ML20211A171
| ML20211A171 | |
| Person / Time | |
|---|---|
| Issue date: | 09/30/1997 |
| From: | NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | |
| Shared Package | |
| ML20211A169 | List: |
| References | |
| REF-WM-63 NUDOCS 9709240142 | |
| Download: ML20211A171 (21) | |
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ENCLOSURE 1
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Y COMPLETION REVIEW REPORT FORTHE REMEDIAL ACTION AT THE MEXICAN HAT / MONUMENT VALLEY -
URANIUM MILL TAILINGS REMEDIAL ACTION PROJECT SITE Septembe r 1997
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~4i TABLE OF CONTENTS s
-SmuGD Page I N TRO D U C TI O N................................................... -.......
1 1.0 BAC KG R OU N D,.....................................................
1 1.1 U M TR C A............................................................
1 1.2 CONCURRENCE PROCESS FOR THE SELECTION OF DOE'S REMEDIAL AC TI O N S,.......................,,.............................,..
1 1.3 CONCURRENCE PROCESS FOR THE PERFORMANCE OF DOE'S REMEDIAL AC TI O N S........................................................
2 1.4 MEXICAN HAT / MONUMENT VALLEY SITES...
-2 1.5 COMPLETION REVIEW REPORT ORGANIZATION..............,........
6 :
2.0 ANALYSIS OF DOE REMEDIAL ACTION PERFORMANCE '.,..................
6 2.1 PR EVIOUS ACTION S................................................
6 2.2 REVIEW OF REMEDIAL ACTION PERFORMANCE,.....
6 1
2.2.1 Geotechnical Engineering................
7 2.2.2 Surface Water Hydrology and Erosion Protection...........,....,....
8 2.2.3 : Radiation Cleanup and Control.....................
9 2.2.4 Water Resourves Protection.....
10
- 3. 0 S U M MARY....................................
................... 11 4.0 R E F E R E N C E S.................................................... 11 APPENDIX A - NRC SITE VISITS TO THE MEXICAN HAT / MONUMENT VALLEY
-- U M TRA PR OJ E CT S ITE................................................. A-1
- APPENDIX B - UMTRCA, THE EPA STANDARDS, AND THE PHASED UMTRA P R OJ E CT........................................................... B-1 i
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?-1,1 ~. Location of the Monument Valley and Mexican Hat Sites................,..-.,..
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MEXICAN HAT / MONUMENT VALLEY UMTRA PPOJECT SITE COMPLETION REVIEW REPORT INTRODUCTION The sites near Mexican Hat, Utah, and Monument Valley, Arizona, were designated as two of the 24 abandoned uranium mill tailings sites to be remediated by the U.S. Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA).
UMTRCA requires, pursuant to Section 104(f)(1), that the U.S. Nuclear Regulatory Commission concur with the DOE's determination that the remedial action has been properly completed.
This Completion Review Report (CRR) documents the NRC staffs basis for its concurrence decision with respect to DOE's Certification Summary for the completion of surface remediation at the Mexican Hat and Monument Valley sites.
1.0 BACKGROUND
1.1 LLMTRCA Title I of UMTRCA provides for remedial action at abandoned uranium mill tailings sites and associated vicinity properties. The purpose of this legislation is to protect the public health and safety and the environment from radiological and non-radiological hazards associated with the process related materials at these sites.
UMTRCA directs DOE to select and perform remedial actions at 24 abandoned uranium mill tailings sites to ensure compliance with the general environmental standards promulgated by the U.S. Environmental Protection Agency (EPA) under Section 275(a) of the Atomic Energy Act of 1954, as amended by UMTRCA. UMTRCA also requires DOE to obtain NRC's concurrence with DOE's selection and performance of the remedial actions. Following completion of the remedial actions, UMTRCA authorizes NRC to license the long term custody, maintenance, and monitoring of the disposal sites to ensure continued protection of the public health and safety and the environment. Appendix B includes a more detailed discussion of this legislation.
1.2 CONCURRENCE PROCESS FOR THE SEL'ECTION OF DOE'S REMEDIAL ACTIONS To document its selection of the remedial action to be implemented at a particular site, DOE develops and issues a Remedial Action Plan (RAP) under its Uranium Mill Tailings Remedial Action (UMTRA) Project. The RAP describes the series of betivities and presents the design proposed by DOE to provide for the long-term protection of the public and the environment.
Usually this involves cleanup of the processing site, adjacent windblown areas, and vicinity properties in addition to stabilization of the residual radioactive materials. In addition, DOE issues a Remedial Action inspection Plan (RAIP), which establishes the quality control program of testing and inspection that will be employed for the remedial action. In accordance with UMTRCA Section 108(a)(1), the NRC staff reviews and concurs with the RAP and the RAIP, and any subsequent modifications. By its concurrence in the remedial action selection, the 1
NRC staff concludes that the planned remedial actions will comply with EPA's applicable standards in 40 CFR 194, Subparts A, B, and C. The basis for the concurrence in DOE's selection of remedial action is documented in a Technical Evaluation Report (TER),
1.3 CONCURRENCE PROCESS FOR THE PERFORMANCE OF DOE'S REMEDIAL 6_CTION_S The remedial action work is performed by DOE contractors under Federal procurement regu!alions. During construction, DOE inspects and documents activities in accordance with the UMTRA Project Quality Assurance Plan, the RAIP, and the RAP, in addition, the NRC staff conducts independent inspections during construction, as determined necessary.
Upon completion of the remedial action, DOE compiles construction records and prepares a completion report to document that remedial actions were performed in accordance with the RAP or RAP modifications, and the RAIP, Based on this information, DOE certifies that all provisions of the RAP have been satisfied and, therefore, that the remedial actions comply with the applicable EPA standards in 40 CFR 192.
Based on its eview of DOE's documentation, and on its site visits and observations, NRC makes a concurrence decision with regard to DOE's reraedial action completion determination for each site, and then documents the basis for this concurrence decision in the Completion Review Report (CRR). By its concurrence in the remedial action performance, the NRC staff concludes that the remedial action has been completed in accordance with the NRC approved design. NRC's concurrence with DOE's completion determination fulfills the Commission's responsibility under UMTRCA Section 104(f)(1).
1.4 MEXICAN HAT / MONUMENT VALLEY SITES The principal feature of the remedial action is co-disposal and stabilization of the Mexican Hat and Monument Valley contaminated materials at the Mexican Hat disposal site.
Monument Valley Site The Monument Valley site is a 100-acre property located on the Navajo Reservation in Arizona, 17 road miles south of the Mexican Hat disposal site (Figure 1.1). The tailings are on the west side of Cane Valley. The mill at tha Monument Valley site was operated from 1955 to 1968 by Vanadium Corporation of America and its successor, Foote Mineral Company. According to the Completiors Report (CR), the pre-remediated site consisted of two tailings piles covering approximately 28 acres and containing approximately 928,000 cubic yards of tailings; concrete building foundations; and debris.
During 1993 through early 1994, the Monument Valley contaminated materials were excavated and hauled to the Mexican Hat site for placement on the disposal cell, and the Monument Valley site wr.s backfilloa, graded to drain, and vegetated.
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FIGURE 1,1 LOCATION OF THE MONUMENT VALLEY AND MEXICAN HAT SITES TOOLVFF
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e Mexican Hat Disposal Site The Mexican Hat disposal site is a 235 acre property located approximately eight miles north of the Utah-Arizona border and two miles southwest of Mexican Hat. It lies within the Navajo Reservation (Figuro 1.1). To the north is the San Juan River and to the west is the Alhambra Rockf The mill was constructed and operated from 1957 to 1963 by Texas-Zine Minerals Corporation. The plant was then sold to Atlas Corporation and operated until 1965. According to the CR, the pre-remediated site consisted of two tailings piles covering approximately 69 acres and containing approximately 3,386,000 cubic yards of tailings; several original mill buildings; and structures and concrete pads for the former mill building and trade school.
Beginning in 1989 and continuing through January 1990, the upper tailing pile and the windblown and waterbome contaminated materials from the Mexican Hat site were relocated to the lower pile. During 1993 through early 1995, the contaminated materials from the Monument Valley site were hauled and placed on the Mexican Hat disposal cell pile, covered with a radon / infiltration barrier, and graded for erosion protection. The former mill office building was left intact.
The remedial action performed by DOE consis'ed of the following major activities:
1.
The lower tailings pile at Mexican Hat was recontoured, and approximately 1,210,000 cubic yards of Mexican Hat tailings from the upper pile and off-pile contaminated materials were placed on top of the lower pile.
2.
Approximately 1,093,000 cubic yards of Monument Valley contaminated materials were transported to and placed in the upper ten feet of the Mexican Hat tailings pile.
3.
The final disposal cell (Figure 1.2) covers approximately 68 acres and contains approximately 3,800,000 cubic yards of centaminated materials, including tailings, contaminated soils, and mill site debris. It abuts a steep ridge to the south and rises approximately 50 feet above the surrounding terrain to the north, east, and west. The top of the disposal cell was built with a 2 percent slope to the northwest and with side slopes of 20 percent.
4.
The final cover over the tailings consists of a 2-foot-thick radon / infiltration barrier of compacted uncontaminated soil amended with bentonite, covered by a 6 inch-thick bedding and filter layer, and finally a 1 foot-thick rock layer.
The NRC was not involved with the actual remedial action activities which were performed by the DOE contractors. However, DOE obtained NRC concurrence with the sitt, construction design and five significant modifications known as Project Interface Documents (PIDs). NRC also performed on-site construction reviews to monitor the progress of the construction activity (see Appendix A).
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FIGURE 1.2 FINAL EMBANKMENT-MEXICAN HAT SITE d
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1.5 COMPLETION REVIEW REPORT ORGANIZATION The purpose of this CRR is to document the NRC staff review of DOE's Mexican l
Hat / Monument Vallev Completion Report (CR) (DOE,1997). Section 2 of this report presents the analysis of remew; action construction. This section is organized by technical discipline and addresses engineering and radiation protection aspects of the remedial action. Appendix A provides a listing of NRC staff visits to the Mexican Hat and Monument Valley sites.
Appendix B provides a detailed description of the requirements of UMTRCA and the resulting phased process of the UMTRA project.
2.0 ANALYSIS OF DOE REMEDIAL ACTION PERFORMANCE 2.1 PREVIOUS ACTIONS NRC staff, based on its review oi the RAP (DOE,1993a-f), and the RAIP (MK-F,1994) concurred that the remedial action, as designed, would meet the applicable EPA standards.
This ccncurrence was based on technical findings that there is reasonable assurance that the selection of the remedial action would meet the standards for long-term stability, radon attenuation, water resources protection, and cleanup of contaminated land and buildings.
Staff reviews included assessments in the areas of geology, geotechnical engineering, surface water hydrology, and health physics. The NRC concurred on the final RAP and the RAIP on February 27,1996. The basis for the NRC staffs concurrence in DOE's selection of remedial action at the Mexican Hat and Monument Valley sites is documented in a Technical Evaluation Report (TER) issued in February 1996 (NRC,1996).
2.2 REVIEW OF REMEDIAL ACTION PERFORMANCE NRC staffs primary objective in reviewing DOE's certification of remedial action completion is to determine whether the remedial actions have been performed in a manner consistent with specifications provided in the RAP, RAP modifications or PIDs, and the RAIP, and if not, that deviations to these specifications still result in compliance with the EPA standards. In support of this action, the NRC staff participated in site reviews (See Appendix A), field observations, assessments of on site data and records, and review of DOE Site Audit Reports. During remsdial action construction activities, there were conditions encountered which required modifications of the original remedial action plan. These conditions and the associated *sig-changes were submitted by DOE as five Class i PIDs, i.e., those related to meeting the EPA standards, and were concurred in by the NRC staff. These PID's are listed in the Executive Summary of Volume 1 of the CR and are reflected in the as-built conditions presented in the CR.
The following sections present the results of the review of remedial action performance by individual technical discipline. Note that for the Mexican Hat / Monument Valley remedial action completion review, the pertinent technical disciplines are: 1) geotechnical engineering,2) surface water hydrology and erosion protection,3) radiation protection, and 4) water resources protection.
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2.2.1 Geotechnical Engineering The NRC staff reviewed the Mexican Hat / Monument Valley Final Completion Report (DOE, 1997) to determine whether the geotechnical engineering aspects of the remedial action had been completed in accordance with (1) the applicable technical specifications in the RAP (DOE,1993), (2) the RAIP, Revision 1, Review D (MK-Ferguson,1994), and (3) applicable Class i PIDs. NRC did not review all of the testing and inspection records due to the voluminous amount of documentation. However, the staff did review representative records during on-site visits during construction. In addition, the staff's review was based on statements made by DOE in the completion report that all requirements had been complied with, descriptions of construction operations, as-built drawings, summaries of laboratory and field testing data, and DOE Quality Assurance Audits.
Based on its review of the geotechnical engineering aspects of the remedial action completion documentation, the NRC staff noted the following:
1.
DOE concluded that appropriate tests (gradation and classification) and inspections were performed to assure that the proper type of material was placed for each feature of construction. The loose thickness of the lifts was continuously monitored to ensure compliance with the specifications for that material. Placement and compaction operations were routinely inspected and tested to assure that the moisture and density requirements were met and that the soil moisture was uniform inroughout the compacted lifts.
2.
DOE concluded that laboratory and field testing was adequately documented indicating that they were conducted in accordance with acceptable test procedures by trained and qualified personnel The Completion Report sho' s that frequencies cf materials testing and inspection comply 3.
w with the frequencies specified in the RAIP, 4.
Continuous inspect;ons by DOE or its agents confirmed that the volume of organics included in the construction materials was limited to the range specified in the RAP.
5.
The radon barrier layer was continually inspected by DOE or its agents to ensure that the specified lift thicknesses and compaction levels were achieved.
6.
The material type, placement, and compaction methods specified for the radon barrier layer resulted in the desired permeability and density of the barrier.
7.
As-built drawings adequately document that the completed remedial action was consistent with the design concurred in by the NRC.
8.
DOE concluded that final slope, elevation, and placement of the disposal cell cover were adequately inspected to ensure that the final conditions were consistent with those stated in the RAP and finai design.
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Based on the above conclusions, and on the results of on-site inspections performed by the NRC staff during construction, the NRC staff concludes that the geotechnical engineering aspects of the construction were performed in accordance with the design and specifications identified in the RAP and the RAIP.
2.2.2 Surface Water Hydrology and Erosion Protection NRC staff reviewed the surface water hydrology and erosion prctection aspects of remedial actions at Mexican Hat to ensure that they were constructed in accordance with the applicable construction specifications as stipulated in the RAP, RAP modifications, RAIP, and the final design. Areas of review included construction operations, laboratory and field testing, and quality assurance audits, in addition, the review was also based on NRC observations of the remedial actions ar.d review of records and testing during an NRC onsite inspection.
The remedial action design included erosion protection in several specific areas, including: (1) riprapped top and side slopes; (2) riprapped drainage channels; and (3) a buried riprap toe adjacent to tha side slope. The top and side slopes of the cell and the channels were designed to prevent long term erosion and gullying of the disposal cell. The buried riprap toe was placed to prevent eros;on and migration of gullies toward the cell.
The NRC sta'f reviewed each of these features and determined that testing, placement, av configuration complied with specifications in the RAP, RAP modifications, and the RAF. The review was partially based on NRC staff observations and review of onsite recorde 4.sg the remedial actions, as well as assessment of the verification results presented in the DOE Completion Report, in addition, the NRC staff reviewed records of the placement of riprap on the top and side slopes of the cell and in the drainage channels.
During the review, the NRC staff noted the following:
1.
Tests (gradation and durability) and inspections were performed by DOE or its agents to ensure that erosion protection materials were properly selected. The review of the documentation indicated that placement of materials was routinely inspected by DOE or its agents to ensure that the rock size and gradation specifications were met. Likewise, the thickness of the rock layers were verified periodically by DOE or its agents to ensure compliance with the specifications for the particular type of material.
2.
Laboratory and field testing was conducted by DOE or its agents in accordance with specified test procedures.
3.
Testing and inspection frequencies for materials used at the site for erosion protection were documented by DOE as complying with the frequencies specified in the RAIP, Based on NRC staff observations and review of onsite records during rerredial actions, as well as assessment of the venfication results presented in the Completion Raport, the NRC staff concludes that the required durability and gradation tests were performed during the remedial action. The riprap is of adequate quality and has been acceptably placed. The NRC staff concurs the remedial action has been adequately completed at Mexican Hat, with respect to erosion protection.
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2.2.3 Radiation Cleanup and Control The NRC staff reviewed radiation cleanup aspects of remedial actions at the Mexican Hat, Utah and Monument Valley, Arizona sites to ensure that residual radioactive materials were cleaned up in accordance with specifications in the RAP and the final design. The remedial action involved the consolidation of contaminated materials from the Mexican Hat site into a single pile on site with contaminated materials from the Monument Valley site relocated and placed on top of the Mexican Hat materials. Areas of review included contaminated material excavation, cleanup verification procedures and data, and application of supplemental standards. In addition, the construction data for the disposal cell cover were reviewed to ensure compliance with the RAP design for limiting radon releases (see Section 2.2.1), and the final radon attenuation calculation was reviewed to ensure compliance with the long-term radon flux standard in 40 CFR 192.02. The review was based primorily on the staff's assessment of information presented in the DOE Mexican Hat / Monument Valley Completion Report (CR).
The criteria for site cleanup and radon attenuation design were established in the RAP and concurred in by NRC staff as providing assurance that the processing site and disposal cell would meet the EPA requirements of 40 CFR Part 192. The criterion for soil radium (Ra-226) requires cleanup at the processing site and on adja cent lands (EPA standards,40 CFR 192.12) such that the average Ra 226 and Ra-228 levels Lbove background in each 100-m' area do not exceed either 5 pCi/g in the top 15 cm of soil, or 15 pCi/g in any underlying 15-cm layer. The RAP also established a supplemental cleanup standard which requires that thorium (Th-230) be excavated such that the bulk (corrected for percent cobbles) 1000-year Ra-226 concentrations from present levels of Ra-226 and Th-230 meet the Ra-226 cleanup limits.
Two buildings remained on the Mexican Hat processing site. DOE indicated that the buildings did not require cleanup so cleanup criteria were not specified in the RAP.
The RAP final radon attenuation (barrier) design was based on construction of a compacted clayey (10 percent bentonite by weight) soil radon barrier 2 feet thick. The NRC staff in its TER evaluation of the RAP stated that measurements made during construction of the cell should be incorporated into the final flux analysis in the CR. A radon flux calculation was provided in the CR incorporating some final test data, as discussed below.
During the review, with respect to the above criteria and commitments, NRC staff noted the following:
1.
Soil Cleanup: Appendix J of the CR indicates that all tailings contaminated areas on the Mexican Hat and Monument Valley sites were cleaned according to DOE UMTRA Project procedures.
2.
Cleanup Verification: The CR indicates that standard DOE UMTRA Project procedures for soit verification were appropriately applied at the two sites, and the quality control program complied with plan criteria. The data indicate that all soil samples and areas scanned by the RTRAK or hand-held gamma detectors met the EPA soil Ra 226 standards.
Measurements for Th-230 were conducted and the estimated 1000-year Ra-226 concentrations from present levels of Ra-226 and Th-230 were less than or equal to the radon standard. The CR indicates that by cleaning up Th-232 at the Mexican 9
4 Hat site to the appropriate enteria, Ra 228 would also be remediated. The data indicate that measurements for Th 232, as a surrogate for Ra 228, were done at the Mexican Hat site and met the 5 pCUq criterion at any depth. No Th 232 measurements were done at the Monument Valley site becat.se site characterization data indicated that there were no elevated levels of Th 232 at the site.
Appendix J of the CR states that the shop buiHing t" d some elevated surface activity, tw the activity met tM NRC one square meter average limit. The data provided indicates that the building does meet a!l release criteria. Also, the CR indicates that the other building (former clinic) was assessed as part of a vicinity property inclusion survey and did not require remediation.
3.
Radon Flux: Long term radon flux estimates for the Mexican Hat disposal cell cover were provided in CR calculation 9-42105-01. The radon flux model utilized average measured Ra 226 and emanation fraction values for as placed contam;nated materials, sampled at 20 locations on the '.ill.
Th-230 was also measured, but the resulting 1000-year Ra 226 values were not used in the calculation because the influence would not be significant. Although, measured values for some of the radon barrier parameters weta not obtained to replace earlier estimates and the rnodeled thickness of some of the contaminated material may not be conservative, the NRC staff considers the over all DOE radon model conservative. The DOE calculation resulted in an average long term radon flux of 12.8 pCi/m's from the top of the radon barrier.
Radon flux measurements were performed on the radon barrier and averaged 0.05 pCl/m's. Based on this information and the findings discussed under Sections 2.2.1 and 2.2.2 of this CRR the integrity of the radon barrier will not be significantly degraded for the design life of t.
ill, NRC staff concludes that there is adequate assurance that the long-term radon flu.
andard of 20 pCi/m's will be met.
Based on the above evaluations, the NRC staff concludes that commitments and requirements stated in the RAP were fulfilled and that data in the CR provides assurance that the soil cleanup and disposal cell cover radon control standards have been met at tho Mexican Hat and Monument Valley sites.
2.2.4 Water Resources Protection Review Results The NRC staff reviewed the construction activities conducted during the performance of remedial actions that relate to ground-water resource protection. During its review, the NRC sta'f noted the following:
1.
No as built drawings for well abandonment were included in the Completion Report for the Mexican Hat or Monument Valley sites, isowever two photographs showed well abandonment activities proceeding at the Mexican Hat site in 1988. No schedules or specifications for well abandonment for either site were included in the RAP (DOE,1993).
Discussion with the DOE project manager indicated that well abandonment was performed in 1988, as part of a previous DOE remedial action and was not specified as a part of this RAP Some wells remain at both the Mexican Hat an't Monument Valley sites and will be used or abandoned as part of the groundwater reshmtion program.
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Based on the above discussion with the DOE project manager and results of NRC onsite inspections, the NRC staff concludes that the ground-water protection aspects of the remedial
. action were completed in accordance with the design and procebres identified in the RAP, and the RAIP.
3.0
SUMMARY
l NRC staff reviewed geotechnical engineering, surface water hydrology and erosion protection, radiation protection, and water resources protection aspects of the remedia; action performed at the Mexican Hat and Monument Valley uranium mill tailings sites. The purpose of this review was to determine whether DOE had performed remedial actions at the site b accordance with specifications in the RAP, RAP modifications, and other supporting project documents, and thus with the EPA standards in 40 CFR Part 192, Subparts A C. Based on its i
review of the Final CR and on observations made during periodic on-site construction. sits, the -
NRC staff conc!udes that DOE performed remedial action at the W.nican Hat arid Mariument Valley sites in accordance with the EPA standards. Therefore, NRC concurt, with DOE's certification of completion of the Mexican Hat / Monument Valley remedial action.
4.0 REFERENCES
U.S. Department of Energy (DOE), Washington, D,C.
--, " Final Remedial Action Plan for Co-Disposai and Stabilization of Monument Valley and Mexican Hat Uranium Mill Tailings at Mexican Hat, Utah" and Appendices A F, February 1993.
-, " Draft Completion Report, Mexican Hat / Monument Valley," Volumes 16A, November 1995.
--, " Final Audit Report of Remedial Action Construction at the UMTRA Project Mexican Hat, UT/ Monument Valley, A7. Sites," November 1995.
Vinal Completion Report, Mexican Hat / Monument Valley," Volumes 16A, April 1997, and page changes (June 4,1997, June 16,1997, and July 29,1997).
MK Ferguson,
- Remedial Action Inspection Plan, Mexican Hat / Monument Valleu IJranium Mill Tailings Sites," September 1994.
U.S. Nuclear Regulatory Commission, Washington, D.C., " Final Technical Evaluation Report for the Proposed Remedial Action Plan for the Co-Disposal of the Monument Valloy and Mexican Hat Contaminated Materials at the Mexican Hat Tailings Site, Utah,"
February 1996.
, Division of Low Level Waste Management and Decommissioning, *NRC Staff Technical Position on Testing and Inspection Plans During Construction of DOE's Remedial Action at inactive Uranium Mill Tailings Sites," January 1989.
11
- r APPENDlX A i
NRC SITE VISITS TO THE MEXICAN HAT AND MONUMENT VALLEY UMTRA PROJECT SITES DATE SIAFF/ DISCIPLINE EVEP_OSE l
4/21/92 M. Layton/ hydrology Site visit at Monument Valley and Mexican T. -Johnson / surface hydtclogy Hat.
D. Rom /geotech. engineering E. Brummett/ rad. protection M. Hague / project management 11/5/92 T. Johnson / surface hydrology Discuss erosion protection design at A. Mullins/ geology Mexican Hat.
M. Hague / project management 9/2/93 D. Rom /geotech, engineering Construction progress review r.1 Mexican Hat and Monument Valley.
10/27/93 D. Rom /geotech, engineering Construction progress review and discuss T. Johnson / surface hydrology erosion protection design at Moxican Hat.
5/18/94 D. Rom /gentech. engineering Construction progress review and discuss T. Johnson / surface hydrology rock durability issues at Mexican Hat. P!te R. Carlson/ project management visit of Monument Valley, 5/6/96 M. Layton/ hydrology.
Observe reclaimed Monument Valley H. Lefevre/ project management processing site; and observe coinpleted disposal cell and existing seeps at Mexican Hat.
.2/25/97_
T. Johnson / surface hydrology Observe erosion protection at completed Mexican Hat disposal site.
A-1
APPENDJXE UMIRCAIHE EPA STANDARDS Al4D THE PHASED UMTRA PRQ)EQI Title i of the Uranium Mill Tailings Radiation Control Act (UMTRCA) defines the statutory authority and roles of the DOE, the NRC, and the EPA with regard to the remedial action program for inactive uranium mill tailings sites.
The Standards UMTRCA charged the EPA with the responsibility for promulgating remedial action standards for inactive uranium mill sites. The purpose of these standards is to protect the public health and safety and the environment from radiological and non radiological hazards associated with radioactive materials at the sites. UMTRCA required that EPA promulgate these standards by no later than October 1,1982. After October 1,1982, if the EPA had not promulgated standards in final form, DOE was to comply with the standards proposed by EPA under Title 1 of U'/TRCA until such time as the EPA had promulgated its standards in final form.
The final EPA standards were prci..ulgated with an effective date of March 7,1983 (48 FR 602; January 5,1983); see 40 CFR Part 192 Standards for Remedial Actions at inactive Uranium Processing Sites, Subparts A, B, and C. These regulauons may be summanzed as follows:
1.
The disposal site shall h designed to control the tailings and other residual radioactive materials for up to 1000 years, to the extent reasonably achievable, and, in any case, for at least 200 years (40 CFR 192.02(a)).
2.
The disposal site design shall provide reasonable assurance that radon 222 from residual radioactive material to the atmosphere will not exceed an average release rate of 20 picoeuries per square meter per second, or will not increase the annual average concentration of radon 222 in air, at or above any location outside the disposal site, by more than one half picocurie per liter [40 CFR 192.02(b)).
3, The remedial action shall be conducted so as to provide reasonable assurance that, as a result of residual radioactive materials from any designated processing site, the concentrations of radium 220 in land averaged over any area of 100 square meters shall not exceed the background level by more than 5 picocuries/ gram averaged over the first 15 centimeters of son below the sur'. Se and 15 picoeuries/ gram averaged over 15 centimeter thick layers of soil more than 15 centimeters below the surface (40 CFR 192.12(a)).
4.
The objective of remedial action involving buildings shall be, and reasonable effort shall be made to achieve, an annual average (or equivalent) radon decay product concentration (including background) not to exceed 0.02 WL, and the level of gamma radiation shall not exceed the background level by more than 20 micro roentgens per hour
[40 CFR 192.12(b)).
5.
The portion of the EPA standards dealing with groundwater requirements, 40 CFR 192.20(a)(2)-(3) were remanded by the Tenth Circuit Court of Appeals on September 3,1985. Based on this court decision, EPA was directed to promulgate new groundwater standards. EPA proposed these standards in the form of revisions to Subparts A C of 40 CFR Part 192 in September 1987, and the final groundwater standards were promulgated January 11,1995.
B1 l
Before the groundwater standards were final, as mandated by Section 108(a)(3) of UMTRCA, the remedial action at the inactive uranium processing sites were to comply with EPA's proposed standarda until such time as the final standards are promulgated. DOE performed remedial action at the inactive processing sites in accordance with NRC's concurrence with the remedial action approach based on the proposed EPA groundwater standards (52 FR 36000; September 24,1987). Delaying implementation of the remedial action program would be inconsistent with Congress' intent of timely completion of the program. Modifications of disposal sites after completion of the remedial action to comply with EPA's final groundwater protection standards may be unnecessarily compleated and expensive and may not yield commensurate benefits in terms of human and environmental protection. Therefore, the Commission believes that sites where remedial action has been essentially completed prior to EPA's promulgation of final groundwater standards, will not be impacted by the final groundwater standards promulgated January 11,1995. Although additional effort may be appropriate to assess and clean up contaminated groundwater at these sites, the existing designs of the disposal sites should be considered sufficient to provide long term protection against future groundwater contamination. NRC does not view UMTRCA as requiring the reopening of those sites that Mve been substantially completed when NRC concurred with the selection of remedial action in accordance with applicable EPA standards, proposed or otherwise in place at the time such NRC concurrence was given.
DOE Selection (Design) Phase For each site, UMTRCA requires that DOE select a plan of remedial action that will satisfy the EPA standards and other applicable laws and regulations, and with which the NRC will concur.
For each site, this phase includes preparation by DOE of an Environmental Assessment or an EnvironmentalImpact Statement, and a Remedial Action Plan (RAP). The RAP is structured to provide a comprehensive understanding of the remedial actions proposed at that site and contains specific design and construction requirements. To complete the first phase, NRC and the appropriate State or indian tribe will review the RAP and then concur that the RAP will meet the EPA standards.
The Performance (Construction) Phase in this phase the actual remedial action (which includes decontamination, decommissioning, and reclamation) at the site is done in accordance with the RAP. The NRC and the State / indian tribe, es applicable, must concur in any changes to the concurred in plan that arise dur.og construction. At the completion of remedial action activities at the site, NRC concurs in DOE's determination that the activities at the site have been completed in accordance with the approved plan. Prior to licensing (the next phase), title to the disposed tailings and contaminated materials must be transferred to the United States and the land upon which they are disposed of must be in Federal custody to provide for long term Fedaral control. Disposal sites on Indian land will remain in the beneficial ownership of the Indian tribe.
NRC concurrence in the DOE determination that remedial action at a processing site has been accomplished in accordance with the approved plan may be accomplished in two steps where i
residual radioactive material is not being moved from the processing site to a different disposal j
site. The Uranium Mill Tailings Remedial Action Amendments Act of 1988 allows for a two-step i
approach for Title I disposal sites. The Amendments Act will allow DOE to do all remedial actions, other than groundwater restoration, for the first step of closure and licensing. The second step, which can go on for many years, will deal with existing groundwater restoration.
When groundwater restoration is completed, the Long Term Surveillance Plan required under B2
l the licensing phase will be appropriately amended. For sites that are being moved, licensing will occur in one step. There is no groundwater restoration at the disposal site and the processing site will not be licensed after completion of remedial action.
The Licensing Phase Title I of UMTRCA further requires that, upon completion of the remedial action program by DOE, the permanent Qosal sites be cared for by the DOE or other Federal agency designated by the President, under a license issued by the Commission. DOE will receive a generallicense under 10 CFR Part 40.27 following: (1) NRC concurrence in the DOE determination that the disposal site has been properly reclaimed, and (2) the formal receipt by NRC of an acceptable Long Term Surveillance Plan (LTSP). NRC concurrence with DOE's performance of the remedial action indicates that DOE hs. demonstrated that the remedial action complies with the provisions of the EPA standards in 40 CFR part 192, Subparts A, B, and C. This NRC concurrence may be completed in two steps as discussed above. There is no termination date for the generallicense.
Public involvement has been and will continue to be provided through DOE's everall remedial action program for Title i sites. The local public will have an opportunity to comment on the remedial action or closure plans proposed and implemented by DOE and to raise concerns regarding final stabilization and the degree of protection achieved. NRC fully endorses State / Indian tribe and public input in all stages of the program. At the time the LTSP is submitted, the NRC will consider the need for a public meeting in response to requests and public concerns.
The Surveillance and Monitoring Phase in this phase, DOE and NRC periodically inspect the disposal site to ensure its integrity. The LTSP will require the DOE to make repairs, if needed.
One of the requirements in the EPA standards is that control of the tailings should be designed to be effective for up to 1000 years without active maintenance. Although the design of the stabilized pile is such that reliance on active maintenance should be minimized or eliminated, the NRC license will require emergency repairs as necessary. In the event that significant repairs are necessary, a detsrmination will be made on a site specific basis regarding the need for additional National Environmental Policy Act actions, and health and safety considerations based on 10 CFR Pads 19,20, and 21.
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CERTIFICATION
SUMMARY
URANIUM MILL TAILINGS REMEDIAL ACTION PROJECT MEXICAN IIAT, UTAll AND MONUMENT VALLEY, ARIZONA The U. S. Department of Energy certifies that the remedial actions performed in Mexican liat, Utah, and Monument Valley, Arizona, for the Uranium Mill Tailings Remedial Action Project are complete and meets all design criteria and technical specifications outlined in the surface Remedial Action Plan, as required under Public Law 95-604 The undersigned request that the U.S. Nuclear Regulatory Commission concur in this certification.
U S. DEPARTMENT OF ENERGY U.S. DEPARTMENT OF ENERGY
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Juan tiliams
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Co ractingOfficer Director C intracts and Procurement Division Environmental Restoration Division 9
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Gub. I 7,1977 Date I
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The U.S. Nuclear Regulatory Commission hereby concurs with the U.S. Depanment of Energy's completion of surface remedial action for the Uranium Mill Tailings Remedial Action Projects located in Mexican llat, Utah, and Monument Valley, Arizona.
U S. NUCLEAR REGULATORY COMMISSION O -.,-
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Joseph J. Ilolonich, Chief Uranium Recovery Branch Division of Waste Management Office of Nuclear Materials Safety and Safeguards whY /d lD Date '
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0 CERTIFICATION
SUMMARY
URANIUM MILL TAILINGS REMEDIAL ACTION PROJECT MEXICAN IIAT, UTAll AND MONUMENT VAll.EY, ARIZONA The U. S. Department of Energy certifies that the remedial actions performed in Mexican liat, Utah, and Monument Valley, Arizona, for the Uranium Mill l ailings Remedial Action Project are complete and meets all design criteria and technical specifications outlined in the surface Remedial Action Plan, as required under Public Law 95-604. The undersigned request that the U.S. Nuclear Regulatory Commission concur in this certification.
U S. DEPARTMENT OF ENERGY U.S. DEPARTMENT OF ENERGY
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C tracting Ollicer Director ontracts and Procurement Disision Ensironmental Restoration Disision
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Ud lil, /997 Date
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Date
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4 The U.S. Nuclear Regulatory Commission hereby concurs with the U S. Department of Energy's completion of surface remedial action for the Uranium Mill Tailings Remedial Action Projects located in Mexican llat, Utah, and Monument Valley, Arizona U S. NUCLEAR REGULATORY COMMISSION i
Joseph J31onich, Chief Uranium Recovery Branch Disision of Waste Management Ollice of Nuclear Materials Safety and Safeguards
/b /?D Date '