ML20213G968
| ML20213G968 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/13/1987 |
| From: | Jaffe D Office of Nuclear Reactor Regulation |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8705190067 | |
| Download: ML20213G968 (10) | |
Text
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o May 13,1987 MEMORANDUM FOR:
John Stolz, Director 3"
t> ~ 3 3 la Project Directorate I-4 Division of Reactor Projects I/II FROM:
D. H. Jaffe, Project Manager Project-Directorate I-4 Division of Reactor Projects I/II
SUBJECT:
MILLSTONE UNIT 2 SYSTEMS INSPECTIONS REPORT 87-01, DIESEL GENERATORS During the period from April 6 to April 10, 1987, I was at Millstone Unit 2 for the purpose of inspecting the diesel generators and associated 1
auxiliaries. The enclosed presents my observations and will be forwarded to Resident Inspector for inclusion in the next inspection report.
/s/
D. H. Jaffe, Project Manager Project Directorate I-4 Division of Reactor Projects I/II DISTRIBtITION Docket or Central? file 4
NRC & Local PDRs ""
PDI-4 Reading J. Stolz B. Boger D. Jaffe OGC-Bethesda E. Jordan J. Partlow NRC Participants ACRS(10) cc: Licensee list O
e:sw J
z 5/[t/87 5
/87 5/((/
B705190067 870513 PDR ADOCK 05000336 G
W Mr. John F. Opeka Millstone Nuclear Power _ Station Northeast Nuclear Energy Company Unit No. ?
cc:
Gerald Garfield, Esq.
Mr. Wayne D. Romberg Day, Berry & Howard Superintendent Counselors at Law Millstone Nuclear Power Station City Place P. O. Box 128 Hartford, Connecticut 06103-3499 Waterford, Connecticut 06385 Regional Administrator, Region I Mr. Edward J. Mroczka U.S. Nuclear Regulatory Commission Vice President, Nuclear Operations Office of Executive Director for Northeast Nuclear Energy Company Operations P. O. Box 270 631 Park Avenue Hartford, Connecticut 06141-0270 King of Prussia, Pennsylvania 19406 Mr. Charles Brinkman, Manager Washington Nuclear Operations C-E Power Systems Combustion Engineering, Inc.
7910 Woodmont Avenue Bethesda, Maryland 20814 Mr. Lawrence Bettencourt, First Selectman Town of Waterford Hall of Records - 200 Bostor. Post Road Waterford, Connecticut 06385 Northeast Utilities Service Company ATTN: Mr. Richard R. Laudenat, Manager Generation Facilities Licensing Post Office Box 270 Hartford, Connecticut 06141-0270 Kevin McCarthy, Director Radiation Control Unit Department of Environmental Protection State Office Building Hartford, Connecticut 06106 Mr. Theodore Rebelowski U.S. NRC P. O. Box 615 Waterford, Connecticut 06385-0615 Office of Policy & Management ATTN: Under Secretary Energy Division 80 Washington Street Hartford, Connecticut 06106 i
Enclosure Millstone Unit 2 Systems Inspection Report 87-01 Diesel Generators Introduction Emergency AC power for Millstone Unit 2 is supplied by two,12 cylinder, opposed piston, turbocharged. Fairbanks Morse,; Diesel Generator (DG) Units, Model No. 3800TD8-1/8. The continuous power rating for each unit is 2750 KW.
Each DG is mounted on a skid with the following auxiliaries:
(1) lube oil, (2) jacket cooling, and (3) air cooling.
Cooling water for the DG auxiliaries is supplied by the service water (salt' water) system.
Fuel oil is stored in an underground, 25,000 gal, tank and transferred to two 12,000 gal, tanks (one for each DG) located in separate rooms above the DGs. Each DG has an air starting system with a 480v (vital bus) AC compressor, a back up DC compressor and two air storage tanks. Each DG, its ' piping, and its auxiliaries (including local control panels) is housed in its own Class I room within the auxiliary building. Access between these adjacent rooms is via a security and a water-tight door. Ventiliation, emergency lighting and fire protection are provided; i
for each DG room, During standby conditions, the DGs are provided with circulating, warmed (jacket cooling) water and with warmed lube oil.
Prior to starting for routine surveillance, the control room operator manually operates a prelube pump. Under emergency conditions (on loss of normal power) the OGs automatically start (without prelube) and automatically accept emergency loads.
Inspection i
The following areas associated with the DGs were inspected:
1.
Documentation 2.
Housekeeping i
--,,n,,_--n,..
,,-,.n---
2 3.
Maintenance (routine and preventive) 4 Operations 5.
Control Room 6.
Compliance with Technical Specifications Documentation The description of the DGs in the FSAR, Sec'cfon 8.3, was compared against field observations to determine the accuracy of the FSAR for this area.
It ivas found ti.at FSAR Figure 8.3-5 does not show the air start filters and dryers that were installed between the air start compressors and air tanks.
These filters and dryers are described in FSAR Section 8.3.2.2.
In addition, the recent elimination of the Safety Injection Actuation Signal (SIAS) start 1
signal for the DGs should be reflected in the next FSAR update. The remainder of the FSAR text, figures, and tables appeared to be accurate.
Zeusekeeping i
The following areas were inspected with regard to housekeeping:
e DG Room A t
e DG Room B e
DG Supply Tank Rooms e
DG Storage Tank Area All areas inspected were clean and notably free of trash, tools and unnecessary combustibles. The DGs showed signs of the minor fu(I oil leakage t
that is common to these engines. The following was noted:
e Local control panels C38 and C39 did not have their identifying numbers shown.
'e Several valve identification tags were missing.
e The "A" DG fuel oil duplex filter showed excessive leakage (referred to maintenance).
3 A bulb of the "A" DG control panel Synchroscope was broken (referred e
to maintenance).
Marker pen was used on "A'" and "B" OG control panels (C38 and C391.
e This marking should be removed and replaced with a mimic if necessary.
Overall, the housekeeping situation was very good in the DG areas described above.
Maintenance The preventive and identified maintenance system for the DGs and auxiliaries was audited. All instrumentation associated with the DGs is covered by a single procedure, IC-2434, which requires calibration on an 18 month
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frequency. Each instrument loop (indicator, sensor, transmitter combination) has an individual folder containing calibration data. A sample file was reviewed, L-7004 (diesel fuel rD storage tank level) and was found to be complete and up-to-date. All instruments observed in the DG rooms had current calibration tags. Outstanding mechanical maintenance requests were reviewed and found to be minor in nature with the longest outstanding item being four months old. Both routine and preventive maintenance items are controlled by the Production Maintenance Management System (PMMS) which is a computerized system.
Two identified maintenance tasks for the "A" DG were observed, the repair of a leaking plug in an air start tank and repair of the identified, leaking, duplex fuel oil filter. Both items were controlled by a complete work package l
from PPNS. Maintenance personnel appeared to be well trained and completed their assigned tasks expeditously; good housekeeping techniques were observed.
l Operations Following maintenance on the "A" DG, the licensee demonstrated operability of the "A" DG by performing Procedure OP 2346A, " Emergency Diesel Generators",
l i
4 including valve alignment and the prestart checklist (OPS Form 2346A-2). One item on the prestart checklist, Lube Oil Sump Level (Dipstick) was inadequately verified. The sump level is checked by verifying that the level is "Approximately 3 above Full Mark".
It was observed that the operator found a level of approximately 6" above the full mark but did not note an unusual condition. Conversations with the licensee indicated that they were having difficulty establishing an acceptance criterion for normal sump level.
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Subsequent conversations with Fairbanks Morse indicated that sump level should be checked with the DG running; Procedure 2346A should be changed accordingly.
Following observations of the prestart check list perfonnance, the starf.ing and loading of the "A" DG was observed from the Control Room. Procedure OP 2346A was completed with a minor problem at Step 7.2.12 which requires the DG output breaker to be closed resulting in the DG being " paralleled" w'ith the
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grid. Step 7.2.11 requires the operator to establish a slow rotation rai:e of the Synchroscope (in the fast direction) prior to closing the output breakers in Step 7.2.12 when the Synchroscope " needle passes 11 o' clock". Step 7.2.12 had to be repeated a number of times in order to close the output breakers.
During an emergency situation, the DGs would start automatically on loss of power e.d the output breakers would automatically close on a deenergized bus;
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thus, a problem with synchronization would not exist. The licensee intends to pursue the problem with Step 7.2.12.
Control Room The main control and alarm functions for the DGs are located in the Control Room on panel C08. As noted previously, panel numbers are not displayed. The alanns associated with the DGs are described in the Control Room Annunicator Book (CRAB) but the required diagnostic / remedial actions are contained in Procedure OP 2346A, Section 8.
The contents of OP 2346A, Section 8, and the CRAB were compared with the alarm windows on panel C08. This process resulted in the identification of a minor error in OP 2346A, Section 8.12 (the SIAS START function was removed from the m--
5 DG but was not deleted from OP 2346A) and'a minor error in the CRAB (the
" Diesel Gen. 13U, BRKR, CLOSING CKT. BLOCKED" alarm window was not correctly identified in the CRAB). Both errors were corrected by the licensee.
Procedure OP 2346A was also reviewed against the P& ids to confirm consistency I
with regard to alarm initiating devices.
Complian'ce with Technical Specifications (TS)
Table 1 shows the procedures which the licensee uses to comply with the TS Surveillance Requirements for the DGs. The procedures referenced in Table 1 were reviewed to assure that the contents of the procedures would provide compliance with the TS. The following was noted e
SP 2735, " Diesel Inspection", references an incorrect TS.
Section 3.1 references Surveillance Requirement 4.8.2.2.3.B,.1
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which should actually be 4.8.1.1.2.C.1.
e SP 2613E, " Diesel Generator Fuel Oil Sampling", references an incorrect standard for fuel oil properties. The acceptance criteria for SP 2613E references ASTM-D975-78 while TS 4.8.1.1.2 requires the use ASTM-D975-74. A comparison of ASTM-D975-78 and ASTM-D975-74
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indicates that there are no substantial differences. While use of ;
the incorrect standard represents non compliance with TS4.8.1.1.2, 1
the non compliance is not judged to be serious.
A sample of completed procedures, referenced in Table 1, was reviewed in order to confim that the correct surveillance intervals were being observed.
With the exception as noted above, the licensee is in compliance with the TS for Diesel Generator surveillance.
Conclusions The licensee should assure that the FSAR is kept up-to-date.
For the areas inspected, housekeeping and maintenance were very good. The licensee should clean control panels C38 and C39 and these panels should be prominently
6 Table 1 Diesel Generator Technical Specification Compliance Technical Specification Procedure 4.8.1.1.2 Each diesel generator shall be demon-SP 2613B, Rev. 7, Change.1 " Facility II strated OPERABLE:
Diesel Generator Op. Test" a.
At least once per 31 days on a STAGGERED TEST BASIS by:
1.
Verifying the fuel level in the fuel oil supply tank.
2.
Verifying the diesel starts from ambient condition and accelerates to)< 90% of rated speed and to)>97%
ofratedvoltageinf20 seconds.
3.
Verifying the generator is synchro-nized, loaded to)>1300 kw in 4 60 seconds, and operates for 3>60 min-utes.
b.
At least once per 92 days by verifying SP 2613E, Rev. 3, " Diesel Generator that a sample of diesel fuel from each Fuel Oil Sampling" of the three fuel oil storage tanks, obtained in accordance with ASTM-D270-65, is within the acceptable limits specified
.t in Table 1 of ASTM D975-74 when checked
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for viscosity, water and sediment.
c.
At least once per 18 months during shut-down by:
1.
Subjecting the diesel to an inspec-SP 2735, Rev. 2, " Diesel Inspection" tion in accordance with procedures prepared in conjunction with its manufacturer's recommendations for this class of standby service.
2.
Verifying that the autcmatic time SP 2613C, Rev. 9. " Engineered Safety delay sequencer is OPEDABLE with Safety Feature Systems (ESF) Integrated the following settings:
Test"
7 Table 1 (cont'd)
Sequence Time After Closing of Diesel' Generator
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Output Breaker (Secondsl Step
__ Minimum Maximum 1 (T )
1.5 Z.2 2(
)
T + 5.5 8.4 3(
)
T + 5.5 14.6 4(
)
T + 5.5 20.8 3.
Verifying the generator capability to SP 2613C, Rev. 9 reject a load of? 250 kw and maintain voltage at 4160 +500 volts and frequency at 60 + 3 Hz.
4.
Verifying the generator capability to SP 2613C, Rev. 9 reject a load of 1300 kw without exceed-ing the overspeed trip setpoint.
5.
Simulating a loss of offsite power in SP 2613C, Rev. 9 conjunction with a safety injection actuation signal, and:
a)
Verifying deenergization of the SP 2613C, Rev. 9 emergency busses and load shedding from the emergency busses.
b)
Verifying the diesel starts from SP 2613C, Rev. 9 ambient condition on the autostart signal, energizes the emergency
.t busses with permanently connected loads, energizes the auto-connected emergency loads through the load secuencer and operates for? S min-utes while its generator is loaded with the energency loads.
c)
Verifying that on the safety in-SP 2613C, Rev. 9 jection actuation signal, all diesel generator trips, except engine overspeed, generator differ-ential current, voltage restraint overcurrent, and low lube oil pressure (2 out of 3) are auto-matica11y bypassed.
6.
Verifying the diesel generator operates SP 2613C, Rev 9 for>60 minutes while loaded to? 2750 kw.
7.
Verifying that the auto-connected loads SP 2613C, Rev. 9 I
to each diesel generator do not exceed the 2000 hour0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> rating of 3000 kw.
8 labeled. The licensee should confirm that all valves are tagged.
- Finally, the licensee should develop proper acceptance criteria for diesel sump level.
With regard to diesel operation, the licensee should resolve the problem associated with closure of the DG output breaker under paralleling conditions.
In the area of Technical Specifications the licensee is in compliance with the surveillance requirements except for fuel oil sampling which should be addressed.
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