ML20207G691

Application for Amend to License DPR-65,changing Expiration Date of OL from 101211 to 150731

ML20207G691
Person / Time
Site:	Millstone
Issue date:	12/22/1986
From:	NORTHEAST NUCLEAR ENERGY CO.
To:
Shared Package
ML20207G646	List: B12368, Forwards Application for Amend to License DPR-65,extending Duration of License to 40 Yrs from Date of Issuance of Ol. Fee Paid ML20207G691 ML20207G728
References
TAC-64245, NUDOCS 8701070376
Download: ML20207G691 (21)

Text

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Docket No. 50-336 B12368 Attachment 1 Millstone Unit No. 2 I

Extension of Facility Operating License Proposed License Change j

8701070376 861222 December,1986 PDR ADOCK 05000336 p PDR _.,

The licensee is required to implement and maintain the administrative controls identified in Section 6 of the NRC's Fire Protection Safety Evaluation on the facility dated September 19, 1978. The administrative controls shall be in effect by December 31,1978.

(4) Physical Protection The licensee shall fully implement and maintain in effect all provisions of the following Commission approved documents, including amendments and changes made pursuant to the authority of 10 CFR 50.54(p). These approved documents consist of information withheld from public disclosure pursuant to 10 CFR 73.21:

(a) " Millstone Nuclear Power Station Unit Nos. I and 2 Physical Security Plan", dated June 16, 1978 as revised August 4,1979 and February 20,1979.

(b) " Millstone Nuclear Power Station Suitability, Tmining and Qualification Plan" dated March 31,1981 as revised by pages dated May 28,1981. The plan shall be fully implemented in accordance with 10 CFR 73.55(b)(4) within 60 days of this approval by the Commission. All security personnel shall be qualified within two years of this approval.

(c) " Millstone Nuclear Power Station Unit Nos. I and 2 Safeguards Contingency Plan" submitted Ly letter dated June 2, 1982. The plan shall be fully implemented within 30 days of this approval by the Commission in accordance with 10 CFR 73.40(b).

D. This amended license is effective as of its date of issuance and shall expire at midnight, July 31,2015.

FOR THE NUCLEAR REGULATORY COMMISSION Roger S. Boyd, Acting Director i Division of Reactor Licensing Office of Nuclear Reactor Regulation Original Signed by Roger S. Boyd

Enclosures:

1. Incomplete Preoperational Test Items Which Must Be Completed

2. Change No. 4 to Technical Specifications Contained in Appendix A to DPR-65 Date of Issuance: September 26,1975

Docket No. 50-336 B12368 Attachment 2 Millstone Unit No. 2 Extension of Facility Operating License Safety Evaluation and Environmental Assessment December,1986

MILLSTONE UNIT NO. 2 EXTENSION OF FACILITY OPERATING LICENSE SAFETY EVALUATION AND ENVIRONMENTAL ASSESSMENT I. INTRODUCTION The Northeast Nuclear Energy Company (NNECO) proposes to amend the operating license for the Millstone Unit No. 2 Plant. The proposed amendment would change the expiration date for Operating License DPR-65 from December 11,2010 to July 31,2015.

Section 103(c) c,f the Atomic Energy Act of 1954 provides that a license is to be issued for a specified period not to exceed forty (40) years. The Commission's regulations (10 CFR 50.51) provide that each license will be issued for a fixed period of time not to exceed 40 years from the date of issuance. The current expiration date of the Millstone Unit No. 2 operating license is 40 years from the date of issuance of the construction permit for the facility, December 11, 1970. In accordance with Section 103(c) of the Atomic Energy Act, and Section 50.51 of the Commission's regulations, NNECO proposes to amend the expiration date of the operating license for Millstone Unit No. 2 so as to measure the 40-year period from the date of issuance of that license, i.e.. to July 31,2015. This represents an extension of 4 years,7 months and 20 days.

Set forth below are the results of a comprehensive review of potential safety implications related to plant design and environmental impacts associated with this proposed extension. As demonstrated below, extending the period of operation presents no safety issues or environmental impacts which significantly impact the Millstone Unit No. 2 safety analyses or environmental reviews.

!!. EVALUATION OF POTENTIAL SAFETY IMPACTS NNECO reviewed the safety analyscs set forth in both the Final Safety Analysis Report (FSAR), Facility Technical Specifications and the Commission's Safety Evaluation Report (SER), as supplemented, for Millstone Unit No. 2. This review indicated that, in some areas, prior safety evaluations may potentially be affected by the period of facility operation. Accordingly, additional assessments were completed to confirm that original design and operational considerations encompassed the proposed extended period of operation. As discussed herein, structures, systems and components either are designed and maintained to perform at least tor the full 40-year term, or are subject to detailed inspection, surveillance and maintenance requirements which provide assurance that abnormal degradation will be detected and corrective action taken. Only the reactor pressure vessel (RPV) is considered an essentially non-replaceable plant component. As discussed below, NNECO has determined that the RPV will maintain its functional capabilities at least for the full 40-year operating term herein requested.

, A. Plant Design

1. Electrical Equipment

! NNECO has established extensive programs to identify electrical equipment requiring environmental qualification in accordance with 10 CFR 50.49. Pro 6 rams are in place to assure that environmentally qualified equipment is maintained in a qualified state at all times during plant operation, irrespective of the period of operation. These programs include aging analyses to determine qualified life, scheduled replacements at end of qualified life, maintenance designed to preserve qualification, surveillance performed pursuant to Technical Specifications and i plant procedures, and qualification of affected portions of plant modifications. These programs provide assurance that electrical equipment subject to environmental qualification requirements i will remain qualified to fulfill its intended safety functions throughout plant life.

In summary, the _ above-described programs are designed to

! identify, refurbish or replace components subject to aging throughout plant life. These programs provide assurance that such equipment will respond as required it called upon to mitigate design basis events, regardless of the term of the

, license.

2. Mechanical Equipment 3

a. Inservice Inspection and Testing Mechanical equipment at Millstone Unit No. 2 is subject to the inservice inspection (ISI) requirements established for the American Society of Mechanical Engineers (ASME) Code Class 1, 2 and 3 components. Inservice testing (IST) of ASME Code Class 1,2 and 3 pumps and valves is performed in accordance with ASME Section XI and applicable addenda as required by 10 CFR 50.55a(g), except where written relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i) (Section 3/4.0 of the Millstone Unit No. 2 Technical Specifications). The specific " Limiting Conditions for Operation and Surveillance (ISI and IST)

Requirements" are contained in the Unit No. 2 Technical Specifications, Sections 3/4.1 through 3/4.10. These i

provisions provide assurance that mechanical equipment will be properly maintained throughout the operating life of the plant, regardless of the term thereof. No change to the Millstone Unit No. 2 Technical Specifications in these areas is required to accommodate the requested additional period of operation.

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b. Surveillance and Maintenance Millstone Unit No. 2 Technical Specifications concerning

" Limiting Conditions for Operation and Surveillance Requirements" provide assurance that unexpected degradation of equipment will be detected and corrected regardless of the age of the plant. Failure to satisfy a Limiting Condition for Operation requires specified actions -

to assure that corrective measures are implemented in a timely manner. In addition, surveillance requirements provide for testing, calibration and inspection of those systems or components which are required to assure that operation of the plant will be as prescribed in the Limiting Conditions for Operation. In summary, mechanisms exist which provide assurance that unexpected degradation of plant equipment will be detected and corrected in a timely fashion, throughout the operating life of the plant.

3. Reactor Pressure Vessel The original design of the reactor pressure vessel (RPV) and associated internals considered the effects of 40 years of operation at full power (2700 MW thermal) with a plant capacity factor of 80% (i.e., 32 EFPY). Further, the design >f the RPV meets the intent of 10 CFR 50, Appendix A, GDC 31 " Fracture Prevention of Reactor Coolant Pressure Boundary" (Millstone Unit No. 2 FSAR, Section 1.0, p.l. A-37). Thus, NNECO analyses already approved by the NRC demonstrate the ability of the RPV to operate safely throughout the requested period of operation.

In addition, NNECO has performed analyses that demonstrate that expected neutron fluences over a 40-year service life will not be a limiting consideration. These analyses also demonstrate that the RPV is in compliance with the new final rule on pressurized thermal shock (PTS)(10 CFR 50.61) for at least a 40-year period of operation (see 3. F. Opeka letter to C. I. Grimes, V.S. Noonan, and A. C. Thadani, dated January 23, 1986). In accordance with that rule, NNECO assessed the current and projected Reference Temperrture (RTPTS) values for the RPV.

The current fluence and RTPTS values calculated f .- the RPV and End-of-Life (EOL) do not, and will not, exceed the criteria set forth in 10 CFR 50.61 (2700F for plates, forgings, and axial weld materials or 3000F for circumferential weld materials) as shown in Table 1.

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The evaluation performed with respect to Millstone Unit 2 also confirms that the RPV satisfies 10 CFR Part 50, Appendix G provisions regarding fracture toughness. Finally, NNECO notes that its evaluation demonstrates that the RPV design, based on current operational experience, is consistent with proposed draft guidance (Regulatory Guide 1.99, Revision 2 (draf t)) for end-of-life fluence.

In addition, the Millstone Unit No. 2 RPV surveillance program set forth in Section 3/4.4.9 of the Technical Specifications monitors the radiation-induced changes in the mechanical and impact properties of pressure vessel materials and the cumulative effects of power operation in accordance with 10 CFR Part 50, Appendix H. Changes in the impact properties of the material are evaluated by comparing pre- and post-irradiation Charpy impact test specimens. Changes in mechanical properties are evaluated by a similar comparison from tensile test specimens. Three (3) representative RPV materials are evaluated: base metal; weld metal; and Heat-Affected-Zone (HAZ). Test capsules are removed and tested at intervals throughout the vessel life to provide an indication of the extent of neutron embrittlement on the vessel wall. A complete record of the chemical analysis, fabrication history, and impact and mechanical properties of all surveillance test materials is maintained. The surveillance data is also used to establish new pressure-temperature operating limit curves in accordance with the Technical Specifications.

4. Structures and Systems Millstone Unit No. 2 structures and systems are adequately designed to accommodate a forty year operating life. NNECO has reviewed relevant design documentation, and evaluated applicable surveillance and maintenance procedures to confirm that there is assurance that any potential degradation of functional capabilities of facility structures and systems will be detected in a timely manner, without regard to the period of authorized operation.

a. Structures The original design basis for structures at Millstone Unit No. 2 considered normal operating dead and live loads, as well as accident loads due to design basis accidents and extreme external phenomena such as earthquakes, hurricanes, and floods. The evaluations of abnormal conditions have been and continue to be upgraded as a result of NRC IE Bulletins; i.e., 79-02, 79-14, and 30-11. The original design and reanalysis of structures as part of the IE Bulletins did not consider time as an input to the design

basis. The reason for this is that reinforced concrete and steel building structures that are properly maintained do not degrade significantly with time. All the structures at Millstone Unit No. 2 are well maintained to prevent problems associated with corrosion. In addition, surveillance and maintenance measures provide assurance that any unexpected degradation of - structures will be identified and corrected. Thus, the additional period of operation poses no safety question which has not already been addressed.

Further, the containment structure has a formal inspection program consistent with the provisions of 10 CFR Part 50, Appendix J. The inspection program calls for three integrated leak rate tests (ILRT) in every ten year cycle.

These tests include visual examination of both the interior and exterior surfaces for signs of deterioration which coula affect structural integrity. The containment is also pressurized and leakage is measured to insure the design functions of the containment are maintained. These inspections are well documented and are at closely spaced intervals such that any deterioration affecting structural integrity will be noted and repaired.

Millstone Unit No. 2 has a post tensioned containment, and as such has horizontal, vertical, and dome tendons which are prestressed at the time of construction. To assure that the prestressing force is not reduced over time due to creep, corrosion, and/or deterioration, these tendons are inspected

in accordance with the provisions of Regulatory Guide 1.35 at intervals of one, three, and five years af ter the initial containment structural integrity test, and every five years thereafter. If any indication of deterioration in the tendon system is detected, corrective action will be taken to assure structural integrity.

Settlement of structures during the proposed term of operation was also considered. The majority of structures at Millstone Unit No. 2 are founded on bedrock, with the remaining portions founded on a shallow overburden of stiff soil. These foundation conditions are not susceptible to settlement, and through normal maintenance and surveil-lance any settlement would be reported and monitored to ,

assure no adverse effects to structures or equipment.

Finally, corrosion of structures exposed to the outside environment is also monitored. Certain structures like the vent stack and trash racks on the intake structure are exposed to more harsh ensironments than ordinary buildings.

The vent stack at the Millstone site is shared jointly by Unit Nos.1, 2, and 3. This stack rests on a foundation supported

by piles. Potential corrosion of piles has been addressed in SEP Topic II-4.F for Millstone Unit No. I and found not to be a concern.

b. Systems In addition to the above, NNECO assessed the implications of the additional period of operation on reactor plant systems. As discussed below, the functional capabilities of equipment in reacter plant systems is assured by numerous existing programs.

Adherence to pcriodic maintenance, surveillance, test, and inspection programs assures that reactor plant systems are maintained in a condition of operational readiness regardless of plant age. Any degradation of equipment performance would be detected by these programs. In any event, little or no degradation is anticipated because the increase in license duration does not present an increase in original plant design life of 40 years (see FSAR Section 4.1).

In = the first instance, Technical Specifications contain limiting conditions for operation and surveillance requirements which are concerned with the prevention of equipment degradation. In accordance with Technical Specifications, all transient or operational cycles for co_mponents designed for a limited number of transients or cycles, are recorded and maintained for the duration of the operating license. These programs include checks of performance and availability related parameters of saiety system equipment, such as performance of inservice testing and in-service inspection (IST/ISI, respectively) pursuant to ASME Code Section XI, performance of periodic surveillance (tests, visual inspections, etc.) for safety related equipment normally in standby, programmed periodic maintenance, and trending of periodic test results.

Continuation of these measures provides assurance that potential fatigue of safety system equipment will be corrected in a timely manner, regardless of the period of operation.

B. No Significant Hazards Considerations The proposed revision also does not constitute a significant hazards I consideration as defined by 10 CFR 50.92. Rather, the proposed revision to the Millstone Unit No. 2 operating license only contemplates an extension to the license expiration date. It does not t

involve any changes in the design or operation of the facility. In particular, the proposed change does not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated because no changes to the design or operation of the unit are involved. Thus, no changes to the facility or operating conditions will be made that could alter postulated scenarios regarding accident initiation or response.

Further, the amendment does not require any changes to safety analyses (although additional evaluation was required to confirm that existing evaluations bound the potential effects of 40-year operatico). Also, no modifications to facility procedures or Technical Specifications are necessary. Finally, existing surveillance, inspection, testing and maintenance practices pro-vide assurance that degradation in plant equipment, structures or components will be identified and corrected as necessary throughout the lifetime of the facility. In summary, the potential effects of the extended period of operation are encom-passed within current design considerations.

2. Create the possibility of a new or different kind of accident from any accident previously evaluated because no changes are necessary to the design or operation of the facility (see discus-sion in item 1).

3. Involve a significant reduction in a margin of safety because no changes to the design and operation of the facility and no changes to existing safety analyses are necessary. Further, no revisions to procedures or Technical Specifications are required.

And, as noted, assurance that degradation of equipment, struc-tures or components will be identified and corrected throughout the lifetime of the facility is provided by existing surveillance, inspection, testing and maintenance practices, in summary, the proposed amendment does not constitute a signifi- '

cant hazards consideration because NNECO's evaluation has shown that structures, systems and components at Millstone Unit No. 2 will continue to perform within the limits of existing design and operational criteria throughout the requested additional period of operation. Further, existing measures provide assurance that unexpected degradation of structures, system and components will be detected and timely corrected. Thus, no new safety implications are presented by the requested amendment and existing measures to assure the protection of the public health and safety will continue to provide such assurance during the extended period of operation.

111. ENVIRONMENTAL IMPACTS NNECO reviewed both the Millstone Unit No. 2 Environmental Report, dated June 23, 1972, prepared by NNECO, and the Commission's " Final

Environmental Statement (FES) Related to the Millstone Unit No. 2 Nuclear Power Plant," dated June,1973. As discussed below, the proposed extension of the period of facility operation poses no significant environmental effects that have not already been considered.

A. Radiofonical Impacts

1. General Public

a. Population Estimates in order to assess radiological impacts on the general public as a consequence of the proposed extended period of operation of Millstone Unit No. 2, NNECO reexamined the population estimates on which those figures were based. As discussed below, the original population estimates set forth in the FES significantly overestimated the population growth surrounding _the facility. Consequently, initial estimates regarding the radiological impacts on the general public bound the impacts that would now be predicted using updated population data.

The Millstone Unit No. 2 FES predicted a 22% increase in population within 30 miles of the facility from 1970 to 1980 and a 47% increase from 1970 to 1990. Population data and estimates for the same geographical area (based on 1980 census data) set forth in the Environmental Report for the Millstone Unit No. 3 facility show an actual population increase of 7% from 1970 to 1980 and an estimated population increase of 17 % from 1970 to 1990. The population estimates for Millstone Unit No. 2 were, obviously, highly conservative. The relatively short additional period of operation does not, therefore, give rise to any radiological impacts to the general public that were not already encompassed by those originally predicted and on which the original operating license was predicated.

NNECO also considered the projected population dose. In a report prepared by Northeast Utilities and issued in July, 1981, regarding the low-level radiation health effects for the Haddam Neck and Millstone Nuclear Power Facilities, the estimated 50-mile whole body population exposure was 80 person-rem for an assumed operational life of 40 years for the Millstone Unit No. 2 facility. Review of the effluent reports and calculated whole-body population doses attributable to the combined operation of Millstone Unit Nos. I and 2 for the time period 1979 to the present showed a general decrease in whole-body population exposure compared to the period prior to 1979. This trend is generally attributable to the installation in late 1978 of an off-gas treatment system at Millstone Unit No. I which

resulted in a noticeable decrease in airborne effluent doses.

Combined facility population doses since 1979 have remained essentially steady. Assuming this trend continues, the extension would increase the total whole-body population exposure by 3 person-rems for liquid effluents, and 7 person-rems for airborne effluents. This would increase the total whole-body population exposure to 90 person-rems over forty (40) years. This increase is insignificant compared to the total population dose attributable to natural background and medical use exposures of 2,823,960 person-rems over the period of the extension.(1) The associated annual population doses from radioactive effluents for the site from 1971 to 1984 are given in Table 2.

In summary, as a consequence of both the obvious original conservatism in estimates of population growth and the insignificant impact of plant operation on population exposure in any event, it is apparent that such impacts not only are encompassed by previous evaluations, but would be affected only insignificantly by the extended period of operation.

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[ b. Dose Consequences From Effluents l

Appendix 1 Dose Limits: Since the improvements to the liquid radwaste treatment system in 1976 and the Millstone Unit No. I off gas system in 1978, annual maximum offsite individual doses from the site have been well below 10 CFR 50, Appendix I limits. Maximum individual doses are summarized in Table 3. Thus, simply maintaining current practices in this area provides assurance that continued. operation beyond the currently authorized period of operation will maintain effluent pathway doses well below Appendix Ilimits.

(1) From the report entitled, " Low Level Radiation Health Effects Study for the Haddam Neck and Millstone Power Facilities" (July 1981), NNECO determined that 6,060,000 person-rem whole-body exposure is attributable to average natural background and medical-use radiation for 10 years of available data. Therefore, for the period of the extension, the total population person-rem is calculated by the ratio:

4.66 years = X person-rems X = 2,823,960 person-rem 10 years 6,060,000 person-rems

NNECO also trended the radiological impacts on the environment since operation began. Offsite dose consequences of the station's radioactive liquid and airborne effluents were reviewed for the years spanning 1971 to 1984. The maximum dose rates per year from the site to the whole body and to the thyroid were no greater than 0.55 and 4.7 mrems,(2) respectively (Table 3). This trend, which may reasonably be assumed to continue, and in any event is not affected by the proposed extension, indicates that the dose contribution from liquid or airborne effluents will remain insignificant compared to the natural background annual dose of 125 mrems. Further, the annual direct radiation doses with respect to Millstone Unit No. 2, attributable to the Refueling Water Storage Tank and from transportation of irradiated fuel and solid waste would not differ from those predicted in the FES and would remain insignificant compared to the natural background annual dose of 125 mrem / year.(3) Exposures associated with the transportation of irradiated fuel, and solid radioactive waste, to the general public are given in Table 4.

NNECO also evaluated potential radiological effects (i.e.,

dose rates per year) on speci other than man. These doses were originally projected in the Environmental Report (FES Section 5.5.2) based on generic bicaccumulation and dose conversion factors. Actual data since obtained (reflected in the Annual Radiological Environmental Monitoring Reports for the years 1979-1984) from operational sampling of fish, lobsters, oysters, scallops, mussels and aquatic flora show no increase in bioaccumulation trends in the samples of any plant or site-related radionuclides. Based on this actual operational data obtained from environmental monitormg, no significant radiological impacts are projected to occur over the approximately 30 years of remaining plant life.

(2) These doses represent the effluents from the site post-installation of the Millstone Unit No. I augmented radwaste system. Prior to installation of the new radwaste system, maximum doses were 38 mrems and 75 mrems to the whole body and thyroid, respectively. These doses were not used as they do not reflect the current trend of effluents from the site.

(3) The transportation of irradiated fuel has not occurred recently and is not anticipated to occur in the near future. The retention of irradiated fuel on site for longer periods than originally contemplated allows for significantly greater decay times than first predicted and, thus, lower direct dose contributions than first predicted.

Finally, NNECO evaluated the potential of an environmental buildup of long half-life radionuclides such as Sr-90 and Cs-137. Regular soil sampling was initiated for the Millstone Power Station in 1973. Analysis of samples was initiated in May 1974. These samples show varying levels of Sr-90 and Cs-137 which are attributable to nuclear weapons testing.

No plant-related activity has been detected and no buildup of radionuclides in the soil has been detected which could be attributed to plant operation. NNECO has utilized th.

GASPAR code since 1975 to calculate dose contributions via soll pathways from the dyosition of airborne effluents.

Results of those calculations show zero to minimal dose contributions from long-lived radionuclides. In summary, the requested extension will noc give rise to any additional contribution to dose consequences from an assumed buildup of long-lived radionuclides.

Part 100 Siting Criteria: NNECO also assessed the impact of extended operation on dose estimates from postulated accidents, routine releases and other occurrences to assure continued satisfaction of 10 CFR Part 100 limits during the additional years of operation.

First, the requested 40-year plant operating life is consistent with the period during which postulated plant and transportation accidents were originally considered in Chapter 7 of the FES. Further, the requested extension does not alter the nature of the postulated accidents originally considered. Thus, the radiologicalimpacts of such l accidents will not be affected by the extension. In l particular, NNECO notes that 10 CFR Part 100 requires that maximum individual doses resulting from a postulated fission product release be limited to 25 rems /2 hours for the whole body (WB) and 300 rems /2 hours to the thyroid at the exclusion area boundary, and 25 rem WB and 300 rem l thyroid for the duration of release at the low population zone (LPZ) boundary. The worst case postulated accident for Millstone Unit No. 2 is the Loss of Coolant Accident.

The individual doses for that accident were calculated to be 3.8 rems WB and 151 rems to the thyroid at the site I

boundary and 8.4 rems WB and 56.3 rems to the thyroid at the LPZ. The assumptions made in these determinations are unaffected by the requested exemption. Thus, the postulated dose consequences during the period of the requested extension would be the same as reported above.

With respect to routine releases, data regarding routine releases accumulated since 1971, and through 1984 for the site show a maximum individual total dose from airborne and liquid effluents of 100 mrem whole body and 200 mrem thyroid. Conservatively assuming future exposures will

i duplicate those of the past few years, the resulting dose for the license extension period is approximately 27 mrem WB (6 mrem / year) and 23 mrem thyroid (5 mrem / year) for operation of both Unit Nos. I and 2. Assuming future releases duplicate those of the past, doses will remain well l below Part 100 limits. Further, NNECO's radiological i monitoring program for the Millstone site provides further assurance that the such exposures will remain well below Part 100 limits.(4)

Finally, NNECO assessed the potential impacts of unplanned  ;

releases from the Millstone Station during the period of the l extension. Historically, unplanned releases from December 1975 to December 1984, have resulted in a total maximum individual whole body dose of 1.2 mrem and 1.6 E-3 mrem to the thyroid. Assuming the dose history of unplanned releases remains the same, the doses attributable to unplanned releases during the extension period would be a total individual whole body dose of approximately 0.62 mrem. Thus, based on current available data premised on actual operation,10 CFR Part 100 dose limits will continae to be satisfied during the period of the extension.

2. Occupational Exposure NNECO also evaluated the impact of the proposed extension on predicted radiological occupational exposures, on individual worker as low as reasonably achievable (ALARA) measures, and 10 CFR Part 20 dose limits. Tables 7 and 8 (attached) provide data regarding occupational exposures,

a. ALARA Considerations In 1978, NNECO instituted an ALARA program at Millstone Unit No. 2 which includes a number of significant measures intended to minimize occupational exposures consistent with ALARA considerations. These measures include system decontaminations (g PWR Steam Generators), mockup training, remote tooling and inspection techniques, extensive use (4) NNECO conducts an extensive environmental monitoring program to track the impact of radiological effluents in the environment surrounding the Millstone site attributable to Millstone operations. This program will remain in place during the period of the proposed extension. The only impact associated with the program itself is the man hours required to keep it operational for the license extension period. However, the program will be kept operational during the extension period in any event because it coincides with the period of operation of Millstone Unit No. 3, for which the program is also conducted. The current sampling locations, types, frequencies and required analyses are given in Tables 5 and 6.

of shielding, and special tooling. All of these measures will continue to the end of plant life, including the proposed extension. These measures provide assurance, therefore, that occupational exposures will satisfy ALARA considerations throughout the period of operation. Further, potential improvements in ALARA measures will provide additional assurance in that regard. For example, full system decontamina-tions, including fuel, may become feasible, advanced robotic techniques may be developed, and improved chemistry controls should both lower dose rates and minimize the need for repairs.

Table 7 provides the annual occupational manrem from plant startup through 1985. Table 8 provides a breakdown of exposure by plant systems for the years 1980 through 1984 for Millstone Unit No. 2. NNECO expects that manrem/ year levels will decrease with time. Northeast Utilities is actively seeking methods to reduce total person-rem exposures. As discussed above, more extensive use of system decontaminations, plus improved primary side chemistry controls (such as constant, high ph at PWRs) should lower primary side dose rates. Also, improved secondary side chemistry should reduce steam generator maintenance at PWRs. Advanced ALARA techniques such as obotics should minimize worker time in radiation areas.

Finally, NNECO recognizes that additional occupational exposures will result from decommissioning. However, decommissioning is a one time dose commitment that will be incurred with or without the extension. Indeed, any increase in corrosion product buildup during the period of the extension, will be compensated for by improved chemistry controls and other ALARA measures to actually lower primary side dose rates with time. The inventory of activation products and the resultant radioactivity in the reactor vessel and internals will not increase significantly in the period of extended operation (per NUREG/CR-0310, Volume 1, Chapter 7). Consequently, the extended operating time should have no measurable adverse effect on decommissioning dose requirements.

b. Personnel Dose Limits The above-described ALARA measures provide assurance that occupational exposures will satisfy 10 CFR Part 20 limits durirg the additional years of service. Further, assurance that those limits will be satisfied throughout the life of the facility is provided by existing Technical Specifications which require compliance with 10 CFR Part 20. In addition, one of the primary focuses of the existing Health Physics program is to ensure compliance with 10 CFR Part 20. Each of these measures will continue through the end of the license.

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Finally, NNECO notes that since implementation of the ALARA program in 1978 and establishment of administrative limits more restrictive than those in 10 CFR Part 20, no individual has exceeded the administrative limit of 5 rem per year at any Northeast Utilities' nuclear plant. NNECO foresees no dif ficulty in continuing this record throughout the remaining plant life.

B. Uranium Fuel Cycle Based upon current data regarding the length of operational cycles for Millstone Unit No. 2, extending the period of operation by approximately four years would suggest that fuel requirements for three additional refuelings would result from the requested extension (approximately 1.5 million pounds of U33 0 ). However, the proposed extension actually will have a negligible impact on the previously predicted uranium fuel cycle impacts. As discussed below, the total lifetime fuel requirement for Millstone Unit No. 2, even with the license extension, will actually be less than originally predicted.

The change in fuel requirements (estimated at three (3) additional reloads or approximately 1.5 million pounds of U3 0g) resulting from the extended period of operation would have a negligible impact on the previously identified impacts attributable to Millstone Unit No. 2 resulting from the uranium fuel cycle for the following reasons:

o The original estimate of uranium fuel cycle impacts attributable to Millstone Unit No. 2 were based on thirty (30) years of operation, assuming one initial core-load and twenty-nine (29) annual refuelings. Operating cycles of approximately 10 months were assumed. However, past operating history and future projections indicate that the operating cycles of Millstone Unit No. 2 have and will continue to be 13 to 15 months in duration. As such,25 such cycles are currently projected over the present license expiration date of December 2010. An extension of the license expiration date to July 2015 will only add three more cycles of fuel requirements, totaling 28 cycles over the plant lifetime. This is two cycles less than the original assumption.

Consequently, the actual fuel requirements will likely be less than originally assumed and, thes, associated fuel cycle impacts will also be less, o Cancellation of planned construction of numerous reactors since the TMI accident has created a large surplus of uranium available for operating reactors. The uranium fuel cycle impacts originally considered by the NRC are based on the cumulative lifetimes of 30 years for 236 reactors. Currently, there are presently about 100 operating reactors, with a total of approximately 125 reactors projected for operation in the U.S. within the time frame of the Mills e Unit No. 2

license. This is significantly less than the projected 236 reactors. Thus, the overall fuel cycle impacts associated with mining, fabrication and transportation of uranium fuel

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will be much less than originally assumed. At a minimum, the impacts per year of operation at Millstone Unit No. 2 will be no greater than originally assumed.

Accordingly, no new or additional impacts _will arise as a result of extending the period of operation.

C. Nonradiological Impacts Nonradiological impacts associated with the operation of Millstone Unit No. 2 have previously been accounted for in the environmental assessments for the facility. NNECO reexamined the Environmental Report and the Final Environmental Statement for the facility to assess whether such impacts would be significantly affected by the proposed extension. That reexamination disclosed that, overall, nonradiological environmental impacts would not be directly affected by the extension and, in any event, will continue to be offset by the benefits from plant operation which will continue to accrue to the neighboring population, including consumers.

In conjunction -with their review of Millstone Unit No. 2 impacts, NNECO reviewed the Environmental Report for Millstone Unit No. 3.

Included therein were projections of impacts for the Millstone Station beyond the projections made in connection with the Unit No. 2 evaluations. In particular, the Millstone Unit No. 3 environmental report considered the power station as a single entity, and the effects of _ three unit operation were projected for the life of Unit No. 3, which received its 40-year operating license in January 1986, expiring on November 25, 2025. In addition, environmental license conditions set forth in the Unit No. 3 operating license (Appendix B, Environmental Protection Plan) will also address impacts attributable to all three units at the station. Thus, additional measures of protection not contemplated in the original environmental review for Unit No. 2 will apply throughout the period of the requested extension.

In summary, NNECO's review indicated that no significant new environmental impacts or significant changes in those previously identified in the Environmental Report for Unit No. 2 will result from the extended period of operation. In addition, more recent and more extensive information concerning identified environmental impacts resulting from operations at the Millstone Station (including impacts beyond the period of the proposed extension) was presented in the Environmental Report for Unit No. 3 and evaluated by the NRC in an FES issued in April 1984. Thus, known environmental impacts of operations at the Millstone Station beyond the extension requested here have already been assessed.

NNECO sets forth below their assessment of the effect of the proposed extension on nonradiological (land and aquatic) impacts, as well as the benefits attributable to extended operation that will continue to be provided to consumers. It is apparent that balancing these impacts clearly favors extending the period of operation.

1. Economic Benefits NNECO examined the economics of the Millstone Unit No. 2 license extension. NNECO estimates that the approximately four year extension of the operating life for the facility would lower nominal revenue requirements by about $3.3 billion, or about $163 million in present worth terms (to January,1987).

The principal reason for such savings is that the New England region prefers base load capacity as a replacement for Millstone Unit No. 2 upon its retirement. Extending the unit's life would thus delay the timing of such replacement capacity by the length of the extension period. The estimated costs of such an extension are far lower than the costs associated with delaying an equivalent amount of new base load capacity.

Additional economic effects not directly considered in this esti-mate include the desirability of continuing the plant's contribution to the local property tax base and the effect of payroll and other expenditures for goods and services on communities surrounding the existing plant site. Another quantified benefit is the continued use of an existing generating site, deferring the need to site a new facility in a new location.

Further, new transmission-related expenditures associated with a new facility would be avoided during the period of the extension.

Further, current planning assumptions for the costs and operat-ing characteristics of new generation _ facilities, applying long-term projections of nuclear and fossil fuel prices, indicate that the most cost-effective choice for base load generation in the years beyond 2000 include the so-called " clean" coal technologies (e.g., fluidized bed combustion or a coal gasification facility fueling a combined cycle plant). Both nuclear and " clean" coal generation are projected to have substantially similar total costs if built in New England.

Accordingly, NNECO's estimate utilizes " clean" coal generating costs in determining savings associated with the capacity deferral. Costs attributed to the Millstone Unit No. 2 license extension include all operating and maintenance expenses (including fuel), as well as an assumed amount of necessary capital expenditures made for the unit. The estimate assumes identical system fuel savings associated with the displacement of relatively high cost oil-fired generation, whether by extending Millstone Unit No. 2's operating life or by the

j. .-

i operation of its replacement. The principal cost elements of

.the estimate are tabulated in Table 9. Dollar amounts are in millions; numbers in parentheses are negative, denoting a _

lowering of revenue requirements (i.e., a benefit). The principal eccnomic assumptions of the. cost analysis'- are presented in Table 10. Obviously, substantial cost savings will be' realized for the Millstone Unit No. 2 sponsors' consumers by displacing existing or other potential generation resources by extending Millstone Unit No. 2 operation,

p. 2. Land Use The use of the Millstone site was considered in the FES .for Millstone Unit Nos. I and 2. The total area of land dedicated to the operation' of.the two units remains the same as originally contemplated (approximately 22 acres), although the

proportions used for parking, temporary storage, construction, permanent buildings, and fill areas have changed. In' addition, the 375 acres of the Millstone site lef t in a natural state or g

available for public use in 1973 has been reduced to 250 acres because of the construction of Millstone Unit No. 3 and other permanent buildings onsite, with associated parking-lots and landscaping. However, such impacts would have been assessed, 4

as appropriate, in conjunction with the. Unit No. 3 license review. In any event, the proposed extension does not create l

new or alter previously established land uses. Thus, no new land use impacts result from the proposed extension.

I r 3. Aquatic Impacts i

No significant aquatic impacts have been observed as a result of thermal or chemical discharges attributable to Millstone Unit No. 2 or from the withdrawal of- cooling water. In 4 addition, study methodologies have changed over the years to provide improved sampling programs (some having been ongoirig L for as long as fifteen (15) years) in order to better quantify

!~ aquatic impacts from operations at the Millstone Station. The results of many of these programs were considered in the Environmental Report for Unit No. 3. Again, however, there is

• j_ no evidence of significant aquatic impacts esulting from i operations at the Millstone Station.

l? Finally, the Connecticut Department of Environmental

! Protection administers the National Pollistant Discharge l Elimination System (NPDES) permit now in effect for the Millstone Nuclear Power Station and has set conditions and f limits expressly designed to protect indigenous fish, shellfish, and wildlife. The proposed extension will not alter those

! conditions and limits.

!I D.- Environmental Assessment The above information demonstrates that there are no significant adverse impacts on the quality of the human environment which result from the proposed extension. Although some additional impacts will occur as a result of normal plant operations, none of these effects are significant. For example, additional radioactive releases associated with normal operation obviously will occur.

liowever, the proposed extension does not alter the fact that such releases are negligible compared to natural background regardless of the period of operation. In addition, any adverse impacts have previously been found and continue to be outweighed by the benefits attributable to extending operation.

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