HL-5213, Application for Amends to Licenses DPR-57 & NPF-5,clarifying Applicability of Certain Surveillances Addressing Rvp & Temp Limits & Replacing Vessel Pressure & Temp Limit Curves W/New Curves

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Application for Amends to Licenses DPR-57 & NPF-5,clarifying Applicability of Certain Surveillances Addressing Rvp & Temp Limits & Replacing Vessel Pressure & Temp Limit Curves W/New Curves
ML20113F550
Person / Time
Site: Hatch  Southern Nuclear icon.png
Issue date: 09/19/1996
From: Beckham J
GEORGIA POWER CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20113F553 List:
References
HL-5213, NUDOCS 9609240349
Download: ML20113F550 (11)
v • d • e


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Georgia Power company 40 inverness Center Parkway Post Office Box 1895 Birmingham, Alabama 35201

! Telephone 205 877 7279 A

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l J. T. Beckham, Jr. . k. GeorpiaPower i

Vice President - Nuclear o j Hatch Project . te sauerrn abctnc systorn September 19, 1996 l Docket Nos. 50-321 HL-5213 L 50-366 t l

l U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555 f Edwin I. Hatch Nuclear Plant L Request to Revise Technical Specifications:

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! Eressure and Temperature Limits

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Gentlemen:

j '. . In accordance with the provisions of 10 CFR 50.90, as required by 10 CFR .50.59(c)(1),  !

j Georgia Power Company (GPC) hereby proposes changes to the Plant Hatch Unit I and  ;

i Unit 2 Technical Specifications, Appendix A to Operating Licenses DPR-57 and NPF-5,  !"

l respectively. The following changes to TS 3.4.9 are proposed-I l

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1. Clarify the Applicability of certain Surveillances addressing reactor v2ssel pressure

. and temperature limits.

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2. Replace the vessel pressure and temperature limit curves with new curves.  !

Enclosure 1 provides a description of the proposed changes, an explanation and l justification for the changes, and the circumstances necessitating the changes. Enclosure 2 )

describes GPC's determination that the proposed changes do not involve a significant hazards consideration.' Enclosure 3 provides page change instructions for incorporating the proposed Technical Specifications pages, as well as the revised Technical Specifications pages and the associated markups of the existing pages. The revised Bases associated with the proposed Technical Specifications changes are provided, for your information, following Enclosure 3. Enclosure 4 provides General Electric report GENE-523-A137-1295,"E. I. Hatch Nuclear Power Station, P-T Curve Modification for i Unit I and Unit 2," which supports the proposed Technical Specifications revisions.

l To support the upcoming Unit 2 refueling outage, GPC requests the NRC review and

. approve the amendment no later than March 1,1997. GPC also requests that, once the amendment is approved, it be issued with an immediate effective date, with j% I implementation no later than 30 days after issuance. l 9609240349 960919 PDR ADOCK 05000321 P PM l'

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GeorgiaPower d U.S. Nuclear Regulatory Commission Page 2 September 19, 1996 '

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In accordance with the requirements of 10 CFR 50.91, a copy of this letter and all  ;

applicable enclosures will be sent to the designated State oflicial of the Environmental  !

Protection Division of the Georgia Department of Natural Resources. -

Mr. J. T. Beckham, Jr. states he is Vice President of Georgia Power Company and is authorized to execute this oath on behalf of Georgia Power Company, and to the best of his knowledge and belief, the facts set forth in this letter are true. i Sincerely,

'0 ,

. T. Beckham, Jr. I 1

i Sworn to andsubscribed before me this _]Yday of % ym ,1996.

de 4%w~ Notary Public h.gyf.cfh 2. . .., ,(',7, OCV/eb  ;

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Enclosures:

1. Description of and Justification for Proposed Changes l
2. 10 CFR 50.92 Evaluation
3. Page Change Instructions atd Revised Technical Specifications Pages
4. General Electric Report GENE-523-A137-1295 cc: Georeia Power Company Mr. H. L. Sumner, Nuclear Plant General Manager NORMS U.S. Nuclear Remdatorv Commission. Il'ashington. D.C. j Mr. K. Jabbour, Licensing Project Manager - Hatch U.S. Nuclear Remdatorv Commission. Region H Mr. S. D. Ebneter, Regional Administrator Mr. B. L. Holbrook, Senior Resident Inspector - Hatch t

St_me ofGeoreia Mr. J. D. Tanner, Ccmmissioner - Department of Natural Resources IIL-5213 I

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l l Enclosure 1 l

Edwin I. Hatch Nuclear Plant Request to Revise Technical Specifications:

Pressure and Temperature Limits j Descriotion of Chance I

Georgia Power Company (GPC) proposes to revise the Plant Hatch Unit 1 and Unit 2 ,

Technical Specifications requirements for reactor vessel pressure and temperature (P/T)  !

limits. Changes are proposed to Units 1 and 2 Surveillance Requirements (SRs) 3.4.9.1, 3.4.9.2,3.4.9.3,3.4.9.4,3.4.9.5,3.4.9.6, and 3.4.9.7, and to corresponding Units 1 and 2 Figures 3.4.9-1, 3.4.9-2, and 3.4.9-3, which show P/T limit curves for inservice leak and hydrostatic testing, non-nuclear heatup and cooldown, and criticality, respectively.

The changes are intended to clarify the Applicability of the above-mentioned Surveillance Requirements. The proposed changes are necessary to preclude confusion which can and I has occurred during past refueling outages while attempting to implement these Surveillance Requirements. The P/T cunes are being changed to allow separate monitoring of the three major regions of the RPV (i.e., the upper vessel and flange region, the beltline region, and the bottom head region) and to extend the validity of the Unit I curves to 32 Effective Full Power Years (EFPY). Separate monitoring will alleviate the difliculties with meeting certain temperature requirements due to the artificial limits imposed by the current P/T curves.

1 In support of the proposed changes, General Electric (GE) prepared and issued GENE-523-A137-1295, "E. I. Hatch Nuclear Power Station, P-T Curve Modification for Unit I and Unit 2," which is provided in Enclosure 4.

l PROPOSED CHANGES Proposed Chance to SR 3.4.9.1 This Surveillance Requirement specifies the monitoring of Reactor Coolant System (RCS)

Pff limits, and heatup and cooldown rates. The proposed change incorporates the Note into the Surveillance portion of SR 3.4.9.1. The Note to SR 3.4.9.1 states the Surveillance is "Only required to be performed during RCS heatup and cooldown operations and RCS inservice leak and hydrostatic testing." The Note implies that, although the Surveillance Requirement only has to be performed during RCS heatup and cooldown operations and RCS inservice leak and hydrostatic testing, the Surveillance Requirement must be met at all times ("at all times" being the Applicability of LCO 3.4.9.)

l This implication is not true. Figures 3.4.9-1 and 3.4.9-2 apply to the conditions of the reactor vessel unde. going pressure tests and for non-nuclear heatup and cooldown IIL-5213 El-1

_ _ _ _ _. ~ _. _ _ __, _ __._ _ ___.- _ _ _ _ _ _.m _ .._ _ _ ,

o e Enclosure 1 Request to Revise Technical Specifications:

Pressure and Temperature Limits Description ofChange

operations, respectively. During normal operations (with the reactor critical),

l Figure 3.4.9-3 applies. Also, the current Surveillance Requirement can be interpreted to mean that Figures 3.4.9-1 and 3.4.9-2 apply to nuclear heatup operations. This interpretation is not true. These figures apply to non-nuclear P/T changes. Other

! requirements cover nuclear heatup. The proposed change revises SR 3.4.9.1 to state that j part "a" is applicable to non-nuclear heatup and cooldown, and part "b" is apr' c<ble to

! any heatup and cooldown.

l GENE-523-A137-1295 (Enclosure 4) provides explicit guidance on the conditions under i which each Surveillance Requirement and curve applies. The Surveillance Frequency l remains the same.

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Proposed Channe to SR 3.4.9.2

! This Surveillance Requirement provides the reactor P/T limits for criticality. The proposed change adds a Note to SR 3.4.9.2 stating the requirement is "Only required to be met when the reactor is critical and immediately prior to control rod withdrawal for the purpose of achieving criticality."

This proposed change is necessary to clarify the Applicability of the requirement. Adding the Note will avert confusion during the times the reactor is not critical. The Surveillance Frequency remains the same. Also, GPC proposes to change the words in the Frequency i column by specifying," prior to initial control rod withdrawal." The proposed wording

ensures the temperature is confirmed prior to withdrawal of the first rod in the control rod l sequence, not prior to withdrawal of the control rod which will induce criticality.

l- Proposed Channe to SRs 3.4.9.3 and 3.4.9.4 These Surveillance Requirements provide the reactor coolant differential temperature

requirements prior to starting an idle recirculation pump. The proposed change revises the l Surveillance Frequency from "15 minutes" to "Once within 15 minutes of starting an idle l recirculation pump."

l The revised wording is more concise and ensures that the temperature differentials are verified prior to pump start. Also, this proposed change is consistent with the intent of SRs 3.4.9.3 and 3.4.9.4, as described in the Bases.

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HL-5213 El-2

o e Enclosure 1 Request to Revise Technical Specifications:

Pressure and Temperature Limits Description of Change l

Proncsed Change to SR 3.4.9.5 This Surveillance Requirement requires the verification of vessel flange and head flange temperatures while the reactor head is being tensioned. The Note to SR 3.4.9.5 states the Surveillance is "Only required to be performed when tensioning the reactor vessel head l bolting studs." The proposed change revises the Note by changing " performed" to " met" and adding the word "detensioning." Also, the Frequency is changed to more clearly delineate when the SR is to be performed.

GENE-523-A137-1295 (Enclosure 4) clearly identifies the Applicability of SR 3.4.9.5 as the time when the RPV head is being tensioned or defensioned.

The basis for changing " performed" to " met" is the same as previously described in the Proposed Change to SR 3.4.9.1. Adding the word "detensioning" ensures no misunderstanding of the specification involving tensioning versus detensioning operations.

SR 3.4.9.5 is applicable while detensioning and tensioning the head. The Surveillance l Frequency remains the same.

Proposed Channes to SR 3.4.9.6 and SR 3.4.9.7 These Surveillance Requirements provide the temperature requirements for the reactor -

vessel flange and head flange with the head tensioned. The proposed change deletes SR 3.4.9.7 and combines it with SR 3.4.9.6. The Note in Unit 1 SR 3.4.9.6 is changed from "Not required to be performed until 30 minutes after RCS temperature 5 86 F in MODE 4" to "Only required to be met when the reactor vessel head is tensioned." (The Unit 2 Note is similarly changed.) The requirements of the current Notes for SRs 3.4.9.6 and 3.4.9.7 are incorporated into the Frequency column of SR 3.4.9.6.

GENE-523-A137-1295 (Enclosure 4) clearly indicates the conditions of SR 3.4.9.6 apply when the reactor pressure vessel (RPV) head is tensioned. Deleting SR 3.4.9.7 does not result in the removal of any surveillance checks, since the requirements are entirely l incorporated into SR 3.4.9.6. The Surveillance Frequencies remain the same.

Proposed Chanees to Figures 3.4.9-L 3.4.9-2 and 3.4.9-3 l

l The proposed change replaces the current P/f curves with new curves generated as part of GE's evaluation contained in GENE-523-A137-1295. The new curves extend validity l on Unit I to 32 EFPY, and for inservice leak and hydrostatic testing, and heatup and cooldown, allow monitoring the bottom head separately from the upper vessel and beltline r

HL-5213 El-3 1

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l Enclosure 1 l Request to Revise Technical Specifications:

Pressure and Temperature Limits Description of Change l regions. Also, the Unit I criticality curve is revised to account for a 10 CFR 50,

! Appendix G, requirement not previously accounted for in the current Unit I curve. The l new curves, including the criticality curve, account for irradiation embrittlement effects on the beltline region, as well as the effects of the recently uprated power level.

JUSTIFICATION FOR CIIANGES As stated previously, the proposed Technical Specifications changes are based on GE report GENE-523-A137-1295, issued to Plant Hatch in May 1996. The GE report, included as Enclosure 4 of this submittal, clearly defmes the temperature limits of each region (vessel bottom head, beltline, and upper vessel) of the RPV for each of the following four conditions:

Condition 1. The head is either off or on, but is not tensioned; i.e., no potential for pressurization.

Condition 2. The head is being either tensioned or detensioned.

Condition 3. The head is tensioned, but there is no pressure and no heatup or cooldown.

Condition 4. The vessel is undergoing a pressure test, non-nuclear heatup/cooldown, or critical operations.

Conditions 1,2, and 3 occur with very low pressure in the RPV.

The proposed changes to SRs 3.4.9.1, 3.4.9.2, 3.4.9.3, 3.4.9.4, 3.4.9.5, 3.4.9.6, and 3.4.9.7 address low pressure conditions and are intended to clarify the applicable conditions for these Surveillance Requirements. The proposed changes do not relax actual limits or reduce Surveillance Frequencies. Furthermore, Conditions 2,3, and 4 listed above for the RPV have specific operating limits which are monitored, and will continue to be monitored, via specific Technical Specifications Surveillance Requirements.

Temperature limitations for Condition I are specified in the Bases.

The current Technical Specifications for low pressure conditions can be misinterpreted in an overly conservative manner as discussed below:

1. In situations where the RPV head is being either tensioned or detensioned, the Note for current SR 3.4.9.5 states that the Surveillance must be " performed" whenever l the head is being tensioned. This statement can be misinterpreted to mean that, while the Surveillance is only required to be performed when head tensioning is in HL-5213 El-4

, s Enclosure 1 Request to Revise Technical Specifications:

Pressure and Temperature Limits Description of Change progress, it must be met at all times ("at all times" being the Applicability of LCO 3.4.9). This is not true. SR 3.4.9.5 is the precise requirement for the condition of the RPV head being tensioned or detensioned. Similarly, there are precise P/T requirements for Conditions 3 and 4 above.

2. Current SR 3.4.9.1 attempts to define the requirements for pressure tests, and RCS heatup and cooldown. The monitoring of Figures 3.4.9-1 and 3.4.9-2 is required every 30 minutes during pressure tests, and RCS heatup and cooldown operations, respectively. The Surveillance Requirement also requires ensuring heatup and cooldown operations are < 100 F in any 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> period. However, the wording of the Note for SR 3.4.9.1 can be interpreted to mean that Figures 3.4.9-1 and 3.4.9-2 must be adhered to during a nuclear heatup. This interpretation is not tme.

Figures 3.4.9-1 and 3.4.9-2 show the precise requirements for pressure tests, and non-nuclear heatup and cooldown operations. Nuclear heatup operations are covered by the 100 F change in any I hour period requirement, SR 3.4.9.2, and the criticality curve shown in Figure 3.4.9-3.

3. SRs 3.4.9.2,3.4.9.6, and 3.4.9.7 can similarly be interpreted in an overly conservative manner. Current SR 3.4.9.2 has no modifying Note to qualify its Applicability. As a result, the Surveillance Requirement could be interpreted as being applicable at all times. SR 3.4.9.2 is clearly applicable only during critical operations, as described in GE report GENE-523-A137-1295 (Enclosure 4).

SRs 3.4.9.6, and 3.4.9.7 could be misinterpreted because of previously discussed differences between the words " performed" and " met" To ensure the Surveillance is met during criticality, the Note also states that 3R 3.4.9.2 must be met immediately prior to achieving criticality.

The Frequencies for SRs 3.4.9.4 and 3.4.9.5 are being revised to clarify that the Surveillance is to be performed prior to restarting the recirculation pump.

Unit I and Unit 2 TS 3.4.9 provides appropriate Surveillance Requirements to ensure compliance with the applicable limits for Conditions 2,3, and 4 described above. The proposed changes clearly define the Applicability of each Surveillance Requirement to preclude confusion during future outages.

The proposed changes to the operating curves shown in Figures 3.4.9-1, 3.4.9-2, and j 3.4.9-3 represent the potentially pressurized conditions. The updated figures account for {

operation to 32 EFPY for the Unit I curves and provide an additional operational margin j in that the requirements for the upper vessel, beltline, and bottom head regions are separated for the inservice leak and hydrostatic testing curve, and the heatup and cooldown curve. The current figures are composites of the three regions. Thus, a specific l

HL-5213 El-5

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Enclosure 1 Request to Revise Technical Specifications:

Pressure and Temperature Limits Description of Change l

l point on a curve represents the most limiting point for the three regions. By separating the curves for the three regions for Figures 3.4.9-1 and 3.4.9-2, artificial restrictions for the  !

non-limiting regions at a specific point are eliminated. Separating the regions for the l

criticality curve shown in Figure 3.4.9-3 failed to yield significant benefits and thus, was  ;

not done. For the criticality curve (Figure 3.4.9-3) Title 10 CFR 50, Appendix G, requires i vessel temperature to be 40 F above any limits for the pressure test curve or the non-  !

nuclear heatup a d cooldown curve. Also, it requires the temperature to be at least as  ;

l high as the permissible temperature for the inservice system hydrostatic pressure test. The )'

current Unit I criticality curve (Figure 3.4.9-3) does not account for this requirement. As a result, the new criticality curve contains a step change at 312 psig.  !

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t HL-5213 El-6

a e Enclosure 2 Edwin I. Hatch Nuclear Plant Request to Revise Technical Specifications:

Pressure and Temperature Limits 10 CFR 50.92 No Significant Hazards Evaluation In 10 CFR 50.92(c), the NRC provides the following standards to be used in determining the existence of a significant hazards consideration:

...a proposed amendment to an operating license for a facility licensed under 50.21(b) or 50.2'2for a testing facility involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not: (1) Involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) Create the possibility of an accident of a new or different kind from any previously evaluated; or (3)

Involve a significant reduction in the margin of safety.

Georgia Power Company has reviewed the proposed license amendment request and determined its adoption does not involve a significant hazards consideration based on the following discussion.

Basis for no sienificant hazards consideration determination l

1. Does the change im>oh'e a sigmficant increase in the probability or consequences of an accidentpreviously emhiated?

Pressure and temperature (P/T) limits for the reactor pressure vessel (RPV) are established to ensure brittle fracture of the vessel does not occur.

A. The proposed changes merely clarify the Applicability of the P/T limits for each of the low pressure conditions by replacing the word " performed" with " met",

adding Notes to Surveillance Requirements, incorporating the requirements of Notes into the Surveillance Requirements, and modifying the Frequency statements. Conditions 2,3, and 4, discussed in Enclosure 1 " justification of changes", have their own Surveillance Requirements. Temperature requirements for Condition 1 are specified in the Bases. This proposed change only clarifies which Surveillance Requirement applies to each operating configuration. No reduction in Surveillance Frequencies is proposed.

B. The proposed revisions to the operating limits curves for inservice leak and hydrostatic testing, and the heatup and cooldown allow independent monitoring of the three RPV regions; i.e., the bottom head, the upper vessel and flange, and the core beltline. The three Unit I curves, including the criticality curve, were extended to 32 Effective Full Power Years (EFPY), and a correction to the HL-5213 E2-1

i Enclosure 2 ,

Request to Revise Technical Specifications:

Pressure Temperature Limits 10 CFR 50.92, No Significant Hazards Evaluation Unit I criticality curve was made. Operating limits for each of the curves were evaluated in accordance with the methodology given in the applicable ASME Codes; Regulatory Guide 1.99, Rev. 2, and Appendix G of 10 CFR 50.

The actual lim;ts in the inservice leak and hydrostatic testing curves, and the heatup and cooldown curves were not relaxed. Therefore, segregating the curves into the three affected vessel regions does not represent a reduction in the actual P/T requirements. The current P/T curves represent a composite of the three regions, with each point representing the limiting region. Regions of the vessel that are not limiting at a specific point are, therefore, artificially restrained.

Upon implementation of the proposed changes, each vessel region will have its own curve, with its own true limit.

Since the proposed changes do not affect the recirculation piping, the probability and the consequences of a loss of coolant accident are not increased. Likewise, no other previously evaluated accidents or transients, as defined in Chapters 14 and 15 of the Units 1 and 2 Final Safety Analysis Reports, are affected by the proposed changes.

In summary, the proposed changes do not represent a relaxation of any actual operating limit and do not reduce the Frequency of any Surveillance. Three of the four operating configurations of the RPV are covered by Surveillance Requirements.

Temperature limitations for the head removed from the vessel are given in the Bases. ,

The operating limits were developed using the approved methodology contained in l

10 CFR 50, Appendix G. Therefore, the probability and consequences of a brittle fracture of the RPV are not increased.

2. Do the proposed changes create the possibility ofa new or different type ofaccident from anypreviously evaluated.

Implementing the low pressure changes, or the new operating limit curves, does not alter the design or operation of any system designed for the prevention or mitigation of accidents. The proposed changes do not introduce any new type of normal or abnormal operating mode or failure mode. All P/T limits for the Unit I and the Unit 2 reactor vessels continue to be monitored per the requirements of 10 CFR 50, j Appendices G and H. Therefore, the proposed changes do not create the possibility of a new type of accident.

HL-5213 E2-2

a :  ;

Enclosure 2

  • Request to Revise Technical Specifications:

l Pressure Temperature Limits '

10 CFR 50.92, No Significant Hazards Evaluation 1

3. Do the proposed changes invoh e a sigmficant reduction in the margin ofsafety?

The purpose of the P/T limits is to ensure a brittle fracture of the RPV does not occur.

The proposed Technical Specifications changes for the low pressure conditions are ,

made for clarification purposes. No operating limits or Surveillance Requirements are l relaxed. The wording of current Technical Specifications SRs 3.4.9.1,3.4.9.2, l

3.4.9.5,3.4.9.6, and 3.4.9.7 could result in overly conservative application of the

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requirements. The proposed amendment is written to remove the ambiguity in that the l Applicability and Frequency of each Surveillance Requirement are clear. Neither the l

acceptance criteria nor the Surveillance Frequency of any Surveillance is reduced. I Furthermore, the four possible RPV configurations are all adequately monitored. As a result, the margin of safety for the low pressure conditions is not significantly reduced due to the proposed changes. l The Unit 1 operating curves were extended to 32 EFPY using approved methodologies. More operational margin is provided, because the three vessel regions (upper vessel and flange, beltline, and bottom head) are being separated for the inservice leak and hydrostatic testing curve, and the heatup and cooldown curve.

Although this separation results in more operating margin for certain vessel regions, it does not represent a significant reduction in the margin of safety. As described previously, the current Technical Specifications curves represent a composite of the three regions. Thus, the curves represent the temperature for the limiting region at a particular point. The regions that are not limiting at a particular point are artificially restricted. Separating the three regions, as proposed, eliminates false limits. The tme limit for each region is preserved and uncompromised, based on the use of approved methodologies.

In summary, this proposed amendment does not represent a signiticant reduction in the margin of safety because no actual limits are being relaxed, the four vessel configurations continue to be adequately monitored, all Surveillances continue to be performed within the same Frequencies, and the operating limits were developed using approved methods.

HL-5211 E2-3

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