2015 $8,240,000 FY 2051-2055 $8,547,000

FY 2004 $1,418,000 FY 2016-2020 $9,351,000 FY 2056-2060 $4,195,000

FY 2005 $1,317,000 FY 2021-2025 $10,463,000 FY 2061-2065 $4,843,000

FY 2006 $1,374,000 FY 2026-2030 $11,337,000 FY 2066-2070 $5,060,000

FY 2007 $1,471,000 FY 2031-2035 $12,745,000

3.0 PORTION OVERVIEW

The regulatory regime in Texas identifies three closure standards (Risk Reduction Standards) for release sites depending on residual contamination remaining in environmental media, subsequent risk to human health and the environment resulting from the residual contamination, and the controls required to maintain acceptable risk levels. Therefore, for the purpose of this document, long-term stewardship activities are discussed in terms of "portions," which correspond to Risk Reduction Standard closures that have long-term stewardship requirements. Portions have been further subdivided into the type of environmental media or units (i.e. soil, groundwater, surface water/sediment, engineered units) that are subject to closure under the Risk Reduction Standards.

Release sites approved for closure under Risk Reduction Standard 1 do not require administrative, institutional, engineered controls, or monitoring. Release sites approved for closure under Risk Reduction Standard 2 require long-term stewardship in the form of deed recordation that restricts use of the property to activities that correspond to the cleanup levels achieved (residential vs. non-residential). Release sites at Pantex closed under

Texas 26

Pantex Plant

Risk Reduction Standard 2 will primarily be cleaned up to levels that restrict, by implementation of deed restrictions, the future use of the site to activities that are allowed for property zoned for industrial use (nonresidential). It is currently planned that contaminated perched groundwater within the Pantex Plant property boundaries will be cleaned up to approved Risk Reduction Standard 3 residual concentration levels (alternate concentration levels) that result in contaminant concentrations that meet Risk Reduction Standard 2 residential cleanup levels at the property boundary. It is currently planned that cleanup levels for offsite perched groundwater will achieve Risk Reduction Standard 2 levels for residential use; however, final cleanup levels achieved will depend on technical limitations for remediating the groundwater and negotiations with offsite landowners. Release sites at Pantex recommended for closure under Risk Reduction Standard 2 include certain soils, sediments, and surface water solid waste management units.

Release sites approved for closure under Risk Reduction Standard 3 require post-closure care in the form of continued remedial actions until approved cleanup levels are met and/or it can be demonstrated that residual contamination does not represent risk to human health and the environment above approved cleanup levels in the absence of post-closure care. Release sites closed under Risk Reduction Standard 3 also require corrective action monitoring and maintenance until the post-closure care period is complete. Release sites closed under Risk Reduction Standard 3 will have institutional and/or engineered controls that limit the future use of the release site on a site-specific basis. Generally, when closed under Risk Reduction Standard 3, the future use of the release site will be restricted to activities allowed in areas zoned for industrial activities. However, in some Risk Reduction Standard 3 closures, post-closure care requirements and residual contamination will limit future use of the release site to activities associated with monitoring and maintenance of the engineered control or activities allowed by institutionalized access control. Release sites that are anticipated to require the complete RCRA corrective action process (Baseline Risk Assessment, Corrective Measure Study, Corrective Measure Design, and Corrective Measure Construction) to achieve closure under Risk Reduction Standard 3 include several inactive landfill solid waste management units, several solid waste management units that consist of ditches previously used for waste water transport, perched groundwater, and one solid waste management unit associated with previous discharges of high explosives waste water.

The primary contaminants at both Risk Reduction Standard 2 and Risk Reduction Standard 3 sites include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds, including trichloroethylene, chrysene, acetone, benzo(a)pyrene and benzo(a)anthracene. Current estimates indicate that 5. 7 billion liters ( 1.5 billion gallons) of contaminated perched groundwater require treatment and approximately 364 hectares (900 acres) of soil/sediments/surface water sites will be closed under Risk Reduction Standard 2 and Risk Reduction Standard 3. Planned engineered units include ditch liners, engineered soil coverings, and a groundwater treatment and processing system and facility. All final preferred alternative corrective measures construction activities are scheduled to be completed by 2004.

The tables on the following pages provide a correlation of the proposed Risk Reduction Standard closure to each solid waste management unit and area of concern that comprise the operable unit groupings at Pantex.

Portion Long-Term Stewardship Start-Year Long-Term Stewardship End-Year

Risk Reduction 2 2003 in perpetuity

Risk Reduction 3 2003 in perpetuity

Texas 27


AL- PX- 01 Burning Ground SWMUs 14 to 27- Explosive Bum Pads SWMUs 37 to 44- Landfills SWMU 47- Chemical Bum/ Evaporation Pits

SWMU - Demonstration Facilities X AL- PX- 02 High Priority SWMU 11 - Building FS- 16 -Surface Impondment in Zone 5 X Potential Release Sites SWMU 13 - Former Solar Evaporation Pond (Building 11- 51) X

SWMU 109- Concrete Sump (Building 12- 68) X SWMU 136- Subsurface Leaching Beds (Building 12- 59) X SWMU 139- Photo Processing Leaching Bed (Building FS- 10) X AOC 12 Building 12- 5D Paint Shop Area X Unassigned - Firing Site 1 (FS- 1) - Unlined Landfill X Firing Site 20 (FS- 20) - Equipment X

Site 24 -Concrete X AL- PX- 03 Former Cooling AOC 13- Former Cooling Tower in Zone 12 X Tower

SWMU 140- Old Sewage Treatment Plant Sludge Beds X

AOC 11 - Fire Training Area Burn Pits X

Site-Wide Groundwater X Groundwater AL- PX- 07 Landfills Construction Debris Landfills:

SWMU 54 - Landfill 3 X SWMU 55- Landfill4 X SWMU 56 - Landfill 5 X SWMU 57 - Landfill 6 X SWMU 58 - Landfill 7 X SWMU 59 - Landfill 8 X SWMU 60 - Landfill 9 X SWMU 61 -Landfill 10 X SWMU 62 - Landfill II X SWMU 63- Landfill12 X SWMU 64 - Landfill 13 X SWMU 66- Landfill 15 X General Purpose General Sanitary Landfills: SWMU 68a - Original Landfill X SWMU 68b - Landfill 1 X SWMU 68c - Landfill 2 X SWMU68d- Landfill X

AL- PX- 08 Ditches and Playas SWMU 1 - Building 12- 17 - Drainage Ditch X SWMU 2- Building 12-43- Drainage Ditch X SWMU 3- Building 11-44- Drainage Ditch X SWMU 4 - Building 11- 50 - Drainage Ditch X SWMU 5-01- Buildings 12-5 and 12- 5B Ditches X SWMU 5-02- Buildings 12-51, 12-67, and 12- 110 Ditches X SWMU 5-03- Buildings 12-9, 12- 10, 12- 18, and 12-68 Ditches X SWMU 5-04- Buildings 12- 19 and 12-73 Ditches X SWMU 5-05- Buildings 12-21 and 12-24 Ditches X SWMU 5-06- Buildings 12- 44E and 12- 81 Ditches X SWMU 5-07- Building 12-41 Ditches X SWMU 5- 08 -Building 11- 36 Ditches X SWMU 5- 09 - Buildings 11- 17, 11- 20, and Pond 11- 51 Ditches X SWMU 5- 10 - Ditches Near the Old Sewage Treatment Plant X SWMU 5- II - Zone 11 Main Perimeter Ditch X SWMU 5- 12- Zone 12 Main Perimeter Ditch X SWMU 5- 13 - Three Main Ditches to Playa I X SWMU 5- 14- Main Ditches to Playa 2 X SWMU 5- 15 - Main Ditches to Playa 4 X SWMU 6 - Playa 1 X SWMU 7 - Playa 2 X SWMU 8 - Playa 3 X SWMU 9 - Playa 4 X SWMU 10 - Pantex Lake X

Texas 28

Pantex Plant

. : . ' ()peril/Jle Unit . i ·Solid W4$te Managemellt Units (~~M(lsMrem: pfConcem (AOCs), and RRS RRS RRS3 . ···, . ·' Other PQtential Release Sites •. .··· .... J 2

AL- PX- 09 Firing Sites SWMU 70 - Firing Site 5 X SWMU 71 - Firing Site 6 X SWMU 73- Firing Site 15 X SWMU 69- Firing Site 4 (Active) N/A N/A N/A SWMU 72- Firing Site 10 (Active) N/A N/A N/A SWMU 74- Firing Site 21 (Active) N/A N/A N/A SWMU 75 -Firing Site 22 (Active) N/A N/A N/A

AL-PX-10 Leaking USTs at AOC 6- Gasoline Leaks at Buildings 12-35 and 16-1 N/A N/A N/A Buildings 12-35 and 16-1

AL- PX- 11 Miscellaneous High SWMU 53 - Temporary HE Burning Grounds X Explosives/ Rad Sites SWMU 82- Nuclear Weapon Accident Residue Storage X

SWMU 135- Leaching Bed Building 12- 44E X Zone 10 TNT Settling Pits: SWMU 144 Building 10- 13 X SWMU 145 Building 10- 17 X SWMU 146 Building 10-26 X Zone 11 TNT Settling Pits: SWMU 147 Building 11- 13 X SWMU 148 Building 11- 17 X SWMU 149 Building 11- 26 X SWMU 150 Building 11- 12 X Building 11- 44- Wastewater Treatment Unit: SWMU 117 HE Settling Tank X SWMU 118 Equalization Basin X SWMU 119a HE Filters X SWMU 120a Carbon Filters X Building 12- 43 -Wastewater Treatment Unit: SWMU 119b HE Filters X SWMU 120b Carbon Filters X SWMU 121 HE Settling Tank X SWMU 122 Equalization Basin X SWMU !22b Building 12- 24N & Building 12-43 Upland Soils X SWMU 123 Concrete Sump X

AL- PX- 12 Miscellaneous SWMU 84- Building 10- 9, Scrap Salvage & Storage Yard X Chemical Spills/ Release Sites SWMU 103- Former Battery Storage Area, Building 12- 81 X

SWMU 143- Former Waste Drum Storage Areas, Buildings 10-9&10-7 X AOC 1 -Transformer Leak, Building 11- 14A X AOC 3 - Former Boiler House Areas Zone 10- AOC 3a X Zone 11- AOC 3b X AOC S- Electrical Equipment Bone Yard X AOC 7 - Sulfuric Acid Spills: Building 11- 36- AOC 7a X Building 12- 4- AOC 7b X Building 12- 64- AOC 7c X AOC 8 - Solvent Leaks: Pad 11- 2 - AOC Sa X Pad 11-13-AOCSb X Building 11- 17 - AOC 8c X Building 11- 22 -AOC 8d X Building 11- 36- AOC 8e X AOC 10- Pesticide Rinse Areas: Building 12- 43A- AOC lOa X Building 12-51- AOC lOb X AOC 14- Battery Storage Area, Building 12- 18 X AOC 15- DDT Release at Building 12- 35 X Unassigned - Capacitor Bank Rupture X Unassigned- Evaporation Pit East of Bay 3, Building 11-20 X Unassigned- Evap. Pit South of Bay 11 & West of Bay 6, Bldg 11- 20 X Unassigned-Form. Leaching Bed N. of Bldg 11-50 & W. of Bldg 11-36 X SWMU 113 -Overflow From 11-36 Collection System/Sump X AOC 2 - Main Electrical SYstem Subsystem X

Texas 29

National Defense Authorization Act (NDAA) Long-Term Stewardship Repot·t

Operable Unit Solid Waste Managemmt U11its (SWMUs),Are,as.of:'Jonce,rn(AOCs), ~ RRS RRS RRS3 I Other Potential Release Sit:es .· .. ·· · '· · ·. · .• 1 2

AL- PX- 13 Supplemental SVS I - Denuded Area near Playa I X Verification Sites SVS 2 -Parallel Depressions Near Building I I- 26 X

SVS 3 (SWMU 67) -Carbon Black Burial Area near Building 10- 7 X SVS 4- Old Pistol Range (Active) N/A N/A N/A SVS 5- Zone 11 Landfill East of Pad 11- 13 X SVS 6 (SWMU 65)- Unnumbered Zone 7 Landfills X SVS 7 - Igloo Demolition Debris Landfills, Zone 4 & Zone 5 X

AL-PX-14 USTs at Other UST #9- Building 12-!7E N/A N/A N/A Locations UST #7- Building 12-5B N/A N/A N/A

UST #38- Building 12-84A N/A N/A N/A SWMU 133- Waste Oil Tank at Building 16-1 N/A N/A N/A

3.1 Risk Reduction Standard 2 Sites Portion

Risk Reduction Standard 2 Sites portion at Pantex comprises a total of approximately 280 hectares (700 acres). The Portion size does not include surface area covering Risk Reduction Standard 2 areas of the perched aquifer (estimated at 320 hectares, 800 acres). Of the 249 identified release sites at Pantex that correspond to solid waste management units and areas of concern, approximately 150 of the sites, including soils, sediments, off site impacted perched groundwater, and surface water sites, have been or will be recommended for closure under Risk Reduction Standard 2. Release sites approved for closure under Risk Reduction Standard 2 are sites with residual contaminant levels that are protective of human health and the environment and that allow for continued use of the site, consistent with deed restrictions imposed. Pantex has a site-specific Risk Reduction Standard

RISK REDUCTION STANDARD 2 SITES PORTION HIGHLIGHTS

Major Long-Term Stewardship Activities- deed recordation that restricts use of the property/media to activities that correspond to the cleanup levels achieved (residential vs. non-residential) Portion Size- 280 hectares (700 acres) Estimated Volume of Residual Contamination- soil 200 surface hectares (500 acres); groundwater 1,890 million liters (500 million gallons); sediment 81 surface hectares (200 acres) Long-Term Stewardship Start-End Years- 2003-indefinitely Average Annual Long-Term Stewardship Costs FY 2003-2006-

closure guidance document that has been approved by the TNRCC. This document is used to establish cleanup levels for individual contaminants and provides the statistical and confirmation framework to ensure cleanup levels are met.

For the general purpose of release site closure under Risk Reduction Standard 2, cleanup levels for individual contaminants are represented by Texas or federal promulgated heath-based standards, or, when these are not available or do not provide appropriate protection for human health or the environment, cleanup levels (identified as medium specific concentrations) must be developed. The medium specific concentrations address a single contaminant in a medium and consider one or more exposure pathways-- specifically, water ingestion and soil ingestion with inhalation of volatiles and particulates. Where a contaminant in one medium has the potential to contaminate another medium, additional numeric criteria are developed as cleanup levels. The cleanup levels must correspond to contaminant concentrations that represent: 1) upper bound lifetime cancer risk of 0.000001 for class A and B carcinogens and 0.00001 for class C carcinogens; and 2) for systemic toxicants, exposure cannot result in any deleterious effect.

Additional medium-specific requirements for soil/sediments include the following:

Texas

1) Residual contamination must not exhibit the hazardous waste characteristic of ignitability, reactivity or corrosivity;

30

----~9

Playa 3

Texas Tech Research Farm

- Active Site Locations --• Risk Reduction Standard 2 Sites

Texas

~ Soil Contamination

0.=-~--~2,~00~0~~~~-000 Feet

Risk Reduction Standard 2 Portion

Pantex Plant

Lake P~ntex \ (~2.5 miles)

31


2) The sum of volatile organic compounds in vapor phase must not exceed 1,000 parts per million by weight or volume;

3) For closure to residential use criteria, residual contaminant concentrations throughout the soil column shall not exceed the lower of the soil medium-specific concentration, based upon residential human ingestion of soil and inhalation of particulates and volatiles and the residential soil-to-groundwater crossmedia protection concentration. The residential soil-to-groundwater cross-media protection concentration is equivalent to one hundred times the residential groundwater cleanup level or a concentration in soil that does not produce a leachate in excess of maximum contaminant levels or medium specific concentrations;

4) For closure to non-residential use criteria, contaminant concentrations shall not exceed one hundred times the non-residential groundwater cleanup level or a concentration in soil that does not produce a leachate in excess of the non-residential groundwater cleanup level.

Additional medium-specific concentration cleanup levels for groundwater include the following:

1) For residential exposure, promulgated Safe Drinking Water Act maximum contaminant levels. If maximum contaminant levels do not exist, cleanup levels are calculated medium-specific concentrations for human ingestion with no resulting adverse affect ;

2) For non-residential exposure, maximum contaminant levels, or if maximum contaminant levels do not exist, calculated medium specific concentration levels that have been multiplied by 3.36 for carcinogens and 2.8 for systemic toxicants.

Pantex has a site-specific Risk Reduction Standard closure guidance document that has been approved by the TNRCC. This document is used to establish cleanup levels for individual contaminants and provides the statistical and confirmation framework to ensure cleanup levels are met. However, due to the fact that not all investigation and cleanup reports have been reviewed and approved by the TNRCC, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Additional investigations have the potential to identify conditions requiring revision of previous recommendations. In addition, ultimate cleanup goals for offsite property that is not owned by the DOE are subject to negotiation with offsite landowners.

Institutional and Engineered Controls

Deed recordation, which limits the use of the land that is closed under Risk Reduction Standard 2, is the applicable institutional control. Implementing mechanisms to ensure that deed restrictions are adhered to include management controls provided in Plant Standards, Directives, and Operating Procedures for activities conducted on land owned by the DOE. The placement of deed restrictions on property not owned by DOE will require negotiation with the landowners. It is anticipated that, in some cases, fencing, signs, and access restriction will accompany deed restriction of Risk Reduction Standard 2 sites to ensure land use is consistent with covenant restrictions.

3.1.1 Soil

Releases affecting soil at Pantex have resulted from past production operations associated with fabrication of chemical explosive components for nuclear weapons, nuclear weapon assembly/disassembly, weapon modification and repair, surveillance testing of weapon components, and treatment/disposal of chemical explosives and non-radioactive components. Media contamination from these operations occurred by discharging

Texas 32

Pantex Plant

wastewater to unlined ditches, onsite treatment/disposal of high explosives contaminated solvents, spills and leaks of raw and produced materials, onsite landfilling of solid wastes, and onsite discharge of wastewater to playa lakes. The primary contaminants at Risk Reduction Standard 2 soil sites include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds, including trichloroethylene, chrysene, acetone, benzo(a)pyrene and benzo(a)anthracene. It is estimated that approximately 200 surface hectares (500 acres) of soil media will be closed under Risk Reduction Standard 2.

Soil sites closed under Risk Reduction Standard 2 include soils less than 0.6 meter (two feet) below surface elevation (surface soils) and greater than 0.6 meter (two feet) below surface elevation (subsurface soils). Risk Reduction Standard 2 sites are determined to be protective of human health and the environment as long as land use and activity restrictions match deed restrictions.

Long-Term Stewardship Activities

Long-term stewardship goals for soil sites closed under Risk Reduction Standard 2 are to ensure land use is consistent with restrictions imposed by deed recordations and to ensure controls are maintained that comply with closure requirements. In general, Risk Reduction Standard 2 closures of sites will be conducted to meet nonresidential cleanup requirements. Activities conducted to meet these goals may include implementation of procedural limitations for site use, construction and maintenance of signs, fencing, etc., and administrative limitations of site operations.

3.1.2 Groundwater

The estimated volume of off site groundwater that requires treatment to meet Risk Reduction Standard 2 cleanup levels is approximately 1,890 million liters (500 million gallons). Approximately 320 hectares (800 acres) is the estimated total offsite surface area below which perched groundwater requires cleanup. Releases affecting perched groundwater at Pantex have resulted from past production operations associated with fabrication of chemical explosive components for nuclear weapons, nuclear weapon assembly/disassembly, weapon modification and repair, surveillance testing of weapon components, and treatment/disposal of chemical explosives and non-radioactive components. Perched groundwater contamination from these operations is believed to have occurred primarily by discharging wastewater to unlined ditches, on-site treatment/disposal of high explosives contaminated solvents, and spills and leaks of raw and produced materials. The primary contaminants in off site perched groundwater are the high explosives RDX and HMX. The primary contaminants in onsite perched groundwater are high explosives (primarily RDX, TNT, and HMX), heavy metals (primarily chromium), and volatile organic compounds (primarily trichloroethylene). It is anticipated that onsite perched groundwater will be closed under Risk Reduction Standard 3 while offsite perched groundwater will be closed under Risk Reduction Standard 2.

The two principal aquifers beneath the Pantex Plant and adjacent areas are the Ogallala aquifer and the underlying Dockum Group aquifer. Approximately 140 meters (450 feet) of unsaturated vadose zone is present between the ground surface and the Ogallala aquifer. A perched water zone (perched aquifer) is present in the middle of the Ogallala formation at a depth of approximately 82 meters (270 feet) below ground surface and is generally continuous beneath the main facilities of the Pantex Plant and some adjacent areas. The saturated thickness in this perched aquifer ranges from a few feet at the southern margin to greater than 15 meters (50 feet). The main Ogallala aquifer is unconfined and lies beneath the perched aquifer. The main Ogallala aquifer, the saturated portion of the Ogallala formation, is the principal water supply of the Southern High Plains. The regional groundwater flow in the main Ogallala aquifer beneath most of the Southern High Plains is to the southeast. Groundwater flow in the Ogallala aquifer beneath the Pantex Plant and adjacent area is toward the north-northeast. The north-north-east flow is controlled by the east -northeast slope of the Southern High Plains and the Canadian River Valley to the north and also by a large cone of depression surrounding the City of

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National Defense Authorization Act (NDAA) Long-Tenn Stewardship Report

Amarillo-Carson County Well Field, located immediately north of the Pantex Plant.

Groundwater contamination at Pantex is primarily restricted to the perched aquifer. Detection of contaminants above drinking water standards have recently been identified in samples collected from Ogallala aquifer monitoring wells near the northwest boundary of the Pantex Plant and in an Ogallala well southeast of the Plant. Investigation of the nature and extent of the contamination in the Ogallala aquifer is currently being conducted at Pantex. The Dockum Group aquifer lies under the Ogallala aquifer beneath the Pantex Plant and to the south. No detailed information is available on the potentiometric surface of the Dockum Group aquifer for the Pantex Plant area.

Specific Risk Reduction Standard 2 residential remedial action objectives for the primary contaminants in perched groundwater at Pantex are 0.00774 milligrams per liter for RDX; 0.018 milligrams per liter for TNT; 1.825 milligrams per liter for HMX; and 0.005 milligrams per liter for trichloroethylene. Current fate and transport modeling does not indicate that chromium contamination in the perched aquifer will migrate off-site; therefore, a Risk Reduction Standard 3 alternate concentration level will be developed for this contaminant. Ultimate cleanup goals for offsite property that is not owned by DOE are subject to negotiation with offsite landowners. Therefore, the overall level of confidence for cleanup of offsite perched groundwater to Risk Reduction Standard 2 residential levels is low due to the fact that ultimate cleanup requirements are subject to negotiation and technical feasibility.

Long~ Term Stewardship Activities

Long-term stewardship goals for closure of perched groundwater under Risk Reduction Standard 2 are to protect the Ogallala aquifer and restore perched groundwater to beneficial use. Activities necessary to obtain these goals include implementation of corrective actions, which consist of both pump-and-treat and in-situ treatment methodologies to reduce contaminant concentration levels to those that allow for offsite unrestricted perched groundwater residential use, groundwater monitoring, and deed recordation.

3.1.3 Surface Water/Sediment

DOE estimates that approximately 81 surface hectares (200 acres) of sediment will be closed under Risk Reduction Standard 2. A volume estimation of surface water/sediment with residual contamination that will be closed under Risk Reduction Standard 2 does not provide a useful tool because use restrictions of residually contaminated environmental media are identified and implemented by surface surveys. The primary contaminants at Risk Reduction Standard 2 surface water/sediment sites include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds including trichloroethylene, chrysene, acetone, benzo(a)pyrene and benzo(a)anthracene. The primary reason for residual contamination of surface water/sediments is the historical practice of discharging untreated wastewater. Untreated wastewater is no longer discharged to ditches or surface water bodies (playas).

Surface water/sediment sites recommended for closure under Risk Reduction Standard 2 include several surface water sites (playas) and primarily ditch sediments that are less than 0.6 meter (two feet) below surface elevation (surface sediments). Sediments greater than 0.6 meter (two feet) below surface elevation are categorized as subsurface soils. Although the playas at Pantex are ephemeral water bodies often containing water only seasonally, many playas meet the soils, hydrology, and vegetation criteria for classification as jurisdictional wetlands. Sediments at Pantex are associated primarily with a network of constructed ditches, including some that direct surface water flow away from buildings within interior zones of the Pantex Plant.

For release sites associated with surface water/sediments at Pantex that have been recommended for closure under Risk Reduction Standard 2, the level of confidence for attaining regulatory approval is medium. Pantex

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Pantex Plant

has a site-specific Risk Reduction Standard closure guidance document that has been approved by the TNRCC. This document is used to establish cleanup levels for individual contaminants and provides the statistical and confirmation framework to ensure cleanup levels are met. Because of the fact that not all investigation and cleanup reports have been reviewed and approved by the TNRCC, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Additional investigations have the potential to identify conditions requiring revision of previous recommendations.


Long-term stewardship goals for surface water/sediment sites closed under Risk Reduction Standard 2 are to ensure land use is consistent with restrictions imposed by deed recordations and to ensure controls are maintained that comply with closure requirements. In general, Risk Reduction Standard 2 closures of sites will be conducted to meet non-residential cleanup requirements. Activities conducted to meet these goals may include implementation of procedural limitations for site use, construction and maintenance of signs, fencing, etc., and administrative oversight of site operations.

3.1.4 Estimated Long-Term Stewardship Costs for Risk Reduction Standard 2 Sites Portion

The table below identifies the estimated costs for performing long-term stewardship activities at the Risk Reduction Standard 2 Sites portion. Costs to implement and maintain Risk Reduction Standard 2 closures represent about five percent of the total long-term stewardship costs for release site closures at Pantex.

Long-Term Stewardship Costs (Constant Year 2000 Dollars)

FY 2000- FY 2011- PY 2021· FY 2031-FY 2020 FY 2020··· FY 2030 FY 2040

$576,000 $880,000 $1,090,000 $956,000

3.2 Risk Reduction Standard 3 Sites Portion

The Risk Reduction Standard 3 Sites portion comprises a total of 81 hectares (200 acres). This size represents the estimated total area of all sites recommended for closure under Risk Reduction Standard 3 but does not include the estimated total onsite surface area below which perched groundwater requires cleanup (557 hectares, 1,376 acres). The volume of perched groundwater that is anticipated to be closed under Risk Reduction Standard 3 is approximately 3.8 billion liters (one billion gallons). Of the 249 identified release sites at Pantex that correspond to solid waste management units and areas of concern, approximately 50 of the sites, including soils (landfills, historical spill/discharge, historical waste processing sites), sediments (ditches), and onsite perched groundwater, will be recommended for closure under Risk Reduction Standard 3. It is currently anticipated that approximately 16 hectares (40 acres) of the total 81 hectares (200 acres) that will be recommended for

FY 2041· FY 2051- FY 2061- Estimated FY 2050 FY 2060 FY 2070 Total

$726,000 $637,000 $495,000 $5,360,000

RISK REDUCTION STANDARD 3 SITES PORTION HIGHLIGHTS

Major Long-Term Stewardship Activities- deed recordation; maintaining administrative; institutional and/or engineered controls Portion Size- approximately 81 hectares (200 acres) of soil/sediment solid waste management units, of which approximately 16 hectares (40 acres) will be comprised of engineered corrective action units such as landfill caps/soil covers and ditch liners Estimated Volume of Residual Contaminants- soil45 surface hectares (110 acres); onsite perched groundwater 3.8 billion liters (one billion gallons); sediment 20 surface hectares (50 acres); engineered units 16 surface hectares (40 acres) Long-Term Stewardship Start-End Years - 2003-indefinitely Average Annual Long-Term Stewardship Costs FY 2003-2006- $5,324,000

closure under Risk Reduction Standard 3 will require engineered controls (caps/covers, liners, etc.).

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National Defense Authol"ization Act (NDAA) Long-Term Stewardship Report

Texas

Firing Sites

Risk Reduction Standard 3 Portion

- Active Site Locations

- - Risk Reduction Standard 3 Sites

~ Soil Contamination

0 1,500 3,000

Feet

36

Pantex Plant

For release sites at Pantex recommended for closure under Risk Reduction Standard 3, the level of confidence for attaining regulatory approval is medium. A Baseline Risk Assessment is required for Risk Reduction Standard 3 sites. Pantex has submitted a draft Baseline Risk Assessment to the TNRCC. The majority of issues concerning contaminants of concern selection and exposure modeling have been resolved. The objective of the Baseline Risk Assessment is to analyze Pantex Plant site conditions in the absence of remedial action and to provide human health and environmental baseline data to be used in evaluating remedial action alternatives. Human health impacts are quantified through a process that estimates average daily doses (i.e., intake) for likely exposure scenarios that could place humans in contact with contaminated environmental media. Exposure to contaminated media can occur through a number of exposure routes such as ingestion, dermal contact, and inhalation. Health impacts are expressed differently depending on the type of health impact caused by the contaminant. The health impact end-point for carcinogenic chemical contaminants is expressed as the lifetime risk of cancer incidence (i.e., the probability of contracting cancer from exposure to the contaminant over a lifetime). Health impacts for exposure to non-carcinogenic chemicals are expressed as a hazard quotient, which is the ratio of the estimated average daily dose to the reference dose for the chemical.

General target cleanup levels for media closed under Risk Reduction Standard 3 are concentrations that: 1) represent upper-bound lifetime cancer risk of individual carcinogenic contaminants ofO.OOOOO 1 and a cumulative excess cancer risk from all carcinogens combined not to exceed 0.0001, each in consideration of all applicable exposure pathways and standard exposure scenarios; 2) comply with National Ambient Air Quality Standards; and 3) for systemic toxicants, do not exceed a hazard index or hazard quotient of one.

For groundwater that is a current or potential source of drinking water and is closed under Risk Reduction Standard 3, specific cleanup levels must not exceed maximum contaminant levels promulgated under the Safe Drinking Water Act. If maximum contaminant levels do not exist, calculated medium-specific concentrations apply, using standard exposure factors consistent with current, historical, and/or probable future land use. If future land use other than residential is appropriate for the site/release area, and demonstration can be made that institutional or legal controls will effectively prevent use of contaminated groundwater, the extent of plume remediation may be revised to allow cleanup to alternate concentration levels.

Specific media cleanup levels for soil/sediment closed under Risk Reduction Standard 3 include medium-specific contaminant concentrations that are protective of air, surface water, and groundwater based on sound scientific principles, including fate and transport modeling. Contaminant concentrations determined protective of other media must be maintained over time, taking into account any implemented engineering controls.

Institutional and Engineered Controls

Deed recordation, which limits the use of media closed under Risk Reduction Standard 3, is required. In addition to deed recordation, post-closure care is required, which may be in the form of engineered controls and/or access/activity restrictions that limit exposure to contaminants to durations that result in excess risk levels below Risk Reduction Standard 3 cleanup levels. Exposure limitations can include construction of engineered controls, procedural restrictions that limit access to specified duration and frequency, and/or procedural implementation of protective equipment protocols that decrease or eliminate exposure to contaminant concentrations. Implementing mechanisms to ensure that deed restrictions are adhered to include management controls provided in Plant Standards, Directives, and Operating Procedures for activities conducted on land owned by the DOE. Deed restrictions and other institutional controls placed on property not owned by the DOE will require negotiation and agreement with the applicable landowners.

It is anticipated that, in some cases, fencing to provide access restriction will accompany deed restriction of Risk Reduction Standard 3 sites to ensure land use is consistent with covenant restrictions. Other engineered controls currently planned are containment technologies, including soil/sediment liners (for certain ditches) and

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National Defense Authorization Act (NDAA) Long-Term Stewardship Repm·t

caps/covers (for certain landfills and other soil contamination areas). It is anticipated that pump and treat and a combination of barriers (bio and/or hydraulic) and in-situ bioremediation/chemical treatment will be the primary activities conducted after completion of perched groundwater corrective action construction.

3.2.1 Soil

Of the 249 identified release sites at Pantex that correspond to solid waste management units and areas of concern, approximately 50 of the sites, including soils sites, sediments sites, and onsite perched groundwater, have been or will be recommended for closure under Risk Reduction Standard 3. Of the 50 sites recommended for closure under Risk Reduction Standard 3, approximately 37 of the sites deal specifically with residually contaminated soil. It is estimated that approximately 110 surface acres of soil will be closed under Risk Reduction Standard 3.

Releases affecting soil at Pantex have resulted from past production operations associated with fabrication of chemical explosive components for nuclear weapons, nuclear weapon assembly/disassembly, weapon modification and repair, surveillance testing and thermal treatment/disposal of chemical explosives and nonradioactive components. Media contamination from these operations occurred by discharging wastewater to unlined ditches, onsite treatment/disposal of high explosives contaminated solvents, spills and leaks of raw and produced materials, onsite landfilling of solid wastes, and onsite discharge of wastewater to playa lakes. The primary contaminants at Risk Reduction Standard 3 sites include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds, including trichloroethylene, chrysene, acetone, benzo(a)pyrene and benzo(a)anthracene.

Risk Reduction Standard 3 soil sites include soils less than 0.6 meter (two feet) below surface elevation (surface soils) and greater than 0.6 meter (two feet) below surface elevation (subsurface soils). The significance of delineating the soil sites regarding the upper 0.6 meter (two feet) vs. below 0.6 meter (two feet) in surface grade is the exposure pathway analysis required by environmental regulations. The primary exposure pathway for surface soils is the air ingestion pathway. The primary exposure pathways for subsurface soils is the soil-togroundwater and subsequent groundwater exposure pathway and soil-to-air ingestion pathway for construction/excavation workers. Risk Reduction Standard 3 sites require post-closure care once the remedy is implemented to maintain protectiveness of human health and the environment.

For soil media release sites at Pantex that have been or will be recommended for closure under Risk Reduction Standard 3, the level of confidence for attaining regulatory approval is medium. Because of the fact that not all investigation and cleanup reports have been reviewed and approved by TNRCC, and due to the fact that corrective measures studies/designs approval are dependent on final approval of the investigations, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Based on regulatory and public input received on proposed corrective actions, the final preferred corrective action alternative may differ than that currently anticipated. Additional investigations have the potential to identify conditions requiring revision of previous recommendations.


Long-term stewardship goals for soil sites closed under Risk Reduction Standard 3 are to ensure land use is consistent with restrictions imposed by deed recordations and to ensure controls are maintained that comply with closure requirements. In general, Risk Reduction Standard 3 closures of sites will be conducted to meet nonresidential cleanup requirements. Activities conducted to meet these goals may include implementation of procedural limitations for site use, construction and maintenance of signs, fencing, etc., and administrative limitations of site operations.

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Pantex Plant

3.2.2 Groundwater

The estimated volume of onsite perched groundwater that requires treatment to meet Risk Reduction Standard 3 cleanup levels is approximately 3.8 billion liters (one billion gallons). Releases affecting perched groundwater at Pantex have resulted from past production operations associated with fabrication of chemical explosive components for nuclear weapons, nuclear weapon assembly/disassembly, weapon modification and repair, and surveillance testing and disposal of chemical explosives and non-radioactive components. Perched groundwater contamination from these operations is believed to have occurred primarily by discharging wastewater to unlined ditches, onsite treatment/disposal of high explosives contaminated solvents, and spills and leaks of raw and produced materials. The primary contaminants in onsite perched groundwater are the high explosives RDX, TNT, and HMX; the heavy metal chromium; and the volatile organic compound trichloroethylene.

Groundwater closed under Risk Reduction Standard 3 requires post-closure care after remedy implementation to maintain protectiveness of human health and the environment. Groundwater use must be consistent with deed restrictions (such as restrictions for industrial use only or no allowed use). The groundwater contamination at Pantex is primarily restricted to a perched aquifer located at a depth of approximately 82 meters (270 feet) below surface level. Detection of contaminants above drinking water standards have recently been discovered in the Ogallala aquifer in a monitoring well near the northwest boundary of the Pantex Plant and in an Ogallala well located southeast of the Plant. The Ogallala aquifer is the primary irrigation and drinking water source for the Texas Panhandle. Investigation is currently ongoing to determine the nature and extent of the newly identified contaminants.

For impacted groundwater at Pantex that will be recommended for closure under Risk Reduction Standard 3, the level of confidence for attaining regulatory approval is medium. Because of the fact that not all investigation and cleanup reports have been reviewed and approved by the TNRCC, and due to the fact that corrective measures studies/designs approval are dependent on final approval of the investigations, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Based on regulatory and public input received on proposed corrective actions, the final preferred corrective action alternative may differ than that currently anticipated. Additional investigations have the potential to identify conditions requiring revision of previous recommendations.


The remediation and long-term stewardship goals for onsite perched groundwater are the protection of the Ogallala aquifer, reduction of contaminant concentrations to levels that are protective of residential use at the Pantex Plant property boundary and offsite, and to identify and implement beneficial uses for treated groundwater.

3.2.3 Surface Water/Sediment Area

It is estimated that approximately 20 surface hectares (50 acres) of sediment media will be closed under Risk Reduction Standard 3. The primary contaminants at Risk Reduction Standard 3 sediment sites include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds, including trichloroethylene, chrysene, acetone, benzo( a)pyrene and benzo( a)anthracene. The primary reason for residual contamination of surface water/sediments is the historical practice of discharging untreated wastewater. Untreated wastewater is no longer discharged to ditches or surface water bodies.

There are currently no surface water sites at Pantex identified for closure under Risk Reduction Standard 3. Surface sediments are less than 0.6 meter (two feet) below surface elevation. Sediments greater than 0.6 meter (two feet) below surface elevation are categorized as subsurface soils. Sediments at Pantex are associated

Texas 39


primarily with a network of constructed ditches, including some that direct surface water flow away from buildings within interior zones of the Pantex Plant.

For release sites associated with sediments at Pantex that have been or will be recommended for closure under Risk Reduction Standard 3, the level of confidence for attaining regulatory approval is medium. Because of the fact that not all investigation and cleanup reports have been reviewed and approved by the TNRCC, and due to the fact that corrective measures studies/designs approval are dependent on final approval of the investigations, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Based on regulatory and public input received on proposed corrective actions, the final preferred corrective action alternative may differ than that currently anticipated. Additional investigations have the potential to identify conditions requiring revision of previous recommendations.


Long-term stewardship goals for sediment sites closed under Risk Reduction Standard 3 are to ensure land use is consistent with restrictions imposed by deed recordations and to ensure controls are maintained that comply with closure requirements. In general, Risk Reduction Standard 3 closures of sites will be conducted to meet nonresidential cleanup requirements. Activities conducted to meet these goals may include implementation of procedural limitations for site use, construction and maintenance of signs, fencing, etc., and administrative limitations of site operations.

3.2.4 Engineered Units

It is estimated that up to five solid waste management units, comprising approximately 16 surface hectares (40 acres or 1, 7 42,400 square feet) of soil/sediment, will be closed under Risk Reduction Standard 3 using engineered controls. Releases affecting soil at Pantex have resulted from past production operations associated with fabrication of chemical explosive components for nuclear weapons, nuclear weapon assembly/disassembly, weapon modification and repair, surveillance testing and disposal of chemical explosives and non-radioactive components. Media contamination from these operations occurred by discharging wastewater to unlined ditches, onsite treatment/disposal of high explosives contaminated solvents, spills and leaks of raw and produced materials, on-site landfilling of solid wastes, and on-site discharge of wastewater to playa lakes. The primary contaminants at sites for which engineered units will be constructed to contain and limit exposure include the metals chromium, lead, and barium; the high explosives RDX, HMX, and TNT; and volatile and semi-volatile organic compounds including trichloroethylene, chrysene, acetone, benzo(a)pyrene and benzo(a)anthracene.

Containment in the form of engineered caps/covers/ have been planned for up to three sites at Pantex to eliminate exposure pathways and receive Risk Reduction Standard 3 closure approval. Ditch liners are also being considered for Risk Reduction 3 closure of ditch sediments at two solid waste management units that can not be economically remediated by interim corrective measures such as hot-spot removal. Design/structural features of currently considered engineered containment units include asphaltic concrete caps with compacted soil and limestone bases; traditional multi-layer RCRA caps; innovative water harvesting covers; and compacted soil coverings. Fencing, high-density liners, and asphaltic concrete liners are also being considered for ditch/sediment sites.

For release sites at Pantex that have been or will be recommended for closure under Risk Reduction Standard 3, the level of confidence for attaining regulatory approval is medium. Because of the fact that not all investigation and cleanup reports have been reviewed and approved by the Texas Natural Resource Conservation Commission, and due to the fact that corrective measures studies/designs approval are dependent on final approval of the investigations, the possibility exists that additional investigations may be necessary to resolve regulatory comments on documents previously provided. Based on regulatory and public input received on

Texas 40

Pantex Plant

proposed corrective actions, the final preferred corrective action alternative may differ than that currently anticipated. Additional investigations have the potential to identify conditions requiring revision of previous recommendations.


The long-term stewardship goals for sites that require engineered units to meet closure requirements of Risk Reduction Standard 3 include protection of human health and the environment in the most effective, costefficient, and most unobtrusive manner possible; and to continuously evaluate performance of the units to determine if new or different technologies can be implemented that will result in less expensive or more effective remediation of residual contamination. Activities necessary to achieve these goals include routine maintenance and monitoring, replacement, as necessary, and continued research of innovative remediation methodologies and alternatives.

3.2.5 Estimated Long-Term Stewardship Costs for Risk Reduction Standard 3 Sites

The table below identifies the estimated costs for performing long-term stewardship activities at the Risk Reduction Standard 3 Sites portion (by ten-year intervals). Risk Reduction Standard 3 closures represent about 95% of long-term stewardship costs at Pantex. Costs include corrective action system operation, monitoring, maintenance, and remedial system upgrade. The primary costs entail groundwater treatment associated with an estimated 60 extraction, 15 injection, and 100 corrective action monitoring wells; associated operation and upkeep; monitoring and analytical costs; and treatment system management. The primary costs associated with engineered controls for Risk Reduction Standard 3 soil/sediment site closures include monitoring, maintenance, and, as necessary, replacement.

Long-Term Stewardship Costs (Constant Year 2000 Dollars)

FY 2000- FY 2011- FY 2021- FY 2031- FY 2041- FY 2051- FY 2061- Estimated FY 2010 FY 2020 FY 2030 FY 2040 FY 2050 FY 2060 FY 2070 Total

$10,916,000 $16,711,000 $20,710,000 $18,163,000 $13,785,000 $12,105,000 $9,408,000 $101,798,000

4.0 FUTURE USES

Release sites closed under Risk Reduction Standard 2, corresponding to approximately 280 surface hectares (700 acres), will be cleaned up to approved residual contaminant levels allowed for industrial use and will be deedrestricted for industrial activities. Release sites closed under Risk Reduction Standard 3, corresponding to approximately 81 surface hectares (200 acres), will be cleaned up to approved residual contaminant levels allowed for site specific and/or industrial use and will be deed restricted for use, depending on cleanup levels achieved and applicable post-closure care requirements. It is not anticipated that controls placed on residually contaminated sites and perched groundwater at Pantex will affect the ongoing site mission. If technical limitations result in not achieving remediation goals for perched groundwater, use of that resource may be restricted or eliminated.

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National Defense Authorization Act (NOAA) Long-Term Ste\\ardship Report

For more information about the Pantex site, please contact:

Hugh Hanson, Environmental Restoration Engineer U.S. Department of Energy , Amarillo Area Office P.O. Box 30030 Amarillo, TX 79120 Phone: 806-477-3164 or visit the Internet website at http://www.em.doe.gov

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Technology

Texas