ML18037A351

Modifies SPDES Permit NY-000 1075 to Enable Unit to Operate Under Full Load Conditions.Discharge Temp Difference Limitations Raised to 115 F

ML18037A351
Person / Time
Site:	Nine Mile Point
Issue date:	07/09/1981
From:	Loveridge W NEW YORK, STATE OF
To:	Polk P NRC
References
NUDOCS 8107150022
Download: ML18037A351 (10)

Text

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New York State Department of Environmental Conservation 50 Wolf Road,,Albany, New York 12233 Division of Mater Robert F. Flacke Commissioner July 9, 1981 Mr. Philip Polk U.S. Nuclear Regulatory Commission Washington D.C. 20555 Re: Niagara Mohawk JUL Vsm ~ g:) jag~~

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>It Nine Mile Point Unit 81 8NY-000 1075 I

Dear Mr. Polk:

We have modified the SPDES permit for the referenced facility to enable Niagara Mohawk to operate under full load conditions. Niagara Mohawk had miscalculated the operating characteristics of their facility. Therefore, we agreed to raise the discharge temperature and discharge temperature difference, limitations by 3 Degrees Farenheit to 115 Degrees Farenheit and 35 Degrees Farenheit. Department biologists have reviewed and approved these limitations.

These limitations will be incorporated in the long term 5-year permit to be written for this facility in the near future.

If you have any further questions on this matter, please contact Allan Geisendorfer at (518) 457-6717.

Very truly yours, Walter E. Loveridge, P.E.'hief Physical Systems Section Bureau of Industrial Programs MEL/ANG/fd cc: G. Metti, Niagara Mohawk EWg - Region 87 8107150022 810709 POR *DOCK 05000220 p PDR

ATTACHMENT TO LICENSE AMENDMENT NO. 46 FACILITY OPERATING LICENSE NO. DPR-63 DOCKET NO. 50-220 Replace the following pages of the Appendix "8" Technical Specifications with the enclosed pages as indicated. The revised pages are identified by Amendment number and contain vertical lines indicating the area of change.

Pacaes

LINITING CONOITIONS FOR OPERATION Thermal Haximum b,T OBJECTIVE The purpose of this Specification is to limit the thermal stress to the aquatic ecosystem by limiting the maximum LT across the main condenser inlet and the screenwell discharge bay.

SPECIFICATION Maximum hT across the main condenser inlet and the screenwell discharge bay during normal Station operation shall be limited to 35oF. If during normal Station operation the aT exceeds 35oF for eight consecutive hours, the cause of this deviation shall be investiga:ed and positive action shall be taken to prevent any such deviation in the future. In addition, a report shall be submitted in accordance w'.th Section 5.5.2.

MONITOR ING REg~J IREi4lENT The bT across the main condenser inlet and the screenwell discharge bay shall be monitored and recorded once per hour. Two resistance temperature detectors (RTD) shall measure the temperature in each location. The RTO's shall be. accurate to +1.0oF.

BASiS Lake studies and operating experience indicate that mortality o, plankton, eggs, and larvae entrained in the condenser will not have a significant effect on the. lake population of the species involved.2~3 Mith the main condenser operating at design heat load and circulating water at 95% design flow, the condenser temperature rise should not exceed 36oF. Since the service water discharges downstream of the condenser outlet, the corresponding station cooling water temperature rise across the plant should not exceed 35oF.

1.2 Maximum Discharge Temperature 115F 1.3 Maximum BTU Per Hour NOT APPLICABLE

2.1.5 Heat Treatment of Circulating Mater System 08 JECTI VE To limit the thermal stress to the aquatic ecosystem by limiting the circulating water temperature increase over lake ambient temperature resulting from tempering and reverse flow procedures.

SPEC IF I CATION When the lake inlet temperature is between 32oF and 50oF, the discharge temperature shall not exceed the lake inlet temperature by more than 50oF, except during reverse flow operations. At no time during tempering, except during reverse flow operations, shall the discharge temperature exceed 85oF.

Following a flow reversal, the discharge temperature shall not exceed the lake inlet temperature by more than the following values:

70 F for the first hour following flow reversal 60oF for the second hodr following flow reversal 50oF two hours following flow reversal and thereafter MONITORING REQUIREMENT The discharge temperature shall be monitored and recorded hourly as provided in the Monitoring Requirement of Section 2. l. l.

BASES When lake temperature is less than 50oF, part of the discharge flow in the screenwell may be recirculated to the intake to maintain condenser inlet temperature between 40oF and 50oF. This procedure is known as "tempering". The maximum circulating water temperature rise due to tempering is 18oF and occurs when the lake temperature is 32oF.

When this is added to the 35oF hT, the maximum rise is 53oF over lake inlet temperature. Maintaining the condenser inlet temper ature at no more than 50oF during tempering ensures that the discharge temperature will not exceed 85oF during tempering.

The'mount of tempering is controlled by moving a gate in the screenwell, and is normally adjusted to maintain the optimal condenser inlet temperature of approximately 45oF. The gate can be adjusted :o achieve this temperature within an error of approximately 5oF. This error includes minor tempering gate leakages wnich may be present at any time including when lake temperature is in excess of 50oF. This leakage is not considered tempering for the purpose of this specification.