ML20199F441
| ML20199F441 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 01/12/1999 |
| From: | Warren C WOLF CREEK NUCLEAR OPERATING CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20199F448 | List: |
| References | |
| WO-99-0001, WO-99-1, NUDOCS 9901210317 | |
| Download: ML20199F441 (16) | |
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W6#LF CREEK NUCLEAR OPERATING CORPORATION Cisy C. Warren Vice President & Chief Operating Omcer ,
JAN 121999 WO 99-0001 U. S. Nuclear Pegulatory Commission ATTN: Document Control Desk Mail Station: Pl-137 Washington, D. C. '20555
Reference:
Subject:
Docket No. 50-482: Application For Amendment To Technical Specification Section 3/4.7.5, Ultimate Heat Sink Gentlemen:
This letter transmits an application for amendment to Facility Operating
' License No. NPF for Wolf Creek Generating Station (WCGS). This request proposes to revise Technical Specification 3/4.7.5, Ultimate Heat Sink, by adding a new action statement. The new action statement will require verification of operability of two RHR trains, or initiation of power reducticn with only . one RHR ' train operable, when the plant inlet water
, temperature is greater than 90 degrees Fahrenheit.
The proposed new action will replace the temporary action statement requested in Reference 1 and subsequently approved by the NRC in Reference 2. This requested amendment provides the long-term resolution of the Ultimate Heat Sink temperature issue discussed in Reference 1. Wolf Creek Nucloar Operating Corporation (WCNOC) requests approval of this application no liier than June 15, 1999, to allow implementation of the proposed change prior to the. summer kl peak loading season. The amendment will be implemented within 30 days of NRC fj approval. I A Safety Evaluation for the proposed license amendment request is provided in Attachment I; a No Significant Hazards Consideration Determination, in Attachment II. Attachment III is the related Environmental Impact Determination. Marked up pages are provided in Attachment IV for the current g Technical Specifications and in Attachment V for the Improved Technical g C1
' Specifications. . Attachment VI provides a summary of the licensing commitments made in this subnittal.
1 L 9901210317 990112 PDR ADOCK 05000482 P PDR RO. Box 411/ Burkngton, KS 66839 / Phone: (316) 364 8831 An Equal Opportundy Employer M OHCVET
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, In accordance with 10 CFR 50.91, a copy of this application, with attachments, is being provided to the designated Kansas State Official. If you should have any questions regarding this submittal, please contact me at (316) 364-4048, or Mr. Michael J. Angus at (316) 364-4077.
Very truly yours, ay C. Warren CCW/dle Attachments 1
cc: V. L. Cooper (KDHE), w/a W. D. Johnson (NRC), w/a l E. W. Merschoff (NRC), w/a i K. M. Thomas (NRC), w/a l Senior Resident Inspector (NRC), w/a i i
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STATE OF KANSAS )
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Clay C. Warren, of lawful' age, being first duly sworn upon oath says that he is Chief' operating Officer of Wolf Creek Nuclear Operating Corporation; that i he has read the foregoing document and knows the content thereof; that he has !
executed that same for and on behalf of said Corporation with full power and i authority to do so; and that the facts therein stated are true and correct to the best of his knowledge, information and belief.
A ; MARY E. GIFFORD .,
6 Notary Mpc. (tde gf Kansas By h My Appt. Expires I Rf D 9lI'8'l Clay Warren Chi erating Officer SUBSCRIBED and sworn to before me this l6 day of [ M , 1999. j l
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vic Notary Public Expiration Date Id D9 I993 l r
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Attachment I to WO 99-0001
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ATTACHMENT I SAFETY EVALUATION l
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Attachment I to WO 99-0001
. Page 2 of 7 Safety Evaluation Description of the Proposed Change This request for a license amendment proposes to revise Wolf Creek Generating Station (WCGS) Technical Specification 3/4.7.5, Ultimate Heat Sink, to add a new action statement. The new action statement will replace the temporary action statement approved by the NRC in Amendment 118 which would have allowed continued operation of the plant with plant inlet water temperature greater than 90 but less than 95 degrees Fahrenheit for up to twelve (12) hours, i provided two trains of RHR were verified to be operable, before requiring I shutdown of the plant. The new action statement will require verification of operability of two RHR trains, or initiation of power reduction with only one i RHR train operable, when the plant inlet water temperature is greater than 90 degrees Fahrenheit but less than 94 degrees Fahrenheit. !
Background
The ultimate heat sink (UHS) is the normally submerged Seismic Category I cooling pond. Ine UHS is formed by providing a volume of cooling water behind a Seismic Category I dam built in one finger of the WCGS cooling lake. The two principal functions of the UHS are the dissipation of residual heat after i reactor shutdown, and dissipation of residual heat after an accident. I The UHS is the sink for heat removed from the reactor core following all i accidents and anticipated operational occurrences in which the unit is cooled I down and placed on residual heat removal (RHR) operation. Its maximum post accident heat load occurs after a design basis loss of coolant accident (LOCA) when the emergency core cooling system (ECCS) switches from injection to recirculation and the RHR system is required to remove the core decay heat.
The basic performance requirements for the UHS are that a 30 day supply of water be available, and that the design basis temperatures of safety related equipment not be exceocs The capacity of the UHS is sufficient to provide cooling for the requare wriod of 30 days with no makeup water under both normal and accident conc:.t s s. The UHS is assumed to supply cooling water to the essential service watt system (ESWS) at a rate of 30,000 gpm for the entire 30-day period for t.'.+. onalysis. The UHS has sufficient capacity to supply emergency n. ip watw to the spent fuel pool and component cooling water systems and t serve as the backup water supply for the auxiliary feedwater system Tri UHS also has sufficient capacity to allow up to 140 gpm of continuous lc es thrcughout the 30 day period due to leakage from the ESWS. The anal assumes the URS has lost a volume of 155 acre-feet due to sediment.
The UHS is designed in accordance with Regulatory Guide 1.27, which requires a 30 day supply of cooling wacer in the UHS. The UHS satisfies Criterion 3 of 10 CFR 50.36 (c) (2) (ii) . The UHS design ensures that the design temperatures of safety-related equipmint are not exceeded. The design temperature of water supplied to the plant is 35 degrees Fahrenheit.
The operating limits are based on conservative heat transfer analyses for the worst case LOCA. Section 9.2.5 of the Updated Safety Analysis Report (USAR) provides the details of the assumptions used in the analysis, which include worst expected meteorological conditions, conservative uncertainties when calculating decay heat, and postulated failure of the main cooling lake dam and baffle dike 'A'.
Tbc UHS is required to be OPERABLE and is considered OPERABLE if it contains a sufficient volume of water at or below the maximum temperature that would allow the ESWS to operate for at least 30 days following the design basis LOCA without exceeding the maximum design temperature of the equipment served by
' Attachment I to WO 99-0001 i
. -Page 3 of 7 the ESWS. To meet this condition, the initial plant inlet water temperature should not exceed 90 degrees Fahrenheit and the minimum water level should not fall below 1070 ft mean sea level during normal unit operation. l The UHS design was based upon adverse hydrological and meteorological conditions. The maximum temperature and maximum evaporation periods for ;
recorded weather conditions were considered in sizing of the UHS. Selection :
of the critical weather periods was based upon a computer analysis (UHSAVG) of '
meteorological data for a 16-year period which included a severe drought, !
estimated to have a recurrence interval of 50 years. A weather tape scan of surface weather data for Chanute, Kansas, and of precipitation data for Iola, l Kansas, for the period of 1949-1964 was performed. These data included the historic drought years of 1952-1957.
1 The 16-year weather data were used to evaluate water surface temperatures and "
evaporation rates for a prescribed rate of heat rejection from the surface of !
the UHS. The worst evaporation period was obtained by selecting the weather conditions corresponding to the 30 consecutive days for which evaporation loss i was maximum. The worst temperature period was obtained by saving the ,
conditions for the 5 consecutive days, 1 day, and 30 consecutive days i resulting in highest average water temperature after which these three periods were combined in the indicated order to produce a synthetic 36-day worst-weather period, j The maximum evaporative and temperature periods were determined to have the !
following dates: l Maximum Evaporation Period Worst 30 days: June 24, 1954 to July 23, 1954 Maximum Temperature Period Worst 5 days: June 30, 1949 to July 5, 1949 Worst I day: July 2, 1949 (Noon) to July 3, 1949 (Noon)
Worst 30 days: July 16, 1951 to August 15, 1951
, For the above listed weather periods, ultimate heat sink draw-down and plant L inlet temperatures were evaluated as a function of time using a computer model (LAKET-5) which predicts the transient response of the heat sink to external conditions.
Heat rejection rates were taken as those corresponding to a LOCA or Normal shutdown with an assumed total flow of 30,000 gpm. In addition, it was assumed that all of the water in the UHS was at 90 degrees Fahrenheit at the start of this analysis.
-Following the loss of the main dam, the highest plant inlet water temperature during the maximum temperature period is predicted to be 95 degrees Fahrenheit. The predicted plant inlet temperature was usually well below 95 j degrees Fahrenheit. The predicted plant inlet average temperature over the j entire period was slightly below 90 degrees Fahrenheit and, 95% of the time, below 94 degrees Fahrenheit.
The maximum drawdown under worst evaporative conditions, including water loss y due to lake seepage, was found to.be approximately 1.65 feet from the initial
. elevation of 1070 feet. This corresponds to a decrease in UHS volume of about 39% of the volume existing at the start of the accident. At this point the UHS water level is at 1068.35 feet, and the UHS has already provided the required 330,000 gallons of emergency makeup water and 140 gpm of ESWS losses throughout the 30 days. The plant can achieve safe shutdown in the event of postulated LOCA using only the UHS.
l Attachment I to WO 99-0001
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Evaluation l
1 The WCGS Technical Specification 3/4.7.5 action statement change requested by l WCNOC in July of 1998 and subsequently approved by the NRC in Amendment 118 of the WCGS Technical Specifications was prompted when, on July 14, 1998, the WCGS cooling lake slightly exceeded 89 degrees Fahrenheit. This temperature was higher than previously expected. An evaluation conducted by an outside contractor concluded that the combination of moderately high dry bulb temperatures, high humidity (dew point temperatures), unusually persistent and strong solar radiation due to only occasional cloud cover, and unusually low wind speed over the several days leading up to July 14, 1998, was determined to be the cause of the elevated lake temperature. The combined effect of these factors was to severely limit the lake's cooling capacity, primarily through unusually high heat input to the lake from solar radiation and suppression of normal evaporative cooling. The outside contractor also concluded that these weather conditions were slightly more effective at suppressing normal heat dissipation by the lake than the design basis weather ,
period (July-August 1951) discussed in the USAR as the basis for predicting l 87.7 degrees Fahrenheit as the peak lake temperature.
l This was an unprecedented condition that was not predictable, as the conditions being experienced were more severe than previously experienced and analyzed. The prediction at the time for continuing harsh meteorological conditions raised the concern that the plant inlet water temperature may exceed 90 degrees Fahrenheit, forcing a unit shutdown under the current WCGS Technical Specification 3/4.7.5 action statement, during a period of peak electrical demand. The action statement approved in Amendment 118 of the WCGS Technical Specifications was a temporary measure granted by the NRC with the provision that a permanent solution to this issue be provided at a later date.
This proposed license amendment is the permanent solution WCNOC is proposing to replace the temporary measure described above. The proposed change is similar to that approved in Amendment 118, in that the action statement requires verification that two trains of RHR are operable. The proposed change differs from Amendment 118 in that it will allow continued operation with plant inlet water temperature up to 94 degrees Fahrenheit for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (as opposed to 95 degrees Fahrenheit in Amendment 118) and will also j allow continued operation for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> with only one RHR train operable '
with plant inlet water temperature up to 94 degrees Fahrenheit, provided power reductions are made when plant inlet water temperature exceeds 90 degrees Fahrenheit.
The proposed change will allow for continued plant operation for extreme meteorological conditions, as noted above; however, entry into the proposed action statement for the LCO condition of plant water inlet temperature exceeding 90 degrees Fahrenheit is considered unlikely since the probability of the occurrence of environmental conditions causing the plant inlet water temperature to exceed 90 degrees Fahrenheit is low. This is demonstrated by the fact that the lake temperature recorded over the past 15 years has never exceeded 90 degrees Fahrenheit, including the 1998 conditions. and the fact that the combination of environmental conditions resulting 2n the July 1998 peak temperatures, similar to those seen in 1951, would indicate an event occurrence on the order of once in 47 years. (The lake temperature analysis assuming 1951 environmental conditions predicted a maximum temperature less than 90 degrees Fahrenheit, as well. ) Should the action statement for this LCO be entered, up to a 4 degrees Fahrenheit increase in plant inlet water temperature would be expected to have an insignificant impact on the capability to meet the performance requirement that a 30 day supply of water be available. However, the design basis temperature of 95 degrees Fahrenheit
[ for safety related equipment may be exceeded should the lake water temperature
! (plant inlet water temperature) exceed 90 degrees Fahrenheit at the initiation of an accident. As noted above, should the main dam f ail in conjunctic,n with
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Attachment I to WO 99-0001
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'he heat rejection during a LOCA or plant shutdown, the plant inlet water t
temperature may exceed 95 degrees Fahrenheit if the accident initiation is postulated to occur when the lake water temperature is in excess of 90 degrees ,
Fahrenheit. For this reason, the time that the plant will be permitted to continue operating when the plant inlet water temperature exceeds 90 degrees Fahrenheit is limited to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The possibility that the plant inlet water temperature would exceed 95 degrees Fahrenheit during this 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> period is low, and is discussed further in subsequent evaluations for safe shutdown and post-accident operation without the main dam. Other aspects evaluated below include normal plant operation, normal plant shutdown with the main dam intact, and LOCA with the main dam.
Normal plant operation Short term operation with an inlet water temperature of up to 94 degrees Fahrenheit is not expected to negatively affect plant operation, with the possible exception of turbine back pressure. A slight load reduction may be necessary to maintain acceptable turbine back pressure. Existing plant guidance will be employed if turbine back pressure becomes too high.
Continued plant operation . during long term weather conditions causing the plant inlet water temperature to exceed 90 degrees Fahrenheit is not expected to require daily entry and exit out of the proposed action statement (12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> time limit). As noted above, the probability of environmental conditions significantly worse than those' experience this summer (1988) is-low. Further, a review of data from the extreme meteorological conditions experienced this summer shows that a maximum lake water temperature is experienced only for a short duration. Dailypeaklaketemperaturesduringthistimeperiodwereonf_., '
the order of 2-3 degrees Fahrenheit lower than the overall peak lak'e waterj temperature.
Shut down with the main dam intact During normal or emergency plant cooldown operation, the cooling lake serves as a reservoir to supply water to the ESWS system. The ESWS, in conjunction with the Component Cooling Water (CCW) system and the RHR system, removes decay heat and sensible heat from the core and cools the plant from RHR entry conditions to cold shutdown during plant cooldown. The time required for this evolution is a function of the number of pumps, CCW heat exchangers, and RHR system trains that are operating. The RHR system may be placed in operation approximately four hours after reactor shutdown is initiated, when the RCS temperature is approximately 350 degrees Fahrenheit and pressure is below 360 psig.
Plant cooldown using the RHR system is calculated using a computer code. The computer code limits the cooldown rate to a maximum of 50 degrees Fahrenheit per hour, and to a rate which limits the CCW outlet temperature from the CCW heat exchanger to a maximum of 120 degrees Fahrenheit. The reactor coolant flow through the residual heat exchangers'is throttled during the early stages of cooldown to maintain a 120 degrees Fahrenheit limit. The 120 degrees Fahrenheit CCW temperature limit is dictated by cooling water temperature requirements of the reactor coolant pump, which continues to run during the early part of the cooldown.
For a normal plant design cooldown, assuming both RHR trains are in service and a 90 degrees Fahrenheit ESW temperature, the plant can be cooled down to cold shutdown conditions (200 degrees Fahrenheit) within approximately 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after reactor shutdown. However, for the single RHR train operation, the '
calculated cooldown time increases to about 32 hours3.703704e-4 days <br />0.00889 hours <br />5.291005e-5 weeks <br />1.2176e-5 months <br />.
The effect of increasing the plant inlet water temperature from 90 degrees Fahrenheit to 94 degrees Fahrenheit causes the calculated RHR cooldown time to
Attachment I to WO 99-0001
. Page 6 of 7 l 'ncrease.
i For cooldown operation using two RHR trains, the increase in l ,
cooldown time is insignificant. However, the calculated cooldown time for a single train operation with an elevated plant inlet water temperature may exceed cooldown time needed to comply with some Technical Specifications. To compensate for this concern the proposed action statement will require verification of operability of two RHR trains, or, with only one RHR train operable, initiation of power reduction when the plant inlet water temperature is greater than 90 degrees Fahrenheit. The extent of power reduction is l determined based on a sensitivity study which considers a reduced power level ;
prior to reactor trip in conjunction with an elevated plant inlet water temperature ranging from 91 degrees Fahrenheit to 94 degrees Fahrenheit. The results of the sensitivity study are summarized in the table below. As can be seen from this table, the proposed power reduction of 5% for each degree ESW temperature exceeds 90 degrees Fahrenheit (maximum reduction #of 80%)
the single RHR train cooling capacity would be adequate to meet technical ensures /
specification shutdown time requirements with ESW temperature between 91 degrees Fahrenheit and 94 degrees Fahrenheit.
The calculated cooldown times (hours after reactor shutdown) assuming one RHR train is operable, are:
ESW Power Level % (MW)t Temperature 954 (3386.8) 90% (3209) 85% (3030) 80s (2852) 91 30.0 26.8 23.8 21.2 92 32.9 29.3 26.2 23.2 93 36.5 32.5 28.9 25.7 94 41.1 36.7 32.5 28.8 Safe shut down or post-accident operation without the main dam The TS limit of 90 degrees Fahrenheit is not being changed; however, the proposed license amendment provides an allowance for operation above that limit, up to 94 degrees Fahrenheit, for up to a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> period. The WCGS accident analyses assume a plant inlet water temperature of 95 degrees Fahrenheit. Based on a review of WCGS cooling lake data, 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> may be necessary to restore the lake below 90 degrees Fahrenheit through diurnal effects.
Safe shut down capability and post-accident operation without the main dam is i ensured when the plant is operated within TS limits. The probability of main dam failure is low compared to the frequency of a large break LOCA initiating event. The probability of main dam failure during the 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when the inlet water temperature is above 90 degrees Fahrenheit in conjunction with an accident is even lower. A seismic event is a possible initiating event for causing failure of the main dam. The main dam is designed such that its slopes are stable under all reservoir operation conditions including an earthquake force equivalent to the site Operational Bases Earthquake. The frequency of the seismic initiator on an annual basis is nearly equal to a large break LOCA. The main dam and saddle dams are under the jurisdiction of the state of Kansas, Department of Agriculture, Division of Water Resources, and complies with the provisions of the state of Kansas statutes KSA 82a-301 through 305. WCGo has a surveillance program in place to monitor and observe the behavior of the main dam and associated water control structures. The program is in general compliance with the recommendations of RG 1.127, Rev. 1.
- It includes quarterly visual inspections for seepage and annual visual
! inspections of the embankments for undue vertical or horizontal settlement, slope stability, slope protection, condition of the service spillway, change l in seepage conditions and measurement / evaluation of piezometric water levels
! and inclinometer readings. Annual surveys of the settlement and slope l
monitors were periormed and an engineering report was prepared from startup through 1994. After this date, the monument surveys and engineering report frequency was increased to every 5 years. These reductions in frequency are
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. J Attachment I to WO 99-0001 l . Page 7 of 7 I
' c:onsistent with RG L.127, Position 4b, which allows extended inspections if '
, the results of previous inspections warrant this extension. Any change in the I dams' structural, hydraulic and foundation conditions can be detected promptly j l and corrected. The dam monitoring program ensures that a sudden catastrophic '
l failure of the Wolf Creek main lake dam is highly unlikely, and therefore I would be available following a LOCA. With the main dam intact, and the lake
} temperature at 94 degrees Fahrenheit or less, the LOCA analyses are preserved.
l That is because the LOCA analyses are based on 95 degrees Fahrenheit lake i temperature, and heatup to the lake following a LOCA is minimal. Therefore, '
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it is concluded that this proposed change is of low risk significance.
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j LOCA with the main dam The effect of full power plant. operation on plant inlet water temperature during worst case predicted summer environmental conditions is approximately
! 0.5 degrees Fahrenheit. The peak heat rejection rate by the plant post-LOCA l would be approximately 5% of the continuous heat rejection rate of the plant .
during normal operation. Therefore, the effect of post-LOCA heat loads on . !
plant inlet water temperature would be less than 0.1 degrees Fahrenheit. l The current UHS analysis assumes that there has been a main dam failure and
! uses assumed worst case environmental conditions. The results indicate that l with an initial UHS temperature of 90 degrees Fahrenheit, peak plant intake water temperature is expected to be 95 degrees Fahrenheit or less. Current I plant Design Basis Accident analyses were performed assuming a continuous l' plant intake water temperature of 95 degrees Fahrenheit. The UHS analysis results also indicate that the environmental conditions have a much greater effect on peak plant intake water temperature than the heat rejected from the ,
plant. The current UHS analysis is recognized as bounding the LOCA condition '
with the main dam intact cecause the volume of the UHS is significantly smaller than the volume of the WCGS cooling lake, approximately 1%.
f i The probability that environmental conditions significantly worse than those i causing entry into the LCO is low. The probability of these conditions I occurring simultaneously with a LOCA is even lower.
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Attachment II to WO 99-0001
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l ATTACHMENT II NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION l
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. 1 Attachment II to WO 99-0001
. Page 2 of 3 No Significant Hazards Consideration Determination Proposed Change This license amendment request.' proposes to revise Wolf Creek Generating Station (WCGS) Technical Specification 3/4.7.5, Ultimate Heat Sink, to add a new action statement. Specifically, the new , action statement will allow continued operation of the plant at full power or reduced power, as necessary, with plant inlet water temperature up to 94 degrees Fahrenheit for up to twelve _ (12) hours before requiring shutdown of the plant. This new action statement replaces the temporary action statement granted by the NRC in Amendment 118 of the WCGS Technical Specifications.
The following sections discuss the proposed change under the three standards of 10 CFR 50.92.
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Involves a Significant Increase in the Probability or ;
Consequences of an Accident Previously Evaluated The proposed change does not involve any physical alteration of plant systems, structures er components. The proposed change provides an allowed-time for the plant to continue operation with plant inlet water temperature in excess of the current technical specification limit of 90 degrees Fahrenheit, up to 94 degrees Fahrenheit, which is less than the design limit of 95 degrees Fahrenheit for plant components. The plant inlet water temperature is not assumed to be an initiating condition of any accident analysis evaluated in the updated safety analysis report (USAR). Therefore, the allowance of a limited time for the water temperature to be in excess of the current limit does not involve an increase in the probability of an accident previously evaluated in the USAR. The UHS supports operability of safety related systems used to mitigate the consequences of an accident. Plant operation for brief periods with plant inlet water temperature greater than 90 degrees Fahrenheit up to 94 degrees Fahrenheit will not adversely affect the operability of these safety-related systems and will not adversely impact the ability of these systems to perform their safety-related functions. Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated in the USAR.
Standard II - Create the Possibility of a New or Different Kind of Accident from any Previously Evaluated The proposed change does not involve any physical alteration of plant systems, structures or components. The temperature of the plant inlet water being greater than 90 degrees Fahrenheit but less .than or equal to 94 degrees Fahrenheit for a short period does-not introduce new failure mechanisms for systems, structures or components not already considered in the USAR.
Therefore, the possibility of a new or dif ferent kind of accident from any accident previously evaluated is not created.
Standard III - Involve a Significant Reduction in the Margin of Safety The proposed change will allow an increase in plant inlet water temperature above the current technical specification limit of 90 degrees Fahrenheit for the Ultimate Heat Sink, and delay the requirement.to shutdown the plant when the plant inlet water system temperature limit is exceeded for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The proposed change does not. alter any safety limits, limiting safety system settings, or limiting conditions for operation, and the proposed temperature ,
increase will remain ' below the design limit cooling water input value for 1 safety-related equipment, except for the unlikely event of a combination of a worst dam failure occurring with a loss of coolant accident during a period of severe meteorological conditions. Thus, the proposed change does not involve a'significant reduction in any margin of safety.
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' Attachment.II to WO 99-0001
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based on the' above discussions, . it has been determined that the requested 'f
.* technical specification revision does not involve a significant increase in '
the probability . of consequences of an accident or other adverse conditions over. previous evaluations; or create the possibility ' of a new or different kind of accident or condition over previous evaluations; or involve a t significant. reduction in a. margin of sefety. Therefore, the requested lice'se n f amendment does not: involve a significant hazards consideration. l i
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Attachment III to WO 99-0001 Page 1 of 2 4
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ATTACHMENT III ENVIRONMENTAL IMPACT DETERMINATION i
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Attachment III to WO 99-0001
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- l. Environmental Impact Determination ,
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t 10 CFR 51.22(b) specifies the criteria for categorical exclusions from the I
I requirement for a specific environmental assessment per 10 CFR 51.21. This amendment request meets the criteria specified in 10 CFR 51. 22 (c) ( 9) as specified below:
(i) the amendment involves no significant hazards consideration As demonstrated in Attachment II, the proposed changes do not involve any ;
significant hazards considerations.
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(ii) there is no significant change in the types or significant increase in j the amounts of any effluents that may be released offsite ]
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The proposed change does not involve a change to the . facility or operating j procedures that would cause an increase in the amounts of effluents or create- i new types of effluents. While the predicted increase in cooling lake i temperature is higher than previously experienced, this increase is due to ]
environmental effects of nature, not from plant operation. Plant operation i with plant inlet water temperature. greater than 90 degrees Fahrenheit but less !
than or equal to 94 degrees Fahrenheit for short periods will not cause a l l significant change in the types of or a significant increase in the amounts of l l
any effluents that may be released offsite. 'In addition, WCNOC review of 1 potential environmental impacts concluded that the higher lake temperatures I will not significantly increase thermal impacts to the lake's biota (i.e., l benthic organisms, phytoplankton, zooplankton, and fish) greater than i previously evaluated by the NRC in the Final Environmental Statement i (NUREG-0878).
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(iii) there is no significant increase in individual or cumulative l occupational radiation exposure This change has no relation to occupational radiation exposure, either individual or cumulative.
l Based on the above, it is concluded that there will be no impact on the environment resulting from this change and the change meets the criteria specified in 10 CFR 51.22 for a categorical exclusion from the requirements 10 CFR 51.21 relative to requiring a specific environmental assessment by Commission.
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Attachment IV to WO 99-0001
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ATTACHMENT IV PROPOSED TECHNICAL SPECIFICATION CHANGES CURRENT TECHNICAL SPECIFICATIONS