Georgia Power Company, Oglethorpe Power Corporation, Edwin I. Hatch Nuclear Plant, Units 1 and 2; Environmental Assessment and Finding of No Significant Impact

NUCLEAR REGULATORY COMMISSION

[Docket Nos. 50-321 and 50-366]

Georgia Power Company, Oglethorpe Power Corporation, Edwin I.

Hatch Nuclear Plant, Units 1 and 2; Environmental Assessment and

Finding of No Significant Impact

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

considering issuance of amendments to Facility Operating License Nos.

DPR-57 and NPF-5 issued to Georgia Power Company, et al. (GPC or the

licensee), for operation of the Edwin I. Hatch Nuclear Plant, Units 1

and 2, located in Appling County, Georgia.

Environmental Assessment

Identification of the Proposed Action

This Environmental Assessment, provided by the licensee, addresses

potential environmental issues related to GPC's application to amend

Plant Hatch, Units 1 and 2, Operating Licenses. The proposed amendments

would increase the licensed core thermal power from 2436 MWt to 2558

MWt, which represents an increase of 5 percent over the current

licensed power level. 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 the NRC staff in a letter

from W.T. Russell, NRC, to P.W. Marriott, GE, dated September 30, 1991.

Implementation of the proposed power uprate at Plant Hatch will result

in an increase of steam flow to approximately 106 percent of the

current value, but will not require changes to the basic fuel design.

Core reload design and fuel parameters will be modified as power uprate

is implemented to support the current 18-month reload cycle. The higher

power level will be achieved by expanding the power/flow map and

slightly increasing reactor vessel dome pressure. The maximum core flow

limit will not be increased over the pre-uprate value. Implementation

of this proposed power uprate will require minor modifications, such as

resetting of the safety relief setpoints, as well as calibrating plant

instrumentation to reflect the uprated power. Plant operating,

emergency, and other procedure changes will be made where necessary to

support uprated operation.

The proposed action involves NRC issuance of license amendments to

uprate the authorized power level by changing the Operating Licenses,

including Appendix A (Technical Specifications). Appendix B of the

Operating License (Environmental Technical Specifications) does not

require revision as a result of power uprate.

The Need for the Proposed Action

The proposed action would authorize GPC to increase the potential

electrical output of Plant Hatch by approximately 40 megawatts per unit

and thus would provide additional electrical power to service GPC's

grid.

Environmental Impacts of the Proposed Action

The ``Final Environmental Statement'' (FES) related to operation of

Plant Hatch Units 1 and 2 (Reference 6) evaluates the nonradiological

impact of operation at a maximum design reactor power level of 2537 MWt

per unit. By letter dated January 13, 1995 (Reference 1), GPC submitted

the proposed amendment to implement power uprate for Hatch Units 1 and

2 which is the subject of this environmental assessment. Enclosure 2 of

that submittal provided information on the noradiological environmental

aspects of the amendment request. Enclosure 4 was the Plant Hatch power

uprate licensing report (GE report NEDC-32405P) which provided

information on the radiological environmental impact of power uprate.

The proposed amendments allowing power uprate operation will not

have a significant impact on the environment and the change does not

constitute an unreviewed environmental question. The nonradiological

and radiological effects of the proposed action on the environment are

described below.

Nonradiological Environmental Assessment

Power uprate will not change the method of generating electricity

nor the method of handling any influents from the environment or

effluents to the environment. Therefore, no new or different types of

environmental impacts are expected.

The detailed evaluation presented below and in Reference 1

concludes that nonradiological parameters affected by power uprate will

remain within the bounding conditions cited in the FES, which concludes

that no significant environmental impact will result from operation of

Plant Hatch. This conclusion remains valid for power uprate.

The FES evaluated the nonradiological impact at a maximum design

reactor power level of 2537 MWt per unit (approximately 104 percent of

the current licensed power level). The parameters evaluated in the

Environmental Report and the subsequent FES (References 4 through 6)

were re-evaluated at 2558 MWt to determine whether the proposed change

is significant relative to adverse environmental impact. Table E2-1 of

Reference 1 provided a comparison of environmental-related operation

parameters at rated and uprated power. Both units at Plant Hatch

utilize a closed-loop circulating year system and forced air cooling

towers for dissipating heat from the main turbine condenser. Other

equipment is cooled by the plant service water (PSW) and residual heat

removal (RHR) service water systems. The cooling towers and service

water systems are operated in accordance with the requirements of the

National Pollutant Discharge Elimination System (NPDES) Permit No. GA

0004120, which expires October 31, 1997. No notification changes or

other action relative to the NPDES Permit are required.

[[Page 38594]]

The withdrawal of cooling water from the Altamaha River is expected

to increase slightly, primarily due to the increase in the evaporation

rate from the cooling towers. Emergency system flows are expected to

remain generally unchanged. Although increased heat loads are expected

for nonsafety-related loads, such as the main generator stator coolers,

hydrogen coolers, and exciter coolers, heat loads will remain within

the existing design heat loads of the service water systems.

The circulating water system design flow rate is the primary basis

for determining makeup water for the Plant Hatch cooling towers. Other

factors affecting tower makeup are tower performance and meteorological

conditions. Based on the review of cooling tower performance parameters

associated with power uprate, the design flow rate of the cooling

towers will not change. Makeup requirements may increase slightly due

to increased heat load on the towers and the associated increase in

evaporation. As discussed in Enclosure 2 of Reference 1, the increase

in makeup (withdrawal rate is expected to be approximately 5 percent or

500 gpm. This projected increase associated with the uprate is not

significant and is enveloped by the river water withdrawal rates

discussed in the FES and the rates approved under the current Georgia

Surface Water Withdrawal Permit for Plant Hatch. Intake canal velocity

will not be significantly affected. No measurable effects on fish

impingement or plankton entrainment are expected.

Changes in cooling tower blowdown rate and cooling tower chemistry

as a result of the uprate are not significant. Any changes in blowdown

rate and cooling tower cycles of concentration resulting from uprated

power operation are enveloped by the existing design criteria discussed

in FES.

Cooling tower drift does not increase as a result of the uprate

since the circulating water flow rate does not change. Cooling tower

blowdown temperature associated with power uprate operation increase

slightly (<1 deg.F), thereby producing a slight increase in river

discharge temperature. A review of the increase in the river discharge

temperature relative to the conclusions of the FES and thermal studies

required to support licensing of the plant indicates the slight

temperature increase is not significant.

The thermal plume characteristics are not expected to change

significantly as a result of power uprate. Circulating water and

service water flow rates remain unchanged. The discharge temperature to

the cooling towers should increase by no more than 1 deg.F due to

operation at power uprate conditions. The corresponding change in

discharge temperature at the river will not significantly impact the

size or characteristics of the thermal plume. Thermal plume studies

conducted during original licensing and the FES conclusions relative to

thermal impacts remain valid for the uprated condition.

No significant change in discharge flow rate, velocity, or chemical

composition will occur due to the proposed power uprate. Power uprate

does not impact the discharge characteristics upon which the NPDES

Permit is based. No notification, changes, or other actions relative to

the NPDES Permit are required.

No change in the groundwater withdrawal required to supply the

Hatch treatment plant or fire protection system will result from the

proposed uprate.

The evaluation also considered the flow rate required by the liquid

radwaste system (e.g., floor and equipment drains) due to the proposed

uprate. No significant change in liquid radwaste quantities or activity

levels which would increase the required radwaste dilution flow are

expected. Therefore, the impact on the environment from these systems

as a result of operation at the uprate power levels is not significant.

Plant operation at uprated power conditions will not affect current

noise levels. Major plant equipment is housed within structures located

on the plant site and is not a major contributor to surrounding noise

levels. Equipment, such as the main turbines/generators and the cooling

towers, will continue to operate at the current speed and noise level.

The generator step-up transformers will operate at an increased KVA

level; however, the overall noise level will not increase

significantly.

Thus, the proposed uprate will not result in any significant

environmental impact and is not an unreviewed environmental question.

In addition, no actions relative to the Environmental Technical

Specifications (ETS), NPDES permit or other environmental documents are

required.

Radiological Environmental Assessment

Georgia Power Company evaluated the impact of the proposed power

uprate amendment and concluded that the applicable regulatory

acceptance criteria relative to radiological environmental impacts will

continue to be satisfied for the uprated power conditions. Existing

Technical Specifications limits on radiological effluents will be

maintained. In conducting this evaluation, GPC considered the effect of

the higher power level on liquid radioactive wastes, gaseous

radioactive wastes, and radiation levels both in the plant and offsite

during both normal operation and post-accident.

Enclosure 4 of Reference 1 provides the power uprate safety

analyses report for Plant Hatch, as well as an assessment of the

radiological effects of power uprate operation during both normal and

postulated accident conditions. Sections 8.1 and 8.2 discuss the

potential effect of power uprate on the liquid and gaseous radwaste

systems. Sections 8.3, 8.4, and 8.5 discuss the potential effect of

power uprate on radiation sources within the plant and radiation levels

during normal and post-accident conditions. Section 4.4 discusses the

standby gas treatment system (SGTS). Section 9.2 presents the results

of the calculated whole body and thyroid doses at the exclusion area

boundary and the low population zone that might result from the

postulated design basis radiological accidents. All offsite doses

remain below established regulatory limits for power uprate operation.

The floor drain collector subsystem and the waste collector

subsystem both receive inputs from a variety of sources (e.g., leakage

from component cooling water system, reactor coolant system, condensate

and feedwater system, turbine, and plant cooling water system).

However, leakages from these systems are not expected to increase

significantly since the operating pressures of these systems are either

being maintained constant or are being increased only slightly due to

the proposed power uprate.

The largest source of liquid radioactive waste is from the backwash

of the condensate demineralizers. These demineralizers remove activated

corrosion products which are expected to increase proportionally to the

proposed power uprate. However, the total volume of processed waste is

not expected to increase significantly, since the only appreciable

increase in processed waste will be due to the slightly more frequent

cleaning of these demineralizers. Based on a review of plant effluent

reports and the slight increase expected due to the proposed power

uprate, GPC has concluded that the slight increase in the processing of

liquid radioactive wastes will not have a significant increase in

environment impact and that requirements of 10 CFR part 20 and 10 CFR

part 50, Appendix I, will continue to be met.

[[Page 38595]]

Gaseous radioactive effluents are produced during both normal

operation and abnormal operation occurrences. These effluents are

collected, controlled, processed, stored, and disposed of by the

gaseous radioactive waste management systems which include the various

building ventilation systems, the off gas system, and the SGTS. The

concentration of radioactive gaseous effluents released through the

building ventilation systems during normal operation is not expected to

increase significantly due to the proposed power uprate since the

amount of fission products released into the reactor coolant (and

subsequently into the building atmosphere) depends on the number and

nature of fuel rod defects and is not dependent on reactor power level.

The concentration of activation products contained in the reactor

coolant is expected to remain unchanged, since the linear increase in

the production of these activation products will be offset by the

linear increase in steaming rate. Therefore, based on its review of the

various building ventilation systems, GPC has concluded that there will

not be a significant adverse effect on airborne radioactive effluents

as a result of the proposed power uprate.

Radiolysis of the reactor coolant causes the formation of hydrogen

and oxygen, the quantities of which increase linearly with core power.

These additional quantities of hydrogen and oxygen would increase the

flow to the recombiners by 5 percent during uprated power conditions.

However, the operational increases in hydrogen and oxygen remain within

the design capacity of the system.

The SGTS is designed to minimize offsite and control room radiation

dose rates during venting and purging of both the primary and secondary

containment atmospheres under accident or abnormal conditions. This is

accomplished by maintaining the secondary containment at a slightly

negative pressure with respect to the outside atmosphere and

discharging the secondary containment atmosphere through high-

efficiency particulate air (HEPA) filters and charcoal absorbers. The

SGTS charcoal absorbers are designed for a charcoal loading capacity of

2.5 mgI/gC for the 30-day loss-of-coolant accident (LOCA) scenario. The

proposed power uprate will increase the post-LOCA iodine loading by 5

percent; however, the charcoal loading will remain within the 2.5 mgI/

gC design limit. Therefore, there will be no significant increase in

environmental impact.

Georgia Power Company evaluated the effects of the power uprate on

in-plant radiation levels for Plant Hatch during both normal operation

and post-accident. GPC's conclusions are that radiation levels during

both normal operation and post-accident may increase slightly

(approximately proportional to the increase in power level). The slight

increases in in-plant radiation levels expected due to the proposed

power uprate should not affect radiation zoning or shielding

requirements. Individual worker occupational exposures will be

maintained within acceptable limits by the existing as low as

reasonably achievable (ALARA) program which GPC uses to control access

to radiation areas. Therefore, the slightly increased in-plant

radiation levels will not have a significant environmental impact.

The offsite doses associated with normal operation are not

significantly affected by operation at the proposed uprated power level

and are expected to remain well within the limits of 10 CFR part 20 and

10 CFR part 50, Appendix I. Existing Technical Specifications limits

will not be changed due to uprate. Therefore, offsite doses due to

power uprate conditions will not result in a significant environmental

impact.

Georgia Power Company performed does evaluations for design basis

accidents at or above 102% of the uprated power level and reported

these results in Reference 1. The offsite doses remain below regulatory

limits and the increase due to power uprate is 5% or less.

The NRC staff agrees with GPC's assessment of the radiological

effects of 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. As an alternative to the proposed action, the staff

considered denial of the proposed action. Denial of the application

would result in no change in current environmental impacts of plant

operation, but would restrict operation of Plant Hatch to the currently

licensed power level. The environmental impacts of the proposed action

and the alternative action are similar.

Alternative Use of Resources

This action does not involve the use of any resources not

previously considered in the Final Environmental Statement for Plant

Hatch.

Agencies and Persons Consulted

In accordance with its stated policy, on July 20, 1995, the staff

consulted with the Georgia State official, James L. Setser of the

Environmental Protection Division, Department of Natural 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 January 13, 1995, as supplemented by letters

dated April 5 and June 20, 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 Appling County Public Library, 301 City

Hall Drive, Baxley, Georgia.

References

1. Georgia Power Company HL-4724, J. T. Beckham, Jr., to NRC,

``Power Uprate Operation,'' dated January 13, 1995.

2. Georgia Power Company HL-4812, J. T. Beckham, Jr., to NRC,

``Response to Request for Additional Information--Power Uprate

Submittal,'' dated April 5, 1995.

3. Federal Register Vol. 60, No. 41, ``Niagara Mohawk Corporation;

Environmental Assessment and Finding of No Significant Impact,'' dated

March 2, 1995.

4. Georgia Power Company ``Final Environmental Statement for Edwin

I. Hatch Nuclear Plant Units 1 and 2,'' October 1972.

5. Georgia Power Company Edwin I. Hatch Nuclear Plant--Unit 2

Environmental Report, Operating License Stage, June 1975.

6. Georgia Power Company ``NUREG-0417,'' Final Environmental

Statement Related to Operation of Edwin I. Hatch Nuclear Plant Unit No.

2, March 1978.

Dated at Rockville, Maryland, this 21st day of July 1995.

For the Nuclear Regulatory Commission.

Herbert N. Berkow,

Director, Project Directorate II-2, Division of Reactor Projects--I/II,

Office of Nuclear Reactor Regulation.

[FR Doc. 95-18444 Filed 7-26-95; 8:45 am]

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