E6-11833. Notice of Availability of Environmental Assessment and Finding of No Significant Impact Concerning the ExxonMobil Refining and Supply Company License Amendment Request for Alternate Groundwater Protection Standards at the Highland ...

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Notice of availability of Environmental Assessment and Finding of No Significant Impact.

FOR FURTHER INFORMATION CONTACT:

Myron Fliegel, Senior Project Manager, Fuel Cycle Facilities Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material Safety and Safeguards, U.S. Nuclear Regulatory Commission, Washington, DC 20555. Telephone: [phone]; fax number: [phone]; e-mail: [e-mail].

SUPPLEMENTARY INFORMATION:

I. Introduction

The U.S. Nuclear Regulatory Commission (NRC) is considering the issuance of a license amendment to Source Materials License SUA-1139 issued to ExxonMobil Corporation (ExxonMobil, the licensee), to establish alternate groundwater protection standards for chromium, uranium, selenium, and nickel at the Highland Reclamation Project (Highland), located in Converse County, Wyoming. Pursuant to the requirements of 10 CFR part 51 (Environmental Protection Regulations for Domestic Licensing and Related Regulatory Functions), the NRC has prepared an Environmental Assessment (EA) to evaluate the environmental impacts associated with ExxonMobil's proposed modifications to the groundwater protection standards for the Highland site. Based on this evaluation, the NRC has concluded that a Finding of No Significant Impact (FONSI) is appropriate for the proposed licensing action. The license amendment will be issued following the publication of this Notice.

II. Environmental Assessment

Introduction

By letter dated January 16, 2006, ExxonMobil submitted an application to the NRC, requesting an amendment to Source Materials License SUA-1139 for the Highland Reclamation Project to modify the groundwater protection standards for chromium, uranium, selenium, and nickel at the designated point of compliance (POC) wells in the license. In this regard, the NRC's groundwater protection standards in 10 CFR part 40, Appendix A, Criterion 5B(5) specify the following:

5B(5)—At the point of compliance, the concentration of a hazardous constituent must not exceed:

(a) The Commission approved background concentration of that constituent in the groundwater;

(b) The respective value given in the table in paragraph 5C if the constituent is listed in the table and if the background level of the constituent is below the value listed; or

(c) An alternate concentration limit established by the Commission.

Further, groundwater monitoring to comply with the standards established in accordance with the above specifications is required by Criterion 7A.

Consistent with the requirements of Criterion 7A, License Condition (LC) 33 of ExxonMobil's Source Materials License SUA-1139 specifies that a groundwater monitoring program must be conducted at the Highland site and ExxonMobil must comply with the established groundwater protection standards at the designated POC wells for the constituents of interest, including chromium, uranium, selenium, and nickel. For chromium and selenium, the groundwater protection standards for the Highland site were set at the Maximum Contaminant Levels (MCLs) for those constituents in the table in paragraph 5C of 10 CFR part 40, Appendix A. The MCLs for the constituents listed in the table in paragraph 5C were derived from the MCLs established for those constituents in the U.S. Environmental Protection Agency (EPA) National Primary Drinking Water Regulations (NPDWRs). For uranium and nickel, the groundwater protection standards were based on the NRC approved background concentrations for those constituents in the groundwater. However, in the years subsequent to the establishment of the groundwater protection standards in ExxonMobil's license, the MCLs for chromium and selenium in the EPA's NPDWRs have been modified and a new MCL for uranium has been promulgated. The former MCL for nickel in the NPDWRs (0.1 parts per million) was remanded in 1995, and there is now no EPA legal limit on the amount of nickel in drinking water.

In light of the aforementioned changes to the EPA's NPDWRs, ExxonMobil has requested that Source Materials License SUA-1139 be amended to reflect the current MCLs for chromium, selenium, and uranium in the NPDWRs. In this regard, the staff notes that the table in paragraph 5C of 10 CFR part 40, Appendix A, has not yet been revised to reflect the current NPDWRs for chromium, selenium, and uranium. Additionally, even though the MCL for nickel has been remanded and nickel is no longer listed as a regulated contaminant in the NPDWRs, ExxonMobil has requested that its license be modified to incorporate the former MCL for nickel as the groundwater protection standard. In this regard, the NRC notes that the EPA believed that the 0.1 parts per million level for nickel would not cause any potential health problems. In accordance with the requirements of 10 CFR part 40, Appendix A, Criterion 5B(5)(c), the requested modifications to ExxonMobil's license would establish alternate concentration limits for chromium, uranium, selenium, and nickel for implementation of a groundwater corrective action program in the event a concentration limit is exceeded for any of those constituents at the designated POC wells. Correspondingly, the requested license modifications have the potential for impacting the quality of the groundwater offsite. The NRC staff has evaluated ExxonMobil's request and has developed this EA to support the detailed technical review of ExxonMobil's proposed modifications to the groundwater protection standards for the Highland site, in accordance with the requirements of 10 CFR part 51.

The Proposed Action

The proposed action is to amend NRC Source Materials License SUA-1139 to reflect the current groundwater protection standards for chromium, uranium, and selenium in the EPA NPDWRs and incorporate the former groundwater protection standard for nickel, even though it is no longer a regulated constituent. ExxonMobil's objective in this proposal is to establish groundwater protection standards for the Highland site that are appropriate and consistent with the current standards for chromium, uranium, and selenium in the EPA NPDWRs and conservative with respect to the retention of a groundwater protection standard for nickel. Specifically, ExxonMobil has proposed the following modifications to the groundwater protection standards in LC 33 of the Highland license: Chromium would change from 0.05 milligrams per liter (mg/L) to 0.10 mg/L (the current MCL); uranium would change from the former radiotoxicity value of 0.43 picocuries per liter (pCi/L) (0.00065 mg/L) to the new chemical toxicity MCL of 0.03 mg/L (20 pCi/L); and selenium would change from 0.01 mg/L to 0.05 mg/L (the current MCL). The standard for nickel would change from the 0.02 mg/L background concentration in the groundwater to 0.1 mg/L (the equivalent of the EPA's former MCL of 0.1 parts per million).

The Need for the Proposed Action

The purpose of the proposed action is to establish groundwater protection standards for the Highland site which are consistent with the present or former EPA NPDWRs and correspondingly reflective of the understanding of the health and environmental impacts of specific contaminants in drinking water. With this EA, the NRC is fulfilling its responsibilities under the Atomic Energy Act to make a decision on a proposed license amendment for groundwater protection standards that ensures protection of public health and safety and the environment.

The Environmental Impacts of the Proposed Action

The staff has evaluated the potential impacts associated with ExxonMobil's proposed modifications to the groundwater protection standards for chromium, uranium, selenium, and nickel at the Highland site and determined that those effects are limited to the potential public health and safety impacts related to possible degradation of offsite groundwater quality and water utilization. In this case, the bounding or controlling environmental impact is related to the potential use of that groundwater for drinking water purposes. However, as noted in ExxonMobil's amendment request, ExxonMobil has proposed to establish onsite groundwater protection standards for chromium, uranium, and selenium at the designated POC wells that are reflective of the current EPA NPDWRs for those contaminants. Additionally, even though the drinking water standard for nickel was remanded more than a decade ago, ExxonMobil has proposed a conservative health based standard for nickel that is consistent with the former MCL (0.1 mg/L) for that constituent. Conceptually, the EPA has determined that the drinking water limits in the NPDWRs pose acceptable hazards. The NPDWRs effectively protect the public health and safety and the environment by limiting the concentrations of contaminants in drinking water. The NRC finds that ExxonMobil has proposed onsite groundwater protection standards for chromium, uranium, selenium, and nickel that are adequately protective of public health and safety and the environment. Groundwater protection standards that are consistent with EPA's NPDWRs also satisfy the intent of 10 CFR part 40, Appendix A, Criterion 5B(5)(b), recognizing the outdated table in paragraph 5(C). Further, in the event that any of the proposed groundwater protection standards for chromium, uranium, selenium, and nickel are exceeded, ExxonMobil's license specifies that a corrective action program must be proposed with the objective of returning the concentrations of those constituents to the values mandated in the license. These requirements will minimize the potential for any adverse impacts and further ensure the protection of public health and safety and the environment.

Alternatives to the Proposed Action

As the only reasonable alternative to the proposed action, the staff has considered denial of ExxonMobil's request (i.e., the no action alternative). Denial of ExxonMobil's request would result in no change in environmental impacts. The environmental impacts of the proposed action and the alternative action are similar, though, since both would be protective of offsite sources of drinking water. However, the no action alternative would leave the groundwater protection standards in ExxonMobil's license unnecessarily restrictive and out-of-date with respect to the current EPA NPDWRs and the present understanding of the potential health effects of certain contaminants in drinking water.

Agencies and Persons Consulted

This EA was prepared by NRC staff (Myron Fliegel, Senior Project Manager) and coordinated with the following agency:Wyoming Department of Environmental Quality (WDEQ). NRC staff provided a draft of its EA to WDEQ for review. In electronic correspondence dated June 13, 2006, the WDEQ indicated that it did not have any comments on the draft EA.

The NRC staff has determined that the proposed action will not affect listed species or critical habitat. Therefore, no further consultation is required under Section 7 of the Endangered Species Act. Likewise, the NRC staff has determined that the proposed action is not the type of activity that has potential to cause effects on historic properties. Therefore, no further consultation is required under Section 106 of the National Historic Preservation Act.

Conclusion

The NRC staff has prepared this EA in support of the proposed license amendment to modify the groundwater protection standards for the Highland site. Based upon the analysis contained in this EA, the staff concludes that proposed action will not have a significant effect on public health and safety and the environment.

III. Finding of No Significant Impact

On the basis of this EA, NRC has concluded that there are no significant environmental impacts from the proposed license amendment and has determined that the proposed action does not warrant the preparation of an environmental impact statement. Accordingly, it has been determined that a Finding of No Significant Impact is appropriate.

IV. Further Information

Documents related to this action, including the application for amendment and supporting documentation, are available electronically at the NRC's Electronic Reading Room at http://www.nrc.gov/​reading-rm/​adams.html. From this site, you can access the NRC's Agencywide Document Access and Management System (ADAMS), which provides text and image files of NRC's public documents. The ADAMS accession numbers for the documents related to this notice are as follows:

1. ExxonMobil Refining and Supply. Letter dated January 16, 2006, from D. Burnham, ExxonMobil, to G. Janosko, NRC, requesting amendment to License Condition 33 of Source Materials License SUA-1139 for the Highland Reclamation Project. (ML060260421)

2. E-mail correspondence dated February 7, 2006, from M. Fliegel, NRC, to D. Burnham, ExxonMobil, acknowledging receipt of the ExxonMobil January 16, 2006, license amendment request. (ML060400048)

3. E-mail correspondence dated June 13, 2006, from M. Thiesse, WDEQ, to M. Fliegel, NRC, indicating that WDEQ had no comments on the draft EA. (ML061670212)

If you do not have access to ADAMS or if there are problems in accessing the documents located in ADAMS, contact the NRC's Public Document Room (PDR) Reference staff at 1-800-397-4209, 301-415-4737, or by e-mail to [e-mail].

These documents may also be viewed electronically on the public computers located at the NRC's PDR, O1 F21, One White Flint North, 11555 Rockville Pike, Rockville, MD 20852. The PDR reproduction contractor will copy documents for a fee.

Dated at Rockville, Maryland, this 18th day of July, 2006.

For the Nuclear Regulatory Commission.

Myron Fliegel,

Senior Project Manager, Fuel Cycle Facilities Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material Safety and Safeguards.