ML20247N409
| ML20247N409 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 07/28/1989 |
| From: | GEORGIA POWER CO. |
| To: | |
| Shared Package | |
| ML20247N405 | List: |
| References | |
| NUDOCS 8908020392 | |
| Download: ML20247N409 (15) | |
Text
{{#Wiki_filter:- 1 CONTAINMENT SYSTEMS CONTAINMENT STRUCTURAL INTEGRITY LIMITING CONDITION FOR OPERATION 3.6.1.6 The structural integrity of the containment shall be maintained at a level consistent with the acceptance criteria in Specification 4.6.1.6. APPLICABILITY: Modes 1, 2, 3, and 4. ACTION: a. With the abnormal degradation indicated by the conditions in Specification 4.6.1.6.la.4, restore the containment to the required level of integrity or verify that containment integrity is maintained within 72 hours and perform an engineering evaluation of the containmenkand provide a Special Report to the Commission within 15 days in accordance with Specification 6.9.2 or be in at least HOT STANDBY within the next 6 hours and in COLD SHUTDOWN within the I to11owing 30 hours. b. With the indicated abnormal degradation of the structural integrity other than ACTION a. at a level below the acceptance criteria of Specification 4.6.1.6, restore the containment to the required level of integrity or verify that containment integrity is maintained within 15 days; perform an engineering evaluation of the containment and provide a Special Report to the Commission within 30 days in accordance with Specification 6.9.2 or be in at least HOT STANDBY within the next 6 hours and in COLD SHUTDOWN within the following 30 hours. The provisions of Specification 3.0.4 are not applicable. SURVEILLANCE REQUIREMENTS 4.6.1.6. CONTAINMENT PRESTRESSING SYSTEM The structural integrity of the prestressing tendons of the containment shall be demonstrated at the end of 1, 3, and 5 years following the initial containment vessel structural integrity test and at 5-year intervals thereafter. For combined inspections of two containment in a plant, the inspection schedule i t: ;; shown in N F9 we M -1 4.0.1.0.1 The adcovacy of prestressing forces in tendons shall be demonstrated by: {jN-cff fe.s}iy coiH be performed in accorduce w/M 8908020392 890728 ADOCK0500g4 PDR \\fDGTLE 0^)IT5-i f2 MV6C: O1 89 *s E eo . m m ~. _n __ n _ ____ _
m I and -- ^" ~ ple of at least a. Determining that a random'bu representative sam h inverted 13 tendons ( 9 hoo U)eachhaveanobserved11t-offforcewithTnthepredic d limits l-established for each tendon. For each subsequent inspection, one L tendon from each group shall be kept unchanged to develop a history i and to correlate the observed data. The procedure of inspection and the tendon acceptance criteria shall be as follows: 1. If the measured prestressing force of the selected tendon in a group lies above the. prescribed lower limit, the lift-off test is considered to be a positive indication of the sample tendon's acceptability. 2. If the measured prestressing force of the selected tendon in a group lies between the prescribed lower limit and 90% of the prescribed lower limit, two tendons, one on each side of this tendon shall be checked for their prestressine forces. It the prestressing forces of these two tendons are above 955 of the prescribed lower limits for the tendons, all three tendons shall be restored to the required level of integrity, and the tendon group shall be considered as acceptable. It the measured prestressing force of any two tendons falls below 951 of the prescribed lower limits of the tendons, additional lift-off testing sna11 be done to detect the cause and extent of such occurrence. The conditions shall be considered as an indication of abnormal degradation of the containment structures. INSERT] 3. It' the measured prestressing force of any tendon lies below 905 of the prescribed lower limit,.h efc:the t:;6; ehl' h
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...a The condition shall be considered as an indication of abnormal degradation of the containment structure. 4. If the average of all measured prestressing forces for each group (corrected for average condition) is found to be less than the minimum required prestress level at anchorage location for that group, the condition shall be considered as abnormal degradation of the containment structure. 5. If from consecutive surveillance the measured prestressing forces for the same tendon or tendens in a group indicate a trend of prestress loss larger than expected and the resulting prestressing forces will be less than the minimum required for the group before the next scheduled surveillairce, additional lift-off testing shall be done so as to detemine the cause and extent of such occurrence. The condition shall be considered as an indication of abnormal degradation at the containment structure. VOGTLE. OMITS - 2 Y 2
l 6. Unless there is abnormel degradation of the containment vessel during the first three inspections, the sample u k uon for subsequent inspections shall include at least tendons ( 4 hoop, orkl- .;.: D :. demay_.3 invert forOfff uly b. rPerforming tenti,on detensioning, inspections, and material tests on a previously stressed tendon from each group. A randomly selected tendon from each group stall be completely detensioned in ordar tn it!*ntify broken or damaged wires and determining that over the entire length of the removed wire sample (which. shou 1d include the broken wire if so i identified) that: 1. The tendon wires are free of corrosion, cracks, and damage, and 2. A minimum tensile strength of 2/0,000 psi (guaranteed ultimate strength of the tendon material) exists for at least three wire 9 mples (one from each end and one at mid-length) cut from each removed wire. Failure to meet the requirements of 4.6.1.6. shall be considered as an indication of abnormal degradation of the con 1;ainment structure. INSERT 2 Te.fera b; tenden reten;isa h; :f th;n 0:nd j: det;;; t s: f;r ^ C. in;; nt un t: :t k nt f:r = ke:1 r: ntd:d b..ur :: d:te: tr.t; Or th: pr:di;t:d ::h:, M:h:=r 4 ;r=ter. ritdh: tc h r e ce withi : S n 2:=:d 70" t th: ;=r=tnd nr:t:ph::bpr:= tit!l,htntt:f0uringretensioningofthese "---th :f th: tnd=: tendons, the changes in load and elongation should ha manured simultaneously at a minimum of three approximately equally spaced levels of force between zero and the seating force. If the elongation corresponding to a specific load differs by more than los from that recorded during the installation, en investigation should be made to ensure that the difference is not related to wire failures or slip of wires in anchorages. This condition shall be considered as en indication of abnormal degradation of the containment structure, d. Verifying the OPERABILITY of the sheathino filler grease by assuring: doe.riet 1. Therearenotchangesin a presence or physical appearance of the sheathing filler-grease i cluding the presence of free water. Amount ed grease replace exceed 5% of the net duct volume, when injected at :10" ef th: ;;nif u}. #:t:1hthn prunr:.e /NSENT.3 2. 3. Minimum grease coverage exists for the different parts of the anchorage system. 4.. During general visual examination of the containment exterior surface,es' grease leakage that could affect containment integrity is ruf present., and Vo& TLL t)A)1T5-1/2.
5. The chemical properties ot' the filler material are within the tolerance limits specified as follows: Water Content 0-10% (by dry wt.) Chlorides 0 - 10 ppm Nitrates 0 - 10 ppm Sulfides 0 - 10 ppm Reserved Alkalinity > 50% of the installed value; (BaseNumbers) 70 ' 'f:r N : ;r::: d . Failure to meet requirement of 4.6.1.6.1 shall be considered as an indication of abnormal degradation of the containment structure. /NSEAT// 4.6.1.6.2 End Anchorages and Adjacent "::: :t: Surfaces. A: ::.::: r:::: Of ___._u_..__.. .__m .m. t,^ rdc,, r: ':::5 :: S :r' L;;hte:, :tr:::bb ::h:r:,.::d;;;, : d i tt: h::d:) i._2___ 6. 2,m. __,__; _..,s,.,..............,,.-..........
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.,.....,,.....,.,.......'.__. _,h:d b::rin :::;;;:.t: .__2._. ,______2 -...-._.,J,r..... ... -. ____-.,, L_ 2.2__ A,.. 9L, ___A_ 2_A_ 05:;1d,h: b; :h::hed ei:r"y fer 'edM:t'en of ay :ter! r:d't'-. S Significa grease leatage, grease cap deformation or abnormal concrete /5/ee/g/a/;no condition shall be considered as an indication of abnormal degradation of J containment structure. 4.6.1.6.3 Containant 9seco3. Surfaces The exterior surface of the containment.should be visually examined to detect areas of large spall, severe scaling 0-cracking ' : := f O' :. ft. :: :; :, other surface deterioration or disintegration, o grease leakage, each of which can be <_ ___, tion of st,ructural i.ntegrity of the considered as, evidence of a,bnormal egrada __2 conta4 ,u. 7........ 7......... g 7 i, ep ..b s.i s. 7...... -see464ement -h;'.;;; -.;; ::::. signiAcan/ VOCvTLtl lJ^ HTS.i f 2 @@e . mtma u n_st_rm___n.
, ;s " ? INSERT 1 an engineering investigation will be performed to determ ne the cause and extent of the occurrence. INSERT 2 ~ For-Unit 1 only, performing tendon ret' ensioning of detensioned tendons as close as possible to their, observed or predicted lift-off force, - whichever is greater but' not to exceed a stress level of 70% of the guaranteed ultimate tensile strength (GUTS) for the tendon material. INSERT 3 a pressure.not to exceed the designers specifications. i INSERT 4 - The structural integrity of the end anchorages of all tendons inspected pursuant to Specification 4.6.1.6.1 and the adjacent surfaces shall be-demonstrated by determining through visual inspection that no apparent I changes have occurred. a. All end anchorages including anchor blocks, wedges, shims and . bearing plates: inspect for moisture, corrosion and cracks and for warping of bearing plates. b. Concrete surfaces adjacent to hoop tendon anchorages: inspect for moisture, corrosion, distortion and cracking. c. Steel plating surrounding the inverted-U tendon anchorages: inspect for moisture, corrosion, distortion and cracking. )
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l-INSERT 5 The tendon system for Unit 2 does not provide' for detensioning. l Detensioning can be performed only on the Unit 1 tendon system. l INSERT 6 The 1 year inspection for Unit 2 will consist of a visual. inspection only. No lift-off testing will be performed on Unit 2 until the 3 year inspection.
i CONTAINMENT SYSTEMS BASES j 3/4.6.1.5 AIR TEMPERATURE The limitations on containment average air temperature ensure that the ) overall containment average air temperature does not exceed the initial F temperature condition assumed in the safety analysis for a steam line break accident. Measurements shall be made at all listed locations, whether by fixed or portable instruments, prior to determining the average air temperature. 3/4.6.1.6 CONTAINMENT STRUCTURAL INTEGRITY This limitation ensores that the structural integrity of the containment will be maintained comparable to the original design standards for the life of the facility. Structural integrity is required to ensure that the containment will withstand the maximum pressure of 41.9 psig in the event of a steam line break accident. The measurement of containment tendon lif t-of f force, the ten-sile tests of the tendon strands for Unit 1, the visual examination of tendons, anchorages and exposed interior and exterior surfaces of the containment and the Type A leakage test for both units are sufficient to demonstrate this capa-bility. (The tendon strand samples will also be subjected to stress cycling tests and to accelerated corrosion tests to simulate the tendon's operating conditionsandenvironment.)gUnitIandUnit2 containments 5etisfytherecem- -mdaticar of o_egehtery Gu -Unit 2 containment;ubj-{ttov;5cciin5pecticaonlyr e 1.35, Deuirien 2, Peitier C.1v3. %ereferer Y INSERT 7 The Surveillance Requirement 5 for demcarrttating the 5tructural-etegf+ty-Q c6 cf each containment 15 in compliance.iith the recemmend5tiens of Rev;;ien 2 of widi 9" 0 Y I' i 6 II#'"
- i 3
p f8 Stressed Ccncrete ;cnt3inment Structures," end picpesed Regulate., Ca ce 1. Z.1, A " Determining Prestre55ing Terce; f;r M pecti;r ;; Sc;trc;;;d C:r.cr:t: Cc" toinment5," April 1 2. The required Special Reports from any engineering evaluation of contain-ment abnormalities shall include a description of the tendon condition, the condition of the concrete (especially at tendon anchorages), the inspection procedures, the tolerances on cracking, the results of the engineering evalua-tion, and the corrective actions taken orprogsec/ j 3/4.6.1.7 CONTAINMENT VENTILATION SYSTEM The 24-inch containment purge supply and exhaust isolstion valves are required to be sealed closed during plant operations since these valves have not been demonstrated capable of closing during a LOCA or steam line break accident. h Maintaining these valves sealed closed during plant operation ensures that exces-7 sive quantities of radioactive materials will not be released via the Containment Purge System. To provide assurance that these containment valves cannot be inad-vertently opened, the valves are sealed closed in accordence with Standard Review Plan 6.2.4. Sealed closed isolation valves are isolation valves under admini-strative control to assure that they cannot be inadvertently opened. Admini-g strative control includes mechanical devices to seal or lock the valve closed. the use of blind flanges, or removal of power to the valve operator. V0GTLE UNITS - 1 & 2 B 3/4 6-2 L
INSERT 7 With regard to D-cracking, the acceptance criteria for the visual inspection of the containment concrete is that the area comprising D-cracking should not exceed 25 sq.ft. INSERT 8 The conditions referenced by Action statement 3.6.1.6.b do not define abnormal containment degradation. These conditions are indications of potential abnormal degradation and their existence requires an . appropriate engineering evaluation and a Special Report in accordance with Specification 6.9.2. J i l 1558n I I
M A CONTAINMENT SYSTEMS CONTAINMENT STRUCTURAL INTEGRITY LIMITING CONDITION FOR OPERATION 3 6.1.6 The structural integrity of the containment shall be maintained at a l level consistent with the acceptance criteria in Specification 4.6.1.6. APPLICABILITY: Modes 1, 2,- 3, and 4. ACTION: a. With the abnormal degradation indicated by the conditions in Specification 4.6.1.6.la.4, restore the containment to the required level of. integrity or verify that containment integrity is maintained within 72 hours and perform an engineering evaluation of the containment and provide a Special Report to the Commission within 15 days in accordance with Specification 6.9.2 or be in at least HOT STANDBY within the next 6 hours and in COLD SHUfDOWN within the following 30 hours, b. WitF the indicated abnormal degradation of the structural integrity other than ACTION a. at a level below the acceptance criteria of Specification 4.6.1 6, restore the containment to the required level of integrity or verify that containment integrity is maintained -within 15 days; perform an engineering evaluation of the containment and provide a Special Report to the Commission within 30 days in accordance with Specification 6.9.2 or be in at least HOT STANDSY within the next 6 hours and in COLD SHUTDOWN within the following 20 hours. The provisions of Specification 3.0.4 are not applicable. SURVEILLANCE REQUIREMENTS 4.6.1.6 CONTAINMENT P,PESTRESSING SYSTEM The structural integrity of the prestressing tendons of the containment shall be demonstrated at the end of 1, 3, and 5 years following the initial containment vessel structural integrity test and at 5-year intervals thereafter. For combined inspections of two containments in a plant, lift-off H testing will be performed in accordance with the inspection schedule shown in Figure 3.6-1. . 4. 6.1. 6.1 The adequacy of prestressing forces in tendons shall be demonstrated by: L a. Determinit#g that a random but representative sample of at least 13 tendons (9 hoop and 4 inverted-U) each have an observed lift-off V0GTLE UNITS - 1 & 2 3/4 6-8
CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) force within the predicted limits established for each tendon. For each subsequent inspection, one tendon from each group shall be kept unchanged to develop a history and to correlate the observed data. The procedure of inspection and the tendon acceptance criteria shall be as follows: 1) If the measured prestressing force of the selected tendon in a group lies above the prescribed lower limit, the lift-of f test is considered to be a positive indication of the sample tendon's acceptability. 2) If the measured prestressing force of the selected tendon in a group lies between the prescribed lower limit and 90% of the prescribed lower limit, two tendons, one on each side of this tendon, shall be checked for their prestressing forces. If the prestressing forces of these two tendons are above 95% of the prescribed lower limits for the tendons, all three tendons shall be restored to the required level of integrity, and the tendon group shall be considered as acceptable. If the measured prestressing force of any two tendons falls below 95% of the prescribed lower limits of the tendons, additional lift-off testing shall be done to detect the cause and extent of such occurrence. The conditions shall be considered as an indication of abnormal degradation of the containment structure. 3) If the measured prestressing force of any tendon lies below 90% of the prescribed lower limit, an engineering investigation will be performed to determine the cause and extent of the occurrence. The condition shall be considered as an indication of abnormal degradation of the containment structure. 4) If the average of all measured prestressing forces for each 9.oup (corrected for average condition) is found to be less than the minimum required prestress level at anchorage location for that group, the condition shall be considered as abnormal degradation of the containment structure. 5) If from consecutive surveillences the measured prestressing forces for the same tendon or tendons in a group indicate a trend of prestress loss larger than expected and the resulting prestressing forces will be less than the minimum required for the group before the next scheduled surveillance, additional lift-off testing shall be done so as to determine the cause and extent of such occurrence. The condition shall be considered as an indication of abnormal degradation of the containment structure.
- 6) Unless there is abnormal degradation of the containment vessel during the first three inspections, the sample population for subsequent inspections shall include at least 7 tendons (4 hoop, and 3 inverted-U).
b. For Unit 1 only, performing tendon detensioning, inspections, and material tests on a previously stressed tendon f rom each group. V0GTLE UNITS - 1 & 2 3/4 6-9
CONTAINMENT SYSTEMS q j.. SURVEILLANCE REQUIREMENTS (Continued) m b A randomly selected tendon from each group shall be completely detensioned in order to identify broken or damaged wires and h determining that over the entire length of the removed wire sample (which should include the broken wire if so identified) that:
- 1) The tendon wires are free of corrosion, cracks, and damage, and
- 2) A minimum tensile strength of 270,000 psi (guaranteed ultimate-strength of the tendon material) exists for at least three wire samples-(one from each end and one at mid-length) cut from each removed wire.
Failure to meet the requirements of 4.6.,1.6.lb shall be considered as an indication of abnormal degradation of the ~ containment structure. c. For Unit 1 only, performing tendon retensioning of detensioned tendons as close as possible to their observed or predicted lift-off force, whichever is greater but not to exceed a stress level of 70% of the guaranteed ultimate tensile strength (GUTS) for the tendon material. During retensioning of these tendons, the changes in load and elongation should be measured simultaneously at a minimum of three approximately equally-spaced levels of force between zero and the seating force. If the elongation corresponding to a specific load differs by more than 10% from that recorded during the installation, an investigation should be made to ensure that the difference is not related to wire f ailures or slip of wires in anchorages. This condition shall be considered as an indication of abnormal degradation of the containment structure. d. Verifying the OPERABILITY of the sheathing filler grease by assuring:
- 1) There are no changes in the presence or physical appearance of the sheathing. filler-grease including the presence of free water.
- 2) Amount of grease replaced does not exceed 5% of the net duct volume, when injected at a pressure not to exceed the designer's specifications.
- 3) Minimum grease coverage exists for the different parts of the anchorage system.
- 4) During general visual examination of the containment exterior surface, grease leakage that could affect containment integrity
.is not present, and
- 5) The chemical properties of the filler material are within the tole snce limits specified as follows:
V0GTLE UNITS - 1 & 2 3/4 6-9a
CONTAINMENT' SYSTEftS 14 SURVEltLANCE REQUIREMENTS (Continued) l . Water Content 0-10% (by dry wt.) 1 Chlorides 0-10 ppm l Nitrates 0-10 ppm Sulfides 0-10 ppm Reserved Alkalinity >50% of the installed value; -(Base Numbers) Failure to meet requirement of 4.6.1.6.1d shall be considered as an indication of abnormal degradation of the containment structure. '4.6.1.6.2. End Anchorages and Adjacent Surf aces. The structural integrity of the end anchorages of all tendons inspected pursuant to Specification 4.6.1.6.1 and the adjacent surfaces shall be demonstrated by determining-l through visual inspection that no apparent changes have occurred. l All end anchorages including anchor blocks, wedges, shims, and a. bearing plates: inspect for moisture, corrosion and cracks, and for warping of bearing plates. b. Concrete surfaces adjacent to hoop tendon anchorages: inspect for moisture,'corresion, distortion, and cracking. Steel plating surrounding the inverted-U tendon anchorages: inspect c. for moisture, corrosion, distortion, and cracking. Significant grease leakage. grease cap deformation, or abnormal concrete / steel plating conditions shall be considered as an indication of abnormal degradation of containment structure. 4.6.1.6.3 Containment Surfaces. The exterior surface of the containment should be visually examined to detect areas of large spall, severe scaling, D-cracking, other surface deterioration or disintegration, or significant grease leakage, each of which can be considered as evidence of abnormal degradation of structural integrity of the containment. ~ I I t
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l y 2__ .._ n.:._. - _;_ SAMPLE SIZE CRITERIA (SEE SECTION 4.6.1.6.1) 4 %). 4 4%! 2%i j1 3 1,5 2,5 3,5 TIME AFTER INITIAL STRUCTURAL INTEGRITY TESTING OF CONTAINMENT, YEARS (Lift-off Testing Schedule, Containment No.1) i. 9 3 5 1,5 2,5: 3,5 TIME AFTER INITIAL STRUCTURAL INTEGRITY TESTING OF CONTAINMENT, YEARS (Lift-off Testing Schedule, Containment No. 2) - Schedule to be used provided: 'a. The containments are identical in all aspects such as size, tendon system, design, materials of construction, and method of construction. The tendon system for Unit 2 does not provide for detensioning. Detensioning can be performed only on the Unit 1 tendon system, b.. The 1 year inspection for Unit 2 will consist of a visual inspection only. No lift-off testing will be performed on Unit 2 until the 3 year inspection.
- c. There is no unique situation that may subject either containment to a
a different potential for structural or tendon deterioration. FIGURE 3.6-1 SCHEDULE OF LIFT-0FF TESTING FOR TWO CONTAINMENTS AT A SITE V0GTLE UNITS-1 & 2 3/4 6-10
CONTAINMENT SYSTEMS l BASES l M4.6.1.5 AIR TEMPERATURE The limitations on containment average air temperature ensure that the overall containment average air temperature does not exceed the initial temperature condition assumed in the safety analysis for a steam line break accident. Measurements shall be made at all listed locations, whether by fixed or portable instruments, prior to determining the average air temperature. 3/4.6.1.6 CONTAINMENT STRUCTURAL INTEGRITY This linncation ensures that the structural integrity of the containment will be maintained comparable to the original design standards for the life of the facility. Structural integrity is required to ensure that the containment will withstand the maximum pressure of 41.9 psig in the event of a steam line break accident. The measurement of containment tendon lift-off force, the ten-sile tests of thc tendon strands for Unit 1, the visual examination of tendons, anchorages and exposed interior and exterior surfaces of the containment and the Type A leakage test for both units are sufficient to demonstrate this capa-bility. (The tendon strand samples will also be subjected to stress cycling tests and to accelerated corrosion tests to simulate the tendon's operating conditions and environment.) With regard to D-cracking, the acceptance criteria for the visual inspection of the containment concrete is that the area comprising D-cracking should not exceed 25 sq. f t. The conditions referenced by Action statement 3.6.1.6.b do not define abnormal containment degradation. These conditions are indications of potential abnormal degradation and their existence requires an appropriate engineering evaluation and a Special Report in accordance with Specification 6.9.2. The required Special Reports f rom any engineering evaluation of contain-ment abnormalities shall include a description of the tendon condition, the condition of the concrete (especially at tendon anchorages), the inspection procedures, the tolerances on cracking, the results of the engineering evalua-tion, and the corrective actions taken, or proposed. l 3/4.6.1.7 CONTAINMENT VENTILATION SYSTEM The 24-inch containment purge supply and exhaust isolation valves are required to be sealed closed during plant operations since these valves have not been demonstrated capable of closing during a LOCA or steam line break accident. Maintaining these valves sealed closed during plant operation ensures that exces-sive quantities of radioactive materials will not be released via the Containment Purge System. To provide assurance that these containment valves cannot be inad-vertently opened, the valves are sealed closed in accordance with Standard Review Plan 6.2.4. Sealed closed isolation valves are isolation valves under admini-strative control to assure that they cannot be inadvertently opened. Admini-strative control includes mechanical devices to seal or lock the valve closed, the use of blind flanges, or removal of power to the valve operator. V0GTLE UNITS - 1 & 2 B 3/4 6-2 _ - _ _ - _ _ - _ _ - - _ _.}}