[Federal Register Volume 75, Number 179 (Thursday, September 16, 2010)]
[Pages 56597-56601]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-23114]



[Docket No. 50-156; NRC-2010-0203]

University of Wisconsin; University of Wisconsin Nuclear Reactor 
Environmental Assessment and Finding of No Significant Impact

    The U.S. Nuclear Regulatory Commission (NRC or the Commission) is 
considering issuance of a renewed Facility Operating License No. R-74, 
to be held by the University of Wisconsin (the licensee), which would 
authorize continued operation of the University of Wisconsin Nuclear 
Reactor (UWNR), located in Madison, Dane County, Wisconsin. Therefore, 
as required by Title 10 of the Code of Federal Regulations (10 CFR) 
Section 51.21, the NRC is issuing this Environmental Assessment and 
Finding of No Significant Impact.

Environmental Assessment

Identification of the Proposed Action

    The proposed action would renew Facility Operating License No. R-74 
for a period of 20 years from the date of issuance of the renewed 
license. The proposed action is in accordance with the licensee's 
application dated May 9, 2000, as supplemented by letter dated October 
17, 2008. In accordance with 10

[[Page 56598]]

CFR 2.109, the existing license remains in effect until the NRC takes 
final action on the renewal application.

Need for the Proposed Action

    The proposed action is needed to allow the continued operation of 
the UWNR to routinely provide teaching, research, and services to 
numerous institutions for a period of 20 years.

Environmental Impacts of the Proposed Action

    The NRC has completed its safety evaluation of the proposed action 
to issue a renewed Facility Operating License No. R-74 to allow 
continued operation of the UWNR for a period of 20 years and concludes 
there is reasonable assurance that the UWNR will continue to operate 
safely for the additional period of time. The details of the NRC 
staff's safety evaluation will be provided with the renewed license 
that will be issued as part of the letter to the licensee approving its 
license renewal application. This document contains the environmental 
assessment of the proposed action.
    The UWNR is located in the Mechanical Engineering Building on the 
main campus of the University of Wisconsin. The UWNR is housed in the 
Reactor Laboratory, a 13 meter (43 feet) by 22 meter (70 feet) room of 
conventional construction within the Mechanical Engineering Building. 
Throughout most of the Reactor Laboratory, the ceiling height is 
approximately 11 meters (36 feet) with a portion of the ceiling above 
the console area a height of only 7 meters (22 feet). The floor of the 
room is concrete. There is no basement or crawl space below the Reactor 
Laboratory floor. The walls are concrete and brick. The ceiling is a 
2.25 centimeter (1\1/2\ inch) steel deck with 5 centimeters (2 inches) 
of rigid insulation and a 4-ply, built-up surface roof. The Mechanical 
Engineering Building also contains classrooms, laboratories, shops, and 
staff offices for the Departments of Mechanical Engineering, Industrial 
Engineering, and Engineering Physics. The Mechanical Engineering 
Building is near the southwestern border of the University of Wisconsin 
campus. The nearest property not owned by the University of Wisconsin 
is 130 meters (425 feet) from the reactor site. The reactor site is 700 
meters (2,300 feet) south of the shore of Lake Mendota. The nearest 
permanent residence is approximately 150 meters (485 feet) west of the 
reactor site and the nearest dormitory is approximately 400 meters 
(1,300 feet) away. There are no nearby industrial, transportation, or 
military facilities that pose a threat to the UWNR.
    The UWNR is a heterogeneous pool-type nuclear reactor currently 
fueled with low-enriched uranium TRIGA (Training, Research, Isotope 
Production, General Atomics) fuel which is cooled by natural 
convection. The aluminum-lined concrete pool is 2.5 meters (8 feet) 
wide, 3.7 meters (12 feet) long, and 8.5 meters (27.5 feet) deep. Light 
water acts as the coolant and the moderator as well as being a 
biological shield. The reinforced concrete pool walls also serve as a 
biological shield. The core is reflected on two sides by graphite and 
on two sides by water. The water-reflected areas are being utilized as 
irradiation facility locations. The reactor is shielded by concrete and 
water. The core is normally covered by 6 meters (20 feet) of water. 
Maximum steady-state power level is 1,000 kilowatts. Reactivity is 
controlled by three shim safety blades, a regulating blade, and a 
transient control rod. All control elements move vertically. The top 
and bottom reflector region is partially graphite and partially water. 
A detailed description of the reactor can be found in the licensee's 
Safety Analysis Report.
    On June 11, 2009, the NRC issued an order for UWNR to convert from 
high-enriched uranium fuel to low-enriched uranium fuel (Agencywide 
Documents Access and Management System (ADAMS) Accession No. 
ML091390802). The conversion to low-enriched uranium fuel was completed 
and normal operations resumed on January 22, 2010. As part of the 
analysis for the conversion, the staff determined that the changes 
involved no significant hazards consideration, no significant increase 
in the amount of effluents, no significant change in the type of 
effluents that may be released off site, and no significant increase in 
individual or cumulative occupational radiation exposure.
    The licensee has not requested any further changes to the facility 
design or operating conditions as part of the application for license 
renewal. No significant changes have been made in the types or 
quantities of effluents that may be released offsite.
    The licensee has systems in place for controlling the release of 
radiological effluents and implements a radiation protection program to 
monitor personnel exposures and releases of radioactive effluents. The 
design of the experimental facilities, the reactor pool, and the 
reactor shield includes protective measures and devices which limit 
radiation exposures and limit releases of radioactive material to the 
environment. The systems and radiation protection program are 
appropriate for the types and quantities of effluents expected to be 
generated by continued operation of the reactor. Accordingly, there 
would be no increase in routine occupational or public radiation 
exposure as a result of license renewal. The proposed action will not 
significantly increase the probability or consequences of accidents. 
Therefore, license renewal would not change the environmental impact of 
facility operation. The NRC staff evaluated information contained in 
the licensee's application and data reported to the NRC by the licensee 
for the last five years of operation to determine the projected 
radiological impact of the facility on the environment during the 
period of the renewed license. The NRC staff finds that releases of 
radioactive material and personnel exposures were all well within 
applicable regulatory limits. Based on this evaluation, the NRC staff 
concluded that continued operation of the reactor would not have a 
significant environmental impact.

I. Radiological Impact

Environmental Effects of Reactor Operations

    The radiation protection program at the reactor facility is similar 
to the campus radiation safety program but the reactor program has some 
specific aspects that apply only to the reactor facility. These 
protective measures and devices are discussed more thoroughly in the 
UWNR Safety Analysis Report.
    The ventilation system is designed to prevent the spread of 
airborne particulate radioactive material into occupied areas outside 
the Reactor Laboratory. It removes particulates with high efficiency 
filtration and assures that all releases of both gaseous and 
particulate activity are monitored and discharged at an elevated 
release point. Calculations and measurements have been performed by the 
licensee to determine production and release rates of the various 
activities that might be discharged due to normal operation. Argon-41 
is the only activity released in significant quantities during normal 
operations. The maximum release rate for Argon-41 activity is 13.3 
microCuries per second ([mu]Ci/sec). Using the ventilation system rated 
flow-rate of 9,600 standard cubic feet per minute, this activity is 
diluted to 2.94E-6 microCuries per milliliter ([mu]Ci/ml) at the stack 
outlet. The resulting maximum concentration downwind is calculated to 
be 1.25E-9 [mu]Ci/ml. The maximum release rate of Argon-41 would occur 
with the reactor operating continuously at 1,000 kilowatts and all four 

[[Page 56599]]

ports and the thermal column open. Such operation is not reasonable, 
but it does establish an upper limit to the activity that might be 
discharged. Using the Environmental Protection Agency's (EPA) COMPLY 
program, it was calculated that the maximally exposed receptor, in the 
above-mentioned worst case, would receive a dose of 0.6 millirem/year 
if all activity generated was discharged continuously. Total gaseous 
radioactive releases reported to the NRC in the licensee's annual 
reports were less than the air effluent concentration limits set by 10 
CFR Part 20, Appendix B.
    The only activity produced in liquid form in amounts sufficient to 
present a personnel exposure hazard is Nitrogen-16, which is produced 
in the reactor coolant as it passes through the reactor core when 
operating at power levels above 100 kilowatts. Nitrogen-16 is 
controlled by use of the diffuser system, which reduces the dose rate 
at the pool surface to 2 to 3 millirem/hour during full power 
operation. If the diffuser system fails during full power operation, 
the dose rate at the pool surface is less than 100 millirem/hour. Small 
quantities of liquid radioactive waste are generated by regeneration of 
the demineralizer and from liquids irradiated as part of sample 
irradiation. The radiation level from such liquids is extremely low and 
does not produce radiation exposure hazards. Liquid wastes can be 
transferred to the campus University Safety Department, Radiation 
Safety Office, but most are placed into the holdup tank. The Reactor 
Laboratory occasionally discharges liquid waste from the holdup tank to 
the sewer system. Before discharging liquid waste into the sanitary 
sewer, the discharges are filtered so that no particulate activity 
above 0.5 micron size is discharged. Sampling, analysis, and release of 
the holdup tank contents are governed by a written procedure that 
assures releases are within 10 CFR Part 20 Appendix B Table 3 limits, 
and that the pH of the aqueous liquid is within local limits for 
discharge to the sewer. Annual liquid releases have ranged from 0 to 
10,000 gallons, with 3,000 gallons being typical. The licensee 
maintains a pool leak surveillance program. The pool water leak 
surveillance program continues to monitor the pool water evaporation 
rate, the pool water make-up volume, and pool water radioactivity. The 
pool leak surveillance program indicated that approximately 2,449 
gallons of water have been released to the environment in 2008-2009 and 
736 gallons in 2007-2008. The annual reports for 2006-2007 and 2005-
2006 indicate there was no water released to the environment associated 
with pool surveillance; however, the 2004-2005 annual report indicates 
that water had been released. The radionuclide of concern associated 
with pool water leakage would be hydrogen-3 (tritium). Annual reports 
indicate that the maximum concentrations and maximum quantity released 
from the facility would have no significant impact.
    Annual reports reviewed from the last five years indicate that when 
solid waste is generated from use of the UWNR, it is transferred to the 
University of Wisconsin broad scope license for ultimate disposal in 
accordance with regulations set forth under that license. In the years 
that solid waste was generated, less than 400 milliCuries of solid 
waste was transferred for disposal.
    Dosimeters are used for monitoring operating personnel and 
individuals that frequently conduct experiments. Electronic dosimeters 
are used for visitors and for tour groups. Doses received by visitors 
and tour groups are so low that they are often unmeasurable. The 
maximum dose rate permitted during any tour is 0.5 millirem/hour. The 
maximum dose rate permitted for non-radiation workers is 2.0 millirem/
hour. Visitors who are radiation workers but not part of the campus 
dosimetry program, such as visiting researchers, are allowed access to 
higher dose rates; however, rarely does the dose rate exceed 2.0 
millirem/hour. No student dosimeter has ever received a measurable 
radiation exposure from reactor operation. Occupational exposures 
received by operations and maintenance personnel have historically been 
very low, seldom exceeding 0.5 rem total effective dose equivalent in a 
year and usually below 100 millirem/year. The occupational exposure 
limit for total effective dose equivalent from 10 CFR 20.1201(a)(1)(i) 
is 5 rem per year. No changes that would lead to an increase in 
occupational dose are expected as a result of the proposed action.
    The licensee has in place an environmental monitoring program that 
uses area monitors placed in most volume occupied areas around the 
reactor laboratory. The area monitors are changed out quarterly. The 
exposure reading would indicate the maximum exposure an individual 
would receive if continuously present in that area. Presently, there 
are 26 monitoring points. Effluents are also monitored at the point of 
release. According to the licensee's annual reports, the dose a person 
would receive if continuously present in any of the monitored areas 
would be less than limits set forth in 10 CFR Part 20 for dose to the 
general public.
    The licensee conducts an environmental monitoring program to record 
and track the radiological impact of UWNR operation on the surrounding 
unrestricted area. The program consists of quarterly exposure 
measurements at four locations on the site boundary and at two control 
locations away from any direct influence from the reactor. Review of 
the last five annual reports submitted by the licensee indicates that 
radiation exposure at the monitoring locations were not significantly 
higher than those measured at the control locations. Based on the NRC 
staff's review of the past five years of data, the NRC staff concludes 
that operation of the UWNR does not have any significant radiological 
impact on the surrounding environment. No changes in reactor operation 
that would affect off-site radiation levels are expected as a result of 
the license renewal.

Environmental Effects of Accidents

    Accident analyses are discussed in Chapter 13 of the UWNR Safety 
Analysis Report and updated in the low-enriched uranium conversion 
report dated August 25, 2008 (ADAMS Accession No. ML090760776). The 
maximum hypothetical accident for UWNR is postulated as damage to a 
fuel element resulting in failure of the fuel cladding. The likelihood 
of a major fuel element cladding failure is considered small. The 
elements must meet rigid quality control standards; pool water quality 
is carefully controlled; and care is taken in handling fuel. Though the 
likelihood is small, such a cladding failure is possible. In the event 
of such an accident, the amount of volatiles released to the room would 
be 11.28 Curies. If this activity is distributed uniformly in the 
laboratory volume, the resulting concentration would be 5.18E-3 Ci/
m\3\. The maximum dose to a worker in confinement for 5 minutes would 
be 1.35 rem total effective dose equivalent, 35.8 rem committed dose 
equivalent to the thyroid gland, and 278 millirem effective dose 
equivalent. The proposed action will not result in any changes that 
will increase the probability or consequences of accidents.

II. Non-Radiological Impacts

    The UWNR is cooled by a system that contains three loops: The 
closed loop primary system; the closed loop intermediate coolant 
system; and the closed loop campus chilled water system. Heat from the 
primary coolant system is transferred to the intermediate

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coolant system through the primary heat exchanger. Heat from the 
intermediate cooling system is then transferred to the campus chilled 
water system through the intermediate heat exchanger. The system is 
designed to maintain a pressure gradient towards the pool in order to 
prevent the inadvertent loss of pool water. A 5 centimeter (2 inch) 
diameter line whose rupture could have caused loss of pool water has 
been permanently plugged inside the concrete shield and is presently 
sealed off outside the shield. A pool drain line and valve have been 
eliminated. There are no valves in the system that, if opened, can 
drain the pool. The proposed action would not make any changes that 
would increase the non-radiological consequences of accidents.

National Environmental Policy Act (NEPA) Considerations

    The NRC has responsibilities that are derived from NEPA and from 
other environmental laws, which include the Endangered Species Act 
(ESA), Coastal Zone Management Act (CZMA), National Historic 
Preservation Act (NHPA), Fish and Wildlife Coordination Act (FWCA), and 
the Executive Order on Environmental Justice. The following presents a 
brief discussion of impacts associated with these laws and other 
I. Endangered Species Act
    No effects on the aquatic or terrestrial habitat in the vicinity of 
the facility, or to threatened, endangered, or protected species under 
the Endangered Species Act, would be expected.
II. Coastal Zone Management Act
    The site occupied by the UWNR is not located within any managed 
coastal zones, nor do the UWNR effluents impact any managed coastal 
III. National Historic Preservation Act
    The NHPA requires Federal agencies to consider the effects of their 
undertakings on historic properties. There are a few historic sites 
located on the UW campus within 0.5 miles of the site but the closest 
to the site of the UWNR is the old U. S. Forest Products Laboratory. 
The location of the old U. S. Products Laboratory is approximately 31 
meters (100 feet) from the Mechanical Engineering Building where the 
UWNR is located. Continued operation of the UWNR will not affect this 
historic designation. It is unlikely that there would be any potential 
impacts of license renewal that would have an adverse effect on 
historic and archaeological resources at UWNR.
IV. Fish and Wildlife Coordination Act
    The licensee is not planning any water resource development 
projects, including any of the modifications relating to impounding a 
body of water, damming, diverting a stream or river, deepening a 
channel, irrigation, or altering a body of water for navigation or 
V. Executive Order 12898--Environmental Justice
    The environmental justice impact analysis evaluates the potential 
for disproportionately high and adverse human health and environmental 
effects on minority and low-income populations that could result from 
the relicensing and the continued operation of the UWNR. Such effects 
may include human health, biological, cultural, economic, or social 
impacts. Minority and low-income populations are subsets of the general 
public residing around the UWNR, and all are exposed to the same health 
and environmental effects generated from activities at the UWNR.
    Minority Populations in the Vicinity of the UWNR--According to 2000 
census data, 9 percent of the population (approximately 1,014,000 
individuals) residing within a 50-mile radius of UWNR identified 
themselves as minority individuals. The largest minority groups were 
Black or African American and Hispanic or Latino (32,000 persons or 3.2 
percent), followed by Asian (21,000 or 2.0 percent). According to the 
U.S. Census Bureau, about 12.7 percent of the Dane County population 
identified themselves as minorities, with persons of Black or African 
American origin comprising the largest minority group (6.1 percent). 
According to the census data 3-year average estimates for 2006-2008, 
the minority population of Dane County, as a percent of the total 
population, had increased to 15.5 percent.
    Low-income Populations in the Vicinity of the UWNR--According to 
2000 Census data, approximately 10,500 families and 75,000 individuals 
(approximately 4.1 and 7.4 percent, respectively) residing within a 50-
mile radius of the UWNR were identified as living below the Federal 
poverty threshold in 1999. The 1999 Federal poverty threshold was 
$17,029 for a family of four.
    According to Census data in the 2006-2008 American Community Survey 
3-Year Estimates, the median household income for Wisconsin was 
$52,249, while 7.0 percent of families and 10.7 percent of the state 
population were determined to be living below the Federal poverty 
threshold. Dane County had a higher median household income average 
($61,818) and a lower percent of families (4.6 percent) and similar 
percentage of individuals (10.9 percent) living below the poverty 
level, respectively.
    Impact Analysis--Potential impacts to minority and low-income 
populations would mostly consist of radiological effects; however, 
radiation doses from continued operations associated with this license 
renewal are expected to continue at current levels, and would be well 
below regulatory limits.
    Based on this information and the analysis of human health and 
environmental impacts presented in this environmental assessment, the 
proposed relicensing would not have disproportionately high and adverse 
human health and environmental effects on minority and low-income 
populations residing in the vicinity of UWNR.

Environmental Impacts of the Alternatives to the Proposed Action

    As an alternative to license renewal, the NRC considered denying 
the proposed action. If the NRC denied the request for license renewal, 
reactor operations would cease and decommissioning would be required. 
The NRC notes that, even with a renewed license, the UWNR will 
eventually be decommissioned, at which time the environmental effects 
of decommissioning would occur. Decommissioning would be conducted in 
accordance with an NRC-approved decommissioning plan, which would 
require a separate environmental review under 10 CFR 51.21. Cessation 
of facility operations would reduce or eliminate radioactive effluents 
and emissions. However, as previously discussed in this environmental 
assessment, radioactive effluents and emissions from reactor operations 
constitute a small fraction of the applicable regulatory limits. 
Therefore, the environmental impacts of license renewal and the denial 
of the request for license renewal would be similar. In addition, 
denying the request for license renewal would eliminate the benefits of 
teaching, research, and services provided by the UWNR.

Agencies and Persons Consulted

    In accordance with the agency's stated policy, on July 1, 2010, the 
staff consulted with the State Liaison Officer regarding the 
environmental impact of the proposed action. In an electronic mail 
message dated July 2, 2010, the State Liaison Officer indicated that 
the State had no comments with respect to

[[Page 56601]]

the environmental assessment and for the Finding of No Significant 
    In a communication dated July 9, 2010, the Wisconsin State Historic 
Preservation Office agreed that no historic properties would be 
affected as a result of continued operation of the UWNR.

Finding of No Significant Impact

    On the basis of the environmental assessment, the NRC concludes 
that the proposed action will not have a significant effect on the 
quality of the human environment. Accordingly, the NRC has determined 
not to prepare an environmental impact statement for the proposed 
    For further details with respect to the proposed action, see the 
licensee's letter dated May 9, 2000 (ADAMS Accession No. ML093570404), 
as supplemented by letter dated October 17, 2008 (ADAMS Accession No. 
ML100740573). Documents may be examined, and/or copied for a fee, at 
the NRC's Public Document Room (PDR), located at One White Flint North, 
11555 Rockville Pike (first floor), Rockville, Maryland. Publicly 
available records will be accessible electronically from the ADAMS 
Public Electronic Reading Room on the NRC Web site http://www.nrc.gov/reading-rm/adams.html. Persons who do not have access to ADAMS or who 
encounter problems in accessing the documents located in ADAMS should 
contact the NRC PDR Reference staff at 1-800-397-4209, or 301-415-4737, 
or send an e-mail to [email protected].

    Dated at Rockville, Maryland, this 10th day of September 2010.

    For the Nuclear Regulatory Commission.
Linh Tran,
Senior Project Manager, Research and Test Reactors Licensing Branch, 
Division of Policy and Rulemaking, Office of Nuclear Reactor 
[FR Doc. 2010-23114 Filed 9-15-10; 8:45 am]