ML19344D213

Forwards Items 3.2.1 & 3.2.10 of Fire Protection Review, Re Fire Hazard Analysis & Fire Water Drainage,Respectively

ML19344D213
Person / Time
Site:	Calvert Cliffs
Issue date:	03/04/1980
From:	Randy Hall BROOKHAVEN NATIONAL LABORATORY
To:	Ferguson R Office of Nuclear Reactor Regulation
References
NUDOCS 8003110546
Download: ML19344D213 (4)

Text

.

h,,i

,,,,, BROOKHAVEN NATIONAL LABORATORY ASSOCIATED UNIVERSITIES, INC.

..L .

Upton. New York 11973 Depc.tment cf Nuclear Energy (516) 345- 21g

/

March 4, 1980 g 40 bb)th Mr. Robert L. Ferguson Plant Systems Branch U.S. Nuclear Regulatory Commission Washington, D.C. 20555 RE: Calvert Cliffs, Fire Protection Review, Items 3.2.1 and 3.2.10.

Dear Bob:

Attached are items 3.2.1, Fire Hazard Analysis, and 3.2.10, Fire Water Drainage for the Calvert Cliffs Nuclear Power Plant.

This concludes our current input for this plant.

Respectfully yours, WP MMr.e Robert E. Hall, Group Leader Reactor Engineering Analysis REH:EAM:sd attachments cc.: W. Kato wo/att.

T. Lee M. Levine wo/att.

E. MacDougall V. Panciera

\k 800g 10 s'yg y

l 1

CALVERT CLIFFS Fire Protection Review Item 3.2.1 - Fire Hazard Analysis SER Section 3.2.1 indicates that the licensee will provide results of an an-alysis to:

1. demonstrate the adequacy of separation between adjacent fire areas that are not separated by fire barriers (with protected openings and pene-trations) of appropriate fire resistance, *

2. identify the minimum separation between the redundant cables (in trays or in conduits)/ equipment required for safe shutdown in each fire area,

3. identify the largest fire that can be expected in each fire area based on the fixed combustibles in the area and transient combustibles which may be introduced into or moved through the area,

4. identify the worst damage that could result from such fire, and

5. demonstrate that such damage will not have an adverse effect on safe shut-down or cause excessive radioactive release to the environment.

The analysis will, as a minimum, include the following considerations:

1. The possibility that redundarit cables (in trays or in conduits)/ equipment may be involved in an exposure fire due to fixed or transient combust-ibles.

2. Effects of the fire and possible explosion, and fire fighting activities.

3. Shutdown capability without offsite power.

4. Safe shutdown consequences of possible system transients resulting from a fire induced faulting of electrical cables.

Where assumptions are made, such as operability of damaged cabling / equipment, or effectiveness of protection, etc., they will be substantiated by the re-suits of tests and/or analyses.

In those plant areas where it cannot be demonstrated that safe shutdown capability can be preserved during and following the postulated fire, appro-priate modification (s) will be provided to assure that the plant's shutdown capability will meet the following criteria as the minimum:

1. Following any fire, the plant can be brought to hot shutdown conditions using equipment and systems that are free of fire damage.

2. The plant shall be capable of maintaining hot shutdown conditions for an extended time period significantly longer than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

3. Fire damage to systems necessary to achieve and maintain cold shutdown conditions shall be limited so that repairs can be made and cold shutdown conditions achieved within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

4. Repair procedures for cold shutdown systems shall be prepared now and material needed for such repairs shall be on the site.

5. The hot shutdown condition shall be achieved with power from the offsite power system, and upon its loss, with power from the onsite power system.

A dedicated power supply may be substituted for the onsite power systems.

6. The power needed to achieve the cold shutdown condition may be obtained

, from any one of the offsite power, onsite power, and dedicated power sys- -

tems.

7. When these minimum systems are provided, their adequacy shall be verified by a thorough evaluation of:

a. Systems required for hot shutdown;

b. Systems required for cold shutdown;

c. Fire damage to power distribution systems; and

d. Interactions caused by fire damage to power and water supply systems and to supporting systems, i.e., component cooling water supply.

By letters dated December 21 and 27,1979, the licensee provided a fire hazards analysis and plant drawings, including a description of safe shutdown equipment required for hot and cold shutdown. Individual room analyses, and a compilation of proposed plant modifications. The analysis did not include the containment, which the licensee proposed to provide separately.

The staff has reviewed the criteria and assumptions which form the basis for the licensee's analysis and has concluded that they are not consistent with Appendix A to BTP 9.5-1, or with proposed Appendix R to 10 CFR part 50.

Specifically, e The licensee has assumed that an automatic fire supr,ression system will always prevent the concurrent loss of redundant divisions of cables or equipment as the result of a single fire, regardless of their arrangement, proximity and nature of the fire, or geometry of the room. In addition, the licensee has assumed that automatic fire suppression systems have 100 percent reliability.

e The licensee has proposed use of automatic sprinklers on one side of a fire barrier in lieu of doors, in many doorways. The reliability and ef-T?ctiveness of this form of protection has not been demonstrated, especial-ly where redundant cables are present on opposite sides of the doorway.

e The licensee proposes to limit automatic fire suppression systems if ade-quate physical separation exists between redundant divisions of safe shutdown cable or equipment, or where significant fire hazards do not exist. The licensee has not provided the basis for determining the adequacy of separation between redundant divisions of cables or equipment.

l

. . c, I

i In addition, several of the licensee's assumptions regarding transient com-bustibles are not acceptable. The staff does not view as realistic the as-sumption that the contents of the 55 gallon drum of liquid would spread over the entire floor area prior to ignition, regardless of the floor area. Also, the licensee's assumptions that a five gallon pail of combustible liquid would not spill is not conservative.

We are reviewing the room by room details of the licensee's response to this SER item, and will provide a complete evaluation of the licensee's response when this review is complete.

3.2.10 Fire Water Drainage SER Section 3.2.10 indicates that the licensee will perform an additional study, following the completion of hose reach tests and addition of interior hose stations and other automatic water systems, to verify that the fire water drainage in all safety-related areas is adequate and possible fire water ac-cumulation in any safety-related area will be acceptable.

By letter dated November 13, 1979, the licensee provided the results of the required study. The licensee estimated that in most areas of the auxiliary building, the flow of water from the largest sprinkler system and up to three fire hoses could result in the accumulation of up to two inches of water in t% room of sprinkler operation, and flooding of Elevation - 10' up to the top of equipment pedestals after no less than about 60 minutes of sprinkler oper-ation.

The licensee has estimated that all fires in these areas will be extinguished in 60 minutes or less, and therefore the fire water drainage is acceptable.

For a fire in one of the ECCS pump rooms, the licensee has estimated that at least 48 minutes of sprinkler operation plus two fire hoses would be required to flood one of the rooms, but the redundant rooms would be available because of water-tight entrance doors. The licensee likewise concluded that this is acceptable.

We concur and recommend that the staff accept this item.