Text

Forwards Meeting Summary of Enforcement Conference Re Insp Repts 50-348/88-05 & 50-364/88-05 on 880525.List of Attendees & Viewgraphs Encl
	ML20151E063
Person / Time
Site:	Farley
Issue date:	07/11/1988
From:	Grace J; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:	Mcdonald R; ALABAMA POWER CO.
References
	NUDOCS 8807250353
	Download: ML20151E063 (33)
	v • d • e

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July 11, 1988 i

Docket Nos. .50-348, 50-364

, ' License'Nos. NPF-2 and NPF-8

Alabama Power Company

ATTN: Mr. R. P. Mcdonald

Executive Vice President

P.O. Box 2641

Birmingham, AL 35291-0400

Gentlemen:-

SUBJECT: MEETING SUMMARY OF ENFORCEMENT CONFERENCE - NRC INSPECTION REPORT.

NOS. 50-348/88-05 AND 50-364/88-05

This . letter refers to the-Enforcement Conference held at our request 'at the

Region II Office on .May 25, 1988. - This meeting concerned activities

authorized by NRC Operating License Nos. NPF-2 and NPF-8 for Farley Units 1

and 2. .The meeting was held to discuss concerns documented in NRC Inspection

Report Nos. 50-348/88-05 and 364/88-05 involvir,g the accumulation of hydrogen

gas in the residual heat removal system crossover piping to the high head safety

injection (HHSI) pum,) and in the HHSI pump suction piping, and the resulting

impact on the operability of the HHSI pumps.

Enclosed is a meeting summary including a list of attendees and a copy of the

handouts provided to the NRC at the meeting.

In accordance with Section 2.790 -of NRC's "Rules of Practice," Part 2,

Title 10, Code of Federal Regulations, a copy of this letter and its

enclosures wil.1 be placed in the NRC Public Document Room.

Should you have any questions concerning this matter, we will be pleased to

-discuss them.

'

Sincerely,

CTM'J. SICNED Bh

,

J. IdLSOll GitACE

J. Nelson Grace

Regional Administrator

Enclosures:

1. Meeting Sumary

2. List of Attendees

.3. Licensee Meeting Notes

cc w/encls: (See page 2)

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Alabama Power Company 2 July 11, 1988

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cc.w/encls:

8. M. Guthrie, Executive Vice President

J. .D. Woodard, Vice President

W. G. Hairston,-III, Senior Vice President

J. W. Gowan, Manager Safety Audit

and Engineering Review

S. Fuher, Supervisor - Safety Audit

and Engineering Review

D. N. Morey, General Manager -

Farley Nuclear Plant

'bec w/encis:

-

NRC Resident Inspector

DRS Technical Assistant

E. Reeves, Project Manager, NRR

Document Control Desk

State of Alabama

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ENCLOSCRE 1

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MEETING SUWARY

On-May 25, 1988, representatives of Alabama Power Company (APCo) attended an

Enforcement Conference at the request of the NRC in the NRC Region II Office

in Atlanta, Georgia. The meeting was held to discuss NRC concerns pertaining

6 .to a.- February 1988 event where a significant amount of hydrogen gas was

' to

discovered in the

the high head -crossover

safety pipingpumps

injection HHSI) (from (charging

the residual heatinremoval

pumps) system (RHR

Unit 1 and

Unit 2 of the Farley Nuclear Plant. LER 88-006-01 was submitted by the

licensee on April 25, 1988 discussing the event. Previous NRC review of this

event and details of the event are documented in NRC Inspection Report Nos.

348,364/88-05. Individuals attending the meeting are listed in Enclosure 2.

The NRC -Region II Deputy Regional Administrator opened the meeting by

reviewing the NRC concerns pertaining to the accumulation of hydrogen gas in

the RHR to HHSI pump crossover piping and the HHSI pump suction piping; and,

the resulting impact on the operability of the HHSI pumps.

The Senior Vice President then gave an opening statement for APCo. He

requested that the NRC consider the time frarre associated with tne pre-

operational testing and HHSI pump shaft failure. He stated that the scope

of the hydrogen formation problem had not been recognized early on and

maintained that calculational techniques available at that time were unable to

predict the subsequent events.

APCo representatives then provided a presentation discussing those topics

indicated in the attached handout which was distributed to meeting attendees

'

by APCo (Enclosure 3). Highlights of this presentation are provided below:

A system description was provided. The history of previous HHSI pump failures

(including the 1980 pump shaft failure), testing, and hydrogen gas fonnation

indications and a sequence of events for the February event were discussed.

The licensee noted that the eventual redesign of the charging pump shaft

corrected the shaft failure problem. The licensee's presentation emphasized

-management's concern with the shaft failure, noting occurrences at other

facilities, and the licensee indicated that the shaft failure problem received

significant management attention.

The licensee discussed the likelihood of pump failure based on the amount of

hydrogen gas entrapped in the crossover piping and amount of gas formed during

normal pump operation. The licensee stated that a value of five percent or

less by volume of gas entrained in the fluid nas a negligible effect on the

pumps'. mechanical performance, with no long or short term effects evident.

Values of greater than five percent added to the propensity for catastrophic

failure. Testing had been performed to establish a maximum amount of

allowable hydrogen to assure that pump damage did not occur. The licensee had

established a venting program to limit hydrogen to less than this maximum

amount (6.0 cubic feet) which should limit the void fraction to less than

5 percent as an interim measure. Details of plant modifications to provide

a

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Enclosure 1 2-

venting for the pump suctions and a loop seal to prevent hydrogen formation in

the crossover piping were presented. -The modifications have been completed

for Unit I and will be installed on Unit 2 during the next refueling outage.

The effect of hydrogen on the pumps was discussed and additional information

was presented on the effects of the loss of the HHS1 during a large and a

small break loss' of coolant accident. The licensee maintained that the

ability to safely bring the plant to a safe shutdown condition was

insignificantly effected.

The licensee's presentation on the _ effect of the hydrogen gas on the charging

pump provided no conclusive evidence that the pumps would not fail due to the

flow of gas which would have occurred when the pumps were started during the

recirculation phase. The licensee did state that the "charging pump may

survive" the surge of gas during recirculation. In addition, the NRC pointed

out that Operating Change Request 2-3514, dated November 6, 1979, had

documented the potential for the problem and had recommended further review.

The licensee -provided no new information to indicate that reviews of the

accumuation of hydrogen gas in the crossover piping had been conducted prior

to the February 1988 event.

The NRC is presently considering enforcement action on this issue. This

meeting served to enhance the NRC's understanding of the event and corrective

actions taken to assure operability of the HHS! pumps.

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ENCLOSURE 2

LIST OF ATTENDEES

Alabama Power Company Representatives:

S. Fulmer.-Supervisor Safety Audit and Engineering Review Group- ^

W. Hairston, III, Senior Vice President - Nuclear Support

R. Mcdonald, Executive Vice President - Nuclear Operations

B. McKinney,-Manager, Licensing

D. Morey, General Manager - Farley Nuclear Plant (FNP)

J. Woodard, Vice President, FNP ,

Vendor Representatives:

,

J. Cononie, Plant De:,ign Group Supervisor, Bechtel ;

C. Eicheldinger, Project Manager, FNP, Westinghouse

W. Engel, Mechanical / Process Group Supervisor, Bechtel

J. Grigsby, Nuclear Safety Engineer, Westinghouse

M. Hitchler, Manager, Plant Analysis, Westinghouse

D. Kitch, Principal Engineer, Westinghouse

J. Love, Assistant Project Engineer, Bechtel

R. Moyee, Fluid Systems, Westinghouse

B. McIntyre, Manager, Product Licensing, Westinghouse

S. Prokopovich, Systems Engineer, Westinghouse

NRC Representatives:

E. Adensam, Proj9ct Director, Directorate II-1, Division of Reactor

Projects I/II, Office of Nuclear Reactor Regulation (NRR) '

B. Breslau, Reactor Inspector, Operational Programs Section (OPS), Division of

ReactorSafety(DRS)

H. Dance, Chief, Project.s Section IB, Division of Reactor Projects (DRP)

0. DeMiranda, Allegation Coordinator, Enforcement and Investigation Coordination Staff

(EICS)

M. Ernst Deputy Regional Administrator

A. Gibson, Diractor, Division of Reactor Safety

R. Goddard, Regional Counsel

G. Jenkins, Director, EICS

C. Julian, Chief, Operatiuns Branch, DRS

B. Miller, Jr., NRC Resident Inspector - FNP, DRP

L. Modenos, Project Engineer, Projects Section 18, DRP

T. O'Connor, Reactor Engineer, OPS, DRS

E. Reeves, Senior Project Manager, NRR

L. Reyes, Director, Division of Reactor Projects

M. Shymlock, Chief, OPS, DRS

L. Slack, Assistant, EICS

D. Starkey, Reactor Engineer, OPS. DRS

0. Verre111, Chief, Reactor Projects Branch No. 1 DRP

L. Watson, Reactor Engineer, CPS, DRS

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ENCLOSURE 3

LICENSEE MEETING NOTES

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Agenda for May 25, 1988

APCo - NRC Rydrogen Accumulation Meeting

1. Introduction and Overview

2. System Description

3. History and Sequence of Events

4. Engineering Support Sequence of Events

5. Basis for Short Term Corrective Action

6. Postulated Consequences of Gas Accumulation

7. Conclusion

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J.M. FARLEY NUCLEAR PLANT- -

'

_ CVCS

( CTMT. SUMP ~ PUMP SUCTION

'

8811A 8706A

D 8817A HX

RWST RHR PUMP

- ! HCV603A

8809A

CVCS

( CTMT. SUMP PUMP SUCTION

' 88118 8706P

RHR

8812e HX

B

08

VCT 8809e \

_7 RHR HX As

"

jg DISCHARGE '

CHARGING PUMPS

LCVi15C d X

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8132A

LCV1150

LCv115E

81328

81308

[B *

N_.

8131A 813M

8133B

81318

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, fC

LCVl150

RHR HX Bs

DISCHARCE '

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SUMMARY OF ISSUES l

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H2 GAS MAY ACCUMULATE IN TWO LOCATIONS

1) PUMP 2B SUCTION PIPING

2) A TRAIN RHR TO CCP CROSS-TIE

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EVALUATION OF MECHANISM

0 HYDR 0 GEN OVERPRESSURE IN VCT ;

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O VAPOR PRESSURE = PRESSURE VCT

0 TRADITIONAL CALCULATIONAL TECHNIQUES

UNABLE TO PREDICT THE EVENT

0 LOCAL EFFECTS

0 PIPING LAYOUT

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FARLEY I HORIZONTAL PIPING ELEVATIONS

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FARLEY 2 HORIZONTAL PIPING ELEVATIONS

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INITIAL RECOMMENDATIONS

0 INITIATE A VENTING PROGRAM TO LIMIT H 2

GAS IN RHR TO CCP CROSS-TIE TO LESS THAN

6.0 FT3

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PRECLUDES CATASTROPHIC FAILURE

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EXPECTED TO LIMIT VOID FRACTION TO

BETWEEN 5% - 10%

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UNCERTAINTY OF STRATIFIED 2-PHASE

FLOW ACCELERATION

O

CCP B & C SHOULD BE THE OPERABLE PUMPS

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MINIMIZE ACCUMULATION IN RHR TO CCP

CROSS-TIE

O

CCP 2B SHOULD PROVIDE NORMAL CHARGING

DUTY

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PREVENTS ACCUMULATION IN 2B SUCTION

PIPING

0 EVALUATE A VENTING PROGRAM

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PLANT MODIFICATIONS

1) LOOP SEAL IN "A" PUMP SUCTION PIPING

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UNIT 1 INSTALLED

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UNIT 2 NEXT REFUELING OUTAGE

2) SAMPLING VENTS IN EACH CCP SUCTION

PIPING

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UNIT 1 INSTALLED

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UNIT 2 NEXT REFUELING OUTAGE

3) UNIT 1 VENTING (WITH LOOP SEAL)

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LOOP SEAL APPEARS TO BE EFFECTIVE

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ADDITIONAL TESTING

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LOOP SEAL IN "A" PUMP SUCTION PIPING

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TEST VERIFICATION

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1) OBJECTIVE - DETERMINE IF THERE IS AN

ALLOWABLE VOLUME OF H2 GAS, WHICH IF

ACCUMULATED IN THE RHR TO CCP CROSS-TIE

WILL LIMIT PUMP VOID FRACTIONS TO LESS i

THAN 5%

2) TEST FACILITY

3) CONCLUSION: 6 FT3 WILL LIMIT PUMP

VOID FRACTION TO LESS THAN 5% (I.E., NO

POTENTIAL FOR PUMP DAMAGE

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HDLDING

VATER SUF2 FACE

(375 GALLONS)

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AIR INJECTION TAP

12 INCH

. LEVEL HETER

f ./ u

4 INCH + DIRECTION DF FLOV

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CLEAR PVC PIPE

VUID

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SECTION

2 INCH r

PVC PIPE

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PUHP 4 INCH

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TEST

n@ TEST LOOP SCHEMATIC

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EFFECT OF GAS ON CCPS

1. LONG TERM FAILURE IS DUE TO SHAFT CRACK

PROPAGATION.

2. SHORT TERM FAILURE DUE TO LOSS OF LUBRICATION.

3.<5%GASVOLUNEHASNEGLIGIBLEEFFECTON

MECHANICAL PERFORMANCE

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BASED ON CONSERVATIVE INDUSTRY PRACTICE

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NO LONG OR SHORT TERM EFFECTS

4. > 5% (VITH ADEQUATE LUBRICATION)

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LONG TERM ISSUE

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UNKNOVN SHORT TERM EFFECTS

5. > 5% (VITHOUT ADEOUATE LUBRICATION)

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LONG AND SHORT TERM ISSUE

ALTHOUGH THE PUMP MAY ONLY RUN FOR A SHORT

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PERIOD OF TIME VITH NO VATER LUBRICATION,

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SMALL AMOUNTS OF WATER VILL EXTEND THE TIME

CONSIDERABLY.

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ENGINEERING EVALUATION OF EFFECT

OF

GAS ON TRAIN A RECIRCULATION PHASE

THE CHARGING PUMP MAY SURVIVE THE FLOV 0F GAS

DURING RECIRdVLATION (N0 SHORT TERM FAILURE)

PUMP A IS THE PRIMARY A TRAIN DESIGNATED PUMP

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LAYOUT V00LD PERMIT SOME MIXING OF H 2 GAS AND

WATER PRIOR TO REACHING PUMP SUCTION

1A AND 2A PIPING ARE SELF VENTING

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SEQUENCE OF EVENTS (A PUMP RUNNING)

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INITIAL CONDITIONS

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RHR PUMPS STARTED

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H, GAS COMPRESSION / ACCELERATION

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PARTIAL MIXING AT RVST/RHR TEE

s

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H SLUG ENTERS PUMP AND DEVELOPED HEAD FALLS

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SUCTION PIPING REFLOODED AFTER A PERIOD OF

TIME

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RHR DISCHARGE PUMP ASSISTS IN RE-PRIMING

CHARGING PUMP

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IF PUMP HAS NOT TRIPPED OUT, HEAD CAN

REC 0VER AND PUMP MAY CONTINUE TO PUMP AGAIN

PROVIDING LUBRICATION. H

2

GAS EVENTUALLY

PURGED.

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CONCLUSION: THE PUMP MAY SURVIVE THE

INITIAL EVENT WITHOUT CATASTROPHIC (SHORT

TERM) FAILURE.

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HHSI RECIRCULATION IS A SHORT TERM

OPERATION.

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KEY POINTS

1. TRADITIONAL CALCULATIONAL TECHNIQUES UNABLE TO

PREDICT THE MECHANISM.

2. < 5% VOID NO EFFECT ON PUMP.

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3. >> 5% UNKNOVN EFFECTS ON LONG TERM OPERATION.

4. SHORT TERM FAILURE IS DUE TO INADEQUATE

LUBRICATION.

5. < 6 FT 3

IN RHR TO CCP A HEADER VILL PREVENT BOTH

LONG AND SHORT TERM FAILURE.

6. THE CHARGING PUMP MAY SURVIVE SURGE OF GAS

DURING RECIRCULATION. (N0 SHORT TERM FAILURE)

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RETROSPECTIVE PLANT RESPONSE TO POTENTIAL INCIDENTS

INTRODUCTION

THE CHARGING PUMP MAY NOT' FAIL DUE TO THE

PASSAGE OF HYDROGEN.

.

THIS ASSESSHENT LOOKS AT VHAT HAPPENS IF A PUMP

DID FAIL.

THE PUMPS VHICH ARE POSTULATED TO BE AFFECTED

ARE:

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2B DUE TO ACCUMULATION IN SUCTION -

INJECTION PHASE ISSUE

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"A-TRAIN" DUE TO ACCUMULATION IN THE RHR

CROSS-TIE - RECIRCULATION PHASE ISSUE.

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A. INJECTION PHASE ISSUE

1. H2 IS NOT EXPECTED TO ACCUMULATE IN DAMAGING

AMOUNTS IN THE 2B CHARGING PUMP SUCTION.

0 2B, IF OPERABLE, IS KEPT RUNNING WHICH SWEEPS

THE H2 FROM THE SYSTEM.

o THE TIME WHEN 2B IS OPERABLE BUT IDLE IS

INFREQUENT AND OF SHORT DURATION. LITTLE OR

NO GAS ACCUMULATION IS EXPECTED.

0 2B IS VENTED PRIOR TO RETURNING FROM IDLE TO

CHARGING DUTY.

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RECIRCULATION PHASE FAILURE

THE ACCUMULATION OF GAS IN THE "TRAIN A" RHR TO

CHARGING CROSS-TIE COULD 'ONLY AFFECT THE "TRAIN

A" CHARGING PUMP.

TWO TRAINS OF ECCS ARE OPERABLE, THE DESIGN

BASIS ASSUMES ONLY ONE TRAIN OPERATES.

THE RANDOM FAILURE OF AN ECCS TRAIN (LOSS OF

POVER, RHR PUMP FAILS TO RESTART) WOULD AFFECT

BOTH TRAINS EQUALLY.

IT IS LIKELY THAT THE "B TRAIN" V0ULD BE

AVAILABLE, THUS HEETING THE DESIGN BASIS.

ONLY THE FAILURE OF "TRAIN A" DUE TO GAS, AND A

RANDOM FAILURE IN "TRAIN B" VILL LEAVE NO BHSI

RECIRCULATION CAPABILITY.

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B. RECIRCULATION PHASE ISSUE

1. HYDROGEN ACCUMULATION IN THE RHR TO CHARGING

CROSS-TIE DOES NOT AFFECT THE MITIGATION OF A i

LBLOCA AND HAS ONLY A SMALL AFFECT ON THE

MITIGATION OF A SBLOCA.

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0 LBLOCA DEPRESSURIZES THE RCS TO LHSI CUT-IN

PRIOR TO RECIRCULATION.

O RELIABILITY OF THE SBLOCA MITIGATION IS

REDUCED SLIGHTLY.

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IF OPERATORS TAKE ACTION, THE RELIABILITY

OF MITIGATING A SBLOCA IS REDUCED BY LESS

THAN ONE PERCENT.

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2. ACCIDENT EVENTS ARE NOT EXPECTED TO BE A RISK TO

THE PUBLIC.

(A) LARGE BREAK LOCA:

0 THE RCS DEPRESSURIZES TO LHSI CUT-IN PRIOR TO

RECIRCULATION

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(B) SMALL BREAK LOCA:

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0 E0PS (ES-1.2) WILL START TO

COOLDOWN/DEPRESSURIZE THE RCS

DURING THE ECCS INJECTION PHASE.

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l - CHARGING /HHSI MAY BE THROTTLED OR

TERMINATED DURING THE C00LDOWN.

- RCS DEPRESSURIZATION TO ACCUMULATORS

AND THEN LHSI CUT-IN IS EXPECTED PRIOR TO

RECIRCULATION FOR MOST BREAK SIZES.

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IF NOT, LOSS OF ALL HHSI CASE STUDIED

DURING WOG ERG DEVELOPMENT WILL BOUND THE

LOSS 0F HHSI RECIRCULATION.

RCS COOLDOWN/DEPRESSURIZATION WILL

CONTINUE TO ACCUMULATOR AND THEN LHSI

CUT-IN. NO DEGRADED CORE CONDITION IS

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EXPECTED.

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RETROSPECTIVE PLANT RESPONSE TO POTENTIAL INCIDENTS

CONCLUSIONS i

INJECTION PHASE:

o NO DAMAGE TO THE ECCS IS EXPECTED SINCE HYDROGEN

DID NOT ACCUMULATE IN DAMAGING AMOUNTS IN CHARGING

SUCTION.

RECIRCULATION PHASE:

o RCS WILL ALLOW RECIRCULATION ON THE LHSI PUMPS FOR

MOST LOCA PRIOR TO RECIRCULATION.

o LOSS OF HHSI RECIRCULATIO., EXPECTED TO BE HANDLED

BY E0Ps WITHOUT ALLOWING DEGRADED CORE CONDITIONS

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FARLEY CHARGING PUMP RELIABILITY ASSESSMENT

Results:

Farley experience is equal to or better than industry record.

No cannon-cause failure modes seen at Farley.

Leading Pump Failure Causes

- Shaft Failures * - Seal Leaks

- Vibration - Lubrication cooling / pump problems

- Bearing Wear - Motor / Gear problems

Experience in All Years

Industry Farley

Failure rate 1.3(-4)/hr(NPRDS) 1.3 (-4; (NPRDS *)

5 failures not in NPRDS added

Experience since 1981

Industry Farley

Failure rate 1.6 (-4)/hr 1.1 (-4)/hr (NPRDS)

Failure probability 0.0033 0.0021

(24-hrmission)

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PROBABILISTIC ASSESSMENT OF IMPACT

ON SMALL LOCA MITIGATION

FAILURE OF TRAIN A HPSI PUMP OCCURS DURING RECIRCULATION

PHASE; INJECTION PHASE IS NOT IMPACTED

MITIGATION OF SMALL LOCA EVENT REQUIRES 1

1. HIGH PRESSURE INJECTION

2. A) HIGH PRESSURE RECIRCULATION

0 CONTAINMENT SUMP VALVES OPEN

0 LOW PRESSURE PUMPS FEED HIGH PRESSURE PUMPS :

0 HIGH PRESSURE PUMPS PROVIDE FLOW TO RCS

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B) DEPRESSURIZATION AND LOW PRESSURE

RECIRCULATION

THREE HIGH PRESSURE PUMP CASES EXAMINED:

A. N0 HYDR 0 GEN IN SYSTEM (BASE CASE)

B. HYDR 0 GEN FAILS HPSI PUMP A AT RECIRCULATION -

NO CREDIT FOR HPSI PUMP B

C. HYDR 0 GEN FAILS HPSI PUMP A AT RECIRCULATION -

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OPERATOR ACTION TO ALIGN HPSI PUMP B TO TRAIN A

RESULTS:

FAILURE OF HPSI PUMP A DURING RECIRCULATION DUE TO

HYDR 0 GEN ACCUMULATION DOES NOT ADVERSELY IMPACT

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MITIGATION OF A SMALL LOCA

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SMALL LOCA EVENT TREE

HIGHLIGHTING RECIRCULATION PHASE

ET1 HHI SHP LHS HHR DEP LHR

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1 SUCCESS

, 2 SUCCESS

..- I 3 CM

4 CH

5 CM

6 CH

_-_ 7 CM

EVENT EVENT NAME

ET1 INITIATING EVENT

leil HIGH HEAD INJECTION

SMP SUMP VALVES OPEN

LHS LUV HEAD PUMPS RESTART IN RECIRC

HHR HIGH HEAD RECIRCULATION

DEP DEPRESSURIZATION UCCURS

LHR LDV HEAD RECIRCULATION

PLRA058

05/I7/88

-

. .

.

SMALL LOCA

CORE DAMAGE FREQUENCY ESTIMATES

CASE DESCRIPTION CORE DAMAGE PERCEP.

FREQUENCY CHANGE

BASE NORMAL SYSTEM OPERATION 2.18E-05 -

.

(NO PUMP DEGRADATION

DUE TO HYDROGEN)

1 CHARGING PUMP A FAILS 2.52E-0 16

DUE TO H2 (NO CREDIT FOR

ISOLATED CHARGING PUMP B)

2 CHARGING PUMP A FAILS 2.19E-05 <1

DUE TO H2 OPERATOR

ACTION TO REALIGN

CHARGING PUMP B)

l

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

_ _ _ -__ _ _ _ _ _ ___

-.

! ..

.

'

SMALL LOCA -

! ACCIDENT SEQUENCE COMPARISONS

l

l S50. No. SEQUENCE DESCRIPTION _

--

BASE CASE 1 CASE 2

1 FAILED NODES) FREQUENCY FREQUENCY FREQUENCY

l 3 ET1 HHR LHR 3.35E-10 4.79E-08 1.16E-09

l (<1%) (<1%) (<1%)

l

4 ET1 HHR DEP 2.35E-08 3.36E-06 8.13E-09

(<1%) (13%) (<1%)

5 ET1 LHS 2.46E-06 2.46E-06 2.46E-06

(11%) (10%) (11%)

6 ET1 SMP 1.06E-05 1.06E-05 1.06E-05

(49%) (42%) (48%)

7 ET1 HHI 8.80E-06 8.80E-06 8.80E-05

(40%) (35%) (40%)

TOTALS 2.18E-05 2.52E-05 2.19E-05

.

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

ML20151E063

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