ML20077E805

Proposed Tech Specs Changes 3/4.6.5.1,one Time Increase in Surveillance Interval for Ice Weighing

ML20077E805
Person / Time
Site:	Mcguire
Issue date:	06/05/1991
From:	DUKE POWER CO.
To:
Shared Package
ML20077E792	List: ML20077E789 ML20077E805
References
NUDOCS 9106110234
Download: ML20077E805 (25)

Text

_ _ _ _ _ _ _____-_

ATTACllMENT 1 CONTAINHENT SYSTEMS 3/4.6.5 ICE CONDENSER ICE RED LIMITING CON 0! TION FOR OPERATION 3.6.5.1 The ice bed shall be OPERABLE with:

a. The stored ice having a boron concentration of at least 1800 ppm boron as sodium tetraborate and a pH of 9.0 tc 9.5,

b. Flow channels through the ice condenser,

c. A maximum ice bed temperature of less than or equal to 27'F,

d. A total ice weight of at least 2,466,420 pounds at a 95% level of confidence, and

e. 1944 ice baskets.

APPLICABILITY: H00E5 1, 2, 3, and 4 ACTION:

With the ice bed inoperable, restore the ice bed to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUT-DOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS 4.6.5.1 The ice condenser shall be determined OPERABLE:

a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by using the Ice Bed Temperature o Monitoring System to verify that the maximum ice bed temperature is t.,p, $ less than or equal to 27'F, CO'1

$8 b. At least once per 9 months by:

YS.

, 1) Chemical analyses which verily that at least nine representative c43 samples of stored ice have a boron concentration of at least

@l8 1800 ppm as sodium tetraborate and a pH of 9.0 to 9.5 at 20*C;

-a 5 e 2) Weighing a representative sample of at least 144 ice baskets 3s and verifying that each basket contains at least 1269 lbs of oLa ice. The representative sample shall include 6 baskets from each of the 24 ice condenser bays and shall be constituted of f re.c U ;+ 2 s ely , th;s Sur vslIlone is ad eqwerd h be f r !c e # rol<J;/ He ,r e d eday ce su M ,e.,,t Ara +L , but no la +e r t%

2. l a r /9 2.

McGUIRE - UNITS 1 and 2 3/4 6-34

-Aal clos 9es 7 /s . 3 kt" CONTAINMENT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

I basket each from Radial Rows 1, 2, 4, 6, 8, and 9 (or from the same row of an adjacent bay if a basket from a designated row cannot be obtained for weighing) within each bay. If any basket is found to contain less than 1269 pounds of ice, a representative sample of 20 additional baskets from the same bay shall be weighed. The minimum average weight of ice from the 20 additional baskets and the discrepant basket shall not

• be less than 1269 pounds / basket at a 95% level of confidence.

The ice condenser shall also be subdivided into 3 groups of baskets, as follows: Group 1 - Bays 1 through 8 Group 2 -

Bays 9 through 16, and Group 3 - Bays 17 through 24. The minimum average ice weight of the sample baskets from Radial Rows 1, 2, 4, 6, 8, and 9 in each group shall not be less than 1269 pounds / basket at a 95% level of confidence.

The minimum total ice condenser ice weight at a 95% level of confidence shall be calcul.ated using all ice basket weights determined during this weighing program and shall not be less than 2,466,420 pounds; and

3) Verifying, by a visual inspection of at least two flow passages per ice condenser bay, that the accumulation of frost or ice on flow passages between ice baskets, past lattice frames, through the intermediate and top deck floor grating, or past the lower inlet plenum support structures and turning vanes is restricted to a thickness of less than or equal to 0.38 inch. If one flow passage per bay is found to have an accumulation of frost or ice with a thickness of greater than or equal to 0.38 inch, a representative sample of 20 additional flow passages from the same bay shall be visually inspected. If these additional flow passages are found acceptable, the surveillance program may proceed considering the single deficiency as unique and accept-able. More than one restricted flow passage per bay is evidence of abnormal degradation of the ice condenser,

c. At least once per 40 months by lifting and visually inspecting the accessible portions of at least two ice baskets from each one-third cf the ice condenser and verifying that the ice baskets are free of detrimental structural wear, cracks, corrosion, or other damage.

The ice baskets shall be raised at least 12 feet for this inspection.

McGUI M - UMTS 1 and 2 3/4 6-35 ______________ _

- A)c Citages This fa3 e CONTAINMENT SYSTEMS BASES 3/4.6.5 ICE CONDENSER The requirements associated with each of the components of the ice con-denser ensure that the overall system will be available to provide sufficient pressure suppression capability to limit the containment peak pressure tran-sient to less than 14.8 psig during LOCA conditions.

3/4.6.5.1 ICE BE0 will:

The OPERABILITY of the ice bed ensures that the required ice inventory (1) be distributed evenly through the containment bays, (2) contain sufficient boron to preclude dilution of the containment sump following the LOCA, and (3) contain sufficient heat removal capability to condense the Reactor Coolant System volume released during a LOCA. These conditions are consistent with the assumptions used in the accident analyses.

The minimum weight figure of 1269 pounds of ice per basket contains a 10%

conservative allowance for ice loss through sublimation which is a factor of 10 higher than assumed for the ice condenser design. The minimum weight figure of 2,466,420 pounds of ice also contains an additional 1% conservative allowance to account for systematic error in weighing instruments. In the event that observed sublimation rates are equal to or lower than design predictions after 3 years of operation, the minimum ice baskets weight may be adjusted downward.

In addition, the number of ice baskets required to be weighed each 9 months may be reduced after 3 years of operation if such a reduction is supported by observed sublimation data.

3/4.6.5.2 ICE BED TEMPERATURE MONITORING SYSTEM The OPERABILITY of the Ice Bed Temperature Monitoring System ensures that the capability is available for monitoring the ice temperature. In the event the system is inoperable, the ACTION requirements provide assurance that the ice bed heat removal capacity will be retained within the specified time limits.

3/4.6.5.3 ICE CONDENSER DOORS The OPERABILITY of the ice condenser doors and the requirement that they be maintained closed ensures that the Reactor Coolant System fluid released l

during a LOCA will be diverted through the ice condenser bays for heat removal and that excessive sublimation of the ice bed will not occur because of warm air intrusion.

l If an ice condenser door is not capable of opening automatically, then I system function is seriously degraded and immediate action must be taken to restore the opening capability of the door. Not capable of opening automati-cally is defined as those conditions in which a door is physically blocked from opening by installation of a blocking device or by obstruction from temporary or permanent installed equipment or is otherwise inhibited from opening such as may result from ice, frost, debris or increased door opening torque.

Amendment No. 26 (Unit 2)

McGUIRE - UNITS 1 and 2 8 3/4 6-5 Amendment No. 45 (Unit 1)

%fX489

A'ITACHMENT 2 ONE TIME INCREASE IN SURVEILLANCE INTERVAL OF TS - 4.6.5.1 ICE CONDENSER BASKET WEIGHT DETERMINATION 1

I. BACKGROUND l The primary function of the Ice Condenser System is the absorption of thermal energy released abruptly in the event of a Loss Of Coolant Accident (LOCA) for the purpose of limiting the initial peak pressure in Containment.

The Ice Condenser is subdivided into 24 bays which contain a total of 1944 ice baskets that i are 12 inches in diameter and 48 feet long. Each bay consists of 9 columns and 9 rows of ice baskets. The ice basket assembly columns are composed of 4 basket sections approximately 12 feet long each, filled with borated ice. The ice bed function is to promote heat transfer from the steam to the ice during and following a LOCA or steam line break in the Containment by ensuring the ice inventory is evenly distributed, contains sufficient heat removal capability, and is maintained in the appropriate geometry. The Ice Condenser is also administratively subdivided into 3 groups of baskets for the purpose of ice weighing.

Group I consists of bays 1 through 8, Group 2 consists of bays 9 through 16, and Group 3 consists of bays 17 through 24 The baskets are formed from a 14 gage (0.075 inches) perforated sheet metal. The perforated basket assembly has an open area of approximately 64 percent to provide the necessary surface area for heat transfer between the steam / air mixture and the ice to limit the Containment pressure within design limits. Interconnection couplings and stiffening rings are located at the bottom and at 6 foot levels of each basket section respectively. The coupling and stiffening rings are cylindrical in shape and approximately 3 inches high with a rolled internal lip. The lip provides stiffening to the basket.

Two U-bolts, located at the bottom of each ice basket column, affix the basket by means of a clevis assembly to its lower support structure. This assembly serves to provide assurance that the ice basket does not lift-off under the loading condition represented by a Design Basis Accident (DBA). The U-bolts are Cadmium plated,3/8 inch in diameter, SAE J 429 Grade 8 material.

Licensee Event Report (LER) 369/90-28 was submitted after it was determined that a potential failure mode existed in the ice basket U-bolts currently installed in the Unit I and 2 Ice Condensers. The operability evaluation developed at that time concluded that present ice weighing methods may compromise the integrity of the existing U-bolt assemblics, therefore, making it impractical to weigh ice while the unit is on line or in Modes 1 through 4.

Technical Specification (TS) 3/4.6.5.1 specifies that the ice bed shall be operable with a total ice weight of at least 2,099,790- pounds at a 95% level of confidence with 1944

baskets. This is the minimum amount of ice to be maintained in the Ice Condenser to control the anticipated heat load during a large scale LOCA. These conditions are applicable in Modes 1 through 4. The TS Action statement specifies that with the ice bed inoperable, restore the ice bed to opera' ole status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or the unit must be in at least Hot Standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in Cold Shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

The current peak containment pressure transient safety analysis assumes 1,890,000* pounds of ice initially in the Ice Condenser. A 10% conservatise allowance for ice bed loss through sublimation is added to the above value as well as a 1.1 % allowance to account for errors in the weighing instruments. These consenative allowances are intended to ensure that the actual total ice weight remains above the value assumed in the FSAR analysis for the duration of the fuel cycle. Thus, the TS minimum ice bed weight is calculated as 1,890,000* lbs, plus 11.1 % (209,790* lbs.) for a tetal weight of 2,099,790* lbs. This value when civided by the number of ice baskets (1944) determines the minimum average TS ice weight per basket as 1081* pounds.

TS Sun'elllance requirement 4.6.5.1 b(2) currently requires that at least once per 9 months a representative sample of at least 144 ice baskets be weighed to verify with a 95% level of Confidence (LOC) that the minimum average weight for Bay and Row Group ice baskers is at least 1081* lbs. with a minimum total ice bed weight of 2,099,790* lbs. If any basket is found to contain less than 1081* lbs. of ice, a representative sample of 20 additional baskets from the same Bay shall be weighed. The minimum average weight of ice from the 20 additional baskets and the discrepant basket shall not be less than 1081* lbs per basket at a 95 % LOC. The basis for this requirement recognizes that rublimation will occur during Unit operation resulting in lowered ice weights (some possibly below 1081* lbs.), md it is not meant to impose this weight limit for all baskets at all times as long as the total ice weight can be shown not to be less than 2,099,790* lbs. at the surveillance period.

As noted above, the TS Limiting Condition for Operation total ice weight (2,099,790* lbs.)

is to ensure the actual ice bed weight remains above the value assumed in the FSAR analysis for the duration of the fuel cycle (1,890,000* lbs.). Therefore, the TS surveillance requirements were written to ensure that the actual minimum average ice weight for any statistical sub-group always remains above 973 Ibs, per basket (1,890,000* lbs. divided by 1944 baskets). The 973* lbs. per basket required by the safety analysis plus a 1.1%

weighing uncertainty factor equals 983* lbs. per basket and is referred to as the safety margin weight for each ice basket. As long as the measured minimum average ice weight per basket remains above 983* lbs. from one refueling outage to the next, an adequate safety margin is maintained.

l .

II. TECHNICAL JUSTIFICATION In order to provide justi0 cation for a one time TS change to extend the surveillance interval for Unit 2 ice bask.et weighing from 9 months to the next refueling outage (~ 17 months),

past operating experience at hicGuire Unit 2 was analyzed to evaluate ice basket sublimation rates. The current TS total ice weight and minimum average ice basket ice weights are based upon a 10% per nine month sublimation rate as discussed in the

" Background" section of this attachment. The approach to justify the proposed amendment is based on a projection of current ice weight through the present Unit 2 fuel cycle.

Beginning of Cycle (BOC) ice weight data, worst case historical sublimation rates, and a multiplier,150%, for additional conservatism were used to project ice weight at the end of cycle 7 to be 116 lbs. above the TS ice weight limit of 1081* lbs. The current date for the Unit 2 refueling outage to begin is January 16, 1992. Attachment 2A shows that even if the outage is pushed back to February 27,1992, there is still 76 lbs, of ice above TS.

As shown in the table below, the worst case average sublimation rates for Unit 2 is located in Row 9, Group 3, and is used as the basis for the projections presented in the grapn in Attachment 2A, UNIT 2 hiAX HISTORICAL ROW GROUP SUBLlh1ATION RATES CYCLE 2 THROUGH CYCLE 6 BAS"D ON 95% LOC BEGINNING OF CYCLE TO END OF CYCLE DATA SUBLIM. RATE ROW OROUP CYfLE_ (LBSJMQ1L) 9 3 4 18.9 9 2 5 18.8 9 1 6 16.0 9 1 4 15.6 9 3 5 14.7 In addition, to demonstrate what safety margin exists, the worst case Row 9 average Group ice basket ice weight (Row 9, Group 2; 1554 lbs.) from the last weighing surveillance were projected to February 27, 1992. The Row 9 Group 2 average ica weight was projected using the actual Row 9 sublimation rates and also a multiplier of 150% for additional conservatism. These projected weights were compared to the safety margin weight of 983' lbs. per basket to ensure design basis minimum Ice Condenser weight was not challenged.

As stated in the Background section, the safety margin weight for each basket is calculated by dividing the total amount of ice assumed in the LOCA safety analysis (1,890,000* lbs.)

by the number of ice baskets (1944) and adding an additional amount of ice for measurement inaccuracies (1.1%). This analysis showed that the projected average ice weight of Row 9 Group 2 ice baskets remained approximately 18% over the over the safety 1

margin weight of 983* lbs. (-22% margin exists if refueling outage begins as scheduled).

III. CONCLUSIONS The conservative analytical approach towards projecting ice weight based on the worst case sublimation rates demonstrates that with a high level of con 6dence, adequate ice mass will exist in the Unit 2 Ice Condenser at the end of cycle 7. Projections indicate that the worst case mean ice weight will be 76 lbs. above TS limit * (116 lbs above TS limit

• if outage begins Ls currently scheduled). The request for the one time extension of the Unit 2 ice weighing surveillance interval is therefore technically justined.

• - Denotes the ice weight reduction Technical Speci6 cation Amendment previously submitted June 7,1990.

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MCGU1RE UNIT 2, CYCLE 7. ROW 9, GROUP 2 i WORST CASE ICE WEIGHT PROJECTIONS T

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ATTACHMENT 3 FROPOSED AMENDMENT TO TS 3/4.6.5.1 SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION Duke Power has evaluated the proposed TS change and has determined that it does not represent a significant hazards cont.ideration based upon the criteria established in 10CFR50.92(c). Operation of McGuire Nuclear Station in accordance with the proposed amendment will not:

(1) Involve a significant increase in the probability or consequences of an accident previously evaluated.

Duke proposes to modify the McGuire Nuclear Station Unit 2 Technical Specifications to revise Surveillance requirement 4.6.5.1 (b)(2) to allow a one time extension of the 9 month ice weighing interval to the following refueling outage. The Ice Condenser System serves as an accident mitigation system and an extension to confirm actual ice weight is not an accident initiator.

The Ice Condenser is provided to absorb the thermal energy release following a LOCA or steam line break inside Containment at d thereby limiting the peak Containment pressure.

The current design analysis is based upon a minimum average ice weight of 973* lbs. per basket (totalice bed weight of 1,890,000* lbs.). Calculations using historicalIce Condenser sublimation data with consevatism of 150%, indicate that the total ice bed weight will remain well above that value assumed in the safety analysis. Therefore, the consequences i af an accident previously analyzed is not increased.

(2) Create the possibility of a new or different kind of accident from any previously analyzed.

Duke Pov er's request for a one time extension of the Unit 2 ice weighing interval will not result in a new or different kind of accident from that previously analyzed in McGuire's Final Safety Analysis Report (FSAR). A one time extension of the surveillance interval for this accident mitigation system is not considered to be an accident initiator. The TS ice weights derived from the safety analysis weight plus additional allowances of 10% for sublimation and 1.1% for weighing errors will ensure that the ice bed will not decrease below the design bases weight over the proposed surveillance interval. Therefore, the peak Containment pressure assumed in the safety analysis is still valid. This amendment involves no equipment changes or how the Ice Condenser system is operated.

(3) Involve a significant reduction in the margin of safety.

The Ice Condenser is designed to limit the Containment pressure below the design pressure for all reactor coolant pipe break sizes up to and including a double-ended severance. With

Attachment 3 Page 2 a multiplier of 150% for additional conservatism, the worst case ice weight remains approximately 18% above the ice basket safety margin weight of 983 lbs. Because the minimum required ice weight assumed in the safety analysis is not being altered, the margin of safety as described in the Peak Containment Pressure Transient is not impacted.

The Ice Condenser also serves as a Containment air purification and cleanup system by absorbing molecular iodine from the containment atmosphere following a LOCA. The required boron concentration of the stored ice is not affected by this TS change request.

Therefore, the air purification aspects of the Ice Condenser remain unchanged by this submittal and the margin of safety is not adversely impacted.

Environmental Impact The proposed Technical Specification change has been reviewed against the criteria of 10CFR 51.22 for environmental considerations. As shown above, the proposed change does not involve a significant hazards consideration, nor increase individual or cumulative occupational radiation exposures. Based on this, the proposed TS change meets the criteria given in 10CFR 51.22(c)(9) for a categorical exclusion from the requirement for an environmental impact statement.

• -Denotes the ice weight reduction Technical Specification Amendment previously submitted June 7,1990.

ATTACilMENT 4 DUKE POWER lL, COMPANY MCGUIRE

/ NUCl. EAR STATION

)' UNIT 2 ICE CONDENSER I -. 1 -

_ TECH SPEC 3/4.6.5.1

. l AMENDMENT D NitC PilESENTATION OVEllVIEW l

MAY 22,1991 j' s l

ICE CONDENSER SYSTEM PURPOSE The Ice Condenser's primary function is to mitigate the containment pressure consequences associated with a Loss Of Coolant Accident or Main Steam Line Break inside containment.

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ICE CONDENSER TECHNICAL SPECIFICATION  !

LIMITING CONDITION OF OPERATION Minimum total ice weight at a 95% level of confidence - 2,099,790 lbs SURVEILLANCE REQUIREMENTS Survey 144 baskets, all must be greater than 1081 lbs/ basket ice If incur light basket, must survey 20 additional .

baskets in that bay - 95% loc mean basket ice weight must be greater than 1081 lbs Mean row group ice weight at a 95% loc must  :

be greater than 1081 lbs/ basket Mean total ice weight at a 95% loc must be greater than 2,099,790 lbs

4 ICE CONDENSER ICE WEIGHT REDUCTION TECH SPEC AMENDMENT PURPOSE To preclude mid-cycle ice replenishment outages during the forthcomming longer core cycles BASES l Reduced ice weight LODIC analysis defining postulated containment pressure / temperature transients within design limits PEAK CONTAINMENT PRESSURE EFFECT l ICE PEAK CONTAINMENT TECH SPEC WEIGHT PRESSURE LIMIT 2,2 2 0,0 0 0lbs 12.3 6 psig 14.8psig 1,8 9 0,0 0 0lbs 14.0 7 psig 14.8psig STATUS NRC approval espected within the next 2 weeks

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ICE CONDENSER U-BOLT ISSUE FAILURE MODE Manuf acturing flaw propagated by construction /

maintenance induced loading OPERABILITY EVALUATION Performed proof load test

- demonstraited U-Bolt integrity and low failure rate

- established U-Bolt's ability to withstand a design basis load during the following load cycle

- excluded future on-line ice weighing LONG TERM PLAN Replace U-Bolts with swivel mounting bracket during the next 4 refueling outages EFFECT ON ICE WEIGHING On-line weighing is excluded for both Units On-line weighing may be performed on baskets with swivel mounting bracket

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l ICE CONDENSER REQUESTED TECH SPEC AMENDMENT REQUEST Amend Tech Spec 3 /4.6.5.1 to extend the surveillance interval for Unit 2 Cycle 7 to the next refueling outage PURPOSE Preclude a mid-cycle outage for ice weight surveillance CONSEQUENSES IF NOT GBTAINED Implement less desirable options

- on-line weighing of non-ejectable baskets

- off-line ice weight surveillance I

e ICE CONDENSER l TECHNICAL JUSTIFICATION l

OVERVIEW i Justification based on a projection of current ice weight through the current fuel cycle l Projection incorporates

- BOC ice weight data at a 95% loc l 1

Worst case historical sublimation rates Cycle 2 through Cycle 6

- 150% subli. rate multiplier for unknowns Paiected ice weight at the end of cycle -

1161bs above TECH SPEC fce weight.

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m MCGUIRE NUCLEAR STATION UNIT 2 BAY SUBUMATION RATES

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• ', Ae_1/2-Row ,e12 y

now - - -

Y GROLP GROUP

ICE CONDENSER TECHNICAL JUSTIFICATION OVERVIEW WORST CASE SUBLIMATION RATES CYCLE 2 THROUGH CYCLE 6 SUBLIMATION RATE ROW OROUP CYCLE (los/ month) 9 3 4 18.9 9 2 5 18.8 9 1 6 16.0 9 1 4 15.6 9 3 5 14.7 ANALYSIS PROJECTION FORMULA Wt = W t>oe - [ SR

• Man * (De - Dboc) ]

I

\\l 1Il l!

=MZ~ 2 5>_ wCy b3:O

-J3 N ]:CZ ,f h ~<-

e 8 8 r

g 1 1 *v

~

e

= b W w W S e n e n .

S k k r e e o e Ww~w i

L C t C C O e O t. O k* E e E e E

,- M=M.M l' t

31 i ;

i' II! I hn

' hs I hn E n T 3 ha A p u

YR o r

r RL G~ a AB It v MU l4 h, DMS EUE BSS g1 _ ,

EN A hm COC I

I Sa 7T T v ELEC S R 2 p a CJO Y OW u

o r

ha G - hs CR P F - Es 2 T O $a T H%

I NG0 5 0' ' j 4

hs UlE1 P +

WN l

[' hs EO ,

CD I 1 hs E p S u o

s A r u

B G ha Pl $s

- jllj ,fj;1 Ijl .:+

0 0 0 0

6 a g a 0 6 a m 1 , t T

M )s NEKb E(

W t li! \l! l lll l '1l(l lll l

e a

UNIT 2. CYCLE 7. ROW 9. GROUP 2 g WORST CASE ICE WEIGHT PROJECTIONS E =

n.

~ 7, 1600 - O C

>~

1 j .15s4

,- @Z 1500 + i 9- WW Cas* SA C j

t 18 9 W M. y m

w-1800 e-- 15CE et W rst Cs=* SA 29 3 W My-m Om BASKET 3aco i K:E  !

~

• tm n.,c.a Te w ,

qq ~

WEGfT UN 12m +'

,.. ""i 1

$N

^-

E eliS7 > BOC 7 D*C 291730

• v v t

116 33 % i 75 tosi j

-~ ~ W M EOC7

'd Z y

l l Jan 16.1992 3

! Z to i  ;

983 l - %w '

l wmn.,m ,

r 1 l . +-

g p +- 4 -

h90 Jan-91 Mar-91 Aw-91 h91 M MI DATE

ICE CONDENSER i

CONCLUSIONS High level of confidence in our conservative approach Projections indicate the worst case row group will be 116 lbs abouve the Tech Spec limit at the end of cycle Request therefore technically justified

_ - _ _ _ _ _ . - - - - _ _ _ - . . .- _ _ - _ - _ .