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Decommissioning Projects - Wyoming, USA

(last updated 25 Jun 2014)

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WYOMING


Exploration pits in Bighorn Canyon National Recreation Area (Montana/Wyoming)

> See also Montana

 

Bighorn Canyon to clean up exploratory uranium mines

A draft environmental study examines what will be required to clean up more than 350 old uranium exploration pits in Bighorn Canyon National Recreation Area. The pits range from less than 0.01 acre [40 m2] to 5.6 acres [2.3 ha] and are left over from the uranium boon of the 1950s, recreation area officials said. Because of the arid climate, little natural recovery has occurred at the sites. The National Park Service is planning to re-countour and reseed the sites over about 10 years. (Casper Star-Tribune June 4, 2003)

Bighorn Canyon National Recreation Area external link

> Download Draft Environmental Assessment (May 2003) external link (892k PDF)

Comments on the study may be submitted by July 15, 2003.


Crooks Gap Uranium Mining District

Green Mountain Ion-Exchange (GMIX) Site

NRC Docket No. 40-8971 (U.S. ENERGY CORP)
NRC Source Material License No. SUA-1524

Aerial View: Google Maps external link new window · MSRMaps external link new window

 

NRC terminates Green Mountain Ion-Exchange Site license

By letter dated March 27, 2003, the U.S. NRC terminated Source Material License No. SUA-1524.

 

Notice of Request to Terminate the License for the Green Mountain Ion-Exchange Site

By letter dated October 24, 2002, U.S. Energy Corp. provided to NRC a completion report for the decommissioned Green Mountain Ion Exchange (GMIX) site and a request to terminate the license for the site.
"Green Mountain Ion Exchange (GMIX) facility was an ion exchange facility that removed uranium from mine water and is located in Fremont County, Wyoming south of Jeffrey City, Wyoming in the Crooks Gap Uranium Mining District. The facility consisted of; one main, 40 foot by 60 foot [12.2m x 18.3m], building; one, 24 foot by 24 foot [7.3m x 7.3m], auxiliary water treatment building (BaCl building); primary settling pond (Roberts No.3 Pond) approximate surface area of disturbance is 2.4 acres [1 ha]; and secondary settling pond (Roberts No.2 Pond) with approximate surface area of disturbance 3.9 acres [1.6 ha]."

"The current status is that all 11e(2) material has been removed to Sweetwater Mill tailings facility, NRC license No. SUA-1350, with soil verification sampling completed."
(Completion Report Oct. 24, 2002)

On Jan. 3, 2003, NRC published a "Notice of Request to Terminate Source Material, License SUA-1524, for the Green Mountain Ion-Exchange Site in Fremont County, WY and Opportunity to Provide Comments and to Request a Hearing"
Federal Register, Jan. 3, 2003 (Vol. 68, No. 2), p. 392-393 (download full notice external link).

There were no comments or requests for a hearing in response to this FR notice.


Western Nuclear Split Rock uranium mill site, Wyoming

NRC Docket No. 40-1162 (WESTERN NUCLEAR, INC., LAKEWOOD, CO)
NRC Source Material License No. SUA-56

NRC Facility Info external link
Aerial view: Google Maps external link new window · MSRMaps external link new window

 

NRC requests response on increasing contaminant concentrations in groundwater at Split Rock uranium mill tailings site, exceeding even relaxed groundwater standards

On Sep. 11, 2013, NRC issued a Request for Additional Information to Western Nuclear Inc. [WNI]
"In 1999 WNI requested ACLs [alternate concentration limits] for several regulated constituents on the Split Rock site, which NRC subsequently approved. In support of that application WNI presented ground water models showing that contaminant concentrations generally decrease from the POC [point of compliance] wells to the IC [institutional controls] boundaries, would not reach to boundaries in less than 1000 years, and would be within acceptable concentrations thereafter.
The model predictions do not explain the data collected over most of the last decade, showing increases in several constituents in wells downstream of the POCs. In addition to varying significantly from the model predictions, the current condition is not in compliance with NRC regulations, such as Criterion 5(B)1 of Appendix A. [...]" (emphasis added)

"In 1999 Western Nuclear Inc. (WNI) requested an alternate concentration limit (ACL) for nitrates in the SW Valley of 70.7 mg/l. NRC approved the request in 2006. Wells SWAB-2 and SWAB-1R are in the uppermost aquifer and are downstream of the point of compliance (POC) well for the SW Valley. Subsequent data for nitrate concentrations in SWAB-2 are greater than 300 mg/l, and in SWAB-1R are about 100 mg/l. These concentrations exceed the ACL."

"In 1999 WNI requested to use institutional controls (ICs) on private properties in lieu of corrective actions to limit potential exposure of humans to contamination from the Split Rock Site. The bases for this approach and the specification of the boundaries for the institutional controls are in the ground water and transport model. In its application, WNI stated that '... present concentrations have been demonstrated to be decreasing in a stable manner.'
However, recent data shows increasing concentration of nitrates in SWAB-2 and increasing aluminum, ammonia, cadmium, and nickel in Well-4R. Selenium has also shown periodic spikes in the NW Valley. Therefore, the statements in the application and results of ground water model predictions are not consistent with recent data, and do not appear to support limiting exposure at the current IC boundary."

> Download NRC letter and Request for Additional Information, Sep. 11, 2013 external link

Draft Long-Term Surveillance Plan released for the Split Rock Disposal Site

On April 12, 2012, DOE submitted the Draft Long-Term Surveillance Plan for the Split Rock Disposal Site for NRC review.
> Download: Draft Long-Term Surveillance Plan for the Split Rock, Wyoming, (UMTRCA Title II) Disposal Site, Fremont County, Wyoming, LMS/SPR/S02613-0.0, April 2012 external link (ADAMS Acc. No. ML12109A081)

NRC approves relaxed groundwater standards at Western Nuclear, Inc.'s Split Rock uranium mill tailings site

On December 1, 2008, Western Nuclear, Inc. (WNI) submitted a request to amend License Condition (LC) 74. WNI also submitted a separate amendment request dated March 9, 2009 to establish standards for constituents that must be monitored but for which there are no associated standards.
WNI requested multiple changes to LC 74B. Specifically, it requested For LC 74D, WNI requested The NRC approved the requested license amendments on Feb. 24, 2010.

> Download Technical Evaluation Report for Western Nuclear, Inc., Split Rock mill site, Jeffrey City, WY, Feb. 24, 2010 external link (ADAMS Acc. No. ML092800206)

NRC issues Environmental Assessment and Finding of No Significant Impact for relaxed groundwater standards at Western Nuclear, Inc.'s Split Rock uranium mill tailings site

WNI has requested that an alternate concentration limit (ACL) be set for selenium at the point of compliance wells equal to 0.05 mg/L. This requested selenium value is equal to the U.S. Environmental Protection Agency's (EPA's) maximum contaminant level (MCL) for selenium in drinking water. WNI has also requested that natural uranium trigger levels for licensee action at the point of exposure be set at background levels, specifically 0.087 mg/L for the Split Rock aquifer and 0.044 mg/L for the flood-plain aquifer. The request excludes one well (Well SWAB-32), where the existing standard will not change.
Federal Register: February 5, 2010 (Volume 75, Number 24) p. 6067-6068 (download full text external link)
> Download Final Environmental Assessment, January 28, 2010 external link (ADAMS Acc. No. ML092780271)

NRC announces Opportunity To Request a Hearing concerning indirect change of ownership for Split Rock uranium mill tailings site

Notice of application from Western Nuclear Inc., for consent to indirect change of control (from Phelps Dodge Corporation to Freeport-McMoRan Copper & Gold, Inc.) with respect to Materials License SUA-56, Opportunity To Provide Comments and To Request a Hearing
A request for a hearing must be filed by November 2, 2009.

Federal Register: October 13, 2009 (Volume 74, Number 196) p. 52510-52512 (download full text external link)

DOE raises concern over likely future exceedance of proposed relaxed groundwater standards at Split Rock uranium mill tailings site, requests further relaxation...

In comments submitted to the NRC on Sep. 14, 2009 (ADAMS Acc. No. ML092680734 external link), the Department of Energy (DOE) raised concerns over the proposed alternate concentration limit (ACL) for selenium and the proposed revision to the trigger value for uranium.

DOE's comments refer to a draft Environmental Assessment dated Aug. 12, 2009 (unpublished), that was prepared by NRC in response to a license amendment request submitted by Western Nuclear, Inc. on Dec. 1, 2008 (ADAMS Acc. No. ML083380453 external link).
On April 1, 2009, NRC had requested additional information (ADAMS Acc. No. ML090820330 external link and ML090820357 external link) that WNI submitted on June 16, 2009 (unpublished).

NRC issues Environmental Assessment and Finding of No Significant Impact for relaxed groundwater standards at Western Nuclear, Inc.'s Split Rock uranium mill tailings site

Notice of Availability of Environmental Assessment (EA) and Finding of No Significant Impact (FONSI) for License Amendment for Western Nuclear, Inc., Jeffrey City, WY

The purpose of the proposed amendment is to authorize the establishment of ACLs instead of ground water protection standards for six constituents at the Licensee's Jeffrey City, Wyoming, facility. Specifically, this amendment will establish ACLs for ammonia, manganese, molybdenum, nitrate, radium-226 and -228, and natural uranium. This amendment will also require the Licensee to establish institutional controls on all properties within the long-term surveillance boundary to preclude domestic ground water use. On October 29, 1999, the Licensee requested that NRC approve the proposed amendment.

Federal Register: September 6, 2006 (Volume 71, Number 172) p. 52589-52590 (download full text external link)
> Download Environmental Assessment for Amendment to Source Materials License SUA-56 Ground Water Alternate Concentration Limits, August 2006 external link (ADAMS Accession No. ML062130316)

In the EA, NRC discusses various groundwater treatment alternatives, not including permeable reactive barriers, though. The alternatives discussed are dismissed for reasons of inefficiency and of excessive cost. In approving WNI's preferred alternative, NRC permits the contamination of clean groundwater by the progressing contaminant plume and accepts that drinking water wells in the Red Mule area will become unsuitable for domestic use in the future.

On September 28, 2006, NRC issued the requested license amendment.

Western Nuclear requests permission for cessation of active groundwater restoration at Split Rock site, though standards not met

By letter dated Aug. 13, 2004, Western Nuclear, Inc. (WNI) requests that the Nuclear Regulatory Commission (NRC) grant WNI a license amendment permitting cessation of its active ground water corrective action program (GWCAP) at its Split Rock site in Jeffrey City, Wyoming.
The GWCAP involves pumping and evaporation of site groundwater containing contaminants seeped from the former uranium mill site and/or the uranium mill tailings pile. Although pumping is ongoing since 1990, groundwater quality still does not meet NRC standards, and WNI does not believe that continued pumping will result in further improvement of site groundwater quality.
(Law Offices of Anthony J. Thompson, P.C., letter to NRC dated Aug. 13, 2004, see also: Law Offices of Anthony J. Thompson, P.C., letter to NRC dated May 26, 2005)
By letter dated July 6, 2005, WNI's request was withdrawn.

Western Nuclear wants to prohibit groundwater use rather than prevent contaminant plume dispersion

The modeling projections of Western Nuclear, Inc. (WNI) illustrate that groundwater contamination will impact water sources under privately held land within 100-200 years in the Red Mule area, which is a cluster of ranches/homes with domestic water wells located approximately 1-2 miles southeast of the Split Rock site.

View animation of groundwater plume new window (70k)

WNI's preferred alternative "Pathway Elimination + Institutional Control" (!) would prohibit groundwater use for drinking water in an area of 3,635 acres (1,471 ha) that will be affected by the dispersing contaminant plume within 1000 years. Well owners are to be supplied with alternate drinking water supplies, instead. This area is much larger and in addition to the area of 1,640 acres (664 ha) used for stabilizing the uranium mill tailings pile itself. The costs for this preferred alternative would be $114,000 only, rather than the $17.9 - 117 million for the other alternatives considered.
(see: Minutes From The Groundwater Corrective Action Plan Meeting On September 22, 1999, U.S. NRC, Nov. 1, 1999, available on ADAMS external link)

On March 7, 2003, WNI filed a Supplemental Groundwater Modeling Report, indicating that the area affected by the groundwater plume after 1000 years would be smaller than previously assumed. Based on the results of the new predictions, WNI modified the proposed long-term care boundary for the site and its surroundings.

View revised animation of groundwater plume new window (153k)


Gas Hills North disposal site (ex Pathfinder Mines Lucky Mc uranium mill site), Fremont County, Wyoming

NRC Docket No. 40-2259 (PATHFINDER MINES CORP., RIVERTON, WY)
NRC Source Material License No. SUA-672

On July 24, 2012, Ur-Energy Inc. announced that is acquiring Lucky Mc from Areva.
> View deposit data
NRC Facility Info external link   aerial view external link

 

NRC approves transfer of Lucky Mc license from Pathfinder Mines to Areva NC

On June 27, 2013, NRC approved the transfer of the Lucky Mc license from Pathfinder Mines Corporation (PMC) to its parent company Areva NC Inc. PMC is a wholly owned subsidiary of Cogema Resources, Inc.. Cogema Resources, Inc. is a wholly owned subsidiary of Areva NC Inc. To facilitate the sale of PMC to Ur-Energy USA Inc., PMC desired to transfer the Lucky Mc license to its parent Areva NC Inc.

 

Uranium concentrations in groundwater exceed ACL standard at Gas Hills North (formerly Lucky Mc) disposal site

"The U.S. Department of Energy, Office of Legacy Management (DOE-LM) wishes to formally request assistance from the U.S. Nuclear Regulatory Commission (NRC) regarding uranium concentrations recently reported above the alternate concentration limit (ACL) in trend well AL-1 at the Gas Hills North (UMTRCA Title II) Disposal Site, Fremont County, Wyoming. Trend well AL-1 is downgradient of the point of compliance (POC) well T1-12. DOE-LM obtained this information from the licensee's Semi-Annual Groundwater Monitoring Report for Lucky Mc Mine (i.e., the Gas Hills North site) dated February 3, 2012. This condition appears to violate Criterion 5B(1) of 10 CFR 40, Appendix A, which states ''Hazardous constituents entering the ground water from a licensed site must not exceed the specified concentration limits in the uppermost aquifer beyond the point of compliance during the compliance period.''

The ACL for uranium at the POC is 1.7 milligrams per liter (mg/L). DOE-LM noted that uranium concentrations were reported just above the ACL in trend well AL-1 in both the third and fourth quarters of 2011. Uranium concentrations in well AL-1 were 1.76 mg/L in the third quarter and 2.42 mg/L in the fourth quarter. These concentrations represent a significant increase over the May 2010 observation of 0.4 mg/L (refer to Figure 10 in the monitoring report). Sulfate, chloride, and total dissolved solids concentrations are also increasing; these three analytes do not have ACLs. DOE-LM believes the monitoring results indicate that processing-related groundwater contamination is moving toward the site boundary, whereas the ACL application assumed that contamination would attenuate to levels less than the ACL at locations downgradient of the POC." [emphasis added]
(U.S. DOE letter to NRC dated Feb. 29, 2012, ADAMS Acc. No. ML12065A005 external link)

In a Technical Review dated Sep. 4, 2012, NRC staff concludes that "it is not likely that leakage of impacted groundwater from the tailings impoundment is the source of these elevated levels.". (ADAMS Acc. No. ML12248A210 external link)

 

DOE issues Long-Term Surveillance Plan for the Gas Hills North (formerly Lucky Mc) Disposal Site

> Download: Long-Term Surveillance Plan for the Gas Hills North (UMTRCA Title II) Disposal Site, Fremont County, Wyoming, December 2011: Main Document and Appendix A external link (42M PDF) · Appendices B-E external link (15M PDF)

 

NRC approves reclamation performed on Lucky Mc uranium mill tailings

On September 27, 2006, the U.S. Nuclear Regulatory Commission (NRC) determined that the reclamation of the Lucky Mc uranium mill tailings site was performed in accordance with the requirements.

 

Pathfinder requests 2-year delay for completion of Lucky Mc uranium tailings cover

Federal Register: March 4, 2003 (Volume 68, Number 42) p. 10275 (download full text external link)
"The U.S. Nuclear Regulatory Commission (NRC) has received, by letter dated December 5, 2002, as supplemented by an e-mail received February 3, 2003, a request from Pathfinder Mining Company to amend License Condition (LC) 61A(3) and 61B(1) of Source Material License SUA-672 for the Lucky Mc Site. The license amendment request proposes to modify LC 61A(3) to change the completion date for radon barrier placement to December 31, 2004, a delay of two years, and to modify LC 61B(1) to change the target completion date for the erosion protection placement to December 31, 2004, a delay of two years."

A request for a hearing must be filed within 30 days of March 4, 2003.

 

NRC to approve relaxed groundwater standards for Pathfinder Lucky Mc mill site

On December 20, 2000, Pathfinder Mines applied for the following alternate concentration limits (ACL) in groundwater at its Lucky Mc uranium mill site:

Constituents STD ACL (at POC) POE
Uranium [mg/l] 0.11 1.70 1.17
Selenium [mg/l] 0.01 1.10 0.26
Nickel [mg/l] 0.09 0.85 0.15
Ra-226 + Ra-228 [pCi/l] 5.0 7.50 5.60
Cadmium [mg/l] 0.01 0.02 0.01
Beryllium [mg/l] 0.05 0.07 0.05
STD = Current standards, ACL = Alternate Concentration Limit, POC = Point of Compliance, POE = "Point of Exposure"

On September 9, 2002, NRC staff issued its "Draft Environmental Assessment for the Pathfinder Mine Corporation’s Lucky Mc uranium mill tailings site, Gas Hills region of Wyoming", concluding "that the environmental impacts associated with the proposed action are not significant and therefore do not warrant denial of the license amendment request."

Under the current program, a total of 197 million gallons [746,000 m3] of water has been pumped from the aquifer and 193 million gallons [731,000 m3] of fresh water has been injected through 2001. Also, approximately 217 million gallons [821,000 m3] of water have been pumped from the tailings.

On Dec. 12, 2002, NRC issed the "Environmental Assessment for the Pathfinder Mine Corporation's Lucky Mc uranium mill tailings site, Gas Hills region of Wyoming".

On Dec. 18, 2002, NRC published a related Federal Register notice :
Federal Register, Dec. 18, 2002 (Vol. 67, No. 243), p. 77529-77530 (download full notice external link).
A request for a hearing must be filed within 30 days of Dec. 18, 2002.

On Dec. 20, 2002, NRC released a Final Finding of No Significant Impact for the Proposed Use of Alternate Concentration Limits:
Federal Register, December 20, 2002 (Volume 67, Number 245), p. 78029-78030 (download full notice external link).
Also, on Dec. 20, 2002, NRC issued the requested license amendment.

 

NRC approves "no action" proposal for contamination at Lucky Mc mill site

Notice in Federal Register, March 17, 1999 (Vol. 64, No. 51), p. 13239-13241 (download full notice external link):
"SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-672, approving Pathfinder Mines Corporation's (PMC's) ``no action'' proposal on cleanup of Reid Draw located downgradient of the Lucky Mc tailings system at Gas Hills, Wyoming. This license currently authorizes PMC to possess byproduct material in the form of uranium waste tailings generated by the licensee's milling operations at the site. In accordance with the requirements of 10 CFR Part 51, an Environmental Assessment (EA) was performed by the NRC staff in support of its review of PMC's Environmental Report (ER) on the status of Reid Draw. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) of ``no action'' proposal on cleanup of Reid Draw."
The proposal concerns an area contaminated from regular releases of excess tailings liquid and from one emergency release of 23 million gallons (87,000 cubic meters). Pathfinder Mines Corporation is 100% owned by COGEMA.


Exxon Highland uranium mill site, Wyoming

NRC Docket No. 40-8102 (EXXON MINERALS CO.)
NRC Source Material License No. SUA-1139

NRC Facility Info external link
Aerial view: Google Maps external link new window · MSRMaps external link new window

 

ExxonMobil requests grossly relaxed groundwater standards for Highland uranium mill tailings site

"In its license amendment application, ExxonMobil requests that NRC approve site and constituent-specific alternate concentration limits (ACL), including the establishment of a new point of compliance (POC) and points of exposure (POE) for 11e.(2) byproduct material constituents seeping into site groundwater from ExxonMobil's reclaimed uranium mill tailings impoundment to the "Southeast Drainage" (i.e., site areas to the south and east of the tailings impoundment) and with a POE and "alternative" for 11e.(2) byproduct material constituents that have seeped to the Highland Pit Lake to the west of the tailings impoundment."

> Download ExxonMobil cover letter May 12, 2011 external link
> Download: Highland Uranium Mine and Millsite, Request for Amendment to Radioactive Materials License SUA-1139 Application to Amend Existing Alternate Concentration Limits, May 2011: Part 1 (Main Text) external link · Part 2 (Figures) external link · Part 3 (Appendix A - E) external link · Part 4 (Appendix E Exhibits 1 - 8) external link · Part 5 (Attachment 1 incl. Appendix A - C) external link · Part 6 (Attachment 2) external link · Part 7 (Attachment 2 Appendix A - C) external link · Part 8 (Attachment 3 w. Appendix A - H) external link

"[...] the current ACLs are identified in License Condition 33B and include the following: [...]
MFG-1 is proposed as a new POC well for the Southeast Drainage groundwater system. This well is located at the toe of the tailings embankment at the head of the Southeast Drainage. [...]
An ACL of 0.7 mg/L for uranium is proposed at Well MFG-1 in the Southeast Drainage. An ACL of 3 mg/L for uranium in Well 175 on the western side of the tailings impoundment is also proposed." [emphasis added]
On Sep. 30, 2011, NRC issued a "Notice of Application from ExxonMobil Corporation, Highland Uranium Mine and Millsite, To Amend Existing Alternate Concentration Limits and Extend the NRC Long-Term Surveillance Boundary With Respect to Materials License SUA-1139" including the opportunity to provide comments, to request a hearing, and to petition for leave to intervene.
Comments must be submitted, or requests for a hearing or leave to intervene must be filed by November 29, 2011.
> Federal Register: September 30, 2011 (Volume 76, Number 190) p. 60935-60937 (download full text external link)
> Access Docket ID NRC-2011-0231 external link

Monitoring well exceeds groundwater protection standard for uranium at Exxon Highland uranium mill tailings deposit

By letter dated Jan. 5, 2011, ExxonMobil notified NRC that "Point of Compliance (POC) Well No. 175 had a uranium concentration of 0.0325 mg/L, which is greater than the License Condition 33B ground water protection standard of 0.03 mg/L for this well." ExxonMobil intends to solve the problem by applying for an Alternate Concentration Limit.

Offsite groundwater contaminant plume identified at Exxon Highland uranium mill tailings deposit

By letter dated Aug. 12, 2008 (ADAMS ML082060075 external link), NRC demanded ExxonMobil to provide a characterization plan to further assess the offsite migration of site-generated radionuclides and chemicals:
"In a letter to the U.S. Nuclear Regulatory Commission (NRC) dated March 18, 2008 (See ADAMS ML080850495 external link), ExxonMobil Refining and Supply Company (ExxonMobil), through its contractor, Arcadis, submitted a statement that "site historical constituents are not a current source of offsite migration, as evidenced by ongoing groundwater sampling at the perimeter of the site." No ground water sampling data was included in this letter. However, the Boner Property Well Report, submitted by Arcadis on May 29, 2008 (See ADAMS ML081630652 external link), clearly shows that there is a ground water plume of site-generated radionuclides and chemicals from the mill tailings cell leaving the ExxonMobil property and impacting the adjacent property.
Because of the above discrepancy, ExxonMobil should provide a characterization plan for the ExxonMobil property to the NRC within 90 days of the receipt of this letter. [...]" [emphasis added]

New study finds Exxon Highland pit lake will not contaminate groundwater

A numerical modeling analysis of the transient groundwater conditions has been conducted in order to address uncertainties relating to the hydrochemical evolution of the Pit Lake at the Highland Mine Site. The results indicate that the Pit Lake will continue to fill until the water level reaches a steady-state elevation of approximately 5,060 feet amsl in the year 2054. Under these conditions, the Pit Lake elevation will remain well below the elevation of the regional discharge area in North Fork Box Creek and its tributaries. As a result, the Pit Lake will not discharge water to the groundwater system and will not become a flow-through system - contrary to previous studies.

Long Term Pit Lake and Groundwater Hydrology at the Highland Mine Site, Final Report, prepared for ExxonMobil by Tetra Tech, May 17, 2007

NRC approves relaxed groundwater standards for Highland mill decommissioning

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 Reclamation Project
Federal Register: July 25, 2006 (Volume 71, Number 142) p. 42137-42139 (download full text external link)

"By letter dated January 16, 2006, ExxonMobil Refining and Supply Company (ExxonMobil) submitted an application to the U.S. Nuclear Regulatory Commission (NRC) staff, requesting an amendment to Source Materials License SUA-1139 for the Highland Reclamation Project (Highland) to modify the groundwater protection standards for chromium, uranium, selenium, and nickel at the point of compliance wells designated in the license. Pursuant to the requirements of 10 CFR Part 51, “Environmental Protection Regulations for Domestic Licensing and Related Regulatory Functions,” the staff has prepared a draft Environmental Assessment (EA) of the ExxonMobil request to evaluate the potential environmental impacts of the proposed action (Enclosure). After a review of the potential impacts of the proposed action, the staff concludes that the proposed action will not have a significant impact on public health and safety and the environment and, as such, a Finding of No Significant Impact is appropriate." [...] (NRC letter to Wyoming Department of Environmental Quality, May 2, 2006)

NRC to approve relaxed groundwater standards for Highland mill decommissioning

Notice in Federal Register Vol. 64, No. 98 (May 21, 1999) p. 27828-27829 (download full notice external link)
"SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) proposes to amend Exxon Corporation's (Exxon's) Source Material License SUA-1139, to allow alternate concentration limits (ACLs) for groundwater hazardous constituents at the Highland uranium mill site in Converse County, Wyoming. An Environmental Assessment (EA) was performed by the NRC staff in accordance with the requirements of 10 CFR part 51. The conclusion of the EA is a Finding of No Significant Impact (FONSI) for this licensing action."
> See also Notice in Federal Register Vol. 64, No. 8 (January 13, 1999) p. 2241 (download full notice external link)


Pathfinder Mines Corp. Shirley Basin uranium mill site, Carbon County

NRC Docket No. 40-6622 (PATHFINDER MINES CORP.)
NRC Source Material License No. SUA-442

> View deposit info
NRC Facility Info external link

> View more recent issues (Pathfinder Mines Corp. Shirley Basin ISL project)

 

NRC approves transfer of Shirley Basin license from Pathfinder Mines to UR-Energy

On June 27, 2013, NRC approved the transfer of the Shirley Basin license from Pathfinder Mines Corporation (PMC) to UR-Energy USA, Inc.

 

Uranium concentration in surface water at Areva's Shirley Basin tailings site exceeds drinking water standard

The uranium concentration in surface water at the Point of Exposure of Areva's decommissioned Shirley Basin tailings site has reached 0.0646 mg/l, more than twice EPA's 0.030 mg/l drinking water standard. Still, the actual value is less than half of the value of 0.15 mg/l expected by Areva at this location.
Uranium concentrations in groundwater near the tailings pile, that had stabilized at around 0.1 mg/l during the first decade after decommissioning, showed a more than tenfold sharp increase beginning in 2007 and now have reached values of up to 1.3 mg/l. Nevertheless, this is below the 4.45 mg/l Alternate Concentration Limit generously approved by NRC for this site in 2005 at Areva's request (see below).
Areva sees no connection between the sharp increase in uranium concentrations in groundwater and the observed increase in surface water: "This small change is not thought to be due to the tailings seepage."
> Download Semi-annual ground water monitoring report, Shirley Basin Mine, Pathfinder Mines Corp., Aug. 2011 external link (17.8MB PDF - ADAMS Acc. No. ML11252A529)

 

NRC approves further weakening of Pathfinder's Shirley Basin uranium mill tailings cover specifications

On July 1, 2004, NRC issued a license amendment approving relaxed requirements for the gradation of the clay to be used in the tailings cover. Now, only 70 percent, rather than 83 percent, must be passing a 200 size sieve (corresponding to a particle diameter of 75 µm or less). The radon exhalation from the covered pile, therefore, will be higher than anticipated, if the cover thickness remains unchanged.
However, in a license amendment issued on Aug. 1, 2003 (see below), the clay cover thickness already had been reduced to 6 inches [15.24 cm]. For the relaxed gradation requirement, NRC now calculates a radon flux of 19.2 pCi/m2s, only just below the regulatory limit of 20 pCi/m2s [0.74 Bq/m2s]. Given the uncertainties with such radon flux calculations, and, given that "the construction and 200-year minimum durability of a discrete 6-inch-thick clay layer is problematic", it is highly questionable that the cover will meet the radon flux limit in the long term. Nevertheless, NRC approved this further weakening of the cover specifications.

 

Pathfinder requests 2-year delay for completion of Shirley Basin uranium tailings cover

Federal Register: March 4, 2003 (Volume 68, Number 42) p. 10275-10276 (download full text external link)
"The U.S. Nuclear Regulatory Commission (NRC) has received, by letter dated December 26, 2002, as supplemented by an e-mail received February 3, 2003, a request from Pathfinder Mining Company to amend License Condition (LC) 50A(3) & 50B(1) of Source Material License SUA-442 for the Shirley Basin Site. The license amendment request proposes to modify LC 50A(3) to change the completion date for radon barrier placement to December 31, 2006, a delay of two years, and to modify LC 50B(1) to change the target completion date for the erosion protection placement to December 31, 2006, a delay of one year."

 

PMC requests amendment to the approved tailings reclamation plan in order to reduce cost

By letter dated Oct. 16, 2001, PMC requests an amendment to the approved tailings reclamation plan for its Shirley Basin uranium mill site. PMC believes that the current plan is not cost effective and that the the required volume of rock can significantly be reduced, while still meeting all NRC technical and safety criteria.
"The revised plan differs from the approved plan in two key ways. The revision involves a substantial increase in regrading in order to create relatively flat surfaces or benches that utilize rock-protected apron slopes to make the transition from upper benches to lower benches. The result is a reclamation surface covered primarily by vegetated topsoil instead of large expanses of rock.
The other significant change concerns the thickness of the radon barrier. When the approved plan was designed, the available information concerning the Ra-226 source term of the tailings was limited. [...] After completing the interim cover a tailings sampling program was initiated in order to obtain comprehensive data on the tailings source term. [...] The result of the analysis was a significantly lower source term than presented in the approved plan. Much of this reduction was due to the presence of substantial layers of interim cover that was treated for radon flux modeling purposes as the upper part of the source term. Consequently, the required barrier thickness to meet the 10 CFR 40 Appendix A radon flux criterium has dropped substantially." (emphasis added)

On Jan. 24, 2003, NRC staff issued an Draft Environmental Assessment proposing approval of PMC's amendment request.

On April 30, 2003, NRC announced a Finding of No Significant Impact and Availability of the Environmental Assessment Regarding the Proposed Changes to the Reclamation Plan:
Federal Register: May 9, 2003 (Volume 68, Number 90) p. 25070-25071 (view full text external link)

On Aug. 1, 2003, NRC changed the license accordingly.

 

NRC approves relaxed groundwater standards for Pathfinder's Shirley Basin uranium mill tailings

Notice in Federal Register Vol.65, No.92, p.30450 (May 11, 2000) (download full notice external link):
"SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) has received, by letter dated April 3, 2000, an application from Pathfinder Mines Corporation to establish Alternate Concentration Limits and, accordingly, amend Condition 47 of its Source Material License No. SUA-442 for the Shirley Basin Wyoming, uranium mill."

PMC requests a Point of Compliance ACL for uranium that is 64-fold and for thorium-230 19-fold the current site standard. The expected resulting concentrations at the "Point of Exposure" (defined by PMC) are for uranium 0.15 mg/l, and for thorium-230 0.3 pCi/l (0.011 Bq/l).
According to PMC, "the use of well water containing 0.15 mg U/l by the residents at this site is not expected to result in uranium burdens in the kidney that are associated with kidney damage." This uranium concentration, however, exceeds the proposed EPA standard of 20 µg/l 7-fold and the 1998 World Health Organization guideline of 2 µg/l 75-fold.

EPA std 40 CFR 192current POC site stdproposed POC ACLexpected POE conc. for proposed POC ACLEPA drinking water stdWHO drinking water guideline
uranium0.044 mg/l *0.07 mg/l4.40 - 4.45 mg/l0.15 mg/l0.02 mg/l ***0.002 mg/l
thorium-230(15 pCi/l) **0.3 pCi/l5.53 - 5.76 pCi/l0.3 pCi/l(15 pCi/l) **
* Combined U-238 and U-234: 30 pCi/l (equiv. 0.044 mg/l for equilibrium)
** Gross alpha-particle activity (excluding radon and uranium)
*** proposed
POC = Point of Compliance, POE = "Point of Exposure", ACL = Alternate Concentration Limit

Background documents are available through ADAMS external link.

On Dec. 24, 2002, NRC staff issued its draft environmental assessment of the request for Alternate Concentration Limits. From the conclusions:

"Based on its review, the NRC staff has concluded that the environmental impacts associated with the proposed action are not significant and, therefore, do not warrant denial of the license amendment request."

On July 31, 2005, NRC staff issued the final environmental assessment of the request for Alternate Concentration Limits. NRC staff proposes to approve the license amendment request with additional conditions, "because concerns exist regarding impacts to Spring Creek after CAP deactivation".

On August 25, 2005, NRC issued a Finding of No Significant Impact.
Federal Register: September 1, 2005 (Volume 70, Number 169) p. 52136-52137 (download full text external link)

 

PMC requests extension of reclamation completion date by two years

Notice in Federal Register Vol.64, No.241, p.70293-70294 (December 16, 1999) (download full notice external link):
"SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) has received, by letter dated October 29, 1999, an application from Pathfinder Mines Corporation (PMC) to amend License Condition (LC) 50 of its Source Material License No. SUA-442 for the Shirley Basin, Wyoming uranium mill site. The license amendment application proposes to modify LC 50 to change the completion date for three site-reclamation milestones. The new dates proposed by PMC would extend completion of placement of the interim cover over tailings pile, completion of placement of the final radon barrier, and completion of placement of the erosion protection cover by two years."

 

NRC approves reclamation plan

Notice in Federal Register Vol.63, No.225, p.64740-64741 (November 23, 1998) (download full notice external link):
"Pathfinder Mines Corporation, Final Finding of No Significant Impact, Notice of Opportunity for Hearing.

SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-442 to authorize Pathfinder Mines Corporation (PMC) to reclaim the Shirley Basin uranium mill site located in Carbon County, Wyoming. This license currently authorizes PMC to possess byproduct material in the form of uranium waste tailings generated by the licensee's milling operations at the site. An Environmental Assessment (EA) was performed by the NRC staff in support of its review of PMC's license amendment request, in accordance with the requirements of 10 CFR Part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) for the proposed licensing action of approval of a reclamation plan."


Petrotomics Co Shirley Basin South uranium mill site (Wyoming)

NRC Docket No. 40-6659 (PETROTOMICS)
NRC Source Material License No. SUA-551

> U.S. DOE Office of Legacy Management: Shirley Basin South site external link

Aerial View: Google Maps external link new window · MSRMaps external link new window

 

NRC not convinced that Shirley Basin South uranium mill tailings impoundment is not leaking

"NRC staff has reviewed DOE's report, and other information about the Shirley Basin South site as discussed below, as well as, DOE's proposed changes to the LTSP. Based on our review of this available information, the NRC staff has concluded that the current ground water monitoring data do not conclusively demonstrate whether or not the tailings impoundment is leaking.
Therefore, consistent with the following observations, the NRC staff has concluded that DOE's proposed revisions to the ground water monitoring program are not acceptable: [...] Therefore, in light of the foregoing, the NRC staff has concluded that the DOE should continue to monitor the ground water in accordance with the current ground water monitoring program." (NRC letter to DOE, March 25, 2014, emphasis added)

Elevated radium-226 concentrations in groundwater at Shirley Basin South uranium mill tailings disposal site not caused from seepage, DOE report

"A further review of Petrotomics' ACL application and groundwater modeling, combined with an evaluation of groundwater monitoring data collected by Petrotomics and DOE, indicate that elevated radium concentrations at the site represent localized ore mineralization. There is no evidence to suggest that the disposal cell is not functioning as designed, and the attenuation capacity of the formation is sufficient to prevent offsite plume migration of the legacy groundwater contamination. Furthermore, potential site-related contamination due to tailings seepage will not present any unacceptable risks at concentrations that are likely to be observed at the site boundary."
> Download Groundwater Evaluation and Recommended Monitoring for the Shirley Basin South, Wyoming, UMTRCA Title II, Disposal Site, August 2013 external link, LMS/SBS/S10313, U.S. Department of Energy - Legacy Management

Radium-226 exceeds alternate concentration limits in groundwater at Shirley Basin South uranium mill tailings disposal site

On Nov. 4, 2009, U.S. DOE notified NRC that a new monitoring well had a radium-226 concentration of 172 picocurries per liter (pCi/L) during the 2009 sampling event which exceeds the ACL of 91.3 pCi/L.
In an evaluation prepared in March 2011 and released on Oct. 6, 2011, DOE states: "At this time, there are insufficient data to definitively determine why radium-226 is elevated at well 110-DC." But, the available information "suggests that the elevated radium-226 concentrations at well 110-DC do not represent a contaminant plume migrating off site; rather, they more likely represent natural conditions as discussed below."
> Download Evaluation of Elevated Radium-226 and Radium-228 Concentrations at the Shirley Basin South, Wyoming, UMTRCA Title II Disposal Site external link, U.S. DOE Legacy Management, March 2011

Radium-228 exceeds alternate concentration limits in groundwater at Shirley Basin South uranium mill tailings disposal site

Shirley Basin South, Wyoming: the ground water alternate concentration limit for radium-228 continued to be exceeded at two monitor wells. The cause for this occurrence has not been determined. Regulatory notifications have been made and a recommended evaluative monitoring program is being conducted in accordance with the requirements of the Long-Term Surveillance Plan (LTSP). (2007 Annual Site Inspection and Monitoring Report for Uranium Mill Tailings Radiation Control Act Title II Disposal Sites, U.S. Department of Energy, Office of Legacy Management, November 2007)
> Download 2007 Annual Site Inspection and Monitoring Report external link
In an evaluation prepared in March 2011 and released on Oct. 6, 2011, DOE states: "Cell leakage does not appear to have caused the elevated concentrations of radium-228."
> Download Evaluation of Elevated Radium-226 and Radium-228 Concentrations at the Shirley Basin South, Wyoming, UMTRCA Title II Disposal Site external link, U.S. DOE Legacy Management, March 2011

NRC establishes U.S. Department of Energy as the long-term custodian of the Shirley Basin South uranium mill tailings site

Federal Register: June 29, 2005 (Volume 70, Number 124) p. 37448-37449 (download full text external link)

NRC terminates license for Petrotomics Shirley Basin tailings site

On June 8, 2005, NRC accepted the Long-term Surveillance Plan for the Petrotomics Shirley Basin tailings site and terminated the Source Material License No. SUA-551 for the site.

NRC approves relaxed groundwater standard for selenium at Petrotomics Shirley Basin tailings site

"By letter dated April 25, 2002, Petrotomics Company (Petrotomics) requested that License Condition (LC) 47B of the Shirley Basin site Source Materials License SUA-551 be amended to modify the groundwater protection standard for selenium at the designated point of compliance (POC) wells. Specifically, Petrotomics proposed to increase the standard for selenium from the current value of 0.023 mg/l to 0.12 mg/l at POC wells 5DC, 19DC, 5SC, and 51SC. In a telephone conference on August 21, 2002, the staff requested that Petrotomics perform additional selenium transport simulations to support the license amendment request and this additional information was provided in a letter dated September 12, 2002. The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of the Petrotomics amendment request and the staff’s detailed evaluation is documented in the enclosed Technical Evaluation Report (Enclosure 1).
Based on its review, the staff concludes that the Petrotomics request to amend LC 47B to modify the selenium groundwater protection standard is acceptable." (from NRC letter to Petrotomics, September 27, 2002, emphasis added)

Petrotomics Company "donates" uranium mining land to state

The Wyoming state Board of Land Commissioners has accepted a company's donation of 2,461 acres (996 ha) in the Shirley Basin. The land donated by Petrotomics Company, a subsidiary of ChevronTexaco Company, is about 30 miles north of Medicine Bow and 40 miles south of Casper. The land was once used for uranium mining but has not been mined since 1977. The Office of State Lands and Investments estimated the land is worth $250,000, or $100 per acre. The tract includes filled-in, open-pit uranium mines that were reclaimed by the Abandoned Mine Land Division of the Wyoming Department of Environmental Quality between 1986 and 1993, according to board documents.
Petrotomics is still transferring its mill site, encompassing 1,500 acres (607 ha) in the same area, to the U.S. Department of Energy for long-term study and monitoring. (Casper Star-Tribune August 10, 2002)

Tailings reclamation completed

On Nov. 30, 2001, Petrotomics submitted to NRC the Tailings Reclamation Construction Completion Report for the Shirley Basin tailings impoundment.
By letter dated Feb. 15, 2002, NRC accepted the report. The review of the report shall be completed by May 20, 2002.

Relaxed Groundwater Standards

Notice in Federal Register Vol.63, No.190, p.52777-52778 (October 1, 1998) (download full notice external link):
"Petrotomics Company, Shirley Basin, WY; Final Finding of No Significant Impact

SUMMARY: Notice is hereby given that the U.S. Nuclear Regulatory Commission (NRC) proposes to amend Petrotomics Company's (Petrotomics') Source Material License SUA-551, to allow alternate concentration limits (ACLs) for groundwater hazardous constituents at the Shirley Basin uranium mill site in Carbon County, Wyoming. An Environmental Assessment (EA) was performed by the NRC staff in accordance with the requirements of 10 CFR part 51. The conclusion of the EA is a Finding of No Significant Impact (FONSI) for this licensing action."

Petrotomics not able to comply with Wyoming groundwater standards at Shirley Basin uranium mill site

"Meeting Regarding Groundwater Cleanup at the Shirley Basin Uranium Mill Site

On August 13, 1998, staff from the Division of Waste Management met with representatives of the Petrotomics Company (Petrotomics), and the Wyoming Department of Environmental Quality (WDEQ) to discuss and resolve issues related to groundwater cleanup at Petrotomics' uranium mill site in Shirley Basin, Wyoming. The main issue is that Petrotomics would not be able to comply with the State of Wyoming groundwater standards, and unlike the Nuclear Regulatory Commission, the WDEQ standards have No risk-based provision such as those contained in 10 CFR Part 40, Appendix A, covering alternate concentration limits. Petrotomics discussed its approach in resolving the WDEQ identified technical issues as well as its plan to work with WDEQ in seeking flexibility in WDEQ's standards at the statutory level. Petrotomics is scheduled to submit its response to the technical issues to WDEQ by the middle of October 1998."

(NRC Weekly Information Report For the Week Ending August 21, 1998)


Umetco East Gas Hills site (Wyoming)

NRC Docket No. 40-0299 (UMETCO MINERALS CORP., RIVERTON, WY)
NRC Material License No. SUA-648

NRC Facility Info external link · Views (WMA) external link
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Attenuation of radium concentrations in groundwater not functioning as predicted at Umetco's former Gas Hills uranium mill site, NRC

"Figure 5 of the September 2013 report shows that 226+228Ra concentrations have increased in monitoring well (MW) 28 and decreased in MWI64 since about 2002. Umetco believes this indicates that the plume is moving across the site, as MW28 is hydrogeologically down gradient from MWI64. However, there does not appear to be any attenuation of constituent concentrations as described in the ACL [alternate concentration limit] application.
While the sampling data confirms that constituent concentrations remain well below the approved ACLs, the increasing 226+228Ra concentrations measured at monitoring well MW28 do not support the conclusions stated in the hazard assessment performed for approval of the ACL amendment request, i.e., that the constituent concentrations will be attenuated as the plume moves across the site towards the POE [Point of Exposure]. The apparent lack of attenuation taking place between MWI64 and MW28 may indicate that future constituent concentrations have the potential to be in excess of the background concentration of 69.5 pCi/l [2.57 Bq/l] at the POE in the WFR [Western Flow Regime]."
(NRC letter to Umetco Minerals Corp. March 11, 2014 external link, ADAMS Acc. No. ML14037A428)
> See also: UMETCO letter to NRC Sep. 18, 2013 external link (ADAMS Acc. No. ML13263A017)
> See also: UMETCO letter to NRC March 7, 2013 external link (ADAMS Acc. No. ML13070A088)

NRC issues Environmental Assessment on erosion enhancement design for Umetco's former Gas Hills uranium mill site

"The NRC staff concludes that Umetco's proposed actions to enhance the erosion protection design to correct the sub-grade erosion at its Gas Hill Reclamation Project will not significantly affect the quality of the human environment. Therefore, an environmental impact statement is not warranted for the proposed action. Pursuant to 10 CFR Part 51, the NRC staff has prepared this EA and determined that a Finding of No Significant Impact (FONSI) is appropriate for the proposed action to amend Umetco's license."
> Download Environmental Assessment for Umetco Minerals Corporation, Gas Hills reclamation project, above-grade tailings impoundment and A-9 repository erosion protection enhancement design report external link, U.S. NRC, Aug. 11, 2011
> Federal Register: August 19, 2011 (Volume 76, Number 161) p. 52022-52024 (download full text external link)
> Download Technical Evaluation Report, Aug. 22, 2011 external link

NRC issues Notice of Opportunity To Request a Hearing on erosion enhancement design for Umetco's former Gas Hills uranium mill site

Requests for a hearing must be filed by May 16, 2011.
Federal Register: March 16, 2011 (Volume 76, Number 51) p. 14437-14439 (download full text external link)
> Download Above Grade Tailings Impoundment and A-9 Repository Erosion Protection Enhancement Design Report external link, Dec. 20, 2010 (19MB PDF - ADAMS Acc. No. ML103640265)

Umetco requests dismissal of unfavourable groundwater monitoring results at former Gas Hills uranium mill site

By letter dated Sep. 22, 2009, Umetco notified the NRC that in two of four Point of Compliance (POC) wells, cadmium concentrations exceeded Maximum Contaminate Levels (MCL) established in 10 CFR 40, Appendix A. Umetco now claims "that the cadmium concentrations detected in two of the POC wells are erratically detected, not consistent with groundwater contamination and exclusion from the set of hazardous groundwater constituents at this site is appropriate".

NRC releases Draft Long-Term Surveillance Plan for the Gas Hills East (UMTRCA Title II) Disposal Site

> Download Draft Long-Term Surveillance Plan for the Gas Hills East (UMTRCA Title II) Disposal Site, Fremont and Natrona Counties, Wyoming, July 2009 external link (ADAMS Acc. No. ML092250176)

NRC approves relaxed Radium-226 standard for topsoil covers at Umetco Gas Hills uranium mill site

By letter dated Feb. 7, 2006, Umetco Minerals Corp. requests from NRC a license amendment to relax the Ra-226 standard for the 1-foot topsoil cover on the C-18 pit from 5 pCi/g (0.185 Bq/g) to 10 pCi/g (0.37 Bq/g). Umetco maintains that the Ra-226 background concentration in the area exceeds the 5 pCi/g criterion.
Umetco moreover requests to relax the Ra-226 standard for the cover of the GHP-2/Mill Area from 10 pCi/g (0.37 Bq/g) to 15 pCi/g (0.555 Bq/g), and to adjust the related gamma exposure limit from 30 µR/h to 40 µR/h.
On Nov. 22, 2006, NRC approved the requested license amendments.

U.S. NRC approves Umetco's request for relaxed groundwater standards for lead-210 at East Gas Hills uranium mill site

The requested license amendment was issued on March 24, 2006.

Federal Register: January 27, 2006 (Volume 71, Number 18) p. 4624 (download full text external link)
> Download NRC's Environmental Assessment, Jan. 20, 2006 external link (ADAMS)

By letter dated June 17, 2005, Umetco requested from NRC a license amendment to revise the Alternate Concentration Limit (ACL) for Lead-210 (Pb-210) for the Southwestern Flow Regime (SWFR) four-fold to 189 pCi/L (7 Bq/L), since monitoring of Point of Compliance (POC) Well GW7 indicates increased concentrations of Pb-210 exceeding the ACL of 46.7 pCi/L (1.73 Bq/L).

NRC approves relaxed groundwater standards for Gas Hills uranium mill site

Notice in Federal Register Vol. 67, No. 61, p. 15252-15254 (March 29, 2002) (download full notice external link):
"SUMMARY: The U. S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-648 to authorize the licensee, Umetco Minerals Corporation (Umetco) to apply Alternate Concentration Limits (ACL) to licensed constituents of ground water according to the submitted plan. An Environmental Assessment (EA) was performed by the NRC staff in support of its review of Umetco's license amendment request, in accordance with the requirements of 10 CFR Part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) for the proposed licensing action."

A request for a hearing must be filed within 30 days from March 29, 2002.

On May 11, 2001, Umetco had applied for Alternate Groundwater Concentration Limits at the Gas Hills uranium mill site.
> Download: Final Application for Alternate Concentration Limits For Gas Hills, Wyoming external link, Umetco Minerals Corporation, May 11, 2001 (ADAMS Acc. No. ML011490363)

Umetco Gas Hills site groundwater standards
ConstituentWestern Flow Regime
(Lower Wind River Aquifer)
Southwestern Flow Regime
(Upper Wind River Aquifer)
STDACLSTDACL
arsenic [mg/l]0.051.800.051.36
beryllium [mg/l]0.051.640.011.70
gross alpha [pCi/l]463,33817.86,223
lead-210 [pCi/l]5.035.44.646.7
nickel [mg/l]0.0613.00.049.34
radium-226+228 [pCi/l]31.525024.9353
selenium [mg/l]0.010.1610.010.53
thorium-230 [pCi/l]6.657.44.844.8
uranium-natural [mg/l]0.1311.90.2934.1
STD = Current Standard, ACL = Alternate Concentration Limit requested
1 pCi = 0.037 Bq

On January 25, 2002, NRC issued a draft Environmental Assessment for this application: "Based on its review, the NRC staff has concluded that the environmental impacts associated with the proposed action do not warrant denial of the license amendment. [...] The NRC staff has determined that the proper action is to issue a FONSI in the Federal Register."
> Download: Environmental Assessment of the application of alternate concentration limits to ground water at the Umetco Minerals Corporation, Gas Hills uranium mill site external link, March 24, 2002 (ADAMS Acc. No. ML020840234)

NRC approves disposal of offsite-material at Gas Hills uranium mill tailings site

On May 11, 2001, Umetco issued a license amendment request to dispose of International Mining Company (IMC) residual beneficiation materials at Umetco's Gas Hills site. The IMC material is located a few miles from the Gas Hills Wyoming site. The estimated disposal volume is approximately 2,000 cubic yards (1529 m3) with an estimated average Ra-226 concentration of approximately 220 pCi/g (8.14 Bq/g).
NRC approved the license amendment on August 10, 2001.

NRC approves decommissioning of contaminated land at Umetco East Gas Hills uranium mill site

Notice in Federal Register Vol.66, No.41, p.12962-12963 (March 1, 2001) (download full notice external link:
"SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-648 to authorize the licensee, Umetco Minerals Corporation (Umetco), to decommission the contaminated land associated with the operation of the uranium mill facility according to the Revised Soil Decommissioning Plan submitted September 15, 2000, as amended. The Umetco East Gas Hills site, is located in Natrona County, Wyoming, approximately 50 miles (80 kilometers) southeast of the town of Riverton, Wyoming. The mill operated from 1960 to 1979 and was dismantled in 1992. During operation, wind-blown tailings and tailings- solution from the Above-Grade Impoundment contaminated areas north of the Impoundment. A portion of the land contaminated with byproduct material was remediated (excavated) in 1993. Several changes and improvements have been proposed in the revised decommissioning plan.
An Environmental Assessment (EA) was performed by the NRC staff in support of its review of Umetco's license amendment request, in accordance with the requirements of 10 CFR part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) for the proposed licensing action."
A request for a hearing must be filed within 30 days from March 1, 2001.

The EA and other background documents are available through ADAMS external link.

NRC approves enhanced reclamation plan for A-9 in-pit tailings repository

Notice in Federal Register Vol.64, No.227, p.66512-66513 (Nov 26, 1999) (download full notice external link - watchout: wrong docket number shown in notice):
SUMMARY: The Umetco Minerals Corporation (Umetco) requested that the U.S. Nuclear Regulatory Commission (NRC) amend its NRC Source Material License SUA-648 to authorize reclamation of the A-9 Repository (disposal cell), located in Natrona County, Wyoming, according to the 1998 Enhanced Reclamation Plan, as amended. The Umetco East Gas Hills site is located approximately 50 miles (80 kilometers) southeast of the town of Riverton, Wyoming. The A-9 cell is a former surface uranium mine that was lined with clay and used for mill tailings disposal. Cover construction was begun under a previously approved reclamation design and several changes have been proposed in the enhanced plan. An Environmental Assessment (EA) was performed by the NRC staff in support of its review of Umetco's license amendment request, in accordance with the requirements of 10 CFR part 51. The conclusion of the EA is a Finding of No Significant Impact (FONSI) for the proposed licensing action.

NRC approves enhanced reclamation plan for above-grade tailings repository

Notice in Federal Register Vol.64, No.100, p.28220-28221 (May 25, 1999) (download full notice external link):
SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-648 to authorize the licensee, Umetco Minerals Corporation (Umetco), to reclaim the Above-Grade Impoundment (Impoundment), located in Natrona County, Wyoming, according to the 1997 Enhanced Reclamation Plan, as amended. The Umetco East Gas Hills site is located approximately 50 miles (80 kilometers) southeast of the town of Riverton, Wyoming. The Impoundment was constructed to a previously approved reclamation design, except for the top cover layer, and several changes have been proposed in the enhanced plan. An Environmental Assessment (EA) was performed by the NRC staff in support of its review of Umetco's license amendment request, in accordance with the requirements of 10 CFR Part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) for the proposed licensing action.

See also Notice in Federal Register Vol.63, No.231, p.66586 (Dec 2, 1998) (download full notice external link).

Approval of Cleanup for heap leach site

Notice in Federal Register Vol.63, No.87, p.25100-25101 (May 6, 1998) (download full notice external link):
"SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) proposes to amend NRC Source Material License SUA-648 to authorize the licensee, Umetco Minerals Corporation (Umetco), to reclaim the commercial heap leach area, located in Natrona County, Wyoming, according to the 1996 Reclamation Plan, as amended. This license currently authorizes Umetco to receive, acquire, possess, and transfer uranium at the Umetco East Gas Hills site, which is located approximately 50 miles (80 kilometers) southeast of the town of Riverton, Wyoming. An Environmental Assessment (EA) was performed by the NRC staff in support of its review of Umetco's license amendment request, in accordance with the requirements of 10 CFR Part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact (FONSI) for the proposed licensing action."

ANC Gas Hills uranium mill and tailings site, Wyoming

NRC Docket No. 40-4492 (AMERICAN NUCLEAR CORP., CASPER, WY)
NRC Material License No. SUA-667

NRC Facility Info external link
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Extension of site boundary envisaged as creative low-cost response to off-site groundwater plume at ANC Gas Hills uranium mill tailings site - in view of insufficient reclamation funds

"NRC and WDEQ recognize that, contrary to WDEQ's initial projections, there are insufficient funds remaining to finish reclamation of the site. [...] NRC and WDEQ have decided that the best use of the remaining reclamation funds would be the installation of new monitoring wells and surface water sampling stations to determine the extent of the groundwater plume flowing off-site and, if feasible, to purchase land to extend the site boundary beyond the plume."
(NRC letter to Wyoming Department of Environmental Quality, June 12, 2014, ADAMS Acc. No. ML14106A328)
(American Nuclear Corporation (ANC) forfeited its $3.2 million reclamation bond to Wyoming Department of Environmental Quality (WDEQ) in 1994, and WDEQ subsequently undertook reclamation activities at the site using these funds.)

Groundwater contaminant plume continues to spread off-site from ANC Gas Hills uranium mill tailings site

Wyoming DEQ's Summary of ANC Tailings Pond 1 Analysis dated May 5, 2014, finds that the groundwater contaminant plume at the ANC Gas Hills tailings site spread further off-site between 1989 and 2013. The current pump back system is considered to be inefficient and recommended for shut down.

NRC issues Notice of Violation to Wyoming DEQ on failure to meet monitoring requirements at ANC Gas Hills uranium mill tailings

During an inspection conducted on May 2-3, 2007, at the American Nuclear Corporation's (ANC) Gas Hills Project in Fremont County, Wyoming, the NRC found that the Wyoming Department of Environmental Quality had failed to perform the prescribed settlement and groundwater monitoring program. Consequently, the NRC issued a Notice of Violation on June 22, 2007.

Reclamation of ANC Gas Hills Tailings Pond No.1 delayed further

While the reclamation of the 80 acre (32 ha) Tailings Pond No. 2 at the ANC Gas Hills site was completed on October 30, 1997 - approx. 3 months before(!) NRC's approval of the related reclamation plan -, reclamation of 40 acre (16 ha) Tailings Pond No. 1 is further delayed. WDEQ still has not submitted yet the final design of the reclamation to the NRC. (Wyoming DEQ Annual Report for ANC Gas Hills Project, July 15, 2004)

Approval of Reclamation Plan

"On February 13, 1998, staff from the Division of Waste Management issued a letter approving the Final Reclamation Plan for Tailings Pond No. 2 at the American Nuclear Corporation (ANC) uranium mill and tailings site, Gas Hills, Wyoming. The plan was submitted by the Wyoming Department of Environmental Quality (WDEQ) external link, which is reclaiming the site under a Confirmatory Order issued by the Nuclear Regulatory Commission. ANC, the site owner and licensee, discontinued operation and went out of business in May 1994; the reclamation bond was forfeited to WDEQ, which accepted responsibility for site reclamation.

The ANC site reclamation plan was approved by NRC in 1984, and was one of the eight plans determined to be acceptable under Commission Paper SECY-95-155 on June 29, 1995.

WDEQ and its contractors worked with NRC staff to improve the ANC plan, and it is this improved plan which was approved February 13, 1998. The plan also included a preliminary reclamation plan for Pond No. 1; a final plan for Pond No. 1 will be submitted by WDEQ for NRC review and approval prior to reclamation of Pond No. 1."
(U.S. NRC Weekly Information Report for the week ending February 20, 1998)

> View American Nuclear Corp 2000 Annual Report (April 4, 2001) external link (EDGAR)


Day Loma heap leach site, Wyoming

Release for Unrestricted Use

(Nov.4, 1997) The Nuclear Regulatory Commission has released Western Nuclear, Inc.'s Day Loma uranium processing site in Wyoming for unrestricted use. The agency found that the site has been successfully remediated to meet federal requirements.
At the Day Loma site, Western Nuclear used the heap leach process to extract uranium from low-grade ore-bearing material that was transferred from its Split Rock uranium mill, about 20 miles away.

> View NRC press release No. 97-164 external link
> See also Notice in Federal Register Vol.62 p.55838-55840 external link (Oct. 28, 1997)


Bear Creek, Converse County, Wyoming

NRC Docket No. 40-8452 (BEAR CREEK URANIUM CO., CASPER, WY)
NRC Material License No. SUA-1310

NRC Facility Info external link
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NRC plans to drop requirement for groundwater monitoring at former Bear Creek uranium mill site in preparation of license transfer to DOE

In preparation of the termination of the license and transfer of the site to the U.S. Department of Energy (DOE), Anadarko Petroleum Corp. requested on Nov. 28, 2011, to move the previously designated Points of Exposure (POE) to wells located at the northern property boundary, and to drop the requirement for groundwater monitoring.
Comments must be filed by May 29, 2012.
A request for a hearing must be filed by June 25, 2012.
> Federal Register Volume 77, Number 81 (Thursday, April 26, 2012) p. 24993-24996 (download full text external link)
> Access Docket ID NRC-2012-0095 external link

On Feb. 27, 2013, NRC approved the request, facilitating the transfer of the site to the U.S. Department of Energy (DOE) for Long-Term Care and Surveillance. NRC staff nevertheless recommends that DOE continues a limited groundwater monitoring program "to verify the predictive accuracy of the revised ACL model over the entire recommended sampling period".
> Download Environmental Assessment external link, Feb. 2013
> Download Safety Evaluation Report external link, Feb. 2013
> Federal Register Volume 78, Number 84 (Wednesday, May 1, 2013) p. 25484-25486 (download full text external link)

Uranium concentrations in groundwater at Bear Creek tailings site exceed predicted values more then tenfold; NRC requests recalculation of alternate concentration limits

The Alternate Concentration Limit (ACL) application submitted on February 28, 1997, and approved by NRC on June 30, 1997, contained predictive modeling results for the maximum concentrations of nickel, radium, and uranium, at the Point of Compliance locations.
In well MW-14, however, uranium exceeded the predicted concentration of 45 pCi/l on several occasions and reached 520 pCi/l in 2008, more than 10 times the predicted value. This indicates that the assumptions used in the original 1997 predictive model to calculate the ACLs are not valid. NRC requests that a new risk-based ACL application be submitted incorporating the ground water data collected over the 13 years since the original ACL application. NRC requests the submittal of a new ACL application within 6 months.
> Download NRC letter to Andarko Petroleum Corp., Nov. 30, 2010 external link (ADAMS Acc. No. ML103280165)
In its reply dated Nov. 28, 2011, Anadarko Petroleum Corp. concluded: "The recalibrated ground water model predicts that the currently approved ACLs will not be exceeded and the risk assessment confirms there is no unacceptable risk to the public. Therefore, there is no need to change the ACLs." (ADAMS Acc. No. ML120470103 external link)

Institutional Controls at Bear Creek tailings fail miserably - even before they are relied on

The State of Wyoming has leased out the mineral estate at Bear Creek, although the State will be responsible for the long-term integrity of the reclaimed uranium mill tailings located on the site.
While DOE is the designated long-term custodian for the surface estate of the reclaimed Bear Creek uranium mill tailings site, the State of Wyoming will become the long-term custodian for the subsurface estate, obligated to ensure the long-term integrity of the tailings impoundment for 1000 years.
"... In this regard, the staff was particularly surprised to learn several months ago that the mineral estate at Bear Creek has already been leased. This discovery does not give the staff confidence that institutional controls such as, for example, restrictive covenants, will be sufficient to provide long-term protection of the disposal site, especially as memories fade in the future." (NRC letter to Wyoming Office of State Lands and Investments, Sep. 17, 2003)

Relaxed Groundwater Standards

Excerpt from Federal Register: June 27, 1997 (Volume 62, Number 124), Notices, Page 34718-34720; download full notice external link

"The U.S. Nuclear Regulatory Commission proposes to amend NRC Source Material License SUA-1310 for the licensee, Bear Creek Uranium Company, to allow alternate concentration limits for groundwater hazardous constituents at the Bear Creek uranium facility in Converse County, Wyoming. An Environmental Assessment was performed by the NRC staff in accordance with the requirements of 10 CFR Part 51. The conclusion of the Environmental Assessment is a Finding of No Significant Impact for the proposed licensing action."

> View background information on Uranium Mill Tailings Management - USA

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