View source for W3F1-2012-0028, Supplement 2 of License Amendment Request to Revise Technical Specification 3/4.7.4 Table 3.7-3, Ultimate Heat Sink Minimum Fan Requirements Per Train

{{Adams
| number = ML12144A135
| issue date = 05/22/2012
| title = Supplement 2 of License Amendment Request to Revise Technical Specification 3/4.7.4 Table 3.7-3, Ultimate Heat Sink Minimum Fan Requirements Per Train
| author name = Jacobs D
| author affiliation = Entergy Nuclear South, Entergy Operations, Inc
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000382
| license number = NPF-038
| contact person = 
| case reference number = TAC ME7342, W3F1-2012-0028
| document type = Letter type:W, Technical Specifications
| page count = 17
| project = TAC:ME7342
| stage = Supplement
}}

=Text=
{{#Wiki_filter:Entergy Nuclear South Entergy Operations, Inc.
17265 River Road Killona, LA 70057-3093 Tel 504 739 6660 Fax. 504 739 6678 SEntergy                                                                            Djacob2@entergy.com Donna Jacobs Vice President, Operations Waterford 3 W3F1-2012-0028 May 22, 2012 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001

==SUBJECT:==
Supplement 2 of License Amendment Request to revise Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" [TAC No. ME7342]
Waterford Steam Electric Station, Unit 3 Docket No. 50-382 License No. NPF-38

==References:==
: 1. Waterford 3 Letter W3F1-2011-0067, License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML11290A009) dated October 13, 2011.
: 2. Waterford 3 Letter W3F1-2011-0082, Supplement to License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML113290070) dated November 25, 2011.
: 3. Waterford 3 Letter W3F1 -2012-0004, Calculations Requested for License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML12023A080) dated January 18, 2012.
: 4. Waterford 3 Letter W3F1 -2012-0019, Response to Request for Additional Information, License Amendment Request to revise Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML12095A308) dated April 3, 2012

==Dear Sir or Madam:==

By letter dated October 13, 2011, as supplemented by letters dated November 25, 2011, and January 18, 2012 (References 1, 2, and 3), Entergy Operations, Inc. (Entergy) made application to amend Technical Specification (TS) 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" of the Waterford Steam Electric Station, Unit 3 (Waterford 3).
AoIM

W3F1-2012-0028 Page 2 In Reference 4, Waterford 3 committed to provide a supplement to its application to amend TS 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" to ensure a conservative revised specification is developed for NRC approval. This letter provides that supplement.
Waterford 3 TS 3/4.7.4 Table 3.7-3 specifies the minimum DCT and WCT fan requirements for given ambient temperature conditions. This request modifies the WCT fan requirements by requiring that all eight WCT fans be operable for the WCT to be considered operable, regardless of ambient temperature. This change is needed because the current WCT fan requirement limits for operation with fans out of service were based on an inappropriate analysis methodology. Waterford 3 has entered this condition into the corrective action process (Condition Report CR-WF3-2012-1395) to identify the inappropriate methodology.
The revised analysis demonstrates that the Ultimate Heat Sink (UHS) remains capable of transferring the design basis heat load while maintaining the required cooling water supply temperature.
For the current configuration with all 8 WCT fans operable, design basis calculations validated by thermal performance testing completed by System Engineering on a 5 year frequency demonstrate that the WCT is capable of performing its design basis function.
Waterford 3 has implemented administrative controls, in accordance with NRC Administrative letter 98-10 to address potential non-conservatisms in the TS limits for WCT fan requirements.
A mark-up of the tentative changes to TS Bases 3/4.7.3 is included for information.
The proposed change has been evaluated in accordance with 10 CFR 50.91(a)(1) using criteria in 10 CFR 50.92(c), and it has been determined that the change involves no significant hazards considerations.
The proposed change involves no new commitments. Please contact William Steelman, Licensing Manager, at 504-739-6685 if there are any comments regarding this response.
I declare under penalty of perjury that the foregoing is true and correct. Executed on May 22, 2012.
Sincerely, Attachments:
: 1. Analysis of Proposed Technical Specification Change
: 2. Proposed Technical Specification Changes (mark-up)
: 3. Proposed Technical Specification Changes (clean copy)
: 4. Tentative Technical Specification Bases Changes (mark-up)

W3F1 -2012-0028 Page 3 cc:    Mr. Elmo E. Collins, Jr.                     RidsRgn4MailCenter@nrc.gov Regional Administrator U. S. Nuclear Regulatory Commission Region IV 1600 E. Lamar Blvd.
Arlington, TX 76011-4125 NRC Senior Resident Inspector                Marlone.Davis@nrc.gov Waterford Steam Electric Station Unit 3      Dean.Overland@nrc.gov P.O. Box 822 Killona, LA 70057-0751 U. S. Nuclear Regulatory Commission          Kaly.Kalyanam@nrc.gov Attn: Mr. N. Kalyanam Mail Stop O-07D1 Washington, DC 20555-0001 Louisiana Department of Environmental        Ji.Wiley@LA.gov Quality Office of Environmental Compliance Emergency and Radiological Services Division P. O. Box 4312 Baton Rouge, LA 70821-4312

Attachment I to W3F1-2012-0028 Analysis of Proposed Technical Specification Change to W3F1`-2012-0028 Page 1 of 6

==1.0     DESCRIPTION==

By letter dated October 13, 2011, as supplemented by letters dated November 25, 2011, and January 18, 2012 (References 7.1, 7.2, and 7.3), Entergy Operations, Inc. (Entergy) made application to amend Technical Specification (TS) 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" of the Waterford Steam Electric Station, Unit 3 (Waterford 3).
In Reference 7.4, Waterford 3 committed to provide a supplement to its application to amend TS 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" to ensure a conservative revised specification is developed for NRC approval. This letter provides that supplement.
Waterford 3 TS 3/4.7.4 Table 3.7-3 specifies the minimum DCT and WCT fan requirements for given ambient temperature conditions. This request modifies the WCT fan requirements by requiring that all eight WCT fans be operable for the WCT to be considered operable, regardless of ambient temperature. This change is needed because the current WCT fan requirement limits were based on an inappropriate analysis methodology. Waterford 3 has entered this condition into the corrective action process (Condition Report CR-WF3-2012-1395) to identify the inappropriate methodology.
The revised analysis demonstrates that the Ultimate Heat Sink (UHS) remains capable of transferring the design basis heat load while maintaining the required cooling water supply temperature.
For the current configuration with all 8 WCT fans operable, design basis calculations, validated by thermal performance testing completed by System Engineering on a periodic basis, demonstrate that the WCT is capable of performing its design basis function.
Waterford 3 has implemented administrative controls, in accordance with NRC Administrative letter 98-10 to address potential non-conservatisms in the TS limits for WCT fan requirements.

==2.0      PROPOSED CHANGE==

The proposed modification of TS Table 3.7-3 will be to specify that all WCT fans are required to be operable for the WCT to be considered operable. The previous submittal W3F1-2011-0067 (Reference 7.1) continues to request the dry bulb temperature limits for the DCT to be reduced. These changes are intended to correct non-conservatisms in the TS relative to the WCT and account for increased heat load due to the Replacement Steam Generators. The specific TS changes are listed below.
For the DCT, lower the ambient dry bulb temperature limit for 14 fans from 98 0 F to 97 0 F.
For the WCT, require all eight fans regardless of ambient temperature.
to W3F1-2012-0028 Page 2 of 6 3.0     ..BACKGROUND The function of the Ultimate Heat Sink (UHS) is to dissipate the heat removed from the reactor and its auxiliaries during normal operation, during refueling, or after a design basis accident. The UHS consists of a DCT, a WCT, and the water stored in the WCT basins. Two 100% capacity trains employ one DCT and one WCT each.
The DCT removes heat from the Component Cooling Water (CCW) system, which is a closed cooling system that serves reactor auxiliaries. The Auxiliary Component Cooling Water (ACCW) system is a separate system that provides cooling water to the CCW heat exchanger and utilizes the WCT for heat dissipation to the atmosphere. The CCW and ACCW systems are described in the Updated Final Safety Analysis Report (UFSAR) Section 9.2.2.
Each DCT is sized to dissipate approximately 60% of heat removed by the CCW System after a Loss of Coolant Accident (LOCA). The heat removal capacity of the DCT varies significantly depending on the CCW temperature, atmospheric dry bulb temperature, and the heat removal by the ACCW system. Each DCT consists of five separate cells; each cell contains two vertical cooling coils. Cooling for each cell is provided by three fans. In Emergency operation, the DCT fans are started and shut-off automatically to maintain the CCW supply temperature at a predetermined setpoint. When the water outlet temperature of the CCW Heat Exchanger exceeds another predetermined setpoint, the associated ACCW pump automatically starts, which initiates heat removal via the WCTs.
The WCT is designed to operate whenever the heat rejection capacity of the DCT is exceeded or ambient conditions degrade the ability of the DCT to reject its heat load. The WCT ban also be used to maintain the CCW system temperature below the range, maintained by the DCT during normal operation.
Each WCT is sized to dissipate approximately 40% of the heat removed by the CCW system after a LOCA to the atmosphere. The capacity of the WCT varies significantly, depending on the CCW temperature to be maintained and the atmosphere wet bulb temperature. Each WCT consists of two cells separated by a concrete barrier, which prevents air recirculation between the fans of each cell. The WCT fans are started automatically whenever the water temperature in the WCT basin exceeds a predetermined setpoint.
The previous method for determining the WCT fan requirements for a given ambient temperature used a Cooling Tower Institute (CTI) equation that is not intended for that purpose. The equation correlates cooling tower performance to the cube root of the ratio of actual fan horsepower to design fan horsepower. A cooling tower industry expert confirmed that the equation is intended to be used for comparing design performance to test performance where small changes in fan horsepower were measured. It was not intended to predict tower performance where total fan horsepower is reduced by large amounts.
Therefore, the results of the analysis and the associated TS limits are potentially non-conservative.
In addition, after the Replacement Steam Generators are installed, the UHS will have a higher heat duty, which impacts the ambient temperature limits on TS Table 3.7-3.
to W3F1-2012-0028 Page 3 of 6

==4.0     TECHNICAL ANALYSIS==

The current TS Table 3.7-3 for WCT fan requirements for a given ambient temperature is not conservative because it is based on inappropriate analysis methodology.
TS Table 3.7-3, which specifies the number of WCT fans operable for a given wet bulb temperature, will be revised. All eight fans will be required for the WCT to be considered operable regardless of ambient temperature.
This change is necessary because the design basis analysis for determining the ambient temperature limits with WCT fans out of service used an inappropriate methodology.
In addition to the changes to address the non-conservatisms in TS Table 3.7-3, the dry bulb temperature limit for one DCT fan out-of-service will also be lowered to account for the increased heat load as a result of the Replacement Steam Generators. For the DCT, the temperature was lowered so that all 15 fans are required to be operable with a dry bulb temperature greater than or equal to 97 0 F. The ambient temperature limit for 3 DCT fans out-of-service will remain unchanged at < 91OF.
The revised temperature is based on calculations ECM95-008, ECM95-009, and ECI91-029, and additional margin. With the above changes, the UHS will continue to meet its design function to dissipate the heat removed from the reactor and its auxiliaries during normal operation, during refueling, or after a design basis accident. The TS Bases 3/4.7.4 indicates that the calculated temperature values associated with the fan requirements have been rounded in the conservative direction and lowered at least one full degree.

==5.0      REGULATORY ANALYSIS==

5.1     Applicable Regulatory Requirements/Criteria Entergy Operations, Inc. (Entergy) proposes to modify TS Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train," by specifying that all eight WCT fans are required regardless of ambient temperature and lowering the dry bulb temperature limit for one DCT fan out-of-service. This change will correct a non-conservative TS and account for increased heat load resulting from the Replacement Steam Generators.
This change to TS Table 3.7-3 does not involve any physical changes to the plant or to the CCW/ACCW system design that would affect the intent of the General Design Criteria, national standards, or engineering principles. Consistency.with the defense-in-depth philosophy is maintained in that the independence of fission product barriers has not been degraded by the TS change. Sufficient safety margins are maintained in that the proposed change is not in conflict with approved Codes and standards relevant to the CCW/ACCW system, such as GDC 2, GDC 44, ANSI N18.2-1973, ANSI N18.2a-1975, Regulatory Guide 1.27-1976, Regulatory Guide 1.29-1973, and Regulatory Guide 1.53-1973. The proposed changes will lower the ambient temperature limit for one DCT fan out-of-service in Table 3.7-
: 3. The revised temperature is based on calculations ECM95-008, ECM95-009, and ECI91-029, and additional margin. With the above changes, the UHS will continue to meet its design function to dissipate the heat removed from the reactor and its auxiliaries during normal operation, during refueling, or after a design basis accident. The revised analysis to W3F1-2012-0028 Page 4 of 6 demonstrates that the UHS remains capable of transferring the design basis heat load while maintaining the required cooling water supply temperature. The TS Bases 3/4.7.4 indicates that the calculated temperature values associated with the fan requirements have been rounded in the conservative direction and lowered at least one full degree.
In conclusion, Entergy has determined that the proposed change does not require any exception or relief from regulatory requirements and does not adversely affect systems, structures, and components described in the Waterford 3 FSAR. Based on FSAR 9.2.5, the function of the UHS is to dissipate the heat removed from the reactor and its auxiliaries during normal operation, during refueling or after a design basis accident. The proposed changes to place more restrictive ambient temperature limits for DCT fans and increase WCT fan requirements do not adversely affect the design function, method of controlling a design function, or any method of evaluation that demonstrates intended design function of the UHS as described in the FSAR.
5.2      No Significant Hazards Considerations Entergy Operations, Inc. has evaluated whether or not a significant hazards considerations is involved with the proposed amendment by focusing on the three standards set forth in 10CFR50.92, "Issuance of amendment," as discussed below:
: 1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No.
The proposed change modifies Technical Specification (TS) 3/4.7.4 Table 3.7-3 to be consistent with the revised design basis calculation for Dry Cooling Tower (DCT) fan requirements and to compensate for an inappropriate methodology in the calculation for Wet Cooling Tower (WCT) fan requirements. This change is necessary to preserve the assumptions and limits of the revised Ultimate Heat Sink (UHS) design basis calculation. The calculation determines the number of cooling tower fans required for a given ambient temperature and establishes more restrictive cooling tower fan operating requirements. The proposed change does not directly affect any material condition of the plant that could contribute to an accident or that could contribute to the consequences of an accident. The proposed change ensures that the mitigating effects of the UHS will be consistent with the design basis analysis.
Therefore, the proposed change will not involve a significant increase in the probability or consequences of any accident previously evaluated.
: 2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?
Response: No.
The proposed change modifies TS 3/4.7.4 Table 3.7-3 to be consistent with the revised design basis calculation for DCT fan requirements and to compensate for an inappropriate methodology in the calculation for WCT fan requirements. The revised TS lowers the dry bulb temperature limit for one DCT fan out-of-service to account for increased heat load due to the Replacement Steam Generators. This change also to W3F1-2012-0028 Page 5 of 6 implements more restrictive WCT minimum fan requirements. The proposed change to Table 3.7-3 does not alter the operation of the plant or the manner in which the plant is operated such that it creates credible new failure mechanisms, malfunctions, or accident initiators. Therefore, the proposed change will not create the possibility of a new or different kind of accident from any accident previously evaluated.
: 3. Does the proposed change involve a significant reduction in a margin of safety?
Response: No.
The proposed change modifies TS 3/4.7.4 Table 3.7-3 to be consistent with the revised design basis calculation for DCT fan requirements and to compensate for an inappropriate methodology in the calculation for WCT fan requirements. More restrictive cooling tower fan operability requirements result from lowering the ambient temperature limit for one DCT fan out-of-service and requiring all eight WCT fans, regardless of ambient temperature. The revised temperatures are based on calculations ECM95-008, ECM95-009, and ECI91-029, and additional margin. The TS Bases 3/4.7.4 indicates that the calculated temperature values associated with the fan requirements have been rounded in the conservative direction and lowered at least one full degree. The proposed change preserves the margin of safety by ensuring that the UHS is capable of transferring the required heat load and maintaining cooling water supply temperature within limits with the minimum number of operable fans for a given ambient temperature. The proposed change does not exceed or alter a design basis or safety limit. Therefore, the proposed change will not involve a significant reduction in a margin of safety.
Based on the above, Entergy concludes that the proposed amendment presents no significant hazards considerations under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards considerations" is justified.
5.3      Environmental Considerations The proposed amendment does not involve (i) a significant hazards considerations, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 1 OCR51.22(c)(9). Therefore, pursuant to 10CFR51.22(b),
no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.
6.0      PRECEDENCE There is no precedence identified.
to W3F1-2012-0028 Page 6 of 6

==7.0    REFERENCES==

7.1    Waterford 3 Letter W3F1 -2011-0067, License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML11290A009) dated October 13, 2011.
7.2    Waterford 3 Letter W3F1-2011-0082, Supplement to License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML113290070) dated November 25, 2011.
7.3. Waterford 3 Letter W3F1-2012-0004, Calculations Requested for License Amendment Request, Proposed Change to Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML12023A080) dated January 18, 2012.
7.4,   Waterford 3 Letter W3F1-2012-0019, Response to Request for Additional Information, License Amendment Request to revise Technical Specification 3/4.7.4 Table 3.7-3, "Ultimate Heat Sink Minimum Fan Requirements per Train" (ADAMS Accession No. ML12095A308) dated April 3, 2012 7.5    Technical Specifications (TS).
7.6    Updated Final Safety Analysis Report (UFSAR) Revision 305.

Attachment 2 to W3F1-2012-0028 Proposed Technical Specification Changes (mark-up) to W3F1-2012-0028                    [Note that the change reflected for the Dry Cooling Tower is replicated from the Page 1 of 1                       previously submitted mark-up.]
AMBIENT
         &#xfd;CONDITION                                                                                            I Fan               15                   14'                         12, Roquirmmontsl 7L ~~  ~ ~ ~    i m~'Kam~~'fLamiad1   odIE1io of-
                                                                      -w   =              ~
stall be OPEAU--  '
WATERFORD - UMT 3                     1141 114                                       UT3 WATEFOR. NO. OS-423.13 I47.14AMENDMENT

Attachment 3 to W3F1-2012-0028 Proposed Technical Specification Changes (clean copy)
Attachment contains 1 page.

TABLE 3.7-3 ULTIMATE HEAT SINK MINIMUM FAN REQUIREMENTS PER TRAIN DRY COOLING TOWER AMBIENT CONDITIOI*N                DRY BULB > 97 0 F         97 0 F > DRY BULB > 91&deg;F     DRY BULB < 91&deg;F Fan Requirements(')                      15                             14*                      12*
WET COOLING TOWER Fan Requirements   - 8 (1) With any of the above required DCT fans inoperable, comply with ACTION d.
* With a tornado watch in effect, all 9 DCT fans under the missile protected portion of the DCT shall be OPERABLE.
WATERFORD - UNIT 3                                          3/4 7-14                            AMENDMENT NO. 95,123,39

Attachment 4 to W3F1-2012-0028 Tentative TS Bases Changes (Mark-up) to W3F1-2012-0028 Page 1 of 2 PLANT SYSTEMS BASES 314.7.4 ULTIMATE HEAT SINK The limitations on the ultimate heat sink level, temperature, and number of fans ensure that sufficient cooling capacity is available to either (1) provide normal cooldown of the facility, or (2) to mitigate the effects of accident conditions within acceptable limits.
The UHS consists of two dry cooling towers (DCTs), two wet cooling towers (WCTs), and water stored in WCT basins. Each of two 100 percent capacity loops employs a dry and wet cooling tower-Each DCT consists of five separate cells. Cooling air for each cell is provided by 3 fans, for a total of 15 per DCT. The cooling coils on three cels of each DCT (i.e. 60%) are protected from tornado missiles by grating located above the cola and capable of withstanding tornado missile impact. With a Tornado Watch in effect and the number of fans OPERABLE within the missile protected area of a OCT less than that required by Table 3.7-3, ACTION c requires the restoration of inoperable fans within 1 hour or plant shutdown as specified. This ACTION is based on FSAR analysis (subsection 9.2.5.3.3) that assumes the worst case single failure as, 1 emergency diesel generator coincident with a loss of offtite power. This failure occurs subsequent to a tornado strike and 60% cooling capacity of a DCT is assumed available.
  -"A*=N 26-12,6*3, elk Wl&
Each WCT has a basin which is capable of storing sufficient water to bring the plant to safe shutdown under all design basis accident conditions. Item a of LCO 3/4.7.4 requires a minimum water level in each WCT basin of 97% (-9.86 ft MSL). When the WCT basin water level is maintained at -9.86 ft MSL, each basin has a minimum capacity of 174,000 gallons. This minimum WCT basin capacity contains enough volume to account for water evaporation and drift losses expected during a LOCA. Additional volume is needed from the second WCT basin to handle the non-essential load of fuel pool cooling during the LOCA. (The WCTs can be manually interconnected through a Seismic Category I line.) The WCT basin is also credited as a source of Emergency Feedwater (EFW). The WCT minimum capacity bounds the amount of EFW required from the WCT basin for all design basis accidents. Each WCT consists of two cells, each cell is serviced by 4 induced draft fans, for a total of 8 per WCT. There is a concrete partitionbetwaen th~at prevents air recirculation b~etween thfans of each cell *;
Table 3.7-3 spec'jJa~51               or decreased fan OPERABILITY requirements based on outside air temperatur<'&             V   WJ The table provides the cooling tower fan OPERABILITY requirements that may vary wit outside ambient conditions. Fan OPERABILITY                            are sacified for eas          controlling parameter (i.e., dry bulb temperatures for DCT fan.10-&#xfd;=l The calculated temperature values (EC-M95-O09) associated AMENDMENT NO. 95, "4,2, ,-39 WATERFORD - UNIT 3                                    B 3/4 7-4                      CHANGE NO. 4-, 38

Attachment 4 to W3F1-2012-0028 Page 2 of 2 PLANT SYSTEMS BASES (Continued) 3/4.7.4    ULTIMATE HEAT SINK (Continued)                                      met wkan                     requirements have been rounded in the conseWdtve direction and lowered at l        -n-efiIdegre           .                            alure to-.e.4the OPERABILITY ghLients of Table 3.T-uquf             u-y-1    ,,3 applicable action. Because temper    atfui 47&#xfd;ubject                 to change during the day, ACTION d requires periodic temperature readinig to verify compliance with Table 3.7-3 when any cooling tower fan is inoperable.
The limitations on minimum water level and maximum temperature are based on providing a 30-day cooling water supply to essential equipment without exceeding their design basis temperature and is consistent with the recommendations of Regulatory Guide 1.27, "Ultimate Heat Sink for Nuclear Plants,* March 1974.
    -DRN 06-124A, Ch. 36 AMENDMENT NO. 449, WATERFORD - UNIT 3                             B 3/4 7-4 (1)                    CHANGE NO. 1&,38}}