ML20002B539
| ML20002B539 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 11/17/1980 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20002B537 | List: |
| References | |
| NUDOCS 8012110831 | |
| Download: ML20002B539 (9) | |
Text
O
!p# 4Gy o
UNITED STATES
[
i NUCLEAR REGULATORY COMMISSION
\\\\
f.
f WASHINGTON. D. C. 20555 f /'? M [ f 8
a-g s.
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT N0. 53 TO FACILITY OPERATING LICENSE NO. DPR-40 OMAHA PUBLIC POWER DISTRICT FORT CALHOUN STATION, UNIT NO.1 DOCKET NO. 50-285 Introduction On February 14, 1978 the NRC issued Amendment No. 38 to the Fort Calhoun Station, Unit 1 Operating License which incorporated into the Facility Technical Specifications the elements of the then existing fire protection systems and administrative controls.
Following further evaluation of the fire protection program at the Fort Calhoun Station, the staff issued Amendment No. 40 on August 23, 1978, which incorporated a license condition related to the completion and implementation of fire protection modifications.
Subsequent to August 23, 1978, the licensee has submitted additional infonna-tion and proposed revisions to the fire protection program. The staff has reviewed this additional information and has made the following findings which are presented in the order of, and with the same numerical designations as, the itemi listed in tne August 23, 1979 SER. This SER supplements the August 23, 1978 SER.
Discussion and Evaluation Item 3.1.4 - Fuel Tank for Diesel Driven Fire Pumo SER Section 3.1.4 indicates that a modification will be made to prevent structural steel framing in the vicinity of the fuel storage tank, supplying the diesel engine-driven fire water pump, from being damaged by a fire at the tank.
By letter dated August 23, 1978, the licensee proposed to provide a reinforced concrete block enclosure around the diesel fuel tank, and fill the space between the tank and the enclosure walls with sand and/or limestone.
The proposed modificacion effectively buries the tank and eliminates it as a possible fire hazard. However, the proposed arrangement of liquid level indicator and drain line does not sufficiently eliminate the possibility of a diesel fuel leak which could present a fire hazard to the intake structure. Therefore, the staff recommends the following modifications or equivalent alternatives be incorporated:
8012110 F3/
, 1.
The drain line should be terminated above the enclosure without penetrating the enclosure wall.
2.
The existing " sight glass" level ir dicator on top of the tank should be used instead of the proposed level indicator.
Subsequently, by letter dated May 23, 1979, the licensee provided a revised plan which includes concrete wing walls to protect the drain line and the sight glass.
The staff finds this modification to be acceptable and considers this item to be closed.
l Item 3.1.12 - Fire Detectors SER Section 3.1.12 indicates that the licensee will install fire detectors in the two safety injection and containment spray pump rooms on elevation 971' of the auxiliary building.
By letter dated January 8, 1979, the licensee provided a Fire Detector Analysis which showed the approximate locations of the three ionization type smoke detectors proposed to be installed in each of these rooms.
The proposed modifications appear to be satisfactory, with one exception.
The detectors to be installed in safety injection and containment spray pump room number 2 (Fire Area 2) are shown on drawing no.13007-SK-3 to be upstream of a cable tray in the room.
Because of the postulated air flow patterns in this room, a fire in these cables may not be readily detected by these detectors. We had previously recommended that unless there were additional considerations not included in the licensee's analysis, a better location for the two detectors between column lines 6E and 8A would be west of the cable tray shown on the drawing.
Subsequently, by letter dated July 9,1979, the licensee indicated that the cable tray of concern contains two nonsafety-related control cables while the cable tray on the east side of the room contains 28 control cables (of which 24 are safety-related) and six power cables (of which 4 are safety-related). The selected locations of the detectors are above the safety injection pumps where the exposure fire hazard to the cables is greatest. Therefore, the licensee concluded that the selected detector locations are optimum for the fire hazards in the room.
We accept the licensee's position and therefore, find this item satisfactory and consider it to be closed.
Items 3.1.15 and 3.2.4 - Cable Separation SER Sections 3.1.15 and 3.2.4 indicate that the licensee will:
.v
- 1) Apply flame retardant coatings to cables or install fire barriers in areas where redundant trains of safety-related cables do not meet the separation requirements, or where nonsafety-related cables are interposed between redundant divisions of safetr vlated cables,
- 2) Describe the minimum separation between redundant cables, including the presence of interposing combustibles, and propose modifications to preserve the safe shutdown capability of the plant in all areas in which redundant safe shutdown related cables are located.
In the Fire Protection SER, the concern was that the separation of redundant trains of safety-related cables in several areas of the plant was not sufficient to assure that one train of safe-shutdown system cables would remain functional after a fire.
By letters dated September 29,1978, July 9,1979, and May 20, 1980, the licensee provided the results of his analysis. The licensee identified the following eight areas which contained redundant safe shutdown systems:
Cable Tray and Personnel Corridor Area l
Intake Structure Compressor Area Electrical Penetration Area, Basement Floor Electrical Penetration Area, Ground Floor Switchgear Area Cable Spreading Room Control, Room Complex The licensee proposed to provide alternate shutdown capability for the control room and cable spreading room areas.
The licensee also proposed to erect a three-hour fire rated wall to separate the redundant switchgear trains in the switchgear area, and to either protect or reroute interposing cables. For the cable tray and personnel corridor area and the intake structure, the licensee proposed to provide a 3-hour rated enclosure or noncombustible barrier to separate one division of safe shutdown cables from redundant divisions.
For the compressors and electrical penetration areas, the licensee proposed to provide barriers which would meet the requirements of IEEE 384.
We find that the licensee's commitments to provide alternate shutdown capability for the control room and cable spreading room areas is adequate for those areas. We also find that the commitment to provide a 3-hour wall to separate redundant switchgear in the switchgear room is acceptable.
However, the licensee has not demonstrated that the proposed protection for redundant safe shutdown cables, which pass through the areas of the switchgear room and the remainder of the areas identified above, will be adequate to ensure that at least one means of achieving safe shutdown conditions will survive a postulated fire in these areas.
The proposed 3-hour barriers are of construction which has not been tested to show that, when applied as a wrap around of electrical cables, circuit integrity can be maintained in the protected cables for a 3-hour ASTM E-119 fire. The IEEE 384 "Sarriers" are in reality only heat shield and do not provide adequate protection from exposure fires.
To meet our fire protection guidelines, alternate shutdown capability should be provided when safe shutdown cannot be ensured by barriers and detection and suppression systems because of the exposure of redundant safe shutdown equipment, cabling, or components in a single fire area, to an exposure fire, or fire suppression activities, or rupture or inadequate operation of fire suppression systems.
To meet Section III, Paragraph G of Appendix R to 10 CFR Part 50, the licensee should provide alternate snutdown capability for each of the following areas:
Cable Tray and Personnel Corridor Area Intake Structure Compressor Area Electrical Penetration Area Switchgear Area The alternate shutdown system should meet the requirements of Section III, Paragraph L of Appendix R to 10 CFR Part 50.
These items are, therefore, still open pending completien of the staff's evaluation of the alternate shutdown system proposed by 0 PPD.
c Item 3.1.16 - Fire i'ater Supoly In the Fire Protection SER the ccncern was that sand and silt from the riverbed could clog sprinkler lines or prevent the fire pumps fron operating.
By letters dated July 13, 1978 and May 20, 1930, the licensee provided a description of the current pump suction line design, the results of normal surveillance testing since modifications were completed, and the results of testing a mock-up of a sprinkler system.
The test results indicate that the quantity of sand which flowed through the piping is unlikely to impair the perfomance of fire pucps or sprinklers.
In addition the licensee indicated that the fire pump discharge strainer had a 250 micron screen and that all orifices in the sprinkler system are 1/4 inch or larger. The licensee concluded that sand-clogging of sprinkler l
system pipes or oriffCEs through which water is flowing is unlikely.
I Although we agree that upol operation of the fire pump due to the opening of a sprinkler head, sand would probably not clog the piping leading to l
that sprinkler or the sprinkler itself, sufficient sand may be introduced into the non-flowing portions of the system to build up to a point where individual sprinklers or small pipe sections would become clogged, thus not available for future operation.
l
~,.
n
L I
. To assure that sprinkler orifices and pipes will not be clogged by a buildup of sand or silt, the licensee should establish procedures to examine, test, or flush sprinkler system portions in which no flow occurred if one or more sprinklers in that system have operated. The procedures should follow the recommendations of NFpA 13A-1978, " Recommended Practice for the Care and Maintenance of Sprinkler Systems."
The staff finds this item to be acceptable provided the licensee establishes procedures to examine, test or flush the sprinkler systems as stated above.
This item, therefore, is still open pending receipt of information that such procedures have been established and are adhered to.
Item 3.1.20 - Cable Penetration Seals SER Section 3.1.20 indicates that the licensee will upgrade the electrical cable penetration seals to a design demonstrated by test to have a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire resistance rating.
By letter dated October 18, 1978, the licensee described the proposed modifi-cations to achieve the 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire resistance rating. The licensee also indicated that penetration seals being installed have passed tests conducted generally in agreement with the methods and criteria described in the NRC August 30, 1977 letter to the Omaha Public Power District, except that nc pressure differential was applied across the seals during the test.
The licensee stated that Chemtron Corporation, to whose installation procedures Fort Calhoun cable penetration seals have been installed, acknowledged that a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire test was successfully conducted with a positive pressure of 9.0 inches of water maintained on a 5,885 square inch penetration.
Because the largest penetration in the plant is 1,924 square inches, and because the maximum expected nonfire differential pressure is approximately 0.5 inches of water, we find the proposed modifications for cable penetration seals satisfactory and consider this item to be closed.
Item 3.1.21 - Alternate Shutdown Cacability SER Section 3.1.21 required the licensee to provide alternate shutdown capability to preserve safe shutdown capability in the event of a fire in the control room or cable spreading room.
By letter dated September 18, 1979, the staff provided OPPD with the NRC's Positions related to Safe Shutdown Capability.
The licensee responded to the staff positions by letters dated October 12 and November 15, 1979. The staff is presently reviewing these and other related submittals on this subject.
As noted above and in this SER, Sections 3.1.15 and 3.2.4, the Alternate Shutdown Capabilit; est be shown to meet the orovision of Appendix R to 10 CFR 50. Thn i.em is, therefore, still opea, pending completion of the staff's review of the information submitted by the licensee.
Item 3.1.25 - Cable Spreading Room SER Section 3.1.25 indicates, in part, that the licensee would use fire retardant coatings (Flamemastic) on cables in the cable spreading room in addition to the automatic Halon system.
By letter dated August 8, 1980, the licensee presented the District's belief "that the installation of Flamemastic in the cable spreading room is unnecessary in light of additional actions taken to ensure protection in that area.
Additional protection features include:
(1) installation of an automatic Halon.
suppression system, (2) increa.ed manual fire suppression capabilities consisting of a manual hose station and portable extinguisher outside each of the two entrances, (3) an upgrading of fire detection capability consisting of two additional local alarm lights and five smoke detectors that alam in the control room, and (4) a newly installed alternate shutdown c>pa:.ility to further ensure that complete destruction of the cables in the spread'ng room will not inhibit a safe plant shutdown, if required. The Flamemastic coating would also make it difficult to locate cable faults and adjacent cabling damage, thereby creating a situation where safety may be, degraded instead of improved.
Furthermore, the use of Flamemastic would make any cable rerouting extremely difficult, and rerouting may be required if the proocsed rule concerning minimum fire protection requirements for nuclear power plants is implemented in its present form."
The staff has considered the advisability of installing the Flamemastic in the cable spreading room and concurs with the licensee that its installation is not necessary since the deletion of this requirement does not significantly compromi-se the fire protectior, capability for this area.
We, therefore, consider this item to be cla?ed.
l Item 3.1.28 - Prote:ction or Stairways and Open Hatch I
In the Fire Protection SrR, the concern was that the sepration between the basement and ground 'evels of Fire Area 34 (Electrica Penetration Area) and between the Fi'a Areas 6 (Cable Tray and Personnel Corridor Area) and 20 (Personnel (.irridor Area) would not be adequate to prevent l
a fire from spreading to the adjacent areas.
By letters dated December 12, 1979 and January 18, 1980, the licensee committed to install a water curtain sprinkler system at the open stairway and open hatch which join personnel corridors in the basement level (Fire Area 6) and the ground level (Fire Area 20).
We, therefore, find the fire protection provided for Areas 6 and 20 at. eptable.
The licensee has also enclosed the stairway in the electrical penetration area with fire barriers to provide a 3-Mur rated separation between the basement and ground levels.
l Based on the above, the staff finds this item to be resolved satisfactorily l
and we consider it to be closed.
l
... Item 3.2.1 - Rupture of Fire Water Pioing SER Section 3.2.1 indicate.1 the licensee would analyze the effects of rupture of fire water piping, to be installed, on safety-related equipment.
By letter dated June 29, 1979, the licensee provided the results of the effects on safety-related systems of fire water pipe rupture and design considerations to be employed to mitigate the consequences of such ruptures.
By letter dated December 12, 1979, the licensee provided additional infoma-tion addressing the effects on safety-related equipment of rupture of fire water piping to show that safety systems will not be affected.
Based on our review, we find that rupture of fire water piping will not affect safety systems and, therefore, we find the existing fire protection water distribution system acceptable and consider this item to be closed.
Item 3.2.2 - Testina Fire Detectors SER Section 3.2.2 indicates that the licensee will provide the basis and criteria for the installation and testing of fire detectors in the plant.
By letter dated January 8,1979, the licensee submitted a Fire Detector Analysis which outlined the basis for location, spacing, and number of fire detectors in plant Fire Areas 1 through 43.
In addition, the Fire Detector Analysis provided descriptions and drawings of all safety-related plant areas.
By letter dated July 9,1979, the licensee responded to staff questions and concerns raised during a May 23, 1979 conference call.
Staff evaluation i'dicated that the licensee's Fire Detector Analysis was generally less couervative than NFPA 72E in detemining the spacing of fire detectors below non-smooth ceilings. The practical result is that detection times may be longer than that which could be achieved by compliance with NFPA 72E.
For areas in which only one division of safety-related equipment or cables is located, a small delay in fire detection, although not desirable, is tolerable.
However, it is imperative that detection in areas c.ontaining redundant divisions of safety-related equipment or cable be grompt relative to the i
rate of fire spread.
By telephone conversation on April 18, 1980 as do:uinented and supplemented by letter dated May 20, 1980, the licensee acouiesced to the staff's position and resolved our co:.cerns.
The staff, therefore, finds this itr.m to be acceptable and considers it closed.
l
- a Item 3.2.3 - Reactor Coolant Pump Oil Collection System SER Section 3.2.3 indicates that the licensee will provide one of the following:
- 2) A fire suppression system to control a lube oil fire and to protect the reactor components from that fire.
The results of a study demonstrating that safe shutdown will not be 3) impaired in the event of an unmitigated reactor coolant pump lube oil fire.
By letter dated June 6,1979, the licensee proposed to install lube oil collection systems and provided the design description and drawings for the proposed systems.
The staff has reviewed this information and find that our concern has been satisfactorily addressed. We consider this issue to be closed.
Item 3.2.4 - Cable Separation (See item 3.1.15)
Technical Specifications The revisions to the Technical Specifications issued with this License Amendment are, for the most part, additions to incorporate the various modifications which were required by the staff. A number of separate applications had been submitted to incorporate added fire detection and suppression systems, these applications were combined and the entire section of fire protection Technical Specifications was updated to the currently approved version of the Standard Technical Specifications with the agreement Since the changes to the Technical Specifications incorporate of the licensee.
t additional NRC requirements and are in accordance with these currently approved, we find the Technical Specifications to be acceptable.
Sumary The staff has completed the review of all fire protection infonnation submitted to date, except for Alternate Shutdown Capability, and, as discussed above, has reached satisfactory resolution on all items listed in Tables 3.1 and 3.2 of our August 23, 1978 SER with the exception of the j
following:
\\
g-3.1.15 - Cable Separation -- Alternate Shutdown Capabilities in accordance a
with Appendix R to 10 CFR 50, need to be verified.
3.1.16 - Fire Water Supply -- Procedures to examine, test or flush the sprinkler system need to be established.
3.1.21 - Alternate Shutdom Capability -- Completion of staff review of the submitted ir.:omation and licensee verification of compliance with provisions of Appendix R to 10 CFR 50.
3.2.4 - Cable Separation -- See item 3.1.15.
Environmental Consideration We have detemined that the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact.
Having made this detemination, we have further concluded that the amendment involves an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR 551.5(d)(4), that an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance of the amendment.
Conclusion We have concluded, based on the considerations discussed above, thoc:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Date:
November 17, 1980
. e e-w
--m
-