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1 NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS | 1 NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS | ||
: BACKGROUND: | : BACKGROUND: | ||
I, L ' In a letter dated July 26,1989, (G-89263) the NRC discussed the commitment that Public Service Lompany of Colorado. (PSC). made .to submit a Technical Specification amendment to assure control room habitability.as-long.as gaseous chlorine is used on site. As stated in the letter dated June 16,1989, (P-89218) the PSC commitment was to submit the amendment request by September 30, 1989, and that the proposed amendment will be based on TSUP 3/4.3.2.6 (Chlorine Detector | I, L ' In a {{letter dated|date=July 26, 1989|text=letter dated July 26,1989}}, (G-89263) the NRC discussed the commitment that Public Service Lompany of Colorado. (PSC). made .to submit a Technical Specification amendment to assure control room habitability.as-long.as gaseous chlorine is used on site. As stated in the {{letter dated|date=June 16, 1989|text=letter dated June 16,1989}}, (P-89218) the PSC commitment was to submit the amendment request by September 30, 1989, and that the proposed amendment will be based on TSUP 3/4.3.2.6 (Chlorine Detector | ||
; and Alarm System),'and TSUP 3/4.7.9 (Control Room Emergency Ventilation System). This commitment is based on the requirements of Generic Letter (GL). 83-36 and GL 83-37 concerning control room habitability, which are, in turn, related to the control room habitability requirements of NUREG C'87c The changes being included with this submittal will ensure the operability.of the chlorine detector when a significant amount of gaseosi chlorine. is onsite. This will protect plant personnel by alerting'them to a chlorine leak. Also, the operability of the control room ' emergency ventilation system will be ensured by the proposed Technical Specification amendment. | ; and Alarm System),'and TSUP 3/4.7.9 (Control Room Emergency Ventilation System). This commitment is based on the requirements of Generic Letter (GL). 83-36 and GL 83-37 concerning control room habitability, which are, in turn, related to the control room habitability requirements of NUREG C'87c The changes being included with this submittal will ensure the operability.of the chlorine detector when a significant amount of gaseosi chlorine. is onsite. This will protect plant personnel by alerting'them to a chlorine leak. Also, the operability of the control room ' emergency ventilation system will be ensured by the proposed Technical Specification amendment. | ||
EVALUATION: | EVALUATION: |
Latest revision as of 12:37, 8 March 2021
ML20248G446 | |
Person / Time | |
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Site: | Fort Saint Vrain |
Issue date: | 09/30/1989 |
From: | PUBLIC SERVICE CO. OF COLORADO |
To: | |
Shared Package | |
ML20248G442 | List: |
References | |
NUDOCS 8910100243 | |
Download: ML20248G446 (14) | |
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V ATTACHMENT 2 TO P-89382 PROPOSED CHANGES
'l 8910100243 890930 PDR ADOCK 05000267 p PDC
Fort S't. Vrain #1
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Technical Specifications-Amendment No.
Page 4.4-19 LCO 4.4.7 CHLORINE DETECTION AND ALARM SYSTEM LIMITING CONDITION FOR OPERATION The chlorine detection and alarm system shall be OPERABLE, with a setpoint adjusted to alarm at.a chlorine concentration of 5 ppm or-less.
APPLICABILITY: At all times, when ' gaseous chlorine is onsite except for small quantities as would be used for laboratory testing.
ACTION:
- a. With either the detection or alarm system inoperable:
- 1. Restore the system to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, or
- 2. Close the chlorine cottle discharge valves, except during chlorination. During chlorination, patrol the area once every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
ASSOCIATED SURVEILLANCE REQUIREMENT: SR 5.4.14 BASIS FOR SPECIFICATION LCO 4.4.7 The OPERABILITY of the chlorine detection and alarm system ensures the capability to detect an accidental chlorine release and alert control room personnel.
Isolating the chlorine bottle discharge by closing the discharge
+, valves, and patroling the area once every 2 hours during
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chlorination, will prevent an inadvertent release of chlorine if the chlorine detection and alarm system is inoperable.
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' Fort'St. Vrain 01 L ;< Technical Specifications
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,- Amendment No.
Page 4.4-20 L >
c LCO 4.4.8 CONTROL ROOM EMERGENCY VENTILATION SYSTEM
.1 LIMITING CONDITION FOR OPERATION The control room emergency ventilation system shall be OPERABLE in the recircula M en mode with minimum makeup with:
- a. 'Both the control room emergency filter fan (C-7506) and the
. control room supply fan (C-7504X) OPERABLE, and
- b. The control room emergency makeup ventilation filter (F-7S02)
APPLICABILITY: At all times ACTION: POWER, LOW POWER and STARTUP '
- a. With one of the above required fans (item a.) inoperable, but with control room positive pressure greater than or equal to 0.05 inches water gauge, restore the inoperable fan to OPERABLE status within 7 days or be in SHUTDOWN within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
- b. With one of the above required fans (item a.) inoperable, and control room positive pressure less than 0.05 inches water gauge, restore the inoperable fan to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in SHUTDOWN within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
- c. With the control room emergency makeup ventilation filter (F-7502) (item b.) inoperable restore the filter to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in SHUTDOWN within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
SHU1DOWN and REFUELING With the above requirements for the control room emergency ventilation system not met:
- a. Restore the system to OPERABLE status within 7 days or,
- b. Suspend all operations involving CORE ALTERATIONS, control rod movements resulting in positive reactivity changes, or movement of IRRADIATED FUEL in the PCRV.
ASSOCIATED SURVEILLANCE REQUIREMENT: SR 5.4.15
Fort St. Vrain'#1 Technical Specifications
. Amendment No. ;
Page 4.4-21 i
BASIS FOR SPECIFICATION LCO 4.4.8 _.
i The control' room ventilation system is designed to supply filtered, l recirculated a'ir at a positive pressure with minimum makeup. FSAR Table 7.1-1 specifies that a slight positive pressure is assumed in ;
the analysis of an operating environment. The recirculation. mode !
with minimum makeup, also known as the hi-radiation mode or the 2 minimum makeup mode, isolates the normal makeup and uses the normal control room supply and return fans to recirculate air through the ;
air handling units. Makeup air is taken from the turbine building i and passed through a High Efficiency Particulate Air (HEPA) filter and a charcoal adsorber thereby ensuring that control room personnel airborne radiation exposures during and following all credible ;
accident conditions will not exceed 10 CFR 20 limits.
A 72-hour ACTION time associated with an inoperable control room emergency makeup ventilation filter (F-7502) is acceptable based on j the fact that it is in service only when the control room ventilation i system is.in the minimum makeup mode. During normal control room j ventilation, air is drawn from outside and bypasses the filter. In (
the event that the filter (F-7502) is inoperable and the control room l ventilation system is in the minimum makeup mode, a backup source of !
air is provided to operators, if required, via the breathing air j system. !
The 7-day ACTION time sr.ecified is consistent with LWR Standard Technical Specifications, LC0 3.7.7. ,
The control room pressure can be maintained at a positive pressure of '
at least 0.125 inches water gauge in the recirculation mode with emergency makeup, with both the emergency filter fan and the supply fan operating. If either of these fans becomes inoperable, control room ' pressure can still be maintained positive, by shutting off the control rcom return fan and closing the toilet exhaust damper, in which case a positive pressure of at least 0.05 inches water gauge is !'
provided. The channel accuracy for measuring control room pressure is 2*J or less of the instrument range which is 2 inches. Thus, 0.04 !
inches water ' gauge may be assumed for total channel accuracy. !
Specifying a control room pressure of at least 0.05 inches water l gauge as the surveillance requirement ensures positive pressure in ,
the control room even in the event of a failure of one of the two !
required fans in the emergency ventilation line-up. Thus, the FSAR l assumptions are verified through required surveillance. (FSAR l Section 11.2.2 and Appendix C. Criterion 11). l The assumptions relative to control room positive pressure assume the access door to the control room is closed. However, due to plant !
security reasons, the access door may be opened and personnel access ;
controlled by a full-time guard. In the event of an emergency, the door will be closed to ensure that a positive control room pressure is maintained.
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Fort St. Vrain #1
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Technical Specifications
. Amendment No.
Page 5.4-17 SPECIFICATION SR 5.4.14 - CHLORINE DETECTION AND ALARM SYSTEM SURVEILLANCE REQUIREMENT _,.
l-The chlorine detection and alarm system shall be demonstrated OPERABLE whenever LCO 4.4.7 is applicable by:
l a. At least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, by performing a CHANNEL CHECK, l
l b. At least once per 31 days, by performing a CHANNEL TEST, e.nd l
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- c. At least once per 18 months, by performing a CHANNEL CALIBRATION.
1 ASSOCIATED LCO: LCO 4.4.7 BASIS FOR SPECIFICATION SR 5.4.14 l The SURVEILLANCE INTERVAL specified for this instrumentation is consistent with LWR Standard Technical Specifications, Surveillance Requirement 4.3.3.7, and ensures proper operation in the event of an accidental chlorine release.
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Fort St. Vrain #1 Technical Specifications
, Amendment No.
Page 5.4-18 3
SPECIFICATION SR 5.4.15 CONTROL ROOM EMERGENCY VENTILATION SYSTEM SURVEILLANCE REQUIREMENT The control room emergency ventilation system shall be demonstrated OPERABLE:
- a. At least once per 31 days, by initiating, from the control room, flow through the High Efficiency Particulate Air (HEPA) filters and charcoal adsorbers and verifying that the system operates for at least 10 continuous hours.
- b. At -least once per 18 months, or after any structural maintenance on the HEPA filter or chercoal adsorber housings, or following painting, fire, or a chemical release in any ventilation zone communicating with the system by:
- 1. Verifying that the ventilation system satisfies the in place penetration and bypass leakage testing acceptance criteria of less than 0.05% and uses the test procedure guidance in Regulatory Positions C.5.a. C.S.c and C.5.d of Regulatory Guide 1.52, Revision 2, March 1978, and the system flow rate is greater than or equal to 450 ACFM.
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- 2. Verifying within 31 days after removal, that a laboratory analysis of a representative carbon sample obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, March 1978, meets the criteria of Regulatory Position C 6.a of Regulatory Guide 1.52, Revision 2, March 1978, for a methyl iodine penetration of less than 3% at 30 degrees C, 95% RH.
- 3. Verifying a system flow rate of greater than or equal to 450 ACFM during system operation when tested in accordance with ANSI N510-1975.
- c. After every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of charcoal adsorber operation by verifying l within 31 days after removal, that a laboratory analysis of a representative carbon sample obtained in accordance with Regulatory Position C.6.b of Regulatory Guide 1.52, Revision 2, o March 1978, meets the laboratory testing criteria of Regulatory Position C.6.a of Regulatory Guide 1.52, Revision 2, March 1978, for a methyl iodide penetration of less than 3% at 30 degrees C, 955 RH.
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l Fort St. Vrain #1 Technical Specifications
,- Amendment No.
Page 5.4-19
- l. SPECIFICATION 5.4.15 (Continued) l d. At least once per 18 months by:
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- 1. Verifying that the pressure drop across the HEPA filters and charcoal adsorbers is less than 6 inches of water while operating the system at a flow rate of greater than or equal to 450 ACFM.
- 2. Verifying that on a simulated signal indir.ating high l radiation in the reactor building ventilation- exhaust, the l system automatically switches into the recirculation mode l with minimum makeup.
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- 3. Verifying that the control room emergency ventilation system maintains the cortrol roo;n at a positive pressure in the following configurations:
a) With both the emergency filter fan and the control room supply fan OPFRABLE, maintain at least 0.125 inches water gauge pressure.
b) With either the emergency filter fan or the control room supply fan inoperable, maintain at least 0.05 inches water gauge pressure.
- e. After each complete or partial replacement of a HEPA filter bank verify that the HEPA filter bank satisfies the in place penetration and bypass leakage testing acceptance criteria of l less than'O.05"; in accordance with ANSI N510-1975 for a DOP test I aerosol while operating the system at a flow rate greater than or equal to 450 ACFM.
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- f. Af ter each complete or partial replacement of a charcoal adsorber bank verify that the charcoal adsorber Dank satisnes the in-l place penetration and bypass leakage testing acceptance criteria l of less than 0.05"; in accordance with ANSI N510-1975 for a
! halogenated hydrocarbon refrigerant test gas while operating the l system at a flow rate of greater than or equal to 450 ACFM.
1 ASSOCIATED LCO: LCO 4.4.8
Fort St. Vrain #1 Technical Specifications
- Amendment No.
Page 5.4-20 i
BASIS FOR SPECIFICATION SR 5.4.15 _
Ensuring that an excessive pressure drop does not exist across the emergency makeup filter demonstrates that the filters and adsorbers are not clogged and that the. control room pressure can be maintained po sitive. The specified surveillance tests are adequate to ensure system OPERABILITY under normal and abnormal conditions. Normal makeup requirements to maintain a slight positive pressure in the control room have been calculated to be 450 ACFM. That is, 450 ACFM, is enough to ensure that a positive reading on the control room pressure gauge exceeds the maximum channel accuracy.
The addition of these surveillance requirements is in response to NUREG-0737, Item III D.3.4. The Surveillance Requirements and SURVEILLANCE INTERVALS specified are consistent with LWR Standard Technical Specifications, Surveillance Requirement 4.7.7.
If fire, chemical release, or painting, occurs such that the HEPA filter or charcoal adsorber could become significantly contaminated from the fumes, chemicals, or foreign materials, the same tests and sample analysis should be performed, as required, for operational surveillance. Control room emergency ventilation system OPERABILITY should be verified per item b. following:
- 1. Painting with greater than 5 gallons of paint which could reasonably be expected to interfere with the charcoal to adsorb methyl iodide,
- 2. Any spray (aerosol generating) painting which could reasonably be expected to interfere with the charcoal to adsorb methyl iodide,
- 3. Fires that exceed 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in duration, or
- 4. Any uncontrolled release / spillage of 5 gallons or more of any chemical material which could reasonably be expected to interfere with the charcoal to adsorb methyl iodide.
A pressure drop across the combined HEPA filter and charcoal adsorber of less than 6 inches of water gauge at the filter design flow rate will indicate that the filters and adsorbers are not clogged by excessive amounts of foreign matter.
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ATTACHMENT 3' TO P-89382 NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS
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1 NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS
- BACKGROUND:
I, L ' In a letter dated July 26,1989, (G-89263) the NRC discussed the commitment that Public Service Lompany of Colorado. (PSC). made .to submit a Technical Specification amendment to assure control room habitability.as-long.as gaseous chlorine is used on site. As stated in the letter dated June 16,1989, (P-89218) the PSC commitment was to submit the amendment request by September 30, 1989, and that the proposed amendment will be based on TSUP 3/4.3.2.6 (Chlorine Detector
- and Alarm System),'and TSUP 3/4.7.9 (Control Room Emergency Ventilation System). This commitment is based on the requirements of Generic Letter (GL). 83-36 and GL 83-37 concerning control room habitability, which are, in turn, related to the control room habitability requirements of NUREG C'87c The changes being included with this submittal will ensure the operability.of the chlorine detector when a significant amount of gaseosi chlorine. is onsite. This will protect plant personnel by alerting'them to a chlorine leak. Also, the operability of the control room ' emergency ventilation system will be ensured by the proposed Technical Specification amendment.
EVALUATION:
PSC has evaluated the proposed amendment request for significant hazards consideration using the standards in Title 10, Code of Federal Regulations, Part 50.92. The proposed amendment request involves no significant hazards, since the proposed amendment would not:
- 1. . Involve a significant increase in the probability or consequences of an accident previously evaluated.
The addition of LCO's 4.4.7 and 4.4.8, and SR's 5.4.14 and 5.4.15 improve the Fort St. Vrain Technical Specifications in terms of personnel safety and control room habitability.
LCO's 4.4.7 and 4.4.8 (and their associated Surveillance l
Requirements) are based upon, and are very similar to TSUP's 3/4.3,2.6 and 3/4.7.9, respectively which were previously reviewed by the NRC in G-89145. Furthermore, the PSC commitment to the NRC in terms of the chlorine gas detection and control room emergency ventilation system issues was to submit proposed amendments based on the latest draft TSUP f' for this equipment. This submittal is intended to address i these issues and close the commitment as identified in P-I 89218, as reiterated in G-89263. The differences between TSUP for these systems and this submittal are discussed and evaluated below.
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NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS (CON'T.)
LCO 4.4.7 has minor reformatting changes to make it more consistent with the' current Technical' Specification format.
This does not impact the intent of the LCO.
l The APPLICABILITY Statement has been revised for clarification. TSUP LCO 3.3.2.6 was applicable when chlorine gas is onsite for the purpose of chlorination.
This had the potential to be misleading because if there were chlorine on site for any reason other than chlorination, the LCO would not have applied, though the ,
possibility for .a chlorine release would still exist. I Therefore, LCO 4.4.7 applies whenever gaseous chlorine is !
.onsite- in quantities greater than the small amount that.
would be used in laboratory testing. This revision is both clarifying and more conservative. As such, it enhances the usefulness of the LCO.
The Action Statement.that specified that the provisions of Specification 3.0,.4 are not applicable was deleted. The reason for this is that Specification 3.0.4 is unique to the TSUP and does not exist in any form in the current Technical Specifications. Thus, there is no need to specify that a non-existent Specification does not apply.
The BASIS for LCO 4.4.7 has been revised by deleting the statement that control room personnel may initiate protective actions to maintain control room habitability upon being alerted to an accidental chlorine release.
Though the chlorine detector will alarm and therefore alert personnel to the presence of gaseous chlorine, there are no specific actions- to take to maintain control room habitability. The safest and best thing for the control room personnel to do is to leave the ventilation system unchanged, in its normal mode of operation. The intake in this mode is at the top of the reactor building, and because chlorine gas is heavier than air, it is much less likely that chlorine gas could enter the control room than if the emergency ventilation system were actuated. In this mode, the intake is drawn at a lower elevation making it more likely that the chlorine gas could be drawn into the control room. Though the air intake is passed through a HEPA and charcoal filter, it is not desirable to unnecessarily place them in service. Therefore, the best action in the event of an accidental chlorine gas release is to have the control room personnel alerted so that they can advise all plant personnel of the situation. As such, the deletion of the phrase implying that there are protective actions the control room personnel should initiate to maintain control habitability upon receiving the chlorine detector alarm is
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NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS (CON'T.)
an improvement to the BASIS. This revision is a clarification and thus, will enhance the safety associated with the use of LCO 4.4.7.
LCO 4.4.8 has minor format changes from TSUP LCO 3.7 9.
This reformatting makes LCO 4.4.8 more consistent with the current Technical Specifications. This means that LCO 4.4.8 will be easier for plant personnel to use, and is, as such, an enhancement.
Action Statement b. under SHUTDOWN and REFUELING has been revised by clarifying that the movement of IRRADIATED FUEL in the PCRV shall be suspended if the control room emergency ventilation system is not operable. The words 'in the PCRV' were added to make clear that fuel movement outside of the PCRV need not be suspended if the emergency ventilation system is inoperable. This is because the reactor plant ventilation system (as discussed in FSAR Sections 6.2.2, 6.2.3.2, and D.I.3.4.2) is capable of handling any radiation or contamination problems that could occur on the fuel deck, with the fuel handling machine, or on the fuel loading and shipping port. If there were an event leading to . radiation or contamination in the reactor plant, the reactor building ventilation system is designed to ensure that there would not be a significant release of airborne radiation to atmosphere. This being the case, the air intake to the control room would not pose a threat to control room habitability even if it were not first passed through the HEPA filter and charcoal adsorber. Therefore, the addition of the words 'in the PCRV' is a clarification that will eliminate the unnecessary suspension of activities that could in no way affect control room habitability. Since this clarification has no adverse affect on control room habitability, clarifies the intent of the Action Statement, and will prevent the unnecessary halting or hindering of plant activities, it is an enhancement to LC0 4.4.8.
In the BASIS for LCO 4.4.8, the reference to a prefilter was removed. When TSUP 3/4.7.9 was prepared, it was planned that a prefilter would be included in the control room emergency ventilation system. However, it was subsequently determined that it was not required. The full evaluation of this decision can be found in the safety evaluation for DCN-313. Basically, it was determined that since the suction is taken from the turbine building, not directly from outside air, no prefilter is needed.
The statement that the 7-day Action time specified in the Action Statement is consistent with the LWR Standard
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NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS (CON'T.)
L Technical Specifications was 'added' to the BASIS section.
l This addition is to explain the interval and to provide _the-I basis for its' choice. This explanation did not exist in the TSUP 3/4.7.9 BASIS,.though the 7-day Action time did. As such, this addition is an enhancement to the BASIS.
The last sentence of the last paragraph of the BASIS implied that plant operating procedures existed which required the control room door to remain closed under certain circumstances. This is not currently the case at Fort St.
Vrain. The door's will be closed by administrative control during an emergency. Thus, the deletion of the phrase 'as required by plant operating procedures' in reference to the control door being closed is a correction to the BASIS.
Surveillance Requirement (SR) 5.4.14 is based on, and is similar to TSUP SR 4.3.2.6. Since the TSUP format presents the LCO and associated SR together, it is clear that the APPLICABILITY applies to both. The format of the current Technical Specification and the amendments proposed herein separates the LCO and associated SR. The phrase 'whenever LCO 4.4.7 is applicable' was added to SR 5.4.14 to clarify that they are applicable at the same time, under the same circumstances. This concept is clear in the TSUP format and this phrase was added to make it equally clear in the format of this proposed amendment.
Added to the BASIS for SR 5.4.14 is the LWR Standard Technical Specification section reference. This is a detail that only serves to enhance the BASIS, and does not change its intent.
SR 5.4.15 is new to the existing Technical Specifications, but is based on and nearly identical to TSUP SR 4.7.9, except for minor formatting changes to make it more consistent with the existing Technical Specifications.
A stateinent was added to the BASIS for SR 5.4.15 to explain that the Surveillance Requirements and SURVEILLANCE INTERVALS specified in the SR are consistent with the LWR Standard Technical Specifications. Also added to the BASIS of SR 5.4.15 is the discussion about the HEPA filter in the presence of paint and other chemicals that could communicate with the filter. This was added to clarify and qualtify Surveillance Requirement item b. These criteria were developed based on plant operating experience. This is explanatory in nature and was not included in the TSUP 3/4.7.9 basis and is consistent with the TSUP 3/4.5.2 Basis.
Therefore, thi' is an enhancement to the BASIS.
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NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS'(CON'T.)
For the reasons. providedL with the discussions of the t changes, these revisions do not involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2. Create the: possibility of a new or different. kind of accident from any accident previously evaluated.
As described above, no change is. being made to plant I._ operation or safety: systems that could -adversely impact-plant or personnel safety.
- 3. Involve a significant reduction in a margin of safety.
No ' margins of safety are.being impacted or reduced by this-proposal, as discussed above.
CONCLUSION:
Based on the above evaluation, it is concluded that operation of Fort St. Vrain in accordance with the proposed changes will involve no significant hazards consideration. PSC considers the proposed changes ~to improve overall personnel safety. The proposed amendments have. been previously reviewed by the NRC during the.TSUP review process, except for the revisions which are all described and evaluated above.
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