ML20202J713

Summary of 990107 Meeting with Util Re Info Provided by Util for Severe Accident Mitigation Alternative (SAMA) Review & Site Audit

ML20202J713
Person / Time
Site:	Calvert Cliffs
Issue date:	01/28/1999
From:	Craig C NRC (Affiliation Not Assigned)
To:	Essig T NRC (Affiliation Not Assigned)
References
NUDOCS 9902090224
Download: ML20202J713 (46)

Text

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& UNITED STATES

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! ;5 j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001

\, +/ January 28, 1999 L MEMORANDUM TO: Thomas H. Essig, Acting Chief Generic issues and Environmental Projects Branch Division of Reactor Program Management Office of Nuclear Reactor Regulation FROM: Claudia M. Craig, Senior Project Manage Q, M k ,

Generic issues and Environmental Projects ranch Division of Reactor Program Management C(

v Office of Nuclear Reactor Regulation

SUMMARY

OF MEETING BETWEEN BALTIMORE GAS AND ELECTRIC (BGE) AND THE NUCLEAR REGULATORY COMMISSION (NRC) TO DISCUSS INFORMATION PROVIDED BY BGE FOR THE SEVERE ACCIDENT MITIGATION ALTERNATIVE (SAMA) REVIEW AND SITE AUDIT The NRC staff met with representatives of BGE on January 7,1999, to discuss information provided by BGE in response to the staff request for additional information (RAI) regarding SAMAs. The staff issued the RAI by letter dated September 9,1998, and BGE provided its responses by letter dated December 3,1998. Upon review of the BGE responses, the staff identified areas that needed further clarification or discussion. The staff provided a list of issues to BGE in a teleconference on December 17,1998, in preparation for this meeting. The meeting was intended to be a working level meeting between the NRC reviewers and the BGE staff responsible for the SAMA analysis to further discuss specific issues. Attachment 1 is a list of attendees. Attachment 2 is a' copy of the handouts discussed at the meeting. An advance copy of handouts was sent directly to the Public Document Room or, January 11,1999.

The SAMA review is performed as part of the environmental review performed under the National Environmental Policy Act (NEPA) and the requirements of 10 CFR Part 51. The SAMA methodology identifies the accident sequences that contribute to overall plant risk, identifies mitigative altematives to reduce the frequency of that risk, and evaluates the alternatives using a cost benefit analysis.

The following issues were discussed at the meeting: the use of pre-initiator actions; the relationship between Tables 7 and 8 in the RAI response; the use of saved sequences; cost estimates for a number of SAMAs; the possible implementation of SAMA number 66b; Figure 1 in the pal response and whether it addresses core damage frequency (CDF) or containment release or both; how BGE derived the top 10 SAMA list; revised population projections; the

relationship between change in CDF and the averted offsite dose estimates; the BGE best '

estimate rationale and methodology, including the use of adjustment factors, correction factors, (

and the Unit 1 and 2 differences; the BGE SAMA identification process; the evacuation D

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! - assumptions; a breakdown of CDF using initiating events; details of the BGE PRA and possible

! differences between it and other PRAs; and whether the accident management strategies from j l Generic Letter 88-20, Supplement 2 were used in the SAMA evaluation.

l Following the public meeting, the NRC staff reviewed documentation on-site related to the 1 L SAMA review. The staff reviewed the details of individual SAMAs, including BGE spreadsheets and further discussed the details of how BGE calculated the bounding and best estimate l '., benefits, Attachments: As stated Docket Nos. 50-317, 50-318 l

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T. Essig January 28, 1999  ;

assumptions; s breakdown of CDF using initiating events; details of the BGE PRA and possible differences between it and other PRAs; and whether the accident management strategies from Generic Letter 88-20, Supplement 2 were used in the SAMA evaluation.

' Following the public meeting, the NRC staff reviewed documentation on-site related to the '

SAMA review. The staff reviewed the details of individual SAMAs, including BGE spreadsheets  !

and further discussed the details of how BGE calculated the bounding and best estimate benefits. ,

L Attachments: As stated Docket Nos. 50-317,50-318 l' ' ,

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• Except for the attendees list in attachment 1, an advance copy of the handouts to this meeting

!s . were sent directly to the PDR on January 11,1999

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Exhibit 2

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, ATTENTION: DOCUMENT CONTROL DESK i i

PLEASE EXPEDITE PROCESSING OF ATTACHED DOCUMENTS 1

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MEETING ATTENDEES JANUARY 7,199g NAME , +

" ORGANIZATION i

Neil Haggerty . BGE B.W. Doroshuk '

--BGE Claudia Craig . NRC/NRR/PGEB Robert Palla NRC/NRR/SCSB lan Jung NRC/NRR/SPSB Thomas Kenyon NRC/NRR/PDND ,

Rich McLean MD Department of Natural Resources David S. Austin BGE Karl Eser BGE i Mike Fallin Scientech Jim Bennett BGE-Rob Cavedo BGE ,

BB Mrowca BGE.

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I Attachment 1

E tire cycie management Projec Severe Accident Mitigation Alternatives  :

License Renewal Presentation NeilHaggerty January 7,1999 99 003 Slide ##

Attachment 2

M Ufe Cycle Management Projec Pre-Initiator Actions

• Pre-initiators would have small effect on CDF Will be included in CCPRA Model Due to small effect on CDF, pre-initiators are not expected to change any SAMA conclusions, therefore, we do not plan to include in SAMA analysis.99-003 Slide ##

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E Life Cycle Management Project Comparison of Tables (75 & (8)

. Table (7) shows reduction in particular category.

Table (8) shows overall CDF reduction.

• If change affects post-core damage containment release (Level 2), overall CDF will not change, but individual categories will be affected (increase or decrease).

• Example - SAMA No. 23 - CS System improvement

- DHR and IC Intact Categories increase

- DHR and IC Late Release Categories decrease

- Increases & Decreases cancel out

.~. Overall CDF change = negligible 99-003 Slide ##

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Life Cycle Management Project l l

Conservatism of " Saved Sequences" Method ER Page 4-29, "...this approach requires several conservative analysis techniques to achieve bounding results."

• For SAMAs, saved sequences is very accurate, as truncation issue does not play a significant role.

• But, dependency changes are more difficult to evaluate.

• Conservatively evaluated by setting all systems which i formally supported the broken dependency to success. l Example: Battery Reliability

- Improve bus failure probability only - A CDF =2.56E-06 (10.2%)

- Make battery capacity so large that EDG battery support not l req'd.

A CDF =1.83E-05 (73.1 %)99-003 Slide ## i i

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[ Life Cycle Management Project SAMA Cost Estimates Costs were not estimated if:

1. Based on engineering judgment, cost would greatly exceed benefit;

2. SAMA was determined to be unfeasible;

3. SAMA was determined to be inapplicable to CCNPP;

4. Conceptual SAMA benefit could not be realized;

5. SAMA could result in undesirable effects that were not considered in Benefit evaluation.

• Detailed discussion is provided for SAMAs in question. .3 sno. ..

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. i Life Cycle Management Project 1

SAMA No. 2 Install an additional swing Salt Water pump 1

• "Best Estimate" Benefit = $182,000 (U-1); $273,000 (U-2)

Estimated Cost of Enhancement >$5,000,000 1 1

l Basis I

+ Would either require installing swing pump in occupied pump bay, or building an additional intake structure.

Either option would be costly.

Cost of pump, piping, structure, engineering, etc. would be I in millions of dollars.99-003 Silde ##

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Life Cycle Management Project SAMA No. 5 Install Fire Protection Feed to Component Cooling Water Syst.

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• "Best Estimate" Benefit = S383,000 (Unit 1); $767,000 (Unit 2)

• Cost of Enhancement >S1,100,000 Basis j

• Benefit provided in Environmental Report = $565,000 did not include:

- Cost of installing return line from CC System to Pre-Treated Water Storage Tank (minimum cost = $500,000), material handling cost (18% of material costs), allowance for funds used during construction, AFUDC (25% of total), etc.

- Revised Cost of Enhancement >S1,100,000 per unit I

99-003 Slide ##

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Life Cycle Management Project SAMA No.11 Install a CTMT. vent largo enough to remove ATWS decay heat Approach #1 - Install primey ctmt. vent to remove ATWS decay heat

- BWRs blowdown RCS on an ATWS to create a void (negative reactivity)

- SAMA would relieve pressure from primary to secondary containment

- N/A for PWRs , c. benefit = $0 Approach #2 - Install primary syst. vents to remove normal or ATWS decay heat

- Assumes 50% of decay heat removal scenarios are eliminated with almost all ATWS scenarios eliminated

- The maximum calculated benefit = $5,430,000

- Large vents would allow rapid RCS inventory release and decay heat removal

- Cost of additional, independent RCS vent valves large enough to allow rapid RCS inventory release would exceed cost of replacing PORVs (SAMA #77)

-- Estimated COE >>$6,000,000 99-0V SIMe ##

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M Life Cycle Management Projec SAMA No. 24 Install a passive Containment Spray System

• Maximum Benefit = $542,000 (U-1)

• Estimated Cost of Enhancement >$5,000,000 1

Basis

• Would require installing a tank above the CS header ring.

• Cost of a tank above the containment dome would be in millions of dollars.99-003 Slide ##

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I Life Cycle Management Project .

1 SAMA No. 33-c Auto cross-tie between 125VDC Buses 11 and 21 Maximum Benefit = $712,000

• Estimated Cost of Er.hancement > $1,300,000 per unit l Basis

• Cost of ATS would be similar to SAMA No. 49 ($1.8M)

• Cost of 3 batteries, new racks, engineering, etc. would be > $800K l

• Would probably also require two-unit outage (common equip.)  :

• Total cost for two units > S2.6M ($1.3M/ unit)

• NOTE: if additional batteries would not fit in existing rooms, structural mods would cost millions of dollars. l l

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Life Cycle Management Project SAMA No. 35 increase / improve DC bus load shedding 1

• Maximum Benefit = $416,000 1 Estimated Cost of Enhancement = n/a Basis Current load shedding scheme gives 4-5 hr. battery life. ,

Benefit was calculated based on attaining 24 hr. life.

Calculations performed for SBO Rule indicated that best possible ,

load shedding scheme will not result in > 5 hrs.

..* conceptual SAMA Benefit is not possible!

99 003 Slide ## 1 I

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Life Cycle Management Project SAMA No. 41 Develop a severe weather conditions procedure Maximum Benefit = $456,000 i

Basis i

• Benefit based on eliminating risk from hurricanes, tornadoes and long duration loss-of-offsite power scenarios.

• BGE already has severe weather procedures: j

- ERPIP 3.0 -Immediate Actions  !

- EOP Loss of Offsite Power

- EOP Station Blackout  !

• Maximum Benefit could only be attained if plant is shut down j whenever a remote possibility of severe weather condition exists.

This is not practical!

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Life Cycle Management Project l SAMA No. 66-a Enhance flood mitigation procedures

• Maximum Benefit = $352,000 Maximum Benefit assuming SAMA No. 66-b implemented is unknown at ,

this time, but would be less than $170,000.  !

• Estimated Cost of Enhancement = $30,000 Basis SAMA 66-b will eliminate at least 50% of max benefit.

Flood risk is due to numerous flood scenarios. Procedure enhancements must focus on specific scenarios.

Exact benefit will not be determined until potential hardware modifications are resolved.

FLOOD Module of PRA model being revised. Based on results, procedure change may not be beneficial.

• This issue will be re-evaluated following disposition of SAMA 66-b and revision to the FLOOD Module.  !

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l Life Cycle Management Project SAMA No. 66-b Flood mitigation hardware modifications (Install water-tight doors in SRW Pump Room)

• Maximum Benefit > $1,000,000 (SRW Room only)

• Estimated Cost of Enhancement = $100,000  ;

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Basis I Benefit is based on preventing flood from propagating to/from SRW Pump Room (60% of total plant flooding risk) j Cost estimate is preliminary. Includes: labor, material, l engineering.  !

Potential modification will be processed i.a.w. CCNPP modification process.

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99-003 Slide ##

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1 Life Cycle Management Project l SAMA No. 71 Enhance procedures for local manual operation of AFW

• Maximum Benefit = S2,375,000 ,

• "Best Estimate" Benefit = negligible i Basis

• Benefit modeled by setting AFW human actions to success.

• Local manual control of AFW is addressed in:

- EOP-3: Loss of All Feedwater

- EOP 7: Station Blackout

- AOP-7D: Loss of Instrument Air

• Changes to these procedures to focus specifically on AFW ops would take operator attention away from other safety functions. ,

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• Max benefit would be offset by increased risk of other functions.

• Therefore, best estimate benefit would be negligible. I 99-003 Slide ## .

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SAMA No. 72 l Install a diesel genen. tor to drive either M/D or T/D AFWPs

• Maximum Benefit = S440,000

• Estimated Cost of Enhancement >> $1M Basis

• >>$1M to install a Diesel engine to drive the turbine-driven '

AFW pumps, as rooms are not designed for this purpose.

• . >>$1M to install a diesel generator to drive the motor-driven AFW pumps

- equipment, electrical tie-ins, engineering, installation, etc.

99 003 Slide ##

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Life Cycle Management Project SAMA No. 73-a Manual Fire Protection feed to Steam Generators

• Maximum Benefit = S3,288,000

• Estimated Cost of Enhancement >$5,000,000 Basis Benefit estimated by assuming AFW functions successful (except human actions)

To achieve full benefit:

- Upgrade FP System to meet secondary side pressure requirements

- Revise procedures and training to align FP System connection

• Cost of Enhancement >$5,000,000 99 003 slide ##

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4 Life Cycle Management Project i

SAMA No. 73-b Automatic Fire Protection feed to Steam Generators

• ' Maximum Benefit = $4,954,000 Estimated Cost of Enhancement >$7,000,000 Basis Benefit estimated by assuming AFW function successful (including human actions)

To achieve full benefit:

- Hard-pipe connection downstream of AFW block valves

- Upgrade FP System to meet secondary side pressure requirements

- Controls to automatically transfer FP System to AFW System, when required.

99 003 Slide ##

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SAMA No. 76 Reduce support system requirernents for feedwater system.

• Maximum Benefit = $3,288,000 Estimated Cost of Enhancement > >$10,000,000 Basis Cost is driven by mod to provide diesel backing to NSR buses Existing EDGs can not support condensate and condensate booster pump loads

• To achieve Benefit, BGE would have to install new DGs a

COE is supported by cost of installing No. OC DG in 1995 91H)03 Slide ##

l Life Cycle Management Project SAMA No. 78 Provide capability for diesel-driven, LP vessel make-up i

• Maximum Benefit = $236,000 Estimated Cost of Enhancement >> $1,000,000 Basis Modification would include:

- installing a diesel-driven pump to provide redundancy to LPSI pumps

- piping and valves for supply / discharge of diesel-driven pumps

- engineering, maintenance, training, procedures, etc.

Cost of this modification is estimated to exceed $1M.99-003 Slide ##

Life Cycle Management Project SAMA No. 80 Implement an improved RWT make-up procedure

• Maximum Benefit = $247,000

+ B/E factor = SE-02; Correction Factor = 0.60

• "Best Estimate" Benefit = $7,400 Estimated Cost of Enhancement = $10,000 Basis Benefit was based on the assumption that procedural changes could eliminate Inter-System LOCA and SGTR frequencies.

CCNPP procedures already address RWT make-up:

- EOP-5, Loss of Coolant Accident; OI 24H, Transferring Water to the RWTs

.. This SAMA will not effectively reduce ISLOCA/SGTR frequencies, and actual benefit is negligible.

99 003 Slide ##

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[M tire cycie Management Project SAMA No. 82 Ensure plant air compressors are diesel-backed.

• Maximum Benefit = S262,000

• "Best Estimate" Benefit = S0

• Estimated Cost of Enhancement = n/a Basis

• Conceptual benefit estimated by setting frequency of AFW air-related failures to zero.

• Currently, CCNPP design includes the ability to power plant air compressors from the EDGs. This plant improvement is not yet credited in risk model.

• AOP-7D - Loss of Instrument Air addresses cross connecting PA to other unit's IA

.. this SAMA could not reduce frequency of AFW air-related failures, and actual benefit is negligible.99-003 Slide ##

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Life Cycle Management Project SAMA No. 88 l

Remove the PORV lift on high pressurizer pressure. j I

• Maximum Benefit = $85,000 (U-1); $93,000 (U-2) l Estimated Cost of Enhancement > $125,000 l l

Basis

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Same Benefits as SAMA No. 48-o j Cost of implementing this SAMA would be much greater than the  ;

procedure change proposed for SAMA No. 48-b

.. Negative Net Value for either Unit l

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M tire cycie Management Project SAMA No. 90 install digital large brc ak LOCA early detection instrumentation ,

• Maximum Benefit = $120,000 Estimated Cost of Enhancement = $475,000 Basis Benefit is based on conservative assumption that a detection system would reduce LBLOCA frequency to zero.

• COE is based on assumption that system would be similar to Loose Parts Monitoring (LPM) System.

• Cost of LPM System was S950,000 for both Units. ($475K/ unit)99-003 Slide ##

Life Cycle Management Project SAMA No. 92 Add diesel-backed power to Demin Water Make-up pumps  :

• Maximum Benefit = e717,000 (both units)

• Estimated Cost of Enhancement = $752,000 (common)  :

• Net Value = ($33,000)

Basis

• Maximum benefit does not include Best Estimate factors, but I includes factor of 2.5 to account for increased U-2 SRW dependency.

• Cost of Enhancement same as provided for SAMA #74.

• SAMA benefits equipment common to both Unit i, therefore COE is also applied to both Units.99-003 Slide ##

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M tire cycie uanagement Project l l

SAMA No. 94 i l

Replace ECCS pump motors with air-cooled motors.

• Maximurn Benefit = $214,000

• Estimated Cost of Enhancement > $1,000,000 Basis Cost of air-cooled motors (3 HPSI,2 LPSI), labor, i engineering (including revised room heat-up cales),

etc. would exceed $1,000,000 Modification may require enhanced room coolers  !99-003 Slide ##

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m M tire evcie uanagement Projec SAMA No. 96 l Stagger HPSI pump use after a loss of Salt Water room coolers.

Basis for estimated Costs and Benefits discussed in RAI I response (12/3/98)

Additionally, NRC guidance recommends against stopping accident mitigation equipment when needed

- IN 97 Crediting of operato: actions in place of automatic '

actions and modifications of operator actions, incl. response

!imes Based on the discussion in the RAI response, the actual benefit for this procedure change, if any, would be negligible.99-003 Slide ##

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1 Life Cycle Management Projec i

Implement Plans for SAMA No. 66-b i

• An Engineering Service Package (ESP) has been issued to evaluate potentialimplementation of a modification to install a water-tight door.

• ESP will ensure proposed modification is evaluated in accordance with CCNPP modification process.

• Modification will not be implemented if determined to violate safety or design basis requirement.99-003 Slide ##

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[M tire cyci Management Projec RAI Response Figure #1

• Title results in confusion about information presented 4 CDF Risks are presented

- Loss of Inventory Control

- Loss of Decay Removal

- ATWS

- Containment Bypass l

• Containment Release related to size and timing

- Small or Large Release i

- Late Release

- Containment Intact

. Table 1 describes both CDF/ Containment Release 99-003 Slide ##

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E tire cycie uanagement Project Derivation of " Top 10" SAMA List

• Per RAI Response, we considered:

- 23 SAMAs subjected to full cost-benefit analysis

- SAMAs screened due to COE>$2.3M

• All SAMAs were considered in response to question.  !

- Doubled SAPE and SAOC

- Included SAOSC and SRPC

- Assumed "Best Estimate" factors equal to 1.00

• Results unchanged - No "new cost-beneficial SAMAs identified.99-003 Slide ##

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[M Life cycie Management Project Revised Population Projections

• Population Projection Changes:

- Washington, DC +2.46%

- Calvert County +0.00%

- Charles County - 2.19%

- St. Mary's County +9.55%

- Prince George's County - 4.87% ,

- Anne Arundel County +2.31 %  !

- Montgomery County +0.00% 4

- Kent County, DE - 5.29%

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- Sussex County, DE +9.79%

- Virginia Counties +0.00%

Overall Change - 0.15%

99-003 Slide ##

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Life Cycle Management Project l Relationship between ACDF and SAOSD l

ER Page 4-26 Wo = We + Woto

• ER Page 4-25 Wo = R(FDo)s ((1-e*yr}

• ER Page 4-26 Woro = R(F )tro)s([1-e*yr}{[1-e ""yrm}

• Wo = R(FDo)s ([1-e*yr} + R(FDero)s([1-e*yr}{[1-e ""yrm}

+

Wo = RF([1-e*]/r} ((Dio}s + (Dtro)s ([1 e""}/rm} j i

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Occupational Dose Term = ((Do)s + (i>tro)s ([1-e ""]/rm}

]

• (Do)s = immediate Dose = 3,300 person-rem (Dtro)s = Long-term Dose = 20,000 person-rem

• r = real discount rate = 7%

+ m = years over which long-term doses accrue = 10 years Occupational Dose Term = ((Do)s + (Doro)s ([1-e ""]/rm} l

= (3,300) + (20,000) ([1-e-(.07)(10)y(0.07)(10)} l

= 17,683 person-rem / accident I By multiplying this term by the accident frequency (F), you arrive at the person-rem for that event, b  ;99-003 Slide ##

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Best Estimate Rationale and Methodoloav

+ Uncertainties vs. "Best Estimates"

-analysis approach defines approximate level of risk, rather than being a detailed risk assessment.

-adopts typical accident analysis practice of addressing uncertainty through use of analytical margin (i.e., conservatism), rather than through a formal uncertainty analysis.

-providing substantial margin in every parameter would yield a final result so conservative that it would be totally useless.

99403 Slide ##

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E Life cycie management Project "Best Estimate" Rationale and Methodolociv

• Adjustment Factors - RAI Response page 17

- Best Estimate" Adjustment Factor

• Estimates adjustment to convert " saved sequences" Benefit to

" full plant model quantification" method.

• Double SAPE and $AOSC to account for changes in economic and evacuation time assumptions.

- Correction Factor

• Accounts for known changes to modeling techniques and assumptions based on updated information.

- Unit 1/ Unit 2 Adjustment Factor

• Accounts for configuration differences between units.

Factors for individual SAMAs will be addressed, if requested.99-003 Slide ##

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. l E Life Cycle Management Project Best Estimate Rationale and Methodoloav i

. SAMA No. 45 - FP System for EDG Cookng l

- APE = S110,119 - AOSC = $881,394

- AOC = $54,476 - RPC = $229,454

- AOE = $11,921 4 "B/E" Factor = 0.53 I Correction Factor = 1.00 U1/U2 Factor = 4 Best Est. = [2($110,119 + $54,476) + S11,921 + $363,609

+ $229,454]

• 0.53

• 1.00

= $495,000 (Unit 1)

= $1,995,000 (Unit 2)99-003 Slide ##

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Life Cycle Management Project Best Estimate Rationale and Methodoloav

+ SAMA No. 68

- Bounding" benefit estimated by setting Unit 2 AFW air-related function to success. Assures air is available to support alignment of Pump 23 to Unit 1.

- Best Estimate for Lower Bound estimate would be approx.

20% lower, as accumulator would not provide air for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

- Best Estimate for Upper Bound estimate would be approx.

20% higher, as it is possible that accumulators could provide other benefits. (e.g., flow control)

- As a result of Upper Bound increase, overall"Best Estimate" Benefit is higher than " Bounding" Benefit.99-003 Slide ##

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Life Cycle Management Project BGE PRA Staff SAMA identification Method Risk Significant issue Determination Method BGE used two PRA staff members with over 18 years of combined Calvert Cliffs PRA experience to identify potential SAMAs. The experience includes:

- Participated in the Development of the entire CCPRA model including Event Sequence Diagrams, Plant Model Rule Development, and most of the System Modeling;

- Performed numerous Sequence Examinations during Plant Model Rule Development; and

- Performed Multiple System importance Runs in support of Critical Risk Assessments such as the identification of the Maintenance Rule Risk Significant Systems.99-003 slide ##

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Life Cycle Management Project SAMA identification Approach Identified generic industry-identified SAMAs from previous analyses.

Customized generic industry-idenPfied SAMAs. -

- As discussed on page 4-27 of the Environmental Report, when possible, each of the generic industry-identified SAMAs was customized to become a site-specific SAMA.

Identified Site-Specific SAMAs.

- Eleven additional site-specific SAMAs were identified based on experience with Calvert Cliff's internal events PRA, with consideration given to:

• significant plant issues which contributed to large numbers of sequences, such as loss of decay heat removal scenarios; and

• issues which indicated a higher likelihood of being risk-beneficial, such as changing certain ESFAS/AFAS/RPS logic to 3-of-4.

Considered seven improvements identified by the IPE.99-003 slide ##

I cc:

Mr. Joseph H. Walter, Chief Engineer President' .

Public Service Commission ~of 4 Calvert County Board of '. Maryland j Commissioners Engineering Division )

175 Main Street 6 St. Paul Centre  !

. Prince Frederick, Md 20678 Baltimore, MD 21202-6806 I James P. Bennett, Esquire Kristen A. Burger, Esquire  !

Counsel: Maryland People's Counsel Baltimore Gas and Electric Company 6 St. Paul Centre P.0, Box 1475 Suite 2101 Baltimore, MD 21203 Baltimore, MD 21202-1631 Jay E. Silberg, Esquire .

Patricia T. Birnie Esquire I Shaw, Pittman, Potts and Trowbridge Co-Director 2300 N Street, NW . .

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Maryland Safe Energy Coalition Washington, DC 20037 P.O. Box 33111.

Mr. Thomas N. Pritchett, Director -

NRM Mr.'Loren F. Donatell Calvert Cliffs Nuclear Power Plant NRC Technical Training Center

1650 Calvert Cliffs Parkway .5700 Brainerd Road Lusby, MD 20657-4702 - Chattanooga, TN 37411-4017

' Resident Inspector Mr. Charles H. Cruse c/o.U.S. Nuclear Regulatory . Vice President - Nuclear Energy Commission Baltimore Gas and Electric Company P.O. Box 287 Calvert Cliffs Nuclear Power Plant St. Leonard, MD 20685 . 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702

. Mr. Richard I. McLean, Manager Nuclear Programs _. Mr. Roy Denmark .

Power Plant Research Program Federal Activities Office Maryland Dept. of Natural Resources U.S. Environmental Protection Agency i Tawes State Office Building, B3 Region lli Annapolis, MD 21401 841 Chestnut Building

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. Regional Administrator, Region I U.S. Nuclear Regulatory Commission . Mr. J. Rodney Little 4

~ 75 Allendale Road - Director and State Historic Preservation L' M of Prussia, PA 19406 Officer 100 Community Place Crownsville, MD 21032 l l

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-o i: Mr. John Wolfin j.,

, Supervisor - Chesapeake Bay Field Office ~Mr. Daniel L. Larcamp U.S. Fish & Wildlife Service Assisant General Counsel 177 Admiral Cochrane Drive - '

Electric Rates and Corporate Regulation Annapolis, MD 21401 Federal Energy Regulatory Commission

- 888 First St., NE Ms. Barbara Schroeder Washington, DC 20426 l National Marine Fisheries Service

' Office of Protected Resources Mr. Roland G. Fletcher, Manager

1315 East-West Highway. ,

Radiological Health Program

!i Silver Spring, MD 20901 Air and Radiation Management L Adminsitration -

L .. Merrilyn Zaw-Mon, Director Maryland Department of the Environment Air and Radiation Management 2500 Broening Highway y Administration Baltimore, MD 21244  ;

Maryland Department of the Environment j 2500 Broening Highway Doug Walters l

- Baltimore, MD 21244 Nuclear Energy Institute '

1776 l Street, N.W.

H. Russell Frisbey, Jr., Chairman Suite 300 Maryland Public Service Commission Washington, DC 20006 16th Floor 6 St. Paul Street Barth Doroshuk

- Baltimore, MD 21202-6806 Baltimore Gas and Electric

, 1650 Calvert Cliffs Parkway Dorchester County Commissioners Lusby, MD 20657-4702 County Office Building P.O. Box 26 National Whistleblower Center Cambridge, MD 20650 - 3233 P Street, N.W.

Washington, DC 20007 I St. Mary's County Commissioners P.O. Box 653 l i

- Leonardtown, MD 20650 -

l Charles County Board of County

. Commissioners P.O. Box B I Government Building La Plata, MD 20646 Mr. David Lewis i

^ Shaw, Pittman, Potts, and Trowbridge - i

2300 N Street, NW I

- Washington, DC ~ 20037 L

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