[Federal Register Volume 66, Number 213 (Friday, November 2, 2001)]
[Notices]
[Pages 55703-55709]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-27716]



[[Page 55703]]

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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-331]


Nuclear Management Company, LLC; Duane Arnold Energy Center 
Environmental Assessment and Finding of No Significant Impact Related 
to a Proposed License Amendment To Increase the Maximum Rated Thermal 
Power Level

    The U.S. Nuclear Regulatory Commission (NRC) is considering 
issuance of an amendment to Facility Operating License No. DPR-49, 
issued to Nuclear Management Company, LLC (NMC), for operation of the 
Duane Arnold Energy Center, located in Linn County, Iowa. Therefore, 
pursuant to 10 CFR 51.21 and 10 CFR 51.35, the NRC is issuing this 
environmental assessment and finding of no significant impact.

Environmental Assessment

Identification of the Proposed Action

    The proposed action would allow NMC, the operator of DAEC, to 
incrementally increase its electrical generating capacity by raising 
the maximum reactor core power level from 1658 MWt to 1912 MWt, 15.3 
percent above the current maximum licensed power level. The change is 
considered an EPU for a BWR because it would raise the reactor core 
power level more than approximately 7 percent above the original 
maximum licensed power level. A previous 4.1-percent power uprate, 
implemented in 1985, raised the original maximum power level from 1593 
MWt to 1658 MWt. A power uprate increases the heat output of the 
reactor to support increased turbine inlet steam flow requirements and 
increases the heat dissipated by the condenser to support increased 
turbine exhaust steam flow requirements.
    The proposed action is in accordance with NMC's application for 
amendment dated November 16, 2000, as supplemented April 16 (two 
letters) and 17; May 8 (two letters), 10, 11 (two letters), 22, and 29; 
June 5, 11, 18, 21, and 28; July 11, 19, and 25; and August 1, 10, 16, 
and 21; and October 17, 2001, and NMC's ``Supplement to DAEC 
Environmental Report,'' submitted on September 22, 2000, in advance of 
the application.
    The NRC previously published a draft environmental assessment of 
the proposed action in the Federal Register (66 FR 48482, September 20, 
2001) and offered an opportunity for public comment. No comments were 
received.

Need for the Proposed Action

    Alliant Energy--IES Utilities (Alliant), the principal owner of 
DAEC,\1\ has compared the projected load growth to its electrical 
generating capacity and has determined a need for additional capacity 
in its territory. Alliant's obligated capacity is expected to increase 
by 2 percent per year. The proposed EPU would add 80 megawatts of 
electrical generating capacity to the grid. The estimated cost of 
adding this generating capacity is approximately half the cost of 
purchasing power and one-third the cost of providing the power by 
constructing a new combined-cycle, natural-gas-fueled facility. 
Therefore, Alliant concluded that increasing DAEC's capacity would be 
the most economical option for increasing power supply. Furthermore, 
unlike fossil fuel plants, DAEC does not routinely emit sulfur dioxide, 
nitrogen oxide, carbon dioxide, or other atmospheric pollutants.
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    \1\ On January 10, 2001, the NRC published in the Federal 
Register (66 FR 2009) an Environmental Assessment and Finding of No 
Significant Impact regarding a requested change to the DAEC 
operating license to reflect the proposed change in the owner's name 
from IES Utilities, Inc., to Interstate Power and Light Company. The 
NRC's final action regarding the requested name change is pending.
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Environmental Impacts of the Proposed Action

    At the time of the issuance of the operating license for DAEC, the 
NRC staff noted that any activity authorized by the license would be 
encompassed by the overall action evaluated in the Final Environmental 
Statement (FES) for the operation of DAEC, which was issued in March 
1973. The original operating license for DAEC allowed a maximum reactor 
power level of 1593 MWt. On September 22, 2000, NMC submitted a 
supplement to its Environmental Report supporting the proposed EPU 
action and provided a summary of its conclusions concerning the 
environmental impacts of the proposed action. Based on the NRC staff's 
independent analyses of the nonradiological and radiological impacts 
and the evaluation performed by the licensee, the staff has concluded 
that the environmental impacts of the EPU are bounded by the 
environmental impacts previously evaluated in the FES because the EPU 
does not involve extensive changes to plant systems that directly or 
indirectly interface with the environment. Additionally, the licensee 
states that no changes to the National Pollutant Discharge Elimination 
System permit issued by the State would be necessary.

Nonradiological Impacts

    The following is the NRC staff's evaluation of the nonradiological 
environmental impacts of the EPU on land use, water use, waste 
discharges, terrestrial and aquatic biota, transmission facilities, and 
social and economic conditions at DAEC.

Land Use Impacts

    The proposed EPU would not modify the land use at the site, nor 
have any impacts on lands with historic or archaeological significance. 
The licensee states that it has no plans to construct any new 
facilities or alter the land around existing facilities, including 
buildings, access roads, parking facilities, laydown areas, onsite 
transmission and distribution equipment, or power line rights-of-way, 
in conjunction with the EPU. The EPU would not significantly affect the 
storage of materials, including chemicals, fuels, and other materials 
stored above or under the ground. The EPU would not alter the 
aesthetics of the site. Therefore, the FES conclusions for impacts on 
land use would remain valid under EPU conditions.

Water Use Impacts

    The staff evaluated surface water use and groundwater use as 
environmental impacts of water usage at DAEC.
Surface Water Use
    An EPU is accomplished by increasing the heat output of the 
reactor, thereby increasing the steam flow to the turbine, for which 
increased feedwater flow is needed. The increased heat load on the 
cooling tower would cause evaporative losses to increase; therefore, 
cooling tower makeup to the circulating water system increases to 
compensate for the increase in evaporative losses. Cooling tower makeup 
at DAEC is supplied by the Cedar River and well water systems. The EPU 
would not change the amount of water withdrawn from the well water 
system. The EPU would require an increase in river water use; however, 
the licensee stated that DAEC would not use more river water than 
permitted. In accordance with the water appropriation limits of the 
Iowa Department of Natural Resources (IDNR), DAEC may withdraw a 
maximum of 12,575 million gallons per year (MGY) from the Cedar River 
at a rate of 27,000 gallons per minute (gpm) minus the total well water 
withdrawal rate (3000 gpm). Special operating restrictions apply at 
lower-than-average river flows if the withdrawal would reduce the river 
flow to less than 500 cubic feet per second (cfs). A maximum flow rate 
of 11,000 gpm and an annual

[[Page 55704]]

withdrawal rate of 5782 MGY were analyzed in the FES. During the years 
1996 through 1999, the flow at DAEC averaged 5680 gpm. The licensee 
predicts the flow will be 6700 gpm under EPU conditions. The predicted 
flow average under EPU conditions is approximately 40 percent less than 
that analyzed in the FES and is below the IDNR-permitted limits. In the 
period 1996-1999, the annual withdrawal rate at DAEC averaged 3000 MGY; 
the licensee projects it will be 3540 MGY under EPU conditions. The 
3540 MGY projected average flow withdrawal rate is also below the value 
evaluated in the FES and the IDNR-permitted limit of 12,575 MGY. The 
EPU would have no impact on the number of cooling tower concentration 
cycles or on the cooling tower flow rate. Therefore, current water 
appropriation limits would be maintained and the conclusions in the FES 
would remain valid under the proposed EPU conditions.
Groundwater Use
    The staff evaluated the consumption of groundwater as an 
environmental impact of the proposed EPU. Groundwater use at DAEC is 
governed by a permit issued by the IDNR. The permit limits DAEC to 1575 
MGY with the flow from all pumps not to exceed 3000 gpm. A maximum flow 
rate of 1500 gpm and a withdrawal rate of 788 MGY were evaluated in the 
FES. The average annual groundwater withdrawal rate for DAEC is 762 
MGY, with a normal system flow averaging 1420 gpm.
    The licensee stated that the proposed EPU would not increase the 
consumption of groundwater, would not impact the well water system flow 
path, and does not require any additional cooling capacity from the 
groundwater in order to shed heat loads. Therefore, the staff's 
conclusions in the FES on groundwater use are valid for the proposed 
EPU.

Discharge Impacts

    The staff evaluated environmental impacts such as cooling tower 
fogging, icing, drift, noise, chemical discharges to surface water, 
sanitary waste discharges, blowdown, thermal plume spread, temperature 
of the river water, cold shock to aquatic biota, hazardous waste 
effluents, and air emissions.
Cooling Tower Fogging, Icing, Drift, and Noise
    Environmental impacts such as fogging, icing, cooling tower drift, 
and noise could result from the increased heat load on the cooling 
tower under EPU conditions. In the FES, the staff concluded that the 
operation of the DAEC cooling towers may slightly increase fogging and 
icing in nearby areas. The staff stated that cooling tower drift was 
estimated to be a maximum of 0.1 percent of cooling water flow, or 0.65 
cubic feet per second (290 gpm). The estimates were based on 
anticipated evaporation and drift rates of 2.25 percent and 0.5 percent 
of tower flow, respectively. The licensee stated that the total hours 
of fogging would increase by approximately 1.1 hour per year above the 
nominal 240 hours per year, and that icing would be insignificant. The 
proposed EPU would not change the cooling tower flow or drift rate; 
however, the evaporation rate was calculated to increase to 
approximately 3 percent.
    Since the original analysis in the FES, the cooling towers at DAEC 
have been upgraded by replacing the wooden drift eliminators with 
polyvinyl chloride (PVC) drift eliminators. The PVC drift eliminators 
allow water droplets to return to the cooling tower air stream and 
channel water to the cooling tower's cold water basin, which reduces 
evaporation and drift losses. Consequently, the licensee's analysis of 
the effect of the EPU on fogging is conservative.
    After considering the increase in heat load on the cooling towers, 
the staff concluded that the incremental effects of fog attributable to 
the proposed EPU would be negligible and would continue to be bounded 
by the FES. Other cooling tower impacts, such as drift and icing, would 
not be expected to change as a result of the EPU. Therefore, the staff 
finds that the conclusions in the FES for fogging, icing, and cooling 
tower drift would be valid under the proposed EPU conditions.
    The FES also stated that the operation of the cooling towers would 
result in a noticeable, but acceptable, increase in the noise level at 
the nearest dwelling. The proposed EPU would not significantly change 
the character, sources, or energy of noise generated at DAEC. The new 
equipment necessary to implement the EPU would be installed within 
existing plant buildings and no significant increase in ambient noise 
levels within the plant would be expected. Therefore, the FES 
conclusions for noise levels would remain valid under EPU conditions.
Chemical and Sanitary Discharges
    Surface water and wastewater discharges are regulated by the State 
of Iowa. The National Pollutant Discharge Elimination System (NPDES) 
permit is periodically reviewed and reissued by the IDNR. The present 
NPDES permit for DAEC authorizes discharges from two outfalls, only one 
of which would be affected by the EPU.
    The use of chemicals and their subsequent discharge to the 
environment would not be expected to change significantly as a result 
of the proposed EPU. The cooling tower concentration cycle would remain 
within the current range of 3.5 to 4.0. Therefore, the concentration of 
pollutants in the effluent stream would remain the same. No changes to 
the sanitary waste systems or to the parameters regulated by the NPDES 
permit would be needed to accomplish the EPU. Sanitary waste from DAEC 
is discharged directly to the DAEC sewage treatment plant in accordance 
with a permit from the State of Iowa.
Blowdown
    Total discharge would increase linearly with blowdown flow. It is 
anticipated that the blowdown flow would increase 18 percent as a 
result of the EPU. Blowdown for the circulating water system is 
discharged into the Cedar River. The FES conservatively assumed a 
blowdown flow rate of 4000 gpm. The actual blowdown flow rate is 1570 
gpm and the blowdown flow rate calculated for EPU conditions would be 
1850 gpm. During winter, the season which DAEC discharges would have 
the greatest impact on river water temperature, the actual average 
blowdown temperature is 30 degrees Fahrenheit ( deg.F) less than that 
assumed in the FES. The EPU would increase the blowdown discharge 
temperature by approximately 1.6  deg.F. Typical discharge temperatures 
and flow rates are below the current limits so it would not be 
necessary to modify the NPDES permit to implement the proposed EPU.
Thermal Plume Spread and Temperature of River Water
    The actual average blowdown flow rate is 1,570 gpm. The FES assumed 
a value of 4,000 gpm. The increased values for uprated power blowdown 
temperature and flow are still bounded by the calculation of the FES. 
Consequently, the FES conclusions remain valid. The FES concluded that 
the thermal plume would be less than 1 acre in area and would reach 
less than a quarter of the reach across the river. The EPU would 
increase the discharge temperature by 1.6  deg.F and the flow rate by 
18 percent. However, the EPU would not noticeably increase the plume 
size.
    Under worst-case winter conditions, the 2  deg.F isotherm was 
predicted to extend about 250 feet downstream with a width of about 70 
feet. A discharge temperature of 72  deg.F for the month of

[[Page 55705]]

January was analyzed in the FES. Historically, in winter, when 
discharges would have the greatest impact on river water temperature, 
the actual average blowdown temperature is 30  deg.F less than that 
assumed in the FES. The average discharge temperature (from 1961 to 
1990) for the month of January was 36  deg.F, and, as stated above, the 
EPU would increase the discharge temperature by only 1.6  deg.F. 
Consequently, the actual size of the thermal plume is smaller than 
predicted in the FES.
    Under worst-case summer conditions, with the same assumptions and 
data used to calculate the circulating water discharge temperature, the 
2  deg.F isotherm was predicted to extend about 75 feet downstream of 
the discharge point with a width of about 35 feet. Thermal mapping 
conducted in August 1989, demonstrated the conservative nature of the 
assumptions in the FES. The mapping was performed at 100-percent 
reactor power. The 2  deg.F isotherm extended to between 100 and 150 
feet downstream, and was restricted to within 10 feet of the bank (i.e. 
10 feet wide). At 150 feet downstream, there was no detectible plume. 
The total plume area was less, therefore, than that predicted for the 2 
 deg.F isotherm in the FES, and, as stated above, the EPU would not 
noticeably increase the plume size. The staff concludes the plumes for 
both summer and winter cases are bounded by the FES. The conditions 
analyzed in the FES would be expected to remain valid under the 
proposed EPU conditions.
Cold Shock
    Cold shock to an aquatic biota occurs when the warm water discharge 
from a plant abruptly stops because of an unplanned shutdown, resulting 
in a temperature drop of the river water and the possible adverse 
impact on aquatic biota. The probability of an unplanned shutdown is 
independent of a power uprate. As discussed previously, the discharge 
canal temperature at EPU conditions would be at least 10  deg.F less 
than the value evaluated in the FES. Additionally, the plume size would 
not increase appreciably under power uprate conditions and would be 
smaller than analyzed in the FES. Therefore, the risk of aquatic biota 
mortality by cold shock would continue to be bounded by the conclusions 
in the FES.
Hazardous Waste Generation and Air Emissions
    Hazardous waste generated from routine plant operations and air 
emissions from the plant heating boiler and diesel generators are 
controlled by county permits. A power uprate would not have a 
significant impact on the quality or quantity of effluents from these 
sources, and operation under EPU conditions would not reduce the margin 
to the limits established by the applicable permits. Therefore, the 
conclusions in the FES would remain valid.

Terrestrial Biota Impacts

    The proposed EPU would not result in a land disturbance that could 
adversely impact the habitat of any terrestrial plant or animal 
species. The licensee stated that according to a recent review by the 
IDNR, there were no known rare or endangered terrestrial species within 
the area of the site boundary. Additionally, the licensee stated that 
land use would remain the same as evaluated in the FES. Therefore, the 
staff's conclusions in the FES about the impact on terrestrial ecology, 
including endangered and threatened plant and animal species, would 
remain valid for the proposed EPU.

Aquatic Biota Impacts

    The impacts of operation of the river water intake include 
impingement of fish on the traveling screens at the intake structure 
and the entrainment of benthic organisms. The losses associated with 
the impingement and entrainment of organisms were assessed in the FES 
and were judged to be insignificant. The effect of the EPU on the 
impingement and entrainment of organisms also would be insignificant. 
Fish impingement totals are typically less than 500 fish per year and 
are considered to be very low, considering the size and composition of 
the fish population in the Cedar River. Additionally, the licensee 
stated that there were no known rare or endangered aquatic species in 
the plant site vicinity. Therefore, the staff's conclusions in the FES 
as to impingement, entrainment, and endangered and threatened aquatic 
species would remain valid for the proposed EPU.

Transmission Facility Impacts

    Environmental impacts, such as exposure to electromagnetic fields 
(EMFs) and shock could result from a major modification to transmission 
line facilities. However, the licensee stated that no change would be 
made to the existing transmission line design or operation as a result 
of the proposed EPU. Higher main transformer capacity would be 
necessary to deliver the additional power to the offsite grid and 
certain modifications to offsite substations are being planned to 
enhance stability at various grid locations. These modifications are 
consistent with Alliant's program of systematic improvements in grid 
stability and its commitments to the Mid-Continent Area Power Pool and 
the Mid-America Interconnected Network; modifications would be 
performed within existing substations. Therefore, no significant 
environmental impacts from any changes in transmission facilities 
design and equipment are expected, and the conclusions in the FES would 
remain valid.
    The rise in generator output associated with EPU would slightly 
increase the current and the EMFs in the onsite transmission line 
between the main generator and the plant substation. The line is 
located entirely within the fenced, licensee-controlled boundary of the 
plant, and neither members of the public nor wildlife are expected to 
be affected. Exposure to EMFs from the offsite transmission system is 
not expected to increase significantly and any such increase is not 
expected to change the staff's conclusion in the FES that no 
significant biological effects are attributable to EMFs from high 
voltage transmission lines.
    DAEC transmission lines are designed and constructed in accordance 
with the applicable shock prevention provisions of the National 
Electric Safety Code and the EPU would not cause the transmission line 
design to deviate from the NESC provisions. Therefore, the slight 
expected increase in current attributable to the proposed EPU does not 
change the staff's conclusion in the FES that adequate protection is 
provided against hazards from electrical shock.

Social and Economic Impacts

    The staff has reviewed information provided by the licensee 
regarding socioeconomic impacts, including possible impacts on the DAEC 
workforce and the local economy. DAEC employs more than 500 people and 
is a major contributor to the local tax base. DAEC personnel also 
contribute to the tax base by paying sales and property taxes. The 
proposed EPU would not significantly affect the size of the DAEC 
workforce and would have no material effect on the labor force required 
for future outages. Because the plant modifications needed to implement 
the EPU would be minor, any increase in sales taxes and local and 
national business revenues would be negligible relative to the large 
taxes paid by DAEC. It is expected that improving the economic 
performance of DAEC through cost reductions and lower total bus bar 
costs per kilowatt hour would enhance the value of DAEC as a generating 
asset

[[Page 55706]]

and lower the probability of early plant retirement. Early plant 
retirement might have a negative impact upon the local economy and the 
community as a whole by reducing public services, employment, income, 
business revenues, and property values, although these reductions might 
be mitigated by decommissioning activities in the short term. The staff 
expects that conclusions in the FES regarding social and economic 
impacts would remain valid under EPU conditions.
    The staff also considered the potential for direct physical impacts 
of the proposed EPU, such as vibration and dust from construction 
activities. The proposed EPU would be accomplished primarily by changes 
in station operation and a few physical modifications to the facility. 
These limited modifications would be accomplished without physical 
changes to transmission corridors, access roads, other offsite 
facilities, or additional project-related transportation of goods or 
materials. Therefore, no significant additional construction 
disturbances causing noise, odors, vehicle exhaust, dust, vibration, or 
shock from blasting are anticipated, and the conclusions in the FES 
would remain valid.

Summary

    In summary, the proposed EPU would not result in a significant 
change in nonradiological impacts on land use, water use, waste 
discharges, terrestrial and aquatic biota, transmission facilities, or 
social and economic factors, and would have no nonradiological 
environmental impacts other than those evaluated in the FES.

 Table 1.--Summary of Nonradiological Environmental Impacts of an EPU at
                                  DAEC
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Land Use Impacts.............  No change in land use or aesthetics;
                                would not impact lands with historic or
                                archeological significance.
Water Use Impacts:
    Surface Water Use........  Increase in river water withdrawal rate
                                to 3540 MGY; withdrawal rate would
                                remain within permitted levels, and
                                within levels evaluated in the FES.
    Groundwater Use..........  No change in groundwater use.
Discharge Impacts:
    Fogging..................  Increase in total hours of fogging per
                                year by 1.1 hour.
    Icing....................  No significant change in icing.
    Cooling Tower Drift......  No significant change in cooling tower
                                drift.
    Noise....................  No significant change in noise.
    Chemical and Sanitary      No expected change to chemical use and
     Discharge.                 subsequent discharge, or sanitary waste
                                systems; cooling towers would operate in
                                the current cycle range. No changes to
                                sanitary waste discharges.
    Blowdown.................  Increase in blowdown by 18 deg.; blowdown
                                would remain within the permitted
                                limits.
Thermal Plume and Temperature  No noticeable increase in thermal plume
 of the River Water.            size. Discharge temperature increase by
                                1.6 EF; river temperature would remain
                                within National Pollution Discharge
                                Elimination System limit of 9  deg.F.
    Hazardous Waste and Air    No changes to hazardous waste sources or
     Emissions.                 air emissions.
Terrestrial Biota Impacts....  No change in terrestrial biota impacts;
                                no known threatened or endangered
                                species within the site boundary.
Aquatic Biota Impacts........  No change in aquatic biota impacts; no
                                known threatened or endangered species
                                in the area of surface water intake or
                                discharge.
Transmission Line Facility     No change to transmission line design or
 Impacts.                       operation; higher main transformer
                                capacity would be needed to deliver
                                additional power and these changes would
                                be made within existing substations; no
                                change in exposure to EMFs.
Social and Economic Impacts..  No significant change in size of DAEC
                                workforce. Few modifications to physical
                                station facility. No significant
                                disturbances from noise, odor, vehicle
                                exhaust, dust, vibration, or shock would
                                be expected from construction.
------------------------------------------------------------------------

Radiological Impacts

    The staff evaluated radiological environmental impacts on waste 
streams, in-plant and offsite doses, accident analyses, and fuel cycle 
and transportation factors. The following is a general description of 
the waste treatment streams at DAEC and an evaluation of the 
environmental impacts.

Radioactive Waste Stream Impacts

    DAEC uses waste treatment systems designed to collect, process, and 
dispose of radioactive gaseous, liquid, and solid waste in accordance 
with the requirements of 10 CFR part 20 and Appendix I to 10 CFR part 
50. These radioactive waste treatment systems are discussed in the FES. 
The proposed EPU would not affect the environmental monitoring of these 
waste streams or the radiological monitoring requirements contained in 
licensing basis documents. The proposed EPU would not result in any 
changes in operation or design of equipment in the gaseous, liquid, or 
solid waste systems. The proposed EPU would not introduce new or 
different radiological release pathways and would not increase the 
probability of an operator error or equipment malfunction that would 
result in an uncontrolled radioactive release. The staff evaluated any 
changes in the gaseous, liquid, and solid waste streams for 
radiological environmental impact of the proposed EPU, as set forth 
below.
Gaseous Radioactive Waste Impacts
    During normal operation, the gaseous effluent systems control the 
release of gaseous radioactive effluents to the site environs, 
including small quantities of noble gases, halogens, particulates, and 
tritium, so that routine offsite releases from station operation remain 
below the limits of 10 CFR part 20 and appendix I to 10 CFR part 50 (10 
CFR part 20 includes the requirements of 40 CFR part 190). The gaseous 
waste management systems include the offgas system and various building 
ventilation systems. The proposed EPU assumes an increase in the 
release rate that is linearly proportional to power increase, and an 
increase in gaseous effluents would, therefore, occur. The resultant 
effluent increases in noble gas and iodine-131 activity are 0.3 and 4E-
07 microcuries per second, respectively. The staff has evaluated 
information provided by the licensee and concludes that the estimated 
dose values would be below Appendix I requirements after the EPU. These 
dose levels are very small,

[[Page 55707]]

and have no significant impact on human helath. The effluents for noble 
gases and effluents are well below those evaluated in the FES. 
Therefore, the conclusions in the FES would remain valid under EPU 
conditions.
Liquid Radioactive Waste Impacts
    The liquid radwaste system is designed to process and recycle (to 
the extent practicable) the liquid waste collected so that annual 
radiation doses to individuals are maintained below the guidelines in 
10 CFR Part 20 and 10 CFR Part 50, Appendix I. DAEC operates as a zero 
radioactive liquid release plant. The staff expects no change in the 
zero release policy as a result of the proposed EPU.
    Filter backwashing provides decanted sludge water into the liquid 
radwaste system. Increasing the reactor thermal power by 15 percent 
would increase the frequency of backwashing necessary to decant 
backwash water from the reactor water cleanup condensate demineralizer 
filters by approximately 8 to 10 percent. However, since Alliant 
maintains a zero radioactive liquid release to the environment, the 
slight increase in flow to the liquid radwaste system would be recycled 
instead of discharged.
    The EPU conditions would not result in significant increases in the 
volume of fluid from other sources flowing into the liquid radwaste 
system. The reactor would continue to be operated within its present 
pressure control band. Valve packing leakage volume into the liquid 
radwaste system is not expected to increase. There would be no changes 
in reactor recirculation pump seal flow or the flow of any other normal 
equipment drain path. In addition, there would be no impact on the 
dirty radwaste or chemical waste subsystems of the liquid radwaste 
system as a result of the EPU since the operation and the inputs to 
these subsystems are independent of power uprate. Based on information 
submitted by the licensee, the staff concludes that no significant dose 
increase in the liquid pathway would result from the proposed EPU. 
Therefore, the conclusions in the FES would remain valid under EPU 
conditions.
Solid Radioactive Waste Impacts
    The solid radioactive radwaste system collects, monitors, 
processes, packages, and provides temporary storage facilities for 
radioactive solid wastes prior to offsite shipment and permanent 
disposal. DAEC has implemented procedures to assure that the processing 
and packaging of wet and dry solid radioactive waste and irradiated 
reactor components are accomplished in compliance with the regulations.
    Wet Waste: The largest volume contributors to radioactive solid wet 
waste are the spent resin and filter sludges from the process wastes. 
Equipment waste from operation and maintenance activities, chemical 
wastes, and reactor system wastes also contribute to solid waste 
generation. The staff expects that the process wastes generated from 
the operation of the reactor water cleanup filter demineralizers and 
the condensate demineralizers will increase by no more than 10 percent. 
More frequent reactor water cleanup backwashes are anticipated under 
EPU conditions due to water chemistry limits. The licensee estimates 
that the backwashes would increase by approximately 8 to 10 percent, 
resulting in an additional 3 cubic meters of resin waste per year. The 
resultant total generation rate of approximately 36 cubic meters per 
year (CMY), is about half the current industry median value of 85 CMY 
and well below the FES assumed value of 697 CMY. The EPU would not 
involve changes in either reactor water cleanup flow rates or filter 
performance. The staff concludes that implementation of the proposed 
EPU would not have a significant impact on the volume or activity of 
wet radioactive solid waste at DAEC.
    Dry Waste: Dry waste consists of air filters, miscellaneous paper 
and rags from contaminated areas, contaminated clothing, tools and 
equipment parts that cannot be effectively decontaminated, and solid 
laboratory wastes. The activity of much of this waste is low enough to 
permit manual handling. Dry waste is collected in containers located 
throughout the plant, compacted as practicable, and then sealed and 
removed to a controlled-access enclosed area for temporary storage. 
Because of its low activity, dry waste can be stored until enough is 
accumulated to permit economical transportation to an offsite 
processing facility or a burial ground for final disposal. DAEC has 
indicated that there will be no significant change in the amounts, 
level of controls, or methodology used for the processing dry 
radioactive waste at DAEC. The staff concludes that implementation of 
the proposed EPU should not have a significant impact on the volume or 
activity of the dry solid radioactive waste at DAEC.
    Irradiated Reactor Components: Irradiated reactor components, such 
as spent control blades, in-core ion chambers, and fuel assemblies, 
must be disposed of after the life of the component. The volume and 
activity of waste generated from spent control blades and in-core ion 
chambers might increase slightly under the higher flux conditions 
associated with power uprate conditions. This increase would be 
mitigated by improved longer-lived local power range monitor strings, 
improved lower-cobalt-content control rod blades, and longer fuel 
cycles. Additionally, reactor equipment waste is stored in the spent 
fuel storage pool before removal to in-plant or offsite storage and 
final disposal in shielded containers or casks. Because of the 
mitigating effects of extended burnup and increased U-235 enrichment 
compared to the burnups and enrichment evaluated in the original FES, 
implementing the EPU would not be likely to have a significant impact 
on the amount of irradiated reactor components discharged from the 
reactor.
    DAEC plans to load 152 fresh fuel bundles in the initial refueling 
to commence operation under the EPU. This is approximately 30 bundles 
more than for the current refueling cycle. Because of the mitigating 
effects of extended burnup and increased U-235 enrichment on fuel 
throughput under power uprate operating conditions, the number of 
irradiated fuel assemblies discharged from the reactor would not 
increase during subsequent reloads. Additionally, the 24-month 
operating cycle would result in one less fuel reload before the license 
expiration. These wastes are currently stored in the spent fuel pool 
and are not shipped off site. The staff concludes that implementation 
of the proposed EPU should not have a significant impact on the volume 
or activity of the irradiated reactor components at DAEC.
    The staff has generically evaluated the annual environmental impact 
of low- and high-level solid wastes for a 1000 MWe reference reactor. 
The estimated activity of these wastes is given in Table S-3 in 10 CFR 
51.51 and would be bounding under the proposed EPU conditions.

Dose Impacts

    The staff evaluated in-plant and offsite radiation as part of its 
review of environmental impacts of the proposed EPU.
In-Plant Radiation
    Increasing the rated power at DAEC might increase the radiation 
levels in the reactor coolant system; however, these potential 
increases would be compensated for by physical plant improvements and 
administrative controls, such as shielding, feedwater chemistry, and 
the plant radiation

[[Page 55708]]

protection program. Over the past 7 years, DAEC has decreased the 
occupational dose to DAEC workers by 15 percent per year (based on a 
rolling 3-year average). The licensee stated that it expects to 
continue its downward trend while operating under the proposed EPU 
conditions. The staff evaluated shielding, dose reduction programs, and 
corrosion as part of its evaluation.
    Shielding: DAEC was conservatively designed with respect to 
shielding and radiation sources. In the shielding analysis, the assumed 
concentrations for reactor water fission and corrosion products were 4 
microcuries per cubic centimeter and 0.06 microcuries per cubic 
centimeter, respectively. The normal value of both reactor water 
fission and corrosion products is 0.01 microcuries per cubic 
centimeters. With expected increases in operating activity proportional 
to the proposed power increase, the design shielding assumptions remain 
bounding at EPU conditions.
    Feedwater Chemistry: The original design was based on an assumed 
value for nitrogen-16 (N-16) concentration of 100 microcuries per gram. 
To support the injection of hydrogen into the feedwater, the licensee 
conducted a special test in 1989 to evaluate the impact and efficacy of 
injection rates of up to 45 standard cubic feet per minute (scfm). The 
licensee stated that the results of this test led to an injection rate 
of 6 scfm, which yields an acceptable recirculating system 
electrochemical potential and no discernable N-16 dose rate increase. 
Between October 1994 and October 1996, the hydrogen injection rate was 
increased to 15 scfm to extend corrosion protection to portions of the 
core internals, with a resultant increase in dose rates of 3.3 times 
the rates without hydrogen injection. Although occupancy in some areas 
was restricted, no shielding modifications were required to maintain 
radiation levels within acceptable levels. Since 1996, DAEC has 
undertaken a noble metals injection program to protect the core 
internals from corrosion by reducing hydrogen use. As a result, the 
current operational hydrogen injection rate is 6.0 scfm. The 20-percent 
increase in the N-16 dose rate from EPU would not affect the 
acceptability of the shielding design.
    The equilibrium activity concentration of corrosion products that 
have plated out on reactor coolant piping and other surfaces may 
theoretically increase by the square of the power uprate increase. This 
is primarily due to the linear increase in corrosion products in the 
primary system from the feedwater flow increase and the linear increase 
in activation events from the core average flux increase. However, this 
potential increase would be mitigated by four dose reduction programs 
at DAEC:
    1. Oxygen injection in the condensate system started in 1987.
    2. Recirculating system chemical decontaminations in 1990, 1992, 
1993, and 1995.
    3. Stellite reduction efforts started in 1993.
    4. Depleted zinc addition started in 1994.
    As a result of these efforts, the concentration of soluble cobalt-
60 in the reactor water has decreased from 1.3E-04 microcuries per 
milliliter in early 1987 to 2.7 E-05 microcuries per milliliter in 
2000. The potential increases in the volume and activity of activated 
corrosion products at EPU operating conditions would not negate these 
efforts, and it is expected that concentrations would continue to 
decline under EPU conditions. Consequently, operating and shutdown 
radiation levels would not increase under EPU conditions.
    Plant Radiation Protection Program: The plant radiation protection 
program would be used to maintain individual doses consistent with as-
low-as-reasonably-achievable policies and below the established limits 
of 10 CFR Part 20. Routine plant radiation surveys required by the 
radiation protection program would identify increased radiation levels 
in accessible areas of the plant, and radiation zone postings and job 
planning would be adjusted, if necessary. Time within radiation areas 
is controlled under the radiation protection program. Administrative 
dose control limits are established well below regulatory criteria and 
provide a significant margin to regulatory dose limits. The licensee 
stated that administrative dose limits were not routinely exceeded 
under present power conditions.
    On the basis of the above information, the staff concludes that the 
expected annual collective dose for DAEC, following the proposed EPU, 
would still be bounded by the dose estimates in the FES.

Offsite Doses

    The slight increase in normal operational gaseous activity levels 
under the EPU would not affect the large margin to the offsite dose 
limits established by 10 CFR Part 20. In addition, doses from liquid 
effluents, currently zero, would remain zero under EPU conditions.
    The DAEC Technical Specifications implement the guidelines of 10 
CFR Part 50, Appendix I, which are within the 10 CFR Part 20 limits. 
Adjusting current values for projected EPU increases, the offsite dose 
at EPU conditions is estimated to be 2.6 E-03 millirads for noble gas 
gamma air, 1.6E-02 millirads for noble gas beta air, and 6.8E-03 
thyroid millirem for particulates and iodine. The Appendix I limits are 
10 millirads, 20 millirads, and 15 thyroid millirem, respectively. The 
offsite dose would continue to be within the Technical Specification 
dose limits.
    The EPU would not involve significant increases in an offsite dose 
from noble gases, airborne particulates, iodine, or tritium. 
Radioactive liquid effluents are not routinely discharged from DAEC. In 
addition, as stated by the Radiological Environmental Monitoring 
Program for DAEC, radiation from shine is not now a significant 
exposure pathway, and it would not be significantly affected by the 
proposed EPU.
    The EPU would not create any new or different sources of offsite 
dose from DAEC operation, and the EPU would not involve significant 
increases in present radiation levels. Therefore, under EPU conditions, 
offsite dose would remain well within regulatory criteria and would not 
have a significant impact. The staff concludes that the estimated doses 
from both the liquid and gaseous release pathways resulting from EPU 
conditions are within the design objectives specified by 10 CFR part 
50, appendix I, and the limits of 10 CFR part 20.

Accident Analysis Impacts

    The staff reviewed the licensee's analyses and performed 
confirmatory calculations to verify the acceptability of the licensee's 
calculated doses under accident conditions. The staff concludes that 
the proposed EPU would not significantly increase the probability or 
consequences of accidents and would not result in a significant 
increase in the radiological environmental impact of DAEC under 
accident conditions. If the license amendment request is approved, the 
result of the staff's calculations will be presented in the safety 
evaluation issued with the license amendment.

Fuel Cycle and Transportation Impacts

    The EPU would involve an increase in the average enrichment of the 
fuel bundle. The environmental impacts of the fuel cycle and of 
transportation of fuel and wastes are described in Table S-3 and S-4 of 
10 CFR 51.51 and 10 CFR 51.52, respectively. Table S-3 of 10 CR 51.51 
and S-4 of 10 CFR 51.52 were

[[Page 55709]]

adopted by the licensee after DAEC received its operating license. 
Consequently, the DAEC FES does not contain a uranium fuel cycle 
environmental analysis similar to Table S-3. The impacts of 
transportation are addressed in the Environmental Report and the FES, 
although the conclusions are not presented in the format of Table S-4. 
An NRC assessment (53 FR 30355, dated August 11, 1988, as corrected by 
53 FR 32322, dated August 24, 1988) evaluated the applicability of 
Table S-3 and S-4 to higher burnup cycles and concluded that there is 
no significant change in environmental impacts for fuel cycles with 
uranium enrichments up to 5 weight-percent U-235 and burnups less than 
60 gigawatt-day per metric ton of uranium (GWd/MTU) from the parameters 
evaluated in Tables S-3 and S-4. Because the fuel enrichment for the 
EPU would not exceed 5 weight-percent U-235 and the rod average 
discharge exposure would not exceed 60 GWd/MTU, the environmental 
impacts of the proposed EPU would remain bounded by these conclusions 
and would not be significant.

Summary

    The proposed EPU would not significantly increase the probability 
or consequences of an accident, would not introduce any new 
radiological release pathways, would not result in a significant 
increase in occupational or public radiation exposures, and would not 
result in significant additional fuel cycle environmental impacts. 
Accordingly, the NRC concludes that no significant radiological 
environmental impacts are associated with the proposed action. Table 2 
summarizes the radiological environmental impacts of the proposed EPU.

 Table 2.--Summary of Radiological Environmental Impacts of EPU at DAEC
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Radiological Waste Stream Impacts:
    Gaseous Waste.................  An increase in release rate that is
                                     linearly proportional to the power
                                     increase would be expected.
    Liquid Waste..................  No change in DAEC zero liquid
                                     release policy.
    Solid Waste:
        Wet Waste.................  Backwashes would increase to create
                                     approximately 3 cubic meters of
                                     resin per year.
        Dry Waste.................  No significant changes.
        Irradiated Components.....  No significant changes.
Dose Impacts......................  May potentially increase radiation
                                     levels; dose would remain within
                                     permitted levels in-plant and
                                     offsite.
Accident Analysis Impacts.........  No significant increase in the
                                     probability or consequences of an
                                     accident.
Fuel Cycle and Transportation.....  Increase in bundle average
                                     enrichment; impacts would remain
                                     within the conclusions of Table S-3
                                     and Table S-4 of 10 CFR Part 51.
------------------------------------------------------------------------

Alternatives to the Proposed Action

    As an alternative to the proposed action, the staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). 
Denial of the application would result in no change in current 
environmental impacts. The environmental impacts of the proposed action 
and the alternative action are similar.
    As stated previously, the estimated cost of adding this nuclear 
generating capacity is approximately half the cost projected for 
purchasing the power and one-third the cost of producing the power by 
constructing a new combined-cycle, natural-gas-fueled facility. Alliant 
concluded that increasing DAEC's capacity would be the most economical 
option for increasing power supply. Furthermore, unlike fossil fuel 
plants, DAEC does not routinely emit sulfur dioxide, nitrogen oxides, 
carbon dioxide, or other atmospheric pollutants that contribute to 
greenhouse gases or acid rain.

Alternative Use of Resources

    This action does not involve the use of any resources different 
than those previously considered in the FES for DAEC, dated March 1973.

Agencies and Persons Consulted

    In accordance with its stated policy, on August 23, 2001, the NRC 
staff consulted with the Iowa State official, Mr. D. McGhee of the 
Department of Public Health, regarding the environmental impact of the 
proposed action. The State official had no comment.

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 
action.
    For further details with respect to the proposed action, see the 
licensee's application dated November 16, 2000, as supplemented April 
16 (two letters) and 17; May 8 (two letters), 10, 11 (two letters), 22, 
and 29; June 5, 11, 18, 21, and 28; July 11, 19, and 25; and August 1, 
10, 16, and 21; and October 17, 2001, and NMC's ``Supplement to DAEC 
Environmental Report,'' submitted on September 22, 2000. Documents may 
be examined and/or copied for a fee at the NRC's Public Document Room, 
at One White Flint North, 11555 Rockville Pike (first floor), 
Rockville, Maryland. Publicly available records will be accessible 
electronically from the ADAMS Public Library component on the NRC Web 
site, http://www.nrc.gov (the Electronic Reading Room). If you do not 
have access to ADAMS or if there are problems in accessing the 
documents located in ADAMS, contact the NRC Public Document Room 
Reference staff at 1-800-397-4209, or 301-415-2737, or by e-mail at 
[email protected].

    Dated at Rockville, Maryland, this 31st day of October 2001.

    For the Nuclear Regulatory Commission.
William D. Reckley,
Acting Chief, Section 1, Project Directorate III, Division of Licensing 
Project Management, Office of Nuclear Reactor Regulation.
[FR Doc. 01-27716 Filed 11-1-01; 8:45 am]
BILLING CODE 7950-01-P