ML20248E789

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Forwards Discrepancy Repts (Drs) Identified During Review Activities for Independent Corrective Action Verification Program
ML20248E789
Person / Time
Site: Millstone Dominion icon.png
Issue date: 06/01/1998
From: Schopfer D
SARGENT & LUNDY, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
9583-100, NUDOCS 9806030448
Download: ML20248E789 (29)
v • d • e


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%(g Cf Don K. Schopfer Senior Vice President 312-269-6078 June 1,1998 Project No. 9583-100 Docket No. 50-423 Northeast Nuclear Energy Company Millstone Nuclear Power Station, Unit No. 3 Independent Corrective Action Verification Program United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 I have enclosed the following discrepancy reports (DRs) identified during our review activities for the ICAVP. These DRs are being distributed in accordance with the Communications Protocol, PI-MP3-01.

I have enclosed the following four (4) DRs for which the NU resolutions have been reviewed and accepted by S&L.

DR No. DR-MP3-0254 DR No. DR-MP3-0580 DR No. DR-MP3-0514 DR No. DR-MP3-1009 Please direct any questions to me at (312) 269-6078.

Yours very truly, Q7 & '

D.K.S pfer I SeniorVice President and ICAVP Manager DKS:spr Enclosures Copies: \

E. Imbro (1/1) Deputy Director, ICAVP Oversight T. Concannon (1/1) Nuclear Energy Advisory Council J. Fougere (1/1) NU mNesvpwswo601 a. doc g\

9006030440 930601 gO .

PDR ADOCK 05000423 )

! -- P PDR l

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55 East Monroe Street Chicago IL 60603-5780 USA 312-269-2000

1 i

Northeast Utilities ICAVP DR No. DR-MP3-0254 Millstone Unit 3 Discrepancy Report Review Group: Accident Mitgebon DR RESOLUTION ACCEPTED Review Element: Maintenance Procedure p

Diecipline: I & C Deshn Discrepancy Type: Calculeton O va '

(G) No System / Process: N/A NRC Sigedficance level: 4 Date FAXad to NU:

Date Published: 10/30s7 Discrepancy: Narrow Range Pressurizer Pressure - Calibration Data l Conversion (Discrepancy for Loop RCS*PT455)

Ducrip60n: The ICAVP reviewed the following documents in order to evaluate the pressurizer pressure function setpoints:

Referances:

1) FS/.R Figure 7.2-1, sheets 6,8,11,18 and 19
2) Precedure 3442C10, Pressurizer Pressure Narrow Range Char.nel 1 Calibration, Rev.1
3) l&C Form 3442C10-1 Rev.1, Data pages 3, and 8 through 17 of 19
4) Technical Specifications Ma'1ual, Table 2.2-1 items 9 and 10 Amendment 114; Table 3.3-4 item 1.d Amendment 60, and item 9.a Amendment 98 in reviewing these documents the ICAVP identifies the following discrepancies:

a) The use of the Engineering Unit Conversion Factor shown in the Reference 3) data sheets, titled 'SETPOINT .

REFERENCES", will not convert the calibration data to the ,

acceptable setpoint values shown in Reference 4).

SETPOINT

REFERENCE:

TECHNICAL SPECIFICATIONS (TS) Table 2.2-1, item 10, (TRIP SETPOINT <=2385psla);

imA=50 PSIA (from Page 8 of Data Sheets).

For example in order to convert the calibration data of 17.664 I mA (Data sheet page 8), to a pressure value and compare it with j the acceptance criteria contained in the TS of <=2385 psia the following calculations must be performed: I 1mA=50 psi; Pressure Transmitter (PT455) offset =1700 psia (from Page 3 of Data Sheets, including head correction);

Calibrated Pressure =1700+[(mA-4)x50]=2383.2(psia).

b) The Reference 1) Functional Diagram sheets contain a number of Notes. Some of these include a statement " Supplied by Others'. This does not reflect the MP3 as-built configuration.

Review I Valid invalid Needed Date initiator: Balodra, V. E.

O O O 9/24s7 i

VT Lead: Rahoja, Raj D D 0 0 s/24s7  :

w y pey y v oxm ~

Pnnted 6/1/96 9.57:52 AM Page 1 of 3 l l

ICAVP DR No. DR-MP3-0254 Northeast Utilities Millstone Unit 3 Discrepancy Report.

st2ss7 v7 Mor: Schopfer, Don K B O O IRC Chmn: singh. Anand K O O O or27/97 Date:

HvAuo:

Date: 5/29/98 )

REs0LUTKW: Disposition:

NU has concluded that the issue reported in Discrepancy Report, j DR-MP3-0254, does not represent a discrepant condition.

item a)The imA=50.0 PSI reference value is for information only and is not an engineering conversion equation. It simply relates current to pressure such that, if the current input changes by 1 mA than the pressure output will change by 50 PSI. Therefore, the factor imA=50.0 PSI of reference 3 is correct. The Pressurizer Pressure Narrow Range Channel 1 Calibration procedure does not require the test technician to perform any conversions. The acceptance criteria for this surveillance is in mA. When the cur ent value reaches the allowable value and the bi-stable trips within the procedure acceptance criteria range the instrument passes.

Item b)The Functional Diagram issue was identified during the recent 50.54f FSAR review. NU recognized that they are responsible for all elements on the Westinghouse functional diagrams (NU drawing 25212-39001- SH4007, SH4009, SH4012, SH4020 and SH4019). However it was decided that the note (s) provide helpful information by identifying those elements that were part of the Westinghouse Nuclear Steam Supply System (NSSS) supplied package versus the elements that were part of the NU or(Architect Engineer) AE scope of supply. The notes and drawing do reflect the NU conditions from the NSSS vendor perspective as well as what scope Westinghouse Nuclear Energy Systems (NES) and NU / AE were responsible for. The drawings provide usefulinformation and are acceptable to NU.

Sign!ficance Level crXerla do not apply here as this is not a discrepant condition.

Conclusion:

NU has concluded that the issue reported in Discrepancy Report, DR-MP3-0254, does not represent a discrepant condition.

Item a)The factor in the l&C Form 3442C10-1 Rev.1 of imA =

50.0 PSI is correct as is. It is not used in the Pressurizer Pressure Narrow Range Channel 1 Calibration surveillance procedure. The factor is for information only and should not be interpreted as an engineering conversion equation.

Item b)The notes and drawing do reflect the NU conditions, as well as, what scope Westinghouse Nuclear Energy Systems (NES) and NU/AE were responsible for. The drawings provide useful information and are acceptable to NU.

Rinnificance Level cr'teria do not anniv here as this is not a

' )

Printed 6/1/96 9.57.53 AM Page 2 of 3 l

_. . _ _ _______-_______________a

Northeast Utilities ICAVP DR No. DR-MP3-0254 Ministone Unit 3 Discrepancy Report discrepant condition.

Previously identmed by NU? U ves (9) No Non Discrepent Condition?U vos fS) No Resolut6on Pending?O yes @ No Raoiution uare.oivedrO va @ No Review initiator: Peebles. W. R.

VT Lend: Rahele, Raj D VT Mgr: Schopfer, Don K RC Chmn: Singh, Anand K Date: 5/29/98 sL carments: Item a): ICAVP finds the NU response acceptable.

The l&C and/or Operations Supervisors authorizing and verifying the calibration require a direct link to the current Amendment of the Technical Specifications from the l&C Form.

The ICAVP does not dispute the fact that the acceptance criteria for the surveillance is in mA, nor, that the test technician does not perform any conversions. Since the three quoted items in the Technical Specification Manual are based on Amendment 114, Amendment 60, and Amendment 98, therefore, without a reference to an Engineering Calculation and its revision number, the basis of the conversion to the Technical Specification value can not be verified.

The SETPOINT REFERENCE, as used on the Form with a general reference to TECHNICAL SPECIFICATIONS Table items, without a Specific Engineering Calculation reference or the actual engineering conversion equation, does not provide a link to the current Technical Specifications.

We recommend that this be reevaluated and incorporated as an action item in the next Calibration Procedure review cycle.

Item b): Response acceptable. However, in our opinion from a human factors standpoint, this adds confusion to the information presented.

Note: Due to a typographical error, the original comment indicated that this response was unacceptable. This error has been corrected.

Printed 6/1/96 9 57.53 AM Page 3 of 3 J

Northeast Utilities ICAVP DR No. DR-MP3-0514 Millstone Unit 3 Discrepancy Report l

Review Group: System DR RESOLUTION ACCEPTED Review Element: system Design pg ,

D6scipline: Mechancel Dosign gg Discrepancy Type: Test Requirements SystemProcess: HVX jg NRC Sionmcence level: 4 Date faxed to NU:

Date Published: 11/13/97 D6screpency: Containment Enclosure Building Negative Pressure

Description:

During review of the Supplementary Leak Collection and Release System (SLCRS) a discrepancy in the negative pressure required to be maintained in the Auxiliary Building at elevation 24'-6" was identified.

SER Section 6.2.3 states that the capacity of the SLCRS is sufficient to reduce and maintain a pressure of -0.25 in. water gauge throughout the enclosure building and contiguous l

buildings within 1 min after the accident, assuming wind velocity of 22 mph.

FSAR Section 6.2.3.3 states that the negative pressure is measured at Auxiliary Building 24-6 elevation and maintained per Technical Specifications at greater than or equal to 0.4 inches water gauge after a design accident (DBA). The 0.4 inch water gauge (iwg) negative pressure is measured at the Auxiliary Building 24-6 elevation in order to ensure a negative pressure in all areas inside the secondary containment boundary under most onsite meteorological conditions.

Drawing EM-2E-12 shows the high point of the containment structure enclosure as elevation 186*-2 3/4".

Calculation 92-071-339M3 Rev. O and change number 001 determine correction factors to account for the difference in pressure at the test location, elevation 112'-0" (top of SLCRS suction ductwork) and elevation 186'-2 3/4"(top of enclor,ure building) caused by differences in air temperature inside and outside the containment enclosure building. The 0.4 iwg negative differential pressure in FSAR Section 6.2.3.3 is the differential pressure at elevation 24'-8" needed inorder to maintain a 0.25 iwg negative differential pressure at elevation 112'-0" with O'F outside air temperature and 50'F containment enciosure building temperature. To maintain a 0.25 iwg negative differential pressure at the top of the containment enclosure building at these temperatures a 0.51 iwg negative differential pressure is needed at elevation 24'-6".

The calculation also contains a table that provides the required negative differential pressure at elevation 24'-6" for various indoor and outdoor air temperatures. For cases with the indoor air temperature lower than the outdoor air temperature, the required test differential pressure at elevation 24' 6" is less than - l 0.25 iwg which does not meet the requirement that all areas are {

l maintained at a -0.25 iwg differential pressure.

The 022t!On dcec net Mt;= the ;"r" of ^; nd 0- th p y de

.-_____-_-___a

1 1

ICAVP DR No. DR-MP3-0514 Northeast Utilities Milistone unit 3 Discrepancy Report pressure distribution around the containment enclosure building. )

Review l Valid invalid Needed Date j initiator: Stout, M. D. O O O 10'57/S7  !

I VT Lead: Neri, Anthony A B O O 1 ' '87 5 '/8'S7 VT Mgr: schopfer. Oc, K O O O l NtC Chmn: Singh, Anand K O O O $1/7'S7 1 Date: l INVALID:

Date: $/29/98 RESOLUTION: First Response NU has concluded that the issue reported in Discrepancy Report, DR-MP3-0514, does not represent a discrepant condition.

Proposed Technical Specification Change Request 3-30-93 contains a letter to the NRC dated 11/4/93 which recommends the changes to the Tech Specs and states in part on page B 3/4 6-7 paragraph 3/4.6.6.1:

"In order to ensure a negative pressure in all areas inside the secondary containment boundary under most meteorological conditions, the negative pressure acceptance criteria at the measured location is 0.4 iwg. It is recognized that there will be an occasional meteorological condition under which slightly positive pressure may exist at some localized portions of the i l

boundary.. "

On 12/8/93 the NRC issued Amendment 87 along with its Safety Evaluation approving the changes to the Tech Specs. This would supersede any prior statements found in SER section 6.2.3.

Furthermore, there are no piping and electrical penetrations above elevation 69'-9" in the containment liner (Reference CTMT pipe penetration drawing 12179-EP-121 A-10 and EP-121B-8.) Therefore, if a leak did occur, it would be below the SLCRS duct suction.

CCN 001 to Calculation 92-071-339-M3 provided the independent calculation to establish the minimum negative pressure required by the SLCRS test at elevation 24'-6" to render minimum negative pressure of 0.25 iwg at elevation 112'-0"(top of SLCRS suction duct, reference drawing EB-15M.) This is the basis that the NRC accepted. The Tables in the calculation on j pages 10 and 11 are based on the 186*-2 3/4" elevation. l Significance level criteria do not apply as this is not a discrepani condition.

Second Response (M3-IRF-1954)

NU has concluded that Discrepancy Report DR-MP3-0514, item l id, has identified a condition not previously discovered by NU Printed 6/1/98 9.58:52 AM Page 2 of 8 l

ICAVP DR No. DR-MP3-0514 Northeast Utilities Millstone Unit 3 Discrepancy Report which requires correction.

(1d) Fire Stops and Seals are govemed by the EM-60 series drawings in conjunction with specification SP-GD-001. The flex.

seal referred to is an architectural cosmetic feature. The

  • Rodofoam"(compressible material) was all removed, but the drawings referenced were not updated. The approved corrective action to CR-M3-98-0772 will revise the affected drawings. The affected documents are not operations critical.

(1) (General) Bypass Jumper 3-93-170 provided for the installation of two tubing penetrations to measure differential pressure across the Containment Enclosure. The Bypass Jumper was made a permanent modification. DCN DM3-S-1254-95 (copy attached) details location and installation of the permanent pressure taps.

(1a) The Hydrogen Recombiner Bldg is not within the SLCRS boundary, its common wall with the Containment Enclosure acts as a boundary for SLCRS. Differential pressure was measured in the MSVB which is drawr, down via the Enclosure Bldg. ,

therefore the MSVB differential pressure readings provide conservative indication of the Enclosure Bldg. differential pressure. This is not a discrepancy.

(1b) Same as above.

(1c) The measurement location was selected to eliminate the effect of wind velocity on the ac'ual DP measurement. During testing, the door to the extemal environment was opened to ensure the high side tap was reflective of extemal pressure.

This is considered to be a more reliable approach to measuring the DP as it eliminates any dynamic effect by wind pattems at the measurement location. Ref. drawing no. 25212-24196-00001 (12179-EB-358) Ventilation and Air Conditioning Service Building Sh. 2. This is not a discrepancy. l (2) The drawings referenced correctly show that the duct is blanked off and the sample room dampers normally closed.

l Although the statement that the blanked off duct is not consistent with the statement in the 11/4/93 submittal, the degree to which the NRC relied on this information is judged to be low. The SER for Amendment 87 makes no reference to the paragraph on page 14 of the 11/4/93 submittal, but places emphasis on the NRC l review of the test data usod by NNECo to justify the j measurement location. The SER also acknowledges that only l

parts of the contiguous spaces listed are included in the SLCRS boundary (ref. page 5, use of term " partially"). This implies that at some level in the supporting discussion surrounding the issuance of this amendment that the extent to which the spaces were included in the SLCRS boundary area was discussed and clarified. While the discussion in the text of page 14 is inaccurate to some degree, it is judged to have been insignificant or immaterial to the NRC approval of the amendment. The normally closed sample room dampers are acceptable because this room is outside the SLCRS boundary.

Printed 6m98 9.58 s3 AM Page 3 of 8 l

Northeast Utilities ICAVP DR No. DR-MP3-0514 l Millstone Unit 3 Discrepancy Report This is not a discrepancy.

(3) This concem was addressed in the 11/4/93 submittal in that an analysis was performed to determine the joint probability of occurrence of wind and temperature conditions which could l cause a reduction in the required build;ng DP. NNECo addressed this as a low probability condition in paragraph 3 on page 15 of the 11/4/93 submittal. The NRC reviewed NNECo's basis and accepted it in the Amendment 87 SER. This is not a discrepancy.

(4) The NNECo evaluation of IEN-88-76 was based on the joint probability of occurrence of the atmospheric conditions rather than the discreet frequencies. The NRC reviewed the NNECo logic and accepted it explicitly in the SER. The approved corrective action to CR-M3-98-0772 will retrieve this analysis for l

confinnatory review. Justification for the "<2% time" is detailed in Calculation XX-XXX-115RA, Rev. O. A copy is attached for your information. This is not a discrepancy.

l (5.1 & 5.2) The -0.51 ivg DP value cited would be required if the design were based on achieving a minimum of -0.25 iwg DP under all conditions. As noted in the 11/4/93 submittal, the proposed acceptance value of-0.4 iwg was not intended to bound all conditions.

(5.3) The extreme environmental conditions described in IEN 88-76 were addressed through the joint probability evaluation previously discussed and excluded on the basis that they occurred <2% of the time. (See attached calculation XX-XXX-115RA, Rev. 0) This is not a discrepancy.

The test rig locations listed on the Test Rig Location Diagram in IST 3-93-045 are explained on the attachment titled Test Rig Locations IST 3-93-045. (This is in response to S&L's request per NU/S&L telecon 3/25/98).

Licensing basis / design basis not affected by the discrepant conditions. NU considers the discrepant item id to be Significance Level 4. The corrective action will be completed post startup.

Attachments:

CR-M3-98-0772 with approved corrective action plan Calculation XX-XXX-115RA, Rev. O DCN DM3-S-1254-95 Test Rig Locations IST 3-93-045 Supplemental Response (M3-IRF-2322)

This response supplements M3-IRF-01954. At a meeting held on 4/14/98 at Millstone, S&L requested additionalinformation  ;

conceming the SLCRS Verification Test.

A copy of MP3 Surveillance Procedure SP 36141.3, Rev. 9, is attached to this transmission. Step 4.1.5.b is an instruction to Printed 6/U98 9.sS.s3 AM Page 4 of 8

~

ICAVP DR No. DR-MP3-0514 Northeast Utilities Millstone Unit 3 Discrepancy Report block open "at least one side of the Service Building east corridor north door (S-24-20)".

To supplement information provided in M3-lRF-01954, a copy of MP3 Surveillance Procedure SP 36141.3, Rev. 9, is attached to this transmission. Also, IST 3-93-046 was the last test performed in which multiple measuring points were used. The difference between the MSVB and the AB (PDIT212) readings (0.05) is insignificant. Both areas met the required negative pressure at 40 seconds and both areas were significantly more negative than 0.40" WG at 120 seconds.

Attachments:

SP 36141.3 Supplementary Leak Collection and Release Gystem Negative Pressure Verification Previously kletWined by NU7 O vos IO) No Non D6ecrepent CondMion?O vos f9) No Resolut6on Pending?O va + No RudakmUnrnhed70 va @ No Review initletor: stout. M. D.

VT t.eed: Neri, Anthony A O O O Sf29/98 VT Mgr: schopfer, Don K 1RC Chmn: sngh, Anand K O

Date: 5/29/98 SL Comments: Comments on First Response NU's response does not fully address the issues identified in the discrepancy report.

1) NU Letter B14669 dated November 4,1993, which transmitted )

the proposed technical specification change request for the supplementary leak collection and release system, provides a discussion for using a single point pressure measurement location. The argument was that there is a large open area between the various buildings and provides a table of the area of the openings. Looking at the areas provided in the letter it would seem that a single measurement location is reasonable.

However, when the physical details for the 4" shake space between the containment structure and the surrounding buildings, IST 3-93-045 test results, and IST 3-93-046 test results are reviewed it is not obvious that a single point pressure measurement at elevation 24'-6"is representative of the pressure for the whole structure.

a) IST 3-93-045 conducted on 10/24/943 measured differential pressures in the auxiliary building, ESF Building, and main steam valve building (per Attachment 1 Test Rig Locations). Differential ,

I pressures where not measured in the hydrogen recombiner building and the containment enclusure during the drawdown test.

b) IST 3-93-046 conducted on 10/27/93 measured differential pressures in the auH!iary building, ESF building, and main steam valve building (per Attachment 1 Test Rig Locations). Differential pressures where not measured in the hydrogen recombiner Printed 6/1/96 9-58.53 AM Page 5 of 8

r-Northeast utilities ICAVP DR No. DR-MP3-0614 Millstone unit 3 Discrepancy Report building and containment enclosure during the drawdown test.

c) The auxilary building elevation 24'-6" general area measurement records the differential pressure between the auxiliary building and the service building. Depending on the relative pressure of the service building to the outside, the actual auxiliary building differential pressure with respect to outside could be different than that read on 3HVP-PDIT212.

i d) Drawing EA-1S-1 section 5-5 shows a flex sealin the shake l space between the ESF building and Containment Stucture.

l Drawing EA-42A-12 does not show the flex seal. There were no open change documents posted against drawing EA-1S that removed the flex seal. In addition section 70-70 on drawing EC-32E-5 shows compressible material installed in the shake space near the removable slabs on the ESF Building Roof. If the flex seal at the bottom of the containment enclosure shown on EA-1S-1 or the compressible material shown on EC-32E-5 is installed, the ESF building does not appear to directly communicate with the containment enclosure.

2) NU Letter B14669 dated November 4,1993, page 14, states that there is a SLCRS duct connection for exhausting from the hydrogen recombiner building. Both P&lD EM-148E-12 and duct drawing EB-72A-6 show the exhaust duct openings blanked off and that damper 3HVR*DMP60 in the duct that exhausts from the sample room is normally closed. Therefore, there would be no direct SLCRS exhaust from the hydrogen recombiner building during secondary containment drawdown as implied in the letter.
3) As shown on P&lD EM-148E-12 and duct drawing EB-15M-10, SLCRS exhausts 6430 cfm from the containment enclosure at one location between columns C & D (auxiliary building side of the containment enclosure). Not all of the containment penetrations, shown on drawing EP-121 A-10 and EP-121B-8, are located in the same area (quadrant) as the SLCRS exhaust opening in the containment enclosure. For example, the penetrations into the hydrogen recombiner building are on the opposite side of the enclosure. As the radius of the containment structure is -75' exhausting from only one location does not ensure that leakage into the containment enclosure space is exhausted by SLCRS if thermal or wind effects cause the pressure differential to be less than .25 iwg in portions of the containment enclosure.
4) NU Letter B14669 dated November 4,1993, page 15, indicated that the combination of low outdoor temperatures and moderate wind speeds would occur less that 2% of the time. Based on FSAR Table 2.3-15, the 33-foot wind speed is between 4 - 12 mph 60.8% of the year and between 13 - 18 mph 18.77% of the year. Considering the containment structure as a cylinder, wind effects result in the pressure on the outside surface of the enclosure to vary significantly. With a 18 mph wind, the outside surface pressure for the containment enclosure varies from +0.15 iwg (O' azimuth) to -0.18 iwg (90' azimuth). A -0.25 iwg differential pressure readina at O' azimuth would result in a +0 09 Pnnted 61/96 9.58 53 AM Page 6 of 8

ICAVP DR No. DR-MP3-0514 Northeast Utilities Millstone Unit 3 Discrepancy Report I

iwg differential at 90' azimuth. A -0.40 iwg differential pressure reading at O' azimuth would result in a -0.06 iwg differential at 90*

azimuth. Neglecting thermal effects that occur in the winter, using a single measurement location could result in portions of the secondary containment not meeting the differential pressure requirement of .25 iwg (outlined in IE-IN 88-76) more frequently than the 2% of the time stated in the letter.

5) Using an outdoor air temperature of O'F and indoor air temperature of 50*F (ref. calc 92-071-339-M3, CCN 001, pg 6) the differential pressure required at el 24'-8" to maintain the differential pressure at the top of the containment enclosure at -

0.25 iwg is -0.51 iwg (ref. calc 92-071-339-M3, pg 10). The .40 iwg differential at el 24'-6" would ma!ntain a .25 iwg , differential with an outside a;r temperature of 20*F and an inside air temperature of 50*F. Note however, that based on New London, CT ASHRAE woather data, outside air temperatures are below 20'F more than 2% of the winter months. Therefore, to account for thermal effects only, the differential pressure at elevation 24'-

6" should be -0.51 iwg not -0.40 iwg.

This is considered a descrepant condition due to the following:

1. The -0.40 iwg differential pressure at elevation 24*-8" does not maintain the top of the containment enclosure at a .25 iwg differential pressure when thermal effects described in NRC Information Notice No. 88-76 are accounted for.
2. The differential pressure at elevation 24'-6"in the auxiliary building has not been established as representative of the pressure in the containment ench,sure and hydrogen recombiner building based on information received from NU.
3. The required differential pressure to offset normal wind effects on the containment enclosure has not been addressed.

Comments on Second and Supplemental Responses l NU's response resolves comments #1 and 3 above. NU's response does not resolve comment #2 regarding the differential pressure measurement location.

1. The differential pressure is measured between the auxiliary l

building el 24'-6" and the service building. NU's response indicates that the service building door to the outside is opened l

during testing. This requirement was not contained in surveillance procedure SP36141.3 " Supplemental Leak Collection and Release System Negative Pressure Verification" until 4/2/98 when Change 3 issued. This is considered a discrepant condition as tests performed prior to 4/2/98 may have been influenced by the service building pressure relative to the outside.

l

2. The differential pressure measurement location does not bound the differential pressure in the main steam valve building in all cases. The B-train winter mode test results for IST 3-93-036 show the MSVB differential pressure as beina 0.05 iwa less than that i Pmted 6508 9.58:s3 AM Page 7 of 8 L-________-_______

l Noceast utilities ICAVP DR No. DR-MP3-0614 Miiistone unit 3 Discrepancy Report measured in the auxiliary building. The results of the May 30, 1995 Train B SLCRS Negative Pressure Verification show a differential pressure at elevation 24'-6"in the Auxiliary Building of -0.425 iwg at 120 seconds and -0.45 iwg at 200 seconds.

Adjusting for the 0.05 iwg offset in the MSVB, the secondary containment differential pressure is -0.375 iwg at 120 seconds and -0.40 iwg at 200 seconds which does not meet the acceptance criteria of -0.40 iwg within 120 seconds. The results of the May 30,1995 Train A SLCRS Negative Pressure Verification show a differential pressure at elevation 24*-6"in the Auxiliary Building (3HVR-PDl210) of -0.475 iwg at 120 seconds and -0.475 iwg at 200 seconds. The B-train results for IST 390-014 run #3 shows the MSVB 0.35 iwg ( .11 - ( .46)) less than the auxiliary building. The A-train results on run #1 show the MSVB 0.09 iwg (-

.41 - ( .5)) less than the auxiliary building. Therefore, using differential pressure measured at elevation 24'6" of the auxiliary ,

building does not ensure that all areas of the secondary {

containment are drawn down to negative pressure within 120 seconds after an accident as stated in FSAR Section 6.2.3.3.

3. The measurement location between the auxiliary building and service building (northwest comer) on elevation 24'6" is influenced by the charging pump room ventilation system (fans 3HVR*FN13A/B and 3HVRTN14A/B). In the winter mode, air is supplied to the component cooling pump area and exhausted through the charging pump rooms. In the summer mode, air is supplied and exhausted from the component cooling pump area (ref. drawing EB-45C-13). The net exhaust airflow in this area influences the differential pressure measured and may mask an lower differential pressure in the containment enclosure during drawdown testing.

This DR is unresolved.

This DR is being reissued as a confirmed level 4 discrepancy.

We concur with NU that the issue regarding the fire stop and seals (item id) is a level 4 discrepancy.

We concur with NU that the use of the differential pressure measured at elevation 24'-6"in the auxiliary building for secondary containment drawdown time surveillance testing was approved by the NRC when Amendment 87 of the Technical Specification was issued. As NU is in compliance with the i technical specification this is not a discrepant condition. l However, as noted in our comments on the second and ,

supplemental responses above, we do not concur that this single l point measurement location is representative of the secondary containment differential pressure. This issue will be forwarded to  !

the NRC.

I Pmted 6/U98 9 58 53 AM Page 8 of 8 i

Northeast Utilities ICAVP DR No. DR-MP3-0580 Millstone Unit 3 Discrepancy Report Review Group; system DR RESOLUTION ACCEPTED Peterdial Operatniaty lseue Discipline: Mecherncal Design g Discrepancy Type: Liceneang Document SystemProcess: HVX NRC Significance level: 4 Date faxed to NU:

Date Putdished: 11/22/97 Discrepancy: Secondary Cont" '. ment Drawdown with SLCRS and ABVS

Description:

During review of the Supplementary Leak Collection and Release System (SLCRS) and the Auxiliary Building Ventilation System (ABVS) discrepancies regarding the required secondary containment drawdown time were identified.

Secondary containment drawdown requirements in the FSAR are:

FSAR Section 6.2.3.3 states that the SLCRS in conjunction with the auxiliary building filter system draws down the pressure to the minimum 0.4 inch negative pressure in 110 seconds from the time of emergency diesel generator breaker closure.

i FSAR Section 6.2.3.3 states that the SLCRS and ABVS is l required to drawdown the SLCRS areas to a negative pressure within 120 seconds after the accident. The negative pressure is measured at the Auxiliary Building 24-6 elevation and maintained per technical specifications at greater than or equal to 0.4 inches of water guage after a design accident.

I FSAR Table 1.9-2, SRP 6.5.1 B.5 states that the SLCRS draws j down enclosures contiguous to the containment to a minimum l negative pressure of 1/4 iwg in 60 seconds after SIS.

SER Section 6.2.3 states that the capacity of the SLCRS is sufficient to reduce and maintain a pressure of -0.25 iwg throughout the enclosure building and contiguous buildings within 1 minute after the accident, assuming a wind velocity of 22 mph.

The calculations that determine the secondary containment drawdown time and SLCRS altflow are calculations:

P(B)-843, Rev. O Supplementary Leak Collection and Release System P(B)-1089, Rev. O Establish Acceptance Criteria for Air Leakage l Through Pipe and Electrical Penetrations The objective of calculation P(B)-843 was to determine the required capacity of SLCRS and the time required for SLCRS to achieve a negative pressure of 0.25 iwg in the contamment enclosure building and contiguous buildings. The results of the calculation indicate that with a 9,500 cfm SLCRS fan capacity the drawdown time to -0.25 iwg is 30 seconds. Review of the calculation identified the following discrepancies:

1. Calculation does not provide references for the building s mal ..m a w www mie nA la tha e nin. .laa!an, ww ---- vv v viv - vw---. -.

}

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Northeast Uti;ities ICAVP DR No. DR-MP3 0580 I

Millstorm Unit 3 Discrepancy Report l 2. Calculation does not adequately account for differences in air density between the outside air (infiltration into building) and at j the inlet to the SLCRS exhaust fan. The air density ct the fan 1 inlet is lower than the infiltrating air due to heat gains in the building and the electric heater in the SLCRS filter unit. =

3. Assumes that fan flow is constant because the fan is equiped with variable inlet vanes. Neither P&lD EM-148E-12 nor specification 2176.430-141 show inlet vanes and associated controls for fans 3HVR*FN12A/128.
4. Calculation does not address wind effects on leakage through the containment enclosure.

Calculation P(B)-1089 determines the allowable leakage rates and exhaust airflows for the areas exhausted by the SLCRS fans. Review of the calculation identified the following discrepancies:

1. Calculation determined that an exhaust rate of 130 cfm was required for the hydrogen recombiner building,4950 cfm for the containment enclosure building and 1350 cfm for the main steam valve building. P&lD EM-148E-12 shows the exhaust openings for the hydrogen recombiner building being blanked off, no airflow exhausted from the main steam valve building, and 6430 cfm exhausted from the containment enclosure.
2. Calculation does not address wind effects on leakage through the containment enclosure. This results in under estimating the leakage through the containment enclosure.

In response to M3-RFI-00472 that requested the calculation (s) that determine the secondary containment drawdown time with the SLCRS assisted by the ABVS, NU in M3-IRF-00622 transmitted IST 3-93-45 and IST 3-93-46 which presented )

SLCRS and ABVS test data and calculation 92-071-339M3, SLCRS Drawdown Test Pressure Correctica Factor Calculation. i NU stated that the combination of these documents satisfies the request for the secondary containment draw down time with SLCRS and ABVS. Review of IST 3-93-045 SLCRS & ABVS Restest of PDCRs MP3-93-200 & 205 and IST 3-93-046 SLCRS

& ABVS Restest of PDCRs MP3-93-200 & 205 in Winter Mode from an engineering perspective identified the following discrepancies:

1. Plant conditions at time of the test did not correspond to postulated post-LOCA conditions. Therefore, not all heat loads that would be present during the postulated accident were presont. The tested drawdown time needs to be adjusted to address areas such as the main steam valve building that have the non-safety ventilation system that provides cooling during normal plant operating isolated on a SIS. Due to differences in heat gains present during test and accident conditions the tested draw down time will be faster than the accident condition time.

Printed 6/146 9:59:19 AM Page 2 of 13

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I Northeast Utilities ICAVP DR No. DR-MP3-0580 Millstone Unit 3 Discrepancy Report

2. Test did not record differential pressures and times for the recombiner building which is inside the secondary containment boundary.

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3. Test results do not identify SLCRS or ABVS system altflows during test. Technical Specification 4.6.6 .1 states that the SLCRS is considered operable with a flow rate of 7600 cfm to 9800 cim. Results need to be adjusted to correspond to minimum airflow conditions since the draw down time is directly affected by the SLCRS airflow rate.
3. The acceptance criteria of a 2.5 minute drawdown time to 0.4 IwD negative pressure in IST 3-93-045, Rev. O, Change 7 and IST 3-03-046 Rev. O, Change No.1 do not agree with FSAR drawdown times show above.

NU letter B15028 dated December 14,1994 submitted a proposed revision to Technical Specifications for the Supplementary Leak Collection and Release System. The proposed Section 4.6.6.1.d.3 Surveillance Requirement is

" Verifying that each system produces a negative pressure of greater than or equal to 0.1 inch Water Guage in the Auxiliary Building at 24'6" elevation within 60 seconds after a start signal and a negative pressure of Greater than or equal to 0.4 inches Water Guage in the Auxiliary Building at 24'6" elevation within the next 120 seconds." On pa0e 6 of the letter NU states "With the proposed negative pressure criteria for the secondary containment, it could be assummesd that all leakage into the secondary containment is filtered, since a sufficient negative pressure is achieved within one minute and the final required negative pressure is acheived within the next two minutes."

When the difference between accident and test heat loads, wind effects, and correction factor for the measured differential pressure are accounted for, not all areas within the containment enclosure will be at a negative pressure within 60 seconds.

Other Discrepancy Reports that address related issues:

DR-MP3-0514 Containment Enclosure Building Negative Pressure DR MP3-0030 Drawdown Times for Rod Ejection Accident and LOCA Review Valid invalid Needed Date initiator: stout, M. D. O O O 1o/24/97 VT Lead: Neri, AntNmy A O O O S o/3S7 VT Mor: schopfer, Don K O O O $ 5 /5'S7 IRC Chmn: singh, Anand K O O O iria/97 Dei.:

INVAUD:

]

Date: 5/29/98 RESOLUTION First Response

. i NU has concluded that the issues reported in Discrepancy l Printed 6/1/98 9 5019 AM Page 3 or 13 l

Northeast Utilities ICAVP DR No. DR-MP3-0580 Millstone Unit 3 Discrepancy Report Report, DR-MP3-0580, do not represent discrepant conditions.

DR-MP3-580 identifies issues with regard the Secondary Containment drawdown times provided in the FSAR, Technical Specifications and design calculations.

FSAR Section 6.2.3.3 The referenced FSAR Section 6.2.3.3, " Safety Evaluation,"

provides a description of the Secondary Containment drawdown requirements. The statements regarding the drawdown times have been reviewed per the CMP Annotation Process and are correct and consistent with the Technical Specifications.

Therefore, no FSAR changes with respect to drawdown times are required.

Amendment No. 87 issued on 12/8/93 changed the Technical Specifications to increase the required drawdown time from 60 seconds to 120 seconds and increased the required negative pressure of 0.4 in. wg.

Amendment 10 issued on 8/24/87 changed the Technical Specifications to increase the emergency diesel startup time from 10 seconds to 11 seconds to avoid declared diesel generator failures for fractions of a second beyond 10 seconds.

The Amendment No.10 changes do not impact the ESF response time requirements. In addition, Technical Specification Bases, Section 4.6.6.2 states that the time to achieve the required negative pressure is 120 seconds, with a loss-of-offsite power coincident with a SIS. Therefore, the 110 seconds from the time of emergency diesel generator breaker closure plus the emergency diesel startup time is correct and consistent with the total drawdown time of 120 seconds.

FSAR Table 1.9-2, SRP 6.5.1.B.5 The statements in this section were compiled for use by the NRC for review during the request for FTOL stage for MP3. FSAR Section 1.9 and the associated tables are considered historical in nature and are not updated. FSARCR 97-MP3-95 was initiated as a result of the CMP FSAR Annotation process to clarify FSAR Section 1.9 as historical. FSARCR was completed on 6/30/97.

SER Section 6.2.3 The MP3 Safety Evaluation Report (NUREG-1031) was issued on 8/2/84 by the NRC. Amendment No. 87 issued on 12/8/93 changed the Technical Specifications to increase the required drawdown time from 60 seconds to 120 seconds and increased the required negative pressure from 0.25 in, wg. to 0.4 in. wg.

Amendment 87 supersedes SER, dated 8/2/84, section 6.2.3 with regard to drawdown time and required vacuum.

Calculation P(B)-843 CR M3-97 2187 was initiated on 7/14/97 to track potential FSAR deficiencies which were kientified during the CMP FSAR annotation process. CR M3-97-2187 corrective action plan required calculation P(B)-843 to be revised. CCN 01 to calculation P(B)-843. Rev. O, was approved on 10/30/97 and Printed 6/1/98 9.59:20 AM Page 4 of 13

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N:rthe=t Utilities ICAVP DR N3. DR-MP3-0580 '

Millstone Unit 3 Discrepancy Report closed CR M3-97-2187. CCN 01 states that the SLCRS is a unique system in that its sizing is not based on rigorous methodology. To do so would require postponing the design until construction is complete and then a rigorous analysis would determine its capacity based on "as constructed" leakage paths, concrete cracks, vendor data, etc. To avoid such delays, secondary containment leakage determination is based on

  • rule of thumb
  • design criteria derived farm previous experience. The criteria adopted on Millstone Unit 3 were three volume changes per day for the containment enclosure and one volume change per day for the balance of the secondary containment. A rigorous computation and system analysis is unwarranted considering the uncertainty of the basic design input. The installed equipment is periodically tested and proven to the defined operating parameters. Therefore, the initial design capacity information in calculation P(B)-843 is considered historical and no additional changes to calculation P(B)-843 are required.

Note that the va ' .ble inlet vane is manually fixed by the vendor -

supplied lever. The vendor drawings 12179-2170.430-002G and 12179-2170.433-004 showing the fan, VIV and lever control.

l Calculation P(B)-1089 i 1) DR-MP3-509 and DR-MP3-580 have identified similar issues l regarding the presentation of P&lD general area exhaust flow l paths and calculation P(B)-1089. The following is the response to DR-MP3-509 which applies to item 1 of calculation P(B)-1089 issues in DR-MP3-580.

DR-MP3-0509 identifies that P&lDs EM-148E, EM-148A, and EM-1528 do not provide the general area exhaust flow paths required to maintain the Secondary Containment under a negative pressure following a LOCA. The format and content of the MP3 P&lDs are established in procedure EDI 30255, "MP3 Piping and instrumentation Diagrams Detailed instructions for Format and Content." EDI 30255 does not require MP3 P&lDs to reflect the actual building arrangement. The P&lDs provide the systems configuration required to maintain the Secondary Containment under a negative pressure following a LOCA. The P&lDs are not required to provide General area exhaust flow rates, therefore, changes to P&lDs EM-148E, EM-148A, EM152B are not required.

l The Secondary Containment is comprised of the containment l enclosure building, the auxiliary building, and sections of the

  • l engineered safety features building, the main steam valve building, and the hydrogen recombiner building. The interior walls of the engineered safety features building, the main steam ,

valve building, and the hydrogen recombiner building which separate the areas contiguous to the containment from the remainder of the buildings serve as the secondary containment boundary. The areas that are not direcuy exhausted by an exhaust duct and registers located within the area are interconnected with adjacent areas that contain exhaust ducts and reaisters. The Secondary Containment Beundaries are <

Pnnted 6/1/96 9 59 20 AM Pa9e 5 of 13

ICAVP DR No. DR-MP3 0580 Northeast Utilities l Millstone unit 3 Discrepancy Report identified on S&W EM-60 series drawings, " Plant Fire Radiation and Pressure Boundaries." The areas of the hydrogen recombiner building that contain the capped off ducts are not j part of the Secondary Containment Boundary The areas of the main steam building and hydrogen recombiner building that are within the Secondary Containment boundary are drawn down through the enclosure building by the SLCRS.

Calculation P(B)-1089," Establish Acceptance Criteria for Air Leakage Through Pipe and Electrical Penetration Seals,"

provides a summary table for the exhaust flow rates for the I applicable areas. The summary table shows the exhaust flow rate for the containment enclosure building as 4950 cfm, the hydrogen recombiner building as 130 cfm and the main steam valve building as 1350 cfm. PalD EM-148E indicates the total exhaust flow from these areas through the 36' X 18' screened opening as 6430 cfm.

As an enhancement, CR M3-97-4557 was initiated to clarify the l air flow rates on all of the MP3 P&lDs. CR M3-97-4557 corrective action requires a review of all air flows and notes on HVAC P&lDs, related Technical Specifications, and FSAR Sections. Based on the evaluation results, the P&lDs will be revised to include clarifying notes or remove air flow information and revise EDI 30225, if required.

2)The containment enclosure was purchased under Specification 2190.371-442. The Specification addresses wind effects on leakage through the enclosure building by assumlag a 22 MPH wind at .0195 cfm/ft2. The wind effects result in a total allowable leakage of 2,830 cfm for the enclosure building. The containment enclosure leakage was not computed in calculation P(B)-1089, as stated on page 9. With the wind effo:ts addressed in the specification, no changes to the calculation are required.

IST 3-93-45 and 3-93-46 1)The heat gain in the MSVB and other areas of the Secondary Containment during the first 120 seconds post LOCA does not have a significant impact or' the test results. The drawdown test is typically performed during refueling outages but has been performed at 100% power. The test results are not significantly different between the testing during refueling outage and the testing during 100% with the MSVB ventilation system isolated. ,

Therefore, the test method and results are satisfactory. l

2) The area the hydrogen recombiner building that is within the I Secondary Containment boundary is shown on the S&W EM-60 series drawings. This area is drawn down through the enclosure building by the SLCRS. SER to Amendment No. 87 concludes that SLCRS (with ABVS)is capa'ule of attaining the required .

negative pressure of 0.4 in. wg. within 120 seconds and that l uiilizing the single measurement location in the auxiliary building I a the 24' 6' level is suitable.  !

Printed 6/1/98 9 5920 AM Page 6 or 13 l

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ICAVP DR No. DR-MP3-0580 Northeast Utilities Millstone Unit 3 Discrepancy Report 3)SLCRS and ABVS airflows are taken once a month to verify fan performance per SP 36141 and SP 3614A. The drawdown test is a functional test of the system and a verification of boundary integrity. There is no requirement to adjust the drawdown time to correspond to the minimum air flow rate.

Technical Specification Bases, Section 4.6.6.2.2 states that since SLCRS fari flow rates are verified to be acceptable on a more frequent basis than the drawdown test surveillance, and by means of previous testing the minimum flow rate is acceptable, verifying a flow rate dedng the drawdown test would not provide an added benefit.

4) Acceptance criteria of these tests were based on a proposed licensing change. The proposed licensing change was amended to a 2 minute drawdown after the tests were completed. The change to the 2 minute drawdown was based cn the test results meeting the required negative pressure of 0.4 in, wg. criteria within 2 minutes.

SER for Amendment No. 87, dated 12/8/93, concludes that SLCRS (ABVS) is capable of attaining the required negative pressure of 0.4 in, wg. within 120 seconds based on the test results.

PTSCR 3-16-94, dated 12/14/94 The last paragraph in DR-MP3-580 describes a proposed revision to TS. This revision to the Technical Specifications is being reviewed by the NRC, therefore, is not part of MP3 license.

Attachments:

CCN 01, Calculation P(B)-843, Rev. O CR M3-97-2187 Second Response (M3-IRF-02108)

NU has concluded that item 3 in Discrepancy Report DR-MP3-0580 has identified a condition not previously discovered by NU which requires correction.

(3) Secondary containment Leakage determination, is based on industry standard design criteria derived from previous experience. The criteria adopted on Millstone Unit 3 were three (3) Volume chenges per day for the Containment Enclosure and one Volume change per day for the balance of the secondary Containment. This criteria was taken from calculation P(B)-843 and used as conceptualinput in calculation P(B)-1089.

Therefore, Calculation P(B)-1089 is considered conceptual to establish pre-construction acceptance criteria for allowable air leakage through di5erent types of pipe and electrical penetration seals. The penetration seals vendor applied a conservative factor of safety to the results of calculation P(B)-1089 and lab teste.d the seals before and after completion of construction under stringent acceptance criteria. Hence, a rigorous revision of such Conceptual calculation and system analysis is unwarranted considering the uncertainty of the basic desian input. NU has Pnnted 6/1/96 9 5920 AM Page 7 of 13

ICAVP DR No. DR-MP3-0580 Northeast Utilities Millstone Unit 3 Discrepancy Report written CR M3-98-1774 to clarify this point. The approved corrective action will initiate a CCN to c,hange the status of calculation P(B)-1089. Rev. 00 to ' Historical Calculation".

NU has concluded that items 2 and 4 of Discrepancy Report DR-MP3-0580 do not represent discrepant conditions.

(2) In-Service Test No. IST 390-014, (copy attached) which is per Surveillance procedure SP 36141.3, was performed successfully on 7/20/90 (at that time the Plant was in Mode 1 of operation). The objective of this test was to verify that the j SLCRS Negative Pressure Verification Test could be performed {

to satisfy its acceptance criteria of producing a negative pressure j equal to or more negative than (-)0.25 inches W.G. within 50 j seconds after a start signal, with flow through the SLCRS system j throttled to 6,800 to 7,200 CFM which is below the flow rate range of 7,600 to 9,800 CFM mandated by Technical Specification.

The successful conclusion of this test resulted in a Tech. Spec.

change to the flow rate acceptance criteria. The objective of NUREG-0800, USNRC Standard Review Plan and associated Branch Technical Position CSB 6-3 B.3, is to provide guidelines for licensing the operation of the Plant. The NRC does not mandate compliance with this Branch Technical Position, nor did it require verification of drawdown by analysis as a condition for licensing in 1985. Nevertheless, as stated above, drawdown at flow rates less than the minimum of the current Technical Specification was verified by test. Monthly flow tests are performed to monitor fan performance in accordance with TS 4.6.6.1. The drawdown test is performed to verify boundary integrity is maintained in accordance with TS 4.6.6.2. There is no requirement to perform flow rate testing during the drawdown test.This item is, therefore, considered non-discrepant.

(4) The objective of CCN 1 is to make calculation P(B)-843 a historical document which has semed its purpose in sizing ite SLCRS drawdown capability using criteria derived from industry practice and previous experience. The system has since been installed, tested, and verified to be adequate for its intended purpose. NUREG-0800, USNRC Standard Review Plan and associated Branch Technical Position CSB 6-3 B.3, provide guidelines for licensing the operation new plants. Therefore, pressure response analysis per NUREG-0800 for a system which has been tested successfully is not required. This item is considered non-discrepant.

The discrepancy reported in item 3 will be corrected post startup per the approved corrective action plan for CR M3-98-1774.

Licensing basis and design basis are not affected; therefore, NU considers this issue Significance Level 4.

Attachments:

CR M3-98-1774 with approved corrective action plan IST 390-014, 7/20/90 l 1  !

Printed 6/1/98 9 s920 AM Page 8 of 13 )

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_________________________________._____.__.______.________U

ICAVP DR No. DR-MP3-0580 Northsast Utilities Millstone Unit 3 Discrepancy Report Previously identined by NU? O Yes In> No Non D6ecrepent Condition?O Yes ($) No Resolution Pend 6ng?O Y= @ No Reedutwunradved?O va @ No l Review initiator: stout, M. D, VT Lead: Nerl. Anthony A VT Mgr: schopfer, Don K IRC Chmn: singh, Anand K Date: 5/29/98 sL Comments: Comments on First Response

1. Agree with NU's response that FSARCR 97-MP3-95 identifies FSAR Table 1.9-2 as historical data and that that SER for Amendment No. 87 supersedes SER dated 8/2/1984.

1

2. The secondary containment drawdown time is a function of the boundary leakage, building volume, heat gain the the building, and the exhaust flow rate. One set of surveillance tests verifies SLCRS and ABVS airflows are within limits and another set of surveillance tests verifies that secondary containment drawdown tims is less than or equal to 120 seconds. Neither of the tests establish the secondary containment boundary leakage as stated in Branch Technical Position CSB 6-3 B.3. Since drawdown tests do not measure the SLCRS and ABVS airflows the ability of the SLCRS and ABVS systems to drawdown the secondary containment within 120 seconds at the lowest Technical Specification allowable airflows is not verified by test nor analysis.

NU's response should address why they do not consider this to be a discrepant condition.

3. Calculation P(B)-1089 determines the allowable leakage rates and exhaust airflows for the areas exhausted by the SLCRS fans.

The results of calculation P(B)-843 are used as input for establishhg the exhaust flow rates. Calculation P(B)-1089 needs to be re-ised to address the use of unverified data from "historit.al" calculation P(B)-843, CCN1.

4. Calculation P(B)-843, CCN 1 states that the secondary containment leakage criteria adopted for Millstone 3 was three volume changes per day for the containment enclosure and one volume change per day for the balance of the secondary containment. The CCN does not provide adequate justification for not performing the pressure response analysis identified in Branch Technical Position CSB 6-3 B.2 and B.4.

Comments on Second Response

References:

1) FSAR Section 6.2.3.3
2) Technical Specification Amendment No. 87 issued 11/4/1993 (revision for surveillance 4.6.6.1.d.3)
3) NU Letter B14669 dated 11/4/1993 A NU Letter B15424 dated 11/9/1995
5) SP 36141.3 SLCRS Negative Pressure Verification - Train B Printed 6/1/98 9:59:20 AM Page 9 or 13

ICAVP DR No. DR-MP3-0580 Northeast Utilities l

Millstone Unit 3 Discrepancy Report test results dated 5/30/1995 l 6) SP 36141.1 SLCRS Operability Test - Train B test results dated 1/23/1998

7) IST 390-014 test results dated 7/20/1990
8) P&lD EM-148A-24
9) P&lD EM-148B-15
10) P&lD EM-148E-12 l 11) Technical Specification bases section 3/4.6.6.1
12) Technical Specification bases section 3/4.6.6.2
13) Technical Specification bases section 3/4.7.9
14) SLCRS Negative Pressure Verification - Train B test results dat*d %/4/95 (retest for ACR 005188)

Disagree with NU's response.

The run #1 (A Train) results of IST 390-014 show that the Main Steam Valve Building (MSVB) differential pressure is -0.41 iwg l

and Aux. Bldg el 24'-6* differential pressure is > -0.5 iwg (off scale) at 50 seconds. The run #3 (B Train) results show that the MSVB differential pressure is -0.11 iwg and Aux. Bldg el 24'-6" differential pressure is > -0.5 iwg (off scale) at 50 seconds. As the MSVB differential pressure is more representative of the containment enclosure differential pressure, the B Train drawdown test does not support the conclusion that at a SLCRS airflow of 7200 cfm that the .25 iwg differential pressure within 50 seconds (acceptance criteria in effect when test was run) was met. The results of this test also do not support the conclusion that the current drawdown requirement of -0.40 iwg within 120 seconds could be met with the minimum SLCRS airflow of 7600 cfm.

The results of SP36141.3 SLCRS Negative Pressure Verification -

Train 8 test conducted on 5/30/95 show an Aux Building differential pressure of -0.25 iwg at 50 seconds and -0.425 iwg at 120 seconds. The system airflows for this test are not known as they were not measured. If they are comparable to the 8811 scfm measured on 1/23/98 during performance of SP 36141.1 SLCRS Operability Test - Train B 11 is not apparent that the 120 second drawdown time could be achieved with the Technical Specification 4.6.6.1.a minimum SLCRS airflow of 7600 cfm.

Note 2 on P&lD EM-148E-12 states that SLCRS operability is demonstrated by Technical specification surveillance flows of 7,600 to 9,800 cfm.

The drawdown time is a function of the secondary containment boundary leakage and the SLCRS and ABVS airflow rates. NU Letter B155424 dated November 9,1995 responds to a NRC Staff question during a October 4,1995 conference call as to why NNECO was not specifying a maximum allowable flow rate in the Secondary Containment drawdown surveillance requirement (i.e.,

Surveillance Requirement 4.6.6.1.d.3 which is being relocated to Specification 3.6.6.2, Secondary containment). NU's response in this letter states in the 3rd paragraph on page 2 "The SLCRS syste m and fan sizing was based on an estimated infiltration rate.

The fan flow rates are verified within a minimum and maximum on a monthly basis. Initial testina verified that the drawdown Prtnted 6/1/90 9.50 20 AM Page 10 of 13

ICAVP DR N9. DR-MP3-0580 j Northeast Utilities Millstone Unk 3 Discrepancy Report l criteria was met at the lowest acceptable flow rate. Surveillance Requirement 3.6.6.12 of the new standard Technical 1 Specification (NUREG-1431) requires that the drawdown criterion  !

be met while not exceeding a maximum flow rate. It is assumed that the purpose of this flow limit is to ensure t'lat adequate attention is given to maintaining the SLCRS (secondary containment) boundary integrity and not using excess system capacity to offset boundary degradation." The 4th paragraph on page 2 states "The SLCRS system was designed with minimal l l

margin; therefore it does not have excess capacity that can be substituted for boundary integrity. Additionally, SI.CRS fan flow rates are verified to be acceptable on a more frequent basis than

]

the drawdown test surveillance. Previous testing of the minimum l

flow rate is acceptable, thus verifying a flow rate during the I drawdown test would not provide an added benefit. Historical SLCRS flow measurements show a lack of repeatability associated with the inaccuracies of air flow measurement. As a result, the more reliable verification of system performance is the actual negative pressure generated by the drawdown test and a measured flow rate would add little benefit."

NU letter B155424 does not address the impact that the Charging Pump and Component Cooling Water Pump Area fans (3HVR*FN13A/B and 3HVR*FN14A/B) and Auxiliary Building i

Ventilation Filter exhaust fans (3HVR*FNSA/B) have on Secondary Containment drawdown time. Fans 3HVR*FN6A/B,

  • FN13A/B, and *FN14A/B operate in conjunction with SLCRS exhaust fans 3HVR*FN12A/B to drawdown the secondary containment. The amount of outside air supplied by fan 3HVR*FN14A/B is seasonally adjusted by repositioning dampers 3HVR*DMP4 and 3HVR*DMP32 twice a year per note 17 on P&lD EM-148A. The summer and winter mode positions are marked on the dampers used to change the system from summer to winter mode. The net exhaust (outside air supply - exhaust) airflow used to assist the SLCRS in the drawdown of the secondary containment is not measured on a regular basis as part of a Technical Specification Surveillance. Changes in this net exhaust airflow could mask degradation of secondary containment if the airflow is not known during the drawdown test.

Technical Specification surveillance requirement 4.6.6.2.2 states "At least once each refueling interval, verify that each Supplementary Leak Collection and Release System produces a negative pressure of greater than or equal to 0.4 inch water gauge in the Auxiliary Building at 24'-6" elevation within 120 seconds after a start signal."

Technical Specification surveillance requirement 4.6.6.1 requires a SLCRS airflow rate between 7600 cfm to 9800 cfm is verified at least once every 31 days on a staggered test basis.

Therefore, measurement of the SLCRS & ABVS airflow rates during drawdown time surveillance testing and evaluation of the results is necessary to verify that the drawdown time stated in FSAR Section 6.2.3.3 and used in the offsite dose analysis can be met at the lowest desian SLCRS airflow rate of 7600 cfm.

PrirWed 6/1/96 9.s0 2o AM Page 11 or 13

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ICAVP DR No. DR-MP3-0580 Northeast Utilities Millstone Unit 3 Discrepancy Report  :

Measurement of the outside air intake and exhaust airflows associated with auxiliary building fans 3HVR*FN06A/B, 3HVR*FN13A/B, and 3HVR*FN14A/B is also needed to verify that variation in the auxiliary building ventilation system exhuast air to outdoor air differential airfow (resulting from annual summer / winter mode changeover) do not mask degradation of secondary containment integrity.

The DR is unresolved.

1 This DR is being reissued to clarify the issues that are confirmed discrepancies.

We concur with NU that the current secondary containment drawdown test, which does not specify system airflows, was accepted by the NRC when Amendment 87 of the Technical Specification was issued. As NU is in compliance with the technical specification this is not a discrepant condition.

CCN 1 to calculation P(B)-843 was issued as part of the corrective action of CR M3-97 2187. CCN 01 states "SCRS is a uniqu.; system in that its sizing is not based on rigorous methodology. To do so would require postponing the design until construction is complete and then a rigorous analysis would determine its capacity based on 'as constructed' leakage paths, concrete cracks, vendor data, etc. To avoid such delays, secondary containment leakage determination is based on ' rule of thumb

  • design criteria derived form previous experience. The criteria adopted on Millstone Unit 3 were three volume changes per day for the containment enclosure and one volume change per day for the balance of the secondary containment. A rigorous computation and system analysis is unwarranted considering the uncertainty of the basic design input. The installed equipment is periodically tested and proven to the defined operating parameters. Therefore, this calculation is historical in nature" The corrective action of CR M3-98-1774 states
  • Review MP3 calculation P(B)-1089 ' Establish Acceptance Criteria for Air Leakage Through Pipe and Electrical Penetration Seats' and calc.

P(B)-843 ' Supplemental Leak Collection and Release System'.

Reverify that the data contained within calc. P(B)-1089 is historical in nature, add justification addressing inputs taken from calc. P(B)-843 and revise as such with a reference tie in the body of the calculation, as well as in the Calculation Tracking Program input sheet to calc. P(B)-843." The deferral justification for CR M3-98-1774 states "The revision to calculation P(B)-1089 will provide justification that it is an historical calc. In nature and provide a reference and program tie to calc. P(B)-843. Both calculation were initial conceptual plant design calculations and can be considered historicalin naure. The integrity of the Secondary Containment and penetration bypass leakage is periodically verified by Tech Spec. Surveillance's and inservice inspections.

The information contained in calculation P(B)-1089 does not affect any plant procedure, the operation of any plant system or eauipment. affect Tech Spec requirements or system desian Pnnled 6/1/98 9.59 21 AM Page 12 or 13

ICAVP DR No. DR-MP3-0580 Northeast Utilities Millstone Unit 3 Discrepancy Report basis or operation as described in the FSAR."

Based on the periodic surveillance tests meeting the technical specification requirements, the corrective actions for calculations P(B)-843 and P(B)-1089 resolve level 4 discrepancies.

However, we do not concur that the Technical Specification surveillance requirements are adequate to ensure that secondary containment boundary leakage is within design limits and the SLCRS in conjunction with the ABVS system will meet its drawdown time requirements under accident conditions. This issue will be forwarded to the NRC.

I Printed 6/1/96 9.59:21 AM p ,33 g g3

f ICAVP DR No. DR-MP3-1009 Northeast Utilities Millstone Unit 3 Discrepancy Report Review Group: Programmatic DR RESOLUTION ACCEPTED Rev6ew Element: CorrectNe Action Procese ,

Discipline: I & C Deeagn O vee D6screpancy Type: CorrectNe Action implementeten

@) No

~

l SystemProcess: SWP NRC Significance level: 4 Date faxed to NU:

Dete Publ6shed: 2/7/96 D6ecrepency: Inadequate implementation Documentation

Description:

Unresolved item Report (UIR) 432 Closure Request documents that an " engineering review" (Material Equipment Parts List (MEPL) evaluation MP3-CD-1071) was performed to disposition Non Conformance Report (NCR) 395-065; however, this

" engineering review" (MEPL evaluation MP3-CD-1071) was not included in the UlR 432 closure package.

Review Ve86d invalid Needed Date 1'3o'S8 inittetor: Dombrowsid, Jim O O O O O 3o'S8 VT Leed: Ryan. Thomas J O VT Mgr: Schopfer, Don K G O O 2/2/98 IRC Chmn: Singh, Anand K B D D 2/3/98 Deie:

INVALID:

Dete: 5/29/98 RESOLUTION:

NU's First Response NU has concluded that Discrepancy Report, DR-MP3-1009, has identified a condition not previously discovered by NU which requires correction. This discrepancy meets the criteria specified in NRC letter B16901 and 17010. It has been screened per U3 PI-20 criteria and found to have no operability or deportability concems and meets the Unit 3 deferral criteria. CR M3-98-1143 has been written to develop and track resolution of this item per RP-4.

NU's Second Response Background-S & l's Considers the NU response stated in M2-IRF-01914 to Discrepancy Report DR-MP3-1009 unacceptable. S & L restates the discrepancy as follows:

This ACR was identified as a " Start-up" document. Unless a specific reason acceptably dispositions this ACR as to why verification of completion will be delayed till after plant start-up, this DR resolution is unacceptable.

Disposition:

NU has concluded that the issue reported in DR-MP3-01009 has identified a NON-DlSCREPANT condition.Further investigation Pnnted 6/1/98 9.s9 51 AM Page 1 of 4

Northeast Utilities ICAVP DR No. DR-MP3-1009 Millstone Unit 3 Discrepancy Report has determined that the closure package is adequate. NCR 3 0065 identified and resolved the condition tracked by UIR 432, and is contained in the UIR 432 Closure Package. MEPL MP3-CD-1071 is referenced by NCR 3-95-0065, but is not considered part of the NCR. MEPL MP3-CD-1071 is being provided.

Significance level criteria do not apply here as this is a non-discrepant condition.

Conclusion:

NU has concluded that the issue reported in DR-MP3-01009 has identified a NON-DISCREPANT condition.Further investigation has determined that the closure package is adequate. NCR 3 0065 identified and resolved the condition tracked by UIR 432, and is contained in the UIR 432 Closure Package. MEPL MP3-CD-1071 is referenced by NCR 3-95-0065, but is not considered part of the NCR. MEPL MP3-CD-1071 is being provided.

Significance level criteria do not apply here as this is a non-discrepant condition.

Attachments: DNCR 3-95-00650 DMEPL MP3-CD-1071 NU's Supplemental Response:

Disposition:

NU has concluded that this issue reported in DR-MP3-01009 has identified a CONFIRMED SIGNIFICANCE LEVEL 4 condition which requires correction. This discrepancy meets the criteria specified in NRC letter B16901 and 17010. It has been screened per U3 Pi-20 criteria and found to have no operability or deportability concems and meets the Unit 3 deferral criteria. This item meets the deferral criteria of section 1.3.2.e of U3 PI-20.

CR M3-98-1143 has been written to correct the original item post startup. CR M3-98-1143 has been closed to BIN CR M3 0135. CR M3 98-2631 has been written to identify that the disposition of NCR 395-065 does not clearly state the bases for the decision, and to correct this post startup.

MEPL evaluation MP3-CD-1071 identified several instruments installed on the Service Water system that were designated as nonQA but were connected to the system through common l tubing with safety related instruments. The concem was that a postulated failure of the nonQA instrument to maintain its system pressure boundary could render the safety related instrument as unable to perform their safety function. The original NCR disposition indicated that the instruments would be upgraded to QA, UlR 432 documented this action as startup related, however a subsequent ADMIN Disposition declared the condition as non-discrepant based upon engineering review but did not provide any basis for that disposition. UIR 432 was closed based upon the ADMIN disposition on the NCR.

The installation proaram implemented at MP3 established two PrWed 6/1/98 9 59.51 AM Page 2 or 4 l

l

Northeast Utilities ICAVP DR No. DR-MP3-1009 Millstone Unit 3 Discrepancy Report installation categories. Group A installations were those instruments connected to safety related process piping or equipment regardless of whether or not the instrument performed a safety r6ted function. Group B installations connect non-safety re.Jaled instrumentation to non-safety related processes.

Group A installations are designated as safety class 2, QA, seismic, and meet the design and material requirements of ASME lil, subsection NC. The original procurement specifications for instruments such as those identified in the MEPL purchased instruments as either QA Cat 1 or QA Cat 2 under the Stone & Webster QA program. The seismic acceptability or qualification of the instruments was documented via a qualification test report through the procurement specification or the instruments were evaluated for seismic pressure boundary integrity through calculation by the engineering department. The seismic acceptability of the instruments is not based upon the QA, or nonQA, MEPL designation established for the purposes of future procurement and replacement of the instruments but is instead based upon how the instruments will be installed in the plant, i.e., as Group A. Therefore, the ADMIN Disposition of NCR 395-065 is correct and the UIR is not a startup related issue however the basis for the NCR disposition does not adequately document the above described installation basis and will be corrected

Conclusion:

NU has concluded that this issue reported in DR-MP3-01009 has identified a CONFIRMED SIGNIFICANCE LEVEL 4 condition which requires correction. This discrepancy meets the criteria specified in NRC letter B16901 and 17010. It has been screened per U3 PI-20 criteria and found to have no operability or deportability concems and meets the Unit 3 defval criteria. This item meets the deferral criteria of section 1.3.2.e of U3 PI-20.

CR M3-98-1143 has been written to correct the originalitem post startup. CR M3-98-1143 has been closed to BIN CR M3 0135. CR M3-98-2631 has been written to identify that the disposition of NCR 395-065 does not clearly state the bases for the decision, and to correct this post startup.

Attachments:0CR M3-98-2631 Previously identified by NU7 O Yes ie) No NonDiscrepentCondsuon?O Yes (9) No ResolutionPending?O Yes v No Resoiution unre.oived70 Yo. ce) No Review initiator: sheppard. R. P.

VT Lead: Ryan, Thomas J VT Mgr: schopfer, Don K IRC Chmn: singh, Anand K Date: 5/29/98 SL comments:

S&L's Comments to NU's First Response Printed 64/98 9 s9 52 AM Page 3 or 4

A Northeast Utilities ICAVP DR No. DR MP3-1009 Millstone unit a Discrepancy Report This ACR was identified as a " Start-up" document. Unless a specific reason acceptably dispositions this ACR as to why verification of completion will be delayed till after plant start-up, this DR resolution is unacceptable.

S&L's Comments to NU's Second Response NU's Response is unacceptable.

NU has not provided a copy of the " engineering review" documentation as noted in the NCR 395-065 ADMIN Disposition.

This " engineering review" provided the justification that the non-conforming conditions were determined not to be valid; consequently, justifying the NCR closure as Admin and not requireing any field changes. This " engineering review" was requested in this DR but not received .

NU has not indentified what actions they intend to take after startup per CR M3-98-1143. Note: CR M3-98-1143 references

" Historical Record Cleanup".

S&L's Final Comments NU's Supplemental Response is acceptable.

l Printed 6/1/96 9.50.52 AM Page 4 of 4 L__- .. . . ..

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