Philadelphia Electric Co.; Limerick Generating Station, Units 1 and 2; Environmental Assessment and Finding of No Significant Impact

NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-352 and 50-353]

Philadelphia Electric Co.; Limerick Generating Station, Units 1

and 2; Environmental Assessment and Finding of No Significant Impact

The U.S. Nuclear Regulatory Commission (the Commission) is

considering issuance of an amendment to Facility Operating License No.

NPF-85, issued to Philadelphia Electric Company, (the licensee), for

operation of the Limerick Generating Station, Units 1 and 2, located in

Montgomery County, Pennsylvania.

Environmental Assessment

Identification of the Proposed Action

This Environmental Assessment has been prepared to address

potential environmental issues related to the licensee's application of

December 9, 1993, as supplemented July 5, September 9, October 19,

November 19, 1994, January 6, and January 23, 1995, to amend the

Limerick Generating [[Page 8256]] Station (LGS), Units 1 and 2

operating licenses. The proposed amendment would increase the licensed

thermal power level from 3293 Mwt to 3458 Mwt. This request is in

accordance with the generic boiling water reactor (BWR) power uprate

program established by the General Electric Company (GE) and approved

by U.S. Nuclear Regulatory Commission (NRC) staff in a letter of

September 30, 1991.

The proposed action involves NRC issuance of a license amendment to

increase the authorized power level by changing the operating license,

including Appendix A of the license (Technical Specifications). No

change is needed to Appendix B of the license (Environmental Protection

Plan--Non-radiological).

The Need for the Proposed Action

The proposed action is needed to permit an increase in the licensed

core thermal power from 3293 Mwt to 3458 Mwt and provide the licensee

with the flexibility to increase the potential electrical output of

LGS, Units 1 and 2, providing additional electrical power to service

domestic and commercial areas.

Environmental Impacts of the Proposed Action

The ``Final Environmental Statement (FES) Related to Operation of

Limerick Generating Station, Units 1 and 2'' was issued April 1984

(NUREG-0974). The licensee submitted GE Topical Report, NEDC-32225P,

``Power Rerate Safety Analysis Report for Limerick Generating Station,

Units 1 and 2,'' Class III, dated September 1993, as Attachment 3 to

the December 9, 1993 submittal. NEDC-32225P contains the safety

analysis prepared by GE to support this license change request and the

implementation of power uprate at LGS, Units 1 and 2. The analyses and

evaluations supporting these proposed changes were completed using the

guidelines in GE Topical Report NEDC-31897P-A, ``Generic Guidelines for

General Electric Boiling Water Reactor Power Uprate,'' Class 3, dated

May 1992, and NEDC-31948P, ``Generic Evaluations of General Electric

Boiling Water Reactor Power Uprate,'' Class III, dated July 1991. The

NRC reviewed and approved GE Topical Reports NEDC-31897P-A and NEPC-

31948P in a September 30, 1991, letter and in a letter from W. Russell,

NRC, to P. Marriotte, GE, dated July 31, 1992.

The licensee provided information regarding the nonradiological and

radiological environmental effects of the proposed action in the

December 9, 1993 application and supplemental information in the

January 6, and January 23, 1995 submittal. The staff has reviewed the

potential radiological and non-radiological effects of the proposed

action on the environment as described below.

Non-Radiological Environmental Assessment

Power uprate will not change the method of generating electricity

nor the method of handling any influents from nor effluents to the

environment. Therefore, no new or different types of environmental

impacts are expected.

The staff reviewed the nonradiological impact of operation at

uprated power levels on influents from the Perkiomen Creek, Schuylkill

and Delaware Rivers and effluents to the Schuylkill River. LGS, Units 1

and 2 each have a closed-loop circulating water system and cooling

tower for dissipating heat from the main turbine condensers. The

cooling towers are operated in accordance with the requirements of

National Pollution Discharge Elimination System (NPDES) Permit No.

PA0051926. The current permit was renewed on December 12, 1994 and is

effective through December 31, 1999. The only increase in LGS water

intake due to operation at power uprate conditions is due to increased

evaporation in the hyperbolic natural draft cooling towers. In the

January 6, 1995 letter, the licensee indicated that the existing

consumptive flow will conservatively increase from 38,059,065 to

40,723,200 gallons per day (total for both units), depending on

atmospheric conditions. The velocity of the intake water will increase

less than 7 percent. Makeup is drawn from the Schuylkill River,

Perkiomen Creek, or the Delaware River, depending on flow and

temperature. When makeup is drawn from the Delaware River through the

Point Pleasant Pumping Station via the Bradshaw Station, 3 percent

additional evaporative losses must be considered. The increase makeup

flow (including evaporative losses), is within the existing water

diversion consumptive use limit of 42,000,000 gallons per day specified

in the original permitting evaluations.

Makeup water requirements for systems and components other than the

cooling towers are not expected to change due to operation at uprated

power levels. The licensee indicated that the only potential change is

due to increased reactor operating pressure which could slightly

increase leakage through valve packing. System leakage, however, is

processed through the liquid radwaste system and returned to the

condensate storage tank for reuse. Based on the above considerations,

the staff concluded that the effect of makeup requirements at uprated

power levels on the environment is not significant.

The licensee does not expect any increase in the cooling tower

blowdown due to the physical limitation in the blowdown system.

Likewise, the licensee does not expect any increase in the blowdown

discharge velocity. However, the licensee indicated that the blowdown

discharge temperature will increase less than 0.1 deg.F. This

temperature rise will have an insignificant effect on the thermal

plume. This increase is within the NPDES permit limit.

An increase in cooling tower drift is not anticipated for operation

at uprated conditions. Drift is a function of physical geometry, water

flow, and wind conditions, none of which are changed by power uprate.

Therefore, the licensee has indicated that the original evaluation of

impacts to the terrestrial environment is not altered.

The only changes to the cooling tower water chemistry are due to

increased evaporation from the towers. Concentrations of dissolved and

suspended solids in the blowdown will increase approximately less than

7 percent, which is within NPDES permit limits. The licensee stated

that the use of biocides and corrosion inhibitors in the circulating

water system may change as a result of operation at uprated power

levels. However, the licensee stated that change in chemical usage

would not impact existing NPDES permit limitations.

Nonradiological effluent discharges from other systems were also

considered. Nonradiological effluent limits for such systems as yard

drains, sewage treatment plant, and laundry drains are established in

the NPDES permit. Discharges from these systems are not expected to

change significantly, if at all, because operation at uprated power

levels is governed by the limits in the NPDES permit. Thus, the impact

on the environment from these systems as a result of operation at

uprated power levels is not significant.

Operation at uprated power levels will not result in increased

noise generation from the majority of plant equipment. Some of this

equipment, such as the main turbine and generator will operate at the

same speed and thus will not contribute to increased offsite noise.

Other major plant equipment is located within plant structures and will

not lead to increased offsite noise levels. The main station

transformers will operate at an increased kilovolt-ampere level which

will cause an insignificant increase in the overall noise level. The

[[Page 8257]] makeup pumps, which are indoors, will operate at the same

level, however, in some cases cycling on slightly more frequently. The

pumps at the Bradshaw Station are variable speed and, when used, will

operate at a slightly higher speed. The pumps are indoors; therefore,

the outside noise level increase will be insignificant.

The licensee has stated that there are no changes required to the

LGS Environmental Protection Plan as a result of operation at uprated

power levels. Specifically the licensee stated:

Other non-radiological environmental impacts of the proposed

power rerate were reviewed based on the information submitted in the

Environmental Report, Operating License Stage, the NRC Final

Environmental Statement (FES), Operating License Appendix B (i.e.,

Environmental Protection Plan), the requirements of the applicable

NPDES permits, which include the outfall limits, and the Delaware

River Basin Commission Water Use permit. We have concluded the

proposed power rerate will have insignificant impacts on the non-

radiological elements of concern and the plant will be operated in

an environmentally acceptable manner as established by the FES.

Existing Federal, State and Local regulatory permits presently in

effect will accommodate power rerate without modification.

The FES described the impact of plant operation on fogging in the

vicinity of the facility. The FES discussed that the increase in

fogging due to plant operation was expected to blend in with the

natural fog and be indistinguishable. The staff expects that operation

of the plant at uprated power levels will result in only a minimal

increase in fogging over that discussed in the FES. Thus, the impact of

plant operation on local fogging, including operation at uprated power,

remains insignificant.

Radiological Environmental Assessment

The licensee evaluated the impact of the proposed amendment to show

that the applicable regulatory acceptance criteria continue to be

satisfied for the uprated power conditions. In conducting this

evaluation, the licensee considered the effect of the higher power

level on source terms, onsite and offsite doses, and control room

habitability during both normal operation and accident conditions. The

licensee provided information regarding the radiological environmental

effects of the proposed action in NEDC-32225P and supplemental

information in the January 6, 1995 submittal. In Sections 8.1 and 8.2

of NEDC-32225P, the licensee discussed the potential effect of power

rerate on liquid and gaseous radioactive waste systems. Sections 8.3

and 8.4 discussed the potential effect of power uprate on radiation

sources in the reactor coolant resulted from coolant activation

products, activated corrosion products and fission products. Section

8.5 of the Topical Report discussed the radiation levels during normal

operation, normal post-operation, post-accident, and offsite doses

during normal operation. Finally, Section 9.2 of NEDC-32225P presented

the results of calculated whole body and thyroid doses at the uprated

power and current authorized power conditions at the exclusion area

boundary and the low population zone that might result from the

postulated design basis radiological accidents [i.e., loss-of-coolant-

accident (LOCA), main steam line break accident (MSLBA) outside

containment, fuel handling accident (FHA) and control rod drop accident

(CRDA)].

In Section 8.1 of NEDC-32225P, the licensee stated that there will

be only a slight increase in the liquid radwaste collection as a result

of operation at higher power levels. The liquid waste system collects,

monitors, processes, stores, and returns processed radioactive waste to

the plant for reuse or for discharge. The largest contributor to the

liquid waste results from the backwash of the condensate demineralizers

and deepbeds. The rate of loading on the demineralizers increases,

resulting in the average time between backwash precoat being reduced

slightly; this reduction does not affect plant safety. Similarly, the

reactor water cleanup (RWCU) filter/demineralizers will require

slightly more frequent backwashes due to slightly higher levels of

activation and fission products. The power uprate will increase the

flow rate through the condensate demineralizers, with a subsequent

reduction in the average time between backwashing. Additionally,

neither the floor drain collector subsystem nor the waste collector

subsystem is expected to experience a significant increase in the total

volume of liquid waste due to operation at the uprated level.

The licensee stated that while the activated corrosion products in

liquid wastes are expected to increase proportionally to the square of

the power increase, the total volume of processed waste is not expected

to increase appreciably. Based on its analyses of the liquid radwaste

system, the licensee has concluded the requirements of 10 CFR part 20

and 10 CFR part 50, appendix I, will be met. Based on the above

considerations, the staff concluded that the power uprate will have no

significant adverse effects on liquid effluents.

The gaseous waste management systems collect, control, process,

store and dispose of gaseous radioactive waste generated during normal

operation and abnormal operational occurrences. These systems include

the standby gas treatment system (SGTS), off-gas recombiner system, the

ambient temperature charcoal treatment system, and various building

ventilation systems. Various devices and processes, such as radiation

monitors, filters, isolation dampers, and fans, are used to control

airborne radioactive gases. The licensee states that the activity of

airborne effluents released through building vents is not expected to

increase significantly with power uprate and the systems are designed

to meet the requirements of 10 CFR part 20 and 10 CFR part 50, appendix

I.

In its power uprate submittal, the licensee has stated that the

greatest contributor of radioactive gases is the noncondensible

radioactive gases from the main condenser, including activation gases

(principally N-16, O-19, and N-13) and radioactive noble gas parents.

The increase in production of these gases is expected to be

approximately proportional to the core power increase. These

noncondensible radioactive gases, along with nonradioactive air due to

inleakage to the condenser, are continuously removed from the main

condensers by the stream jet air ejectors (SJAE). The SJAEs discharge

into the offgas system. The flow of these gases into the offgas system

is included with the flow of H2 and 02 to the recombiner,

which will also increase linearly with core power. Radioactive gases

and H2 and 02 pass from the recombiner through a holdup pipe,

cooler condenser, adsorber bed, and high-efficiency particulate air

(HEPA) filters and exit the facility through the north stack. Gaseous

activity effluent release rates are monitored down stream of the

adsorber bed and alarms are provided in the control room. The licensee

has stated that the operational increases in hydrogen, oxygen, and

noble gases due to uprate are not significant when compared to the

current total system flow which also includes air from condenser

inleakage and steam flows from the air ejector.

The design basis for the offgas system is for activity release

rates of 100,000 microcuries per second based on a mixture of

activation and fission product gases and fuel leakage and a 30-minute

holdup time. The system is designed to meet the requirements of 10 CFR

part 20 and 10 CFR part 50, appendix I. Performance of the system at

uprated power levels is expected to remain within the system design

basis and, thus, to continue to meet the [[Page 8258]] requirements of

10 CFR part 20 and 10 CFR part 50, appendix I.

The contribution of gases to the gaseous waste management system

from building ventilation system is not expected to increase

significantly with power uprate because (1) the amount of fission

products released into the reactor coolant depends on the number of

nature of the fuel rod defects and is not dependent on reactor power,

and (2) the concentration of coolant activation products is expected to

remain unchanged since the linear increase in the production of these

products will be offset by the linear increase in steaming rate.

Based on its review of the gaseous waste management system, the

staff concluded that there will not be a significant adverse effect on

airborne effluents as a result of the power rerate.

The licensee has evaluated the effects of the power uprate on in-

plant radiation levels in the LGS facility during normal and abnormal

operation as well as from postulated accident conditions. The licensee

has concluded that radiation levels from both normal and accident

conditions may increase slightly. However, because many areas of the

plant were designed for higher than expected radiation sources, the

small increase in radiation levels expected due to power uprate will

not affect radiation zoning or shielding in the plant.

During periods of normal and post-operation conditions, individual

worker exposures will be maintained within acceptable limits by the

existing, as low as is reasonably achievable (ALARA) program, which

controls access to radiation areas. Procedure controls compensate for

slightly increased radiation levels.

The offsite doses associated with normal operation are not

significantly affected by operation at the uprated power level, and are

expected to remain below the limits of 10 CFR part 20 and 10 CFR part

50, appendix I.

The main control room (MCR) habitability was evaluated. Post-

accident MCR and technical support center doses were confirmed by the

licensee to be within the limits of General Design Criterion (GDC) 19

or 10 CFR part 50, appendix A.

The increase in LOCA radiological consequences due to power uprate

was analyzed by the licensees. The resultant offsite doses were found

to be within guidelines of 10 CFR part 100. The events evaluated for

uprate were the LOCA, the MSLBA, the FHA, and the CRDA. The whole body

and thyroid doses were calculated for the exclusion area boundary

(EAB), low population zone (LPZ), and the control room. The plant-

specific results for power uprate remain well below established

regulatory limits. The doses resulting from the accidents analyzed are

compared below with the applicable dose limits.

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

LOCA radiological

consequences

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

UFSAR

Location dose Dose Limit

(rem) (rem) @

@3458 3527

MWt MWt\1\

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

Exclusion area:

Whole body dose......................... 0.67 0.68 25

Thyroid dose............................ 0.15 0.15 300

Low population zone:

Whole body dose......................... 1.7 1.7 25

Thyroid dose............................ 0.04 0.04 300

Main control room:

Whole body dose......................... 4.6 4.7 5

Thyroid dose............................ 14.0 14.3 30

Beta.................................... 7.6 7.8 30

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

FHA Radiological Consequences

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

Exclusion area:

Whole body dose......................... 0.7 0.7 6

Thyroid dose............................ 0.95 0.98 75

Low population zone:

Whole body dose......................... 0.099 0.102 6

Thyroid dose............................ 0.13 0.135 75

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

CRDA Radiological Consequences

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

Exclusion area:

Whole body dose......................... 0.04 0.042 6

Thyroid dose............................ 0.32 0.3 75

Low population zone:

Whole body dose......................... 0.014 0.0148 6

Thyroid dose............................ 0.62 0.63 75

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

\1\This number represents 102% of the power uprate level. Doses based on

102% are consistent with Regulatory Guide 1.49, Revision 1 guidance

and are provided to allow for possible instrument errors in

determining the power level.

Based on a review of the licensee's major assumptions and

methodology used in their reconstituted dose calculations and the

staff's original safety evaluation, the staff concluded that the

offsite radiological consequences and control room operator doses at

uprated power levels still remain below 10 CFR part 100 dose reference

values and GDC 19 dose limits. Therefore, the staff concludes that no

significant adverse effect on radiation levels will result onsite or

offsite from the planned power uprate.

It is expected that the increased energy requirements associated

with operation at uprated power will require an increase in the reload

fuel enrichment and will result in increased burnup. The NRC previously

evaluated the environmental impacts associated with burnup values of up

to 60,000 MWd/MT with fuel enrichments up to 5 percent 235U

(published in the Federal Register, 53 FR 6040 dated February 29,

1988). The staff concluded that the environmental impacts associated

with Table S-3 of 10 CFR 51.51, Uranium Fuel Cycle Environmental Data,

and Table S-4 of 10 CFR 51.52, Environmental Impact of Transportation

of Fuel and Waste, are conservative and bound the corresponding impacts

for burnup levels of up to 60,000 MWd/MtU and 235U enrichments up

to 5 percent by weight. In the January 23, 1995 submittal, the licensee

indicated that while fuel burnup and enrichment levels may increase as

a result of operation at uprated power, the burnup and enrichment will

remain within the 5 percent enrichment and 60,000 MWd/MT value

previously evaluated by the staff. Based on the above cited

environmental assessment and the licensee's statements regarding

expected burnup and enrichment values, the staff concludes that the

environmental effects of increased fuel cycle and transportation

activity as a result of operation at uprated power levels are not

significant. [[Page 8259]]

The Commission has completed its evaluation of the proposed action

and concludes that the NRC's FES is valid for operation at the proposed

uprated power conditions for LGS, Units 1 and 2. The staff also

concluded that the plant operating parameters impacted by the proposed

uprate would remain within the bounding conditions on which the

conclusions of the FES are based.

The change will not increase the probability or consequences of

accidents, no changes are being made in the types of any effluents that

may be released offsite, and there is no significant increase in the

allowable individual or cumulative occupational radiation exposure.

The NRC staff finds the radiological and nonradiological

environmental impacts associated with the proposed small increase in

power are very small and do not change the conclusion in the FES that

the operation of LGS, Units 1 and 2, would cause no significant adverse

impact upon the quality of the human environment.

Accordingly, the Commission concludes that there are no significant

radiological environmental impacts associated with the proposed action.

Alternatives to the Proposed Action

Since the Commission has concluded there is no measurable

environmental impact associated with the proposed action, any

alternatives with equal or greater environmental impact need not be

evaluated.

The principal alternative to the action would be to deny the

request. Such action would not significantly reduce the environmental

impact of plant operation but would restrict operation of LGS, Units 1

and 2 to the currently licensed power level and prevent the facility

from generating approximately 60 MWe (165 MWt) additional that is

obtainable from the existing plant design.

Alternative Use of Resources

This action does not involve the use of any resources not

previously considered in the ``Final Environmental Statement related to

the operation of Limerick Generating Station, Units 1 and 2,'' dated

April 1984.

Agencies and Persons Consulted

In accordance with its stated policy, the staff consulted with the

Bureau of Radiation Protection, Pennsylvania Department of

Environmental Resources, regarding the environmental impact of the

proposed action. The State official had no comments.

Finding of No Significant Impact

Based upon the environmental assessment, the Commission concludes

that the proposed action will not have a significant effect on the

quality of the human environment. Accordingly, the Commission 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 letter dated December 9, 1993, as supplemented by letters

dated July 5, September 9, October 19, and November 19, 1994, and

January 6, and January 23, 1995, which are available for public

inspection at the Commission's Public Document Room, The Gelman

Building, 2120 L Street, NW., Washington, DC, and at the local public

document room located at the Pottstown Public Library, 500 High Street,

Pottstown, PA 19464.

Dated at Rockville, Maryland, this 7th day of February 1995.

For the Nuclear Regulatory Commission.

Chester Poslusny,

Acting Director, Project Directorate I-2, Division of Reactor

Projects--I/II, Office of Nuclear Reactor Regulation.

[FR Doc. 95-3520 Filed 2-10-95; 8:45 am]

BILLING CODE 7590-01-M