[Federal Register Volume 65, Number 39 (Monday, February 28, 2000)]
[Notices]
[Pages 10567-10570]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-4583]


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NUCLEAR REGULATORY COMMISSION

[License 02-08779-01--Docket 30-03583]


Department of the Interior, Geological Survey, WRD, Arizona 
District: Termination of Material License; Finding of No Significant 
Impact and Notice of Opportunity for a Hearing

    The U.S. Nuclear Regulatory Commission (NRC) is considering 
terminating Material License 02-08779-01. This would allow the United 
States Geological Survey (USGS) to discontinue licensed maintenance 
activities for a radioactive 2.5 Ci \241\Americium--Beryllium (Am-Be) 
well logging source that it was unable to retrieve from an artesian 
well (#10) in the San Bernardino National Wildlife Refuge (SBNWR), 
Arizona. As a condition for the license termination, USGS would need to 
satisfactorily implement abandonment procedures for the well logging 
source as described in 10 CFR 39.15(a)(5).

Summary of the Environmental Assessment

Identification of the Proposed Action

    The proposed action would terminate USGS's Material License 02-
08779-01. With this termination, the USGS would be able to discontinue 
licensed maintenance activities for a 2.5 Ci \241\Am-Be well logging 
source that was determined to be irretrievable from well #10 in the San 
Bernardino National Wildlife Refuge.

The Need for the Proposed Action

    The proposed action would determine if the license should be 
terminated. USGS previously took action to fulfill its obligation under 
NRC regulations to implement abandonment as described in 10 CFR 
39.15(a)(5) by attempting to seal the source in place with cement. 
However, follow-up visual examination of the well with a downhole 
camera produced no evidence that the cement plug actually formed. The 
radioactive source has been underwater in the well for almost 12 years 
and USGS has conducted periodic sampling. During that time, the 
intermittent monitoring by USGS has not conclusively indicated whether 
or not water from the well has been contaminated by the source.
    USGS has requested permission from the NRC to cease its monitoring 
activities and end USGS responsibilities related to the Am-Be source. 
Because of uncertainties related to the condition of the stainless 
steel source container, the effectiveness of a cement plug already 
installed, the impact additional attempts to recover the source may 
impose, and concerns about the potential for future contamination, NRC 
decided to prepare an environmental assessment (EA) to analyze three 
alternatives for final disposition of the Am-Be source: (1) Abandonment 
in place; (2) source retrieval; and (3) the no-action alternative.

[[Page 10568]]

Alternatives

    Two of the three alternatives, abandonment in place and source 
retrieval, could ultimately result in license termination. The 
recommended alternative is abandonment of the source in place 
subsequent to compliance with NRC requirements for abandonment. Another 
potential alternative for final disposition of the source is 
undertaking an additional attempt at source retrieval by overdrilling 
the borehole and overcoring the cement plug. Denial of the license 
termination, the no-action alternative, is also available to NRC, but 
could require that monitoring continue indefinitely.

Background

    The SBNWR is located approximately 30 km (19 miles) east of Douglas 
in southeastern Arizona immediately north of the Mexican border. The 
nearest city in Mexico is Agua Prieta, approximately 35 km (21 miles) 
to the southeast. The 930-ha (2,300-acre) SBNWR lies near the center of 
the San Bernardino Valley, a surface water drainage basin that 
straddles the U.S.-Mexican border.
    In 1986, the U.S. Fish and Wildlife Service (FWS) requested that 
USGS log an artesian well (Well 10) that feeds Twin Pond within the 
SBNWR to assess the water production capacity of the well. Water from 
the well initially flows into a pond containing three federally 
threatened or endangered fish species and water from this pond, in 
turn, feeds an adjacent pond/wetland containing an endangered plant 
species.
    The USGS used a radioactive sealed source to conduct well logging 
for the purpose of quantifying the water production capacity of the 
artesian well. The source is composed of \241\Am (originally 2.53 Ci) 
and Be compressed into a cylindrical pellet, within a double-walled 
stainless steel container. The radioactive material in the source, 
\241\Am (half-life of 432 years), emits alpha radiation which dislodges 
neutrons from Be. The Am-Be source is part of a larger neutron 
emission/detection tool commonly used in well logging. On July 15, 
1986, the Am-Be neutron well-logging source was ``lost'' by USGS in 
Well 10. The Am-Be tool was torn from the logging cable as it was being 
returned to the surface during a logging run and the logging probe 
containing the source fell back down the well.
    Three series of attempts were made to recover the source between 
July 15, 1986, and October 21, 1987. During these recovery attempts, 
the logging probe was damaged and the source was separated from the 
body of the well logging tool. USGS declared the source irretrievable 
on October 20, 1987. After this decision was reached, and in accordance 
with 10 CFR 39.15(a)(5), a 0.76 m\3\ (1 yd\3\) cement plug was emplaced 
around and above the source (that was presumed to be at the bottom of 
the well) and an inverted tricone drill bit with a 5-ft drill pipe 
subassembly was placed in the well at the top of the cement to prevent 
intrusion into the source.
    On March 30, 1988, USGS returned to the site to inspect the well. 
Video logging of the well produced no evidence of the cement plug 
previously installed by USGS, and found the bottom of the well at a 
depth of 176 m (577 ft)--some 14 m (46 ft) deeper than the well depth 
sounded after emplacement of the cement and drill bit in 1987. The 
unexpected depth at which the well bottom was located after source 
abandonment and the lack of cement at the depth where it was expected 
to be encountered might be explained in two ways: (1) the fact that the 
original total drilled depth of the well is unknown, and (2) the 
possibility that drill cuttings or collapsed borewall material may have 
formed a bridge in the well at the 178 m (583 ft) depth.
    The USGS has sampled the Well 10 water for \241\Am. Three samples 
collected in 1989 and 1990 indicated only traces of \241\Am in the well 
water, while the last four samples taken in 1990 did not show the 
presence of \241\Am. Based on the results of sampling for \241\Am in 
the well, USGS believes that continued monitoring is unwarranted.

Environmental Impacts

    Because of the limited scope of activities, the EA focuses on 
geology/hydrology and impacts to ecological resources, and human health 
which might result from three alternatives for final disposition of the 
Am--Be source. The proposed alternatives would not (1) cause 
appreciable changes in employment at the site, (2) affect previously 
undisturbed areas, or (3) expand the developed area of the site. For 
these reasons, no significant impacts on socioeconomic, historic or 
archaeological resources would result from the proposed alternatives.

The Recommended Alternative: Abandonment in Place

    The recommended alternative would abandon the radioactive source in 
place consistent with the requirements of 10 CFR Part 39.15. This 
regulation requires sealing the source in place with a cement plug, 
installing a mechanical device to prevent inadvertent intrusion, and 
posting a permanent sign with detailed descriptions of the source and 
borehole conditions.
    The installation of a cement plug in the bottom portion of the well 
would provide for the positive sealing of the well below a depth of 152 
m (500 ft) to isolate the source from the upper part of the well. The 
plug would prevent future mixing of \241\Am in water at the bottom of 
the well and would further reduce the likelihood of contaminant 
migration up the well column. Pressure grouting of the bottom of the 
well using low pressure pumps would force cement down into the low 
permeability region of the well, encapsulating the lost Am'Be source, 
the drilling subassembly and bit (intrusion preventer) previously 
placed in the well, and filling the wellbore to the desired level. 
Emplacement of this plug would effectively seal the logging source and 
drill bit assembly in place permanently and seal any \241\Am 
contamination which might leak from the source within the inactive 
groundwater flow zone.
    This action would eliminate the possibility of potential mixing of 
contaminated water at the well bottom with the discharging artesian 
flow. With completion of the cementing of the well base, any 
contaminant release scenario would be by diffusion of the contaminant 
upward through approximately 30 m (100 ft) of cement grout or through 
the native silts and clays of the geologic formation surrounding the 
well. The combination of very low groundwater flow in this region and 
geochemical retardation processes would contain the americium from the 
source beneath the useable aquifer. Therefore, under this alternative 
no adverse impact would be expected to either the water quality of Well 
10 or other wells in the area. After plugging the basal portion of the 
well, continued discharge of the artesian flow to the ponds and 
wetlands could continue.
    Under this alternative, near-term ecological impacts would be minor 
and temporary, involving only minimal disturbance to the well site. 
Based on a Department of Energy (DOE) methodology for evaluating 
radiation effects on aquatic biota, no effects would be expected. 
Therefore, there is little potential for effects on any of the species 
of fish present in Twin Pond. As the \241\Am in solution sorbs to 
sediments, the concentration in water would become markedly less, and 
dose to fish would decrease even more. At such low levels, effects to 
other pond biota less sensitive than teleost fish would not be 
expected.

[[Page 10569]]

    Because well 10 is located approximately 30-35 km (19-21 miles) 
from the nearest population centers, Douglas, Arizona, and Agua Prieta, 
Mexico, respectively, the EA finds there is little potential for an 
individual to have direct contact with Well 10 water.
    Another route the EA examined for exposure to Well 10 contamination 
would be through the use of water from wells drilled into the same 
aquifer for drinking or irrigation. Because the geology and hydrology 
of the site and nearby region are complex and not thoroughly 
understood, several perspectives on human risk are presented to provide 
a picture of the potential risk.
    As a bounding analysis, the EA evaluates the possibility that if, 
after many years, a contaminated plume of water could reach a 
hypothetical agricultural well about 1,000 m (3,300 ft) from the 
original contaminated source, the approximate annual dose would be less 
than 3 Sv/yr (0.3 mrem/yr), well below any Environmental 
Protection Agency and NRC regulatory limit of concern. Because home use 
pumping rates would not provide the ``pressure relief'' considered with 
the agricultural well, it is unlikely that water from the deep, slowly 
moving water would be taken up in the home well. Therefore, essentially 
no radiation dose would be received for the case of a home well.

Source Retrieval Alternative

    Under this alternative, Well 10 would be re-drilled to a larger 
diameter and all liquids and solids removed would be contained and 
disposed of off-site. If the source has already been breached, the 
drill cuttings, particularly those from the deeper part of the well, 
would be expected to be contaminated with Am released from the source. 
If the source has not been breached, the potential exists that it could 
be breached during the retrieval process resulting in \241\Am being 
dissolved in the drilling fluid and the water.
    An accidental breach of the source container while conducting this 
alternative would be completely or at least partially controlled by the 
containment procedures that would be implemented. However, the 
potential for an accidental release from a breached source is a 
negative factor for this alternative. This could result in occupational 
doses and the potential for this area to be restricted from public 
access.
    As a bounding scenario for this assessment, the EA has assumed that 
the entire contents of the source are lost directly into Twin Pond. 
Using a DOE methodology for evaluating radiation effects on aquatic 
biota, adverse effects could be expected.

No-action Alternative

    Under the no-action alternative, the potential would remain for 
discharge of \241\Am contaminated water or particulate material from 
Well 10 into the adjacent ponds and wetlands. In addition, in the 
future, someone could inadvertently drill into the source in an effort 
to redevelop the well. Estimation of the likely concentrations that 
would be expected to result from this discharge suggests that the 
discharge would occur at low concentration over a long period of time 
since the \241\Am is expected to adsorb to soil and other particulate 
materials in the ground or in the well. Under this condition, no acute 
water quality, ecological, and human health effects would be expected. 
However, because the Am-Be source would not be sealed in the lower part 
of the well, continued monitoring would be necessary to ensure that 
unexpected contaminant concentrations do not occur in water or pond 
sediment.

Agencies and Persons Consulted

    The FWS was consulted on the proposed action with respect to 
Section 7 of the Endangered Species Act of 1973. The State Historic 
Preservation Officer for the State of Arizona was consulted with 
respect to Section 106 of the National Historic Preservation Act.

Conclusion

    The assessment of the recommended alternative, abandonment in 
place, indicates it would not result in adverse water quality or human 
health impacts and would produce only temporary and minor ecological 
impacts associated with emplacement of the cement plug. The potential 
exists that the source could be breached during the alternative of 
attempting source retrieval by overdrilling the borehole resulting 
in\241\ Am being dissolved in the drilling fluid and the water and, 
therefore, additional effects could be expected. While not terminating 
the license would be unlikely to produce significant adverse impacts, 
it would require continued monitoring to ensure that unexpected 
contaminant concentrations do not occur in water or pond sediment.
    The NRC staff concludes that provided USGS satisfactorily 
implements abandonment procedures for the well logging source as 
described in 10 CFR 39.15(c), the environmental impacts associated with 
the proposed license termination allowing the USGS to discontinue 
licensed maintenance activities for the 2.5 Ci;\241\ Am-Be well logging 
source are expected to be insignificant.

Finding of No Significant Impact

    The Commission has prepared an EA related to the termination of 
Material License 02-08779-01. Based on the EA, as previously 
summarized, the Commission has concluded that environmental impacts 
that would be created by the proposed action would not have a 
significant effect on the quality of the human environment and do not 
warrant the preparation of an Environmental Impact Statement. 
Accordingly, it has been determined that a Finding of No Significant 
Impact is appropriate.
    Copies of the EA, NUREG/CR-6648, may be purchased from the 
Superintendent of Documents, U.S. Government Printing Office, P.O. Box 
37082, Washington, DC 20402-9328. Copies are also available from the 
National Technical Information Service, 5285 Port Royal Road, 
Springfield, VA 22161. A copy is available for inspection and copying 
for a fee in the NRC Public Document Room, 2120 L Street, NW. (Lower 
Level), Washington, DC 20555-0001. The document is also accessible 
electronically through the ADAMS Public Legacy Library component on the 
NRC website, HTTP://www.nrc.gov, the ``Public Electronic Reading 
Room.''

Opportunity for a Hearing

    Any person whose interest may be affected by the issuance of this 
license termination may file a request for a hearing. Any request for 
hearing must be filed with the Office of the Secretary, U.S. Nuclear 
Regulatory Commission, Washington, DC 20555, within 30 days of the 
publication of this notice in the Federal Register; be served on the 
NRC staff (Executive Director for Operations, One White Flint North, 
11555 Rockville Pike, Rockville, Maryland 20852), and on the licensee 
(Department of the Interior, Geological Survey, WRD, Arizona District, 
520 N. Park Ave., Suite 221, Tucson, AZ 85719); and must comply with 
the requirements for requesting a hearing set forth in the Commission's 
regulations, 10 CFR Part 2, Subpart L, ``Information Hearing Procedures 
for Adjudications in Materials Licensing Proceedings.''
    These requirements, which the request must address in detail, are:
    1. The interest of the requestor in the proceeding;
    2. How that interest may be affected by the results of the 
proceeding (including the reasons why the requestor should be permitted 
a hearing);

[[Page 10570]]

    3. The requestor's areas of concern about the licensing activity 
that is the subject matter of the proceeding; and
    4. The circumstances establishing that the request for hearing is 
timely--that is, filed within 30 days of the date of this notice.
    In addressing how the requestor's interest may be affected by the 
proceeding, the request should describe the nature of the requestor's 
right under the Atomic Energy Act of 1954, as amended, to be made a 
party to the proceeding; the nature and extent of the requestor's 
property, financial, or other (i.e., health, safety) interest in the 
proceeding; and the possible effect of any order that may be entered in 
the proceeding upon the requestor's interest.

    Dated at Rockville, Maryland, this 14th day of February, 2000, 
For the Nuclear Regulatory Commission.
John W. N. Hickey,
Chief, Material Safety and Inspection Branch, Division of Industrial 
and Medical Nuclear Safety, Office of Nuclear Material Safety and 
Safeguards.
[FR Doc. 00-4583 Filed 2-25-00; 8:45 am]
BILLING CODE 7590-01-P