Jump to main content.


Environmental Assessment and Finding of No Significant Impact for Site Protection Measures From Surface Water Flow, License Amendment No. 59; Rio Algom Mining, LLC, Ambrosia Lake, NM--SUA-1473

Note: EPA no longer updates this information, but it may be useful as a reference or resource.



PDF Version (3 pp, 59K, About PDF)


[Federal Register: August 8, 2008 (Volume 73, Number 154)]
[Notices]
[Page 46337-46339]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08au08-98]

=======================================================================
-----------------------------------------------------------------------

NUCLEAR REGULATORY COMMISSION

[Docket No.: 40-8905]

Environmental Assessment and Finding of No Significant Impact for
Site Protection Measures From Surface Water Flow, License Amendment No.
59; Rio Algom Mining, LLC, Ambrosia Lake, NM--SUA-1473

AGENCY: U.S. Nuclear Regulatory Commission.

ACTION: Issuance of Environmental Assessment.

-----------------------------------------------------------------------

FOR FURTHER INFORMATION CONTACT: Thomas McLaughlin, Project Manager,
Materials Decommissioning Branch, Division of Waste Management and
Environmental Protection, Office of Federal and State Materials and
Environmental Management Programs, U.S. Nuclear Regulatory Commission,
Washington, DC, 20555. Telephone: (301) 415-5869; fax number: (301)
415-5369; e-mail: tgm@nrc.gov.

SUPPLEMENTARY INFORMATION:

I. Introduction

    By letter dated October 24, 2007, as supplemented on January 31,
2008, and March 21, 2008, Rio Algom Mining, LLC, (Rio Algom, or the
Licensee) submitted an application to the U.S. Nuclear Regulatory
Commission (NRC), requesting an amendment to Source Materials License
SUA-1473 for the Ambrosia Lake Mill Facility, in Ambrosia Lake, New
Mexico. Rio Algom seeks the approval of its proposed site erosion
protection measures designed to prevent surface water flow from
damaging its uranium mill tailings site. The NRC prepared an
Environmental Assessment (EA) for this proposed action in accordance
with the requirements of 10 CFR Part 51. Based on the EA, the NRC
concluded that a Finding of No Significant Impact (FONSI) is
appropriate with respect to the proposed action. The amendment would be
issued following the publication of this FONSI and EA in the Federal
Register.
    The Licensee has indicated that the proposed site erosion
protection measures from surface water flow are the final component of
the overall site reclamation plan. The Licensee previously has
addressed, and NRC has approved, the remaining site-wide reclamation
plan elements through separate licensing actions, including the
original reclamation plan for Tailings Cells 1, 2, and 3 (approved in
September 1990), mill demolition, relocation of lined evaporation pond
sediments, soil decommissioning plan, and groundwater remediation. The
expansion of Tailings Cell 2 was approved by License Amendment No. 58.
The current licensing action is to protect the Tailing Cells from
erosion from surface water by constructing a channel to divert water
flow around them.

II. Environmental Assessment

1.0 Background

    The Ambrosia Lake site is in the Ambrosia Lake Mining District of
New Mexico, 25 miles north of Grants, New Mexico. Rio Algom began
processing ore in 1958, and processed approximately 33 million tons of
ore through 1985. The site continued to be an active uranium production
facility through December 2002. Site reclamation activities commenced
in 1989 with some work on the top surface of the largest tailings cell.
There are three tailings/waste cells situated adjacent to each other at
the Rio Algom site: The large Tailings Cell 1, Tailings Cell 2 to the
west of Cell 1, and a small Cell 3 east of Cell 1 that was used to
dispose of contaminated windblown material. Reclamation of Cell 1 is
complete, and cover construction of Cells 2 and 3 is still ongoing and
almost complete. Reclamation activities have at times included unlined
evaporation pond residue excavation and disposal, contaminated
windblown soil cleanup, tailings impoundment reclamation, surface water
erosion protection feature construction, and mill building demolition.
    In meetings and discussions with the Licensee in 2006 and 2007, the
NRC staff was informed that Rio Algom intended to leave remaining
contaminants under Ponds 4, 5, and 6 in place in the Arroyo del Puerto
floodplain. Ponds 4, 5, and 6 were unlined and uranium, radium-226, and
thorium-230, have been found to extend to 10 feet deep in some areas.
The top 4 to 5 feet of contaminated soil in these Ponds have been
removed and the material placed in Tailings Cell 3, then the footprint
was covered with 1 to 2 feet of clean soil. The staff expressed
concerns that the remaining contaminates under the Ponds needed to be
protected from erosion due to

[[Page 46338]]

periodic flooding that occurs in the Arroyo del Puerto. These Ponds
extend over an area of about 50 acres and must be stabilized and
protected from erosion. They are located inside the exterior diversion
berm, but need to be protected from the effects of direct precipitation
and the resulting overland runoff. RAMC proposes to provide a 3-inch
thick layer of rock to protect the top slope from erosion. Rio Algom's
decision to leave this material in place has resulted in significant
changes to the overall design of the Arroyo del Puerto channel. Major
revisions included construction of a very large diversion channel and
significant additions of riprap to protect against erosion and lateral
migration of the re-aligned channel.
    The re-design and protection of the Arroyo del Puerto channel is
the last phase of the Ambrosia Lake facility reclamation. The NRC staff
recently approved License Amendment 58 which finalized the capping of
the remaining mill tailing waste in Tailings Cell 2. An extensive EA
was prepared for this licensing action (See ADAMS ML072670278 dated 10/
31/2007) which included the discussion of land use, geology, surface
and ground water, ecology (flora and fauna), climate, socioeconomic
impact, historical and cultural resources, public and occupational
health, and transportation. The scope of the current EA, which
evaluates the construction of a channel to divert water flow away from
the three Tailings Cells and Ponds 4, 5, and 6 to protect them from
erosion, is limited to the construction impacts, as all other impacts
were previously evaluated in the Tailings Cell 2 expansion EA completed
in October 2007.

2.0 The Proposed Action

    The proposed action is to amend NRC Source Materials License SUA-
1473 to approve the construction of a channel to divert water flow away
from the three Tailings Cells and Ponds 4, 5, and 6 to protect them
from erosion caused by surface water flow. To comply with Criterion 6
of 10 CFR 40, Appendix A (which requires stability of mill Tailings
Cells for 1000 years to the extent reasonably achievable and in any
case for 200 years), the Licensee proposes to significantly modify the
alignment of the original channel by constructing a new channel and
berm on the east side of Ponds 4, 5, and 6. The overall design includes
construction of: (1) A new exterior diversion channel and berm; (2) a
new interior drainage channel; (3) modified riprap protection for mill
Tailing Cell 3; and (4) additional riprap protection for Ponds 4, 5,
and 6. Each of these design features requires rock riprap erosion
protection to assure long-term stability.

3.0 Need for the Proposed Action

    The need for the proposed action is to address NRC concerns about
the potential periodic flood conditions of the original channel due to
heavy rains, and the long-term stability for the three mill Tailings
Cells, and for protection of Ponds 4, 5, and 6. Periodic heavy rains
have the potential to wash away the covered uranium mill waste in the
three Tailings Cells and under Ponds 4, 5 and 6, and carry the uranium
waste outside the property boundary of the Licensee. The purpose of the
re-designed channel is to divert any flood water away from the three
Tailings Cells and Ponds 4, 5 and 6. This EA fulfills the NRC's
responsibilities under the Atomic Energy Act to make a decision on a
proposed license amendment in a manner that ensures protection of the
environment.

4.0 The Environmental Impacts of the Proposed Action

    The potential direct impacts of the proposed action are short-term
impacts from construction. Long-term and indirect impacts are
considered as part of the previously cited analysis. The direct impacts
from construction activities primarily would be dust generation due to
excavating material to form the channel, noise generated by
construction equipment, and water surface runoff. Fugitive dust from
heavy equipment operation would be mitigated through the use of dust
suppression methods on haul roads. Noise suppression devices will be
worn by workers when necessary. The Licensee's implementation of its
National Pollutant Discharge Elimination System (NPDES) permits, its
Storm Water Pollution Prevention Plan for the site, its site Health,
Safety and Environment Management System, and NRC license requirements
would provide adequate assurances to avoid adverse impacts to the
environment. Additional ambient air monitoring stations have been
installed to collect data from the dust produced during the work
activity to demonstrate that control measures would be implemented and
effective. These high volume air sampling stations measure the amount
of natural Uranium, Th-230, Ra-226, and Pb-210, and the concentrations
are compared to the limits described in License Condition No. 10.
Potential impacts at the tailings cell area would be small since the
area is already disturbed from site reclamation activities and the
associated impacts were previously evaluated.
    The staff evaluated the potential impacts associated with the
Licensee's proposed construction of a channel to divert water from the
three mill Tailings Cells and Ponds 4, 5, and 6. The staff finds that
the mill tailings waste contained in the three Tailings Cells, and the
contaminants in Ponds 4, 5, and 6 would be adequately protected from
the effects of erosion that can be caused by the periodic flooding of
the Arroyo del Puerto.
    The Licensee prepared a technical memorandum to respond to New
Mexico Department of Environmental Quality (NMDEQ) comments about the
disruption or elimination of monitoring wells during the construction
of the channel. The technical memorandum stated that no monitoring
wells would be abandoned or replaced as the result of the construction
of the new diversion channel. However, there are five wells within the
area of construction that would have changes in their final surface
elevations from construction activities.
    The NMDEQ and NRC staff also had concerns about the potential for
surface water infiltration. The Licensee prepared a second technical
memorandum to respond to the question of surface water infiltration and
the potential for ground water recharge to the alluvial system beneath
the channel from surface water flow. After reviewing the Licensee's
response in their second technical memorandum, NRC staff concluded that
Rio Algom adequately explained that the infiltration potential within
the Ambrosia Lake Mill site would be small. The following are the most
significant points stated by the Licensee that supports its conclusion
that infiltration (recharge to the water table) is small:
     The drainage area for the Interior Drainage Channel is
limited (less than a square mile--440 acres), thus, the surface runoff
amounts would be small.
     The soils in the vicinity of the Arroyo del Puerto at the
Ambrosia Mill site are greater than 30 feet deep, and are composed of
fine sandy silt to silty fine sand. Because of their fine texture and
low permeability, they would retain more soil moisture than coarser
textured soils. As a result, the evapotranspiration process would
remove much of the soil moisture before it reaches the water table.

The evaporation rate for this site (54 inches/year) is greater (more
than 6 times) than the annual precipitation (8.83 inches/year).

[[Page 46339]]

5.0 Alternatives to the Proposed Action

    The staff considered denial of Rio Algom's request (i.e., the no
action alternative) as the only reasonable alternative to the proposed
action. Denial of the Licensee's request would result in no protection
from the spreading of contaminants from the capped mill tailing cells
or the contaminants in Ponds 4, 5, and 6 from potential flooding in the
Arroyo del Puerto floodplain.

6.0 Agencies and Persons Consulted

    This EA was prepared by the NRC staff, and coordinated with the
NMDEQ. NRC staff provided a draft of its EA to NMDEQ for review. NMDEQ
had multiple comments on the Draft EA and the overall design of the
proposed channel. Several discussions were held with the staff of NMDEQ
and their comments were incorporated into the Draft EA and the
technical evaluation report which would accompany the license
amendment.
    A cultural resource survey was conducted on the archeological site
discovered during the site inspection, and concluded that no cultural
resource sites are present, and that the area is ineligible for
inclusion in the National Register. Rio Algom sent a letter to the
State of New Mexico Department of Cultural Affairs (NMDCA), Historic
Preservation Division (HPD), notifying them of the archeological site
and the redesign of the channel and 1000-year (flood control) berm to
avoid disturbing the area. The NRC staff contacted the NMDCA, HPD,
which stated that the site was eligible for inclusion in the National
Register, but concurred with the proposed realignment of the channel
project to avoid the archeological site, and stated that, as long as
the site is avoided, the project would not affect historic properties.
The NRC staff has determined that no further consultation would be
required under Section 106 of the National Historic Preservation Act.
    The NRC staff has determined that the proposed action would not
affect any federally- or state-listed (threatened and endangered)
species or their critical habitat. Therefore, no further consultation
would be required under Section 7 of the Endangered Species Act. The
NRC staff advised the Licensee to contact the U.S. Army Corps of
Engineers (USACE) to inquire if this project would require a Section
404 (Clean Water Act) permit. The NRC staff contacted the USACE about
the Section 404 permit and they requested that NRC send the technical
memoranda from the licensee, the concurrence from NMDCA, HPD on the
proposed channel design, and the Federal Register Notice (FRN) with the
EA (See ADAMS ML081890038). The NRC staff sent the technical
memorandums and concurrence from NMDCA, HPD to the USACE and will send
the FRN when it is finalized. The USACE will then decide if a Section
404 permit is required.

7.0 Conclusion

    The NRC staff prepared this EA in support of the proposed action.
Based on the analysis contained in this EA, the staff concluded that
there are no environmental impacts from the proposed action, and that
the preparation of an Environmental Impact Statement is not warranted.
Accordingly, the NRC determined that a Finding of No Significant Impact
is appropriate.

III. Further Information

    For further details with respect to the proposed action, see the
Licensee's letter and report dated October 24, 2007 (See ADAMS
ML073060379, ML073060380, ML073060381, ML073060382, and ML073060383), a
report from the Licensee dated January 31, 2008 (See ADAMS ML080350250,
ML080350251, ML080350252, ML080350254, and ML080350259), a report from
the Licensee dated March 21, 2008 (See ADAMS ML080990026, ML080990027,
ML080990034, and ML080990035), a technical memorandum from the Licensee
dated May 8, 2008 (See ADAMS ML081280101), and a revised technical
memorandum from the Licensee dated May 21, 2008 (See ADAMS
ML081490526), all of which are available for public inspection, and can
be copied for a fee, at the U.S. Nuclear Regulatory Commission's Public
Document Room (PDR), located at One White Flint North, 11555 Rockville
Pike (first floor), Rockville, Maryland, 20852. The NRC maintains an
Agency-wide Documents Access and Management System (ADAMS), which
provides text and image files of NRC's public documents. These
documents may be accessed through the NRC's Public Electronic Reading
Room on the internet at http://www.nrc.gov.
    Persons who do not have access to ADAMS or who have problems in
accessing the documents located in ADAMS may contact the PDR reference
staff at 1-800-397-4209, 301-415-4737 or by e-mail at pdr@nrc.gov.

    Dated at Rockville, Maryland, this 1st day of August, 2008.

    For The Nuclear Regulatory Commission.
Rebecca Tadesse,
Acting Deputy Director, Decommissioning and Uranium Recovery, Licensing
Directorate, Division of Waste Management, and Environmental
Protection, Office of Federal and State Materials and Environmental
Management Programs.
[FR Doc. E8-18289 Filed 8-7-08; 8:45 am]

BILLING CODE 7590-01-P

 
 


Local Navigation


Jump to main content.