ML20141C743

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Insp Rept 50-344/86-06 on 860128-30 & 0224-28.Deviation Noted Re Control Room Emergency Ventilation Sys
ML20141C743
Person / Time
Site: Trojan File:Portland General Electric icon.png
Issue date: 03/21/1986
From: Driscoll J, Hayes J, Willett D, Thomas Young
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML20141C697 List:
References
50-344-86-06, 50-344-86-6, TAC-60941, TAC-61289, NUDOCS 8604070301
Download: ML20141C743 (9)


See also: IR 05000344/1986006

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U.-S.

NUCLEAR REGULATORY COMMISSION

REGION V

Report No.

50-344/86-06

Docket No.

50-344

License No.

NPF-1

Licensee:

Portland General Electric Company,

121 S. W. Salmon Street

Portland, Oregon 97204

Facility Name:

Trojan Nuclear Plant

Inspection at:

Rainier, Oregon

Inspection conducted:

January 28-30, and February 24-28, 1986

Inspectors:

Oh

3- 7/- M

M .'Willett, [

P actor Inspector

Date Signed

.Y h h

% 21 e9 S

J. Hay g, Engineer, ERR Plant Systems

Date Signed

D N MM [

3 2/-Jr 6 .

J. I)(1scoll, Contractfgineer

Date. Signed

Argonne National Laboratory

Approved By:

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3 - y i - f (,

f-

T. Ypnk, Jr. , Chief', Engineering Section

Date Signed

Summary:

Inspection during the period of January 28-30, and February 24-28, 1986

(Report No. 50-344/86-06)

Areas Inspected: Special announced inspection of control room emergency

ventilation system.

Resuloc: In the one area inspected one deviation and three unresolved items

were ide ntified. 'Other enforcement action related to this inspection will be

the subject of separate correspondence.

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DETAILS

1.

Persons Contacted

Licensee

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' Skip Orser, Plant Manager

x*+fGary Zimmerman, Manager, Licensing

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  • x*+fRobert Rupe, Secondary Plant Engineer

x*+@ Henry Goldmann, Mechanical Plant Engineer

+ Bob Schmitt, Manager, Plant Operations and Maintenance

  • x+Al Cohlmeyer, Plant Engineering Supervisor

+ Dick Bennett, Electrical Supervisor

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  • x*+ Scott Bauer, Onsite Licensing Engineer

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x*+f@ William Kershul, Licensing Engineer

$xRich Russell, Assistant Supervisor, Operations

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$ Bud Susee, Operations Supervisor

NRC

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$Jan Norris, NRR

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$ Jim Milhoan, NRR

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$Phil McKee, IE

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$ Dennis Kirsch, Director, Division of Reactor Safety & Projects, RV

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$Tolbert Young, Chief, Engineering Section, RV

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$ Robert Dodds, Chief, Reactor Projects Section 1,107

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$*x*+#@ Jack Hayes, Engineer, NRR Plant Systems Section

$*x*+f@ John Driscoll, Contract Engineer)'Argonne National Laboratory

$*x*+#@ Dennis Willett, Reactor Inspector, Region V, Engineering

fKen Johnston, Trojan Project Manager, NRR

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$fTed Quay, Plant Systems Chief,'NRR

Steve Varga, PWR Project Director No.3, Nlui

  • Denotes those present for January 28, 1986 meeting at Trojan Site.

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+ Denotes those present for January 29, 1986 meeting at Trojan Site.

  1. Denotes those present for January 30, 1986 meeting at PGE, Portland

Corporate Offices.

@ Denotes those present for surveillance test on January 28-29, 1986 at the-

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Trojan Site.

xDenotes those present for February 24, 1986 Entrance meetingaat the site

and Corporate facilities.

' Denotes those present for February 27, 1986 Exit meeting at the Trojan

Site.

$ Denotes those present for February 28, 1986 teleconference in Region V.

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U.-S.

NUCLEAR. REGULATORY COMMISSION

REGION V

Report No.

50-344/86-06

Docket No.

50-344

License No.

NPF-1

Licensee:

Portland General Electric Company

121 S. W. Salmon Street

Portland, Oregon 97204

Facility Name:

Trojan Nuclear Plant

Inspection at:

Rainier, Oregon

Inspection conducted:

January 28-30, and February 24-28, 1986

Inspectors:

Mo.m.4

3 - 7/- fr 6

M Willett,

actor Inspector

Date Signed

.Y h h

3- 2 /-8~ l

J. Haye,4 Engineer, WStR Plant Systems

Date Signed

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J.I)(iscoll,Contractfgineer

Date Signed

Argonne National Laboratory

Approved By: h

8

3 * J / - 8(

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T. Ypng, Jr. , Chief', Engineering Section

Date Signed

Surunary:

Inspection during the period of January 28-30, and February 24-28, 1986

(Report No. 50-344/86-06)

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Areas Inspected: Special announced inspection of control room emergency

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ventilation system.

Results: In the one area inspected one deviation and three unresolved items

were identified. Other enforcement action related to this inspection will be

the subject of separate correspondence.

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DETAILS

1.

Persons Contacted

Licensee

' Skip Orser, Plant Manager

x*+fGary Zimmerman, Manager, Licensing

  • x*+# Robert Rupe, Secondary Plant Engineer

x*+@ Henry Goldmann, Mechanical Plant Engineer

+ Bob Schmitt, Manager, Plant Operations and Maintenance

  • x+Al Cohlmeyer, Plant Engineering Supervisor

+ Dick Bennett, Electrical Supervisor

  • x*+ Scott Bauer, Onsite Licensing Engineer

x*+#@ William Kershul, Licensing Engineer

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$xRich Russell, Assistant Supervisor, Operations

.$ Bud Susee, Operations Supervisor

NRC

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$Jan Norris, NRR

$ Jim Milhoan, NRR

$Phil McKee, IE

$ Dennis Kirsch, Director, Division of Reactor Safety & Projects, RV

$Tolbert Young, Chief, Engineering.Section, RV

$ Robert Dodds, Chief, Reactor Projects Section 1, RV

$*x*+#@ Jack Hayes, Engineer, NRR Plant Systems Section

$*x*+f@ John Driscoll, Contract Engineer, Argonne National Laboratory

$*x*+f@ Dennis Willett, Reactor Inspector, Region V, Engineering

fKen Johnston, Trojan Project Manager, NRR

$$Ted Quay, Plant Systems Chief, NRR

Steve Varga, PWR Project Director No.3, ENRR

  • Denotes those present for January 28, 1986 meeting at Trojan Site.

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+ Denotes those present for January 29, 1986 meeting at Trojan Site.

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  1. Denotes those present for January 30, 1986 meeting at PGE, Portland

Corporate Offices.

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@ Denotes those present for surveillance test on January 28-29, 1986 at the

Trojan Site.

xDenotes those present for February 24, 1986 Entrance meeting at the site

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and Corporate facilities.

  • Denotes those present for February 27, 1986 Exit meeting at the Trojan

Site.

$ Denotes those present for February 28, 1986 teleconference in Region V.

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Emergency Ventilation Survey

The inspectors met with licensee representatives (January 28, 1986),

identified in paragraph 1, to discuss the NRR program for inspecting a

large sample of nuclear plant control room emergency ventilation systems

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and evaluating the adequacy of these systems as designed and built by a

wide variety _of vendors, architects, and constructors.

In addition to an

evaluation of the licensee's request to modify the technical

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specifications to make Specification 4.7.6.1 an annual, instead of

monthly, test, this inspection is an extension of the program submitted

by NRR and IE to the EDO in response'to ACRS concerns: (Control Room

Habitability Working Group Report, June 1984 ) "...that the NRC STAFF's

goal for confirming compliance with existing Regulatory Guides and

Standard Review plan for TMI item III.D.3.4 Control Room Habitability may

not be adequate to protect the control room occupants from radiation,

particularly with respect to leakage control and arrangement of air

intakes...."

The inspectors observed the conduct of the monthly surveillance test

(POT-20-1, Rev.16) for control room emergpacy ventilation system

(4.7.6.1) at the start of, the midnight to 8:00 a.m. shif t (January 29,

1986). The inspector's purpose was to take independent measurements of

temperature and humidity at select locations during the ten hour

surveillance period and chart these changes to determine the adequacy of

the emergency ventilation system with the. normal ventilation system

secured.

During the conduct of the test the inspectors noted several

inconsistencies between how the test was being performed and the

licensee's submittals, FSAR, Technical Specifications, TMI III.D.3.4

response (January 2,1981), SSER (October 1974), ANSI-N510-1975, and

Regulatory Guide 1.52.

In addition, the inspectors identified that the

test was not being performed in a manner consistent with how the system

would be lined up and operated during emergency operation. This is an

apparent violation (86-06-01). After a short time into the surveillance

the inspectors terminated their involvement since, in their opinion, the

surveillance procedure was inadequate and the way the test was being

conducted could not provide any useful information. The following

narrative identifies how the system was aligned and operated during the

conduct of the surveillance test.

The normal ventilation system CB-2 was secured. The emergency

Ventilation system CB-1 was initiated. Dampers 1051 A & B were closed,

these dampers supply outside make-up air (150 cfm) to the heaters and

charcoal filters.

CB-4 & 3, the bathroom vent and laboratory exhaust

fume hood vents and fans, were open and operating exhausting (their

capacity is 4050 and 3740 cfm respectively) out of the control room

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envelcpe. The humidity control for the charcoal heaters was adjusted up

from its current setpoint of 85 to 100%, which means that the heaters

would remain off for any humidity of less than 100%. The inspectors

informed the test engineers and shift manager that a differential

pressure gauge'(outside air relative to the control room), on the back

wall of the control room, was registering off-scale negative indicating

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-that the; control' room was atfainegative, pressure with respect.to the

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The Technical' Specifications l4.7.6.1 states that,?Each control room .

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ventilation system shall.be, demonstrated operable".

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At least once per 31 days,on a STAGGERED TEST BASIS by initiating

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.-flow through the HEPA filter and charcoal adsorber train and

verifying that the train operates for~at least 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with'the

preheaters on and maintains.the control room temperature (110'F.

The BASES for this Technical' Specification states'in 3/4.7.6:

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"The OPERABILITY of the control room ventilation system ensures'that

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1) the ambient air temperature does'not' exceed the allowable

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temperature for continuous duty rating for-the equipment and

instrumentation cooled by this system, and 2) the control room will

remain habitable for operations personnel during and following all

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credible accident conditions. The OPERABILITY of this. system in

conjunction with control room design provisions is -based on limiting '

the radiation exposure to personnel occupying the control room to 5

REM or less whole body, or its equivalent. This limitation is

consistent with the requirements of General Design Criteria 19 of

Appendix "A", 10 CFR 50."-

The Safety Evaluation Report October'1974 states, in section 6.4

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"...Under emergency conditions 150 cfm of filtered pressurized air is

provided to assure a positive pressure inside the control room to limit

the amount of unfiltered air leakage into the' control room." The

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calculated radiation doses to control room personnel following a LOCA to

satisfy General Design Criteria 19, Appendix "A" 10 CFR 50, appear to

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rely upon the positive pressure and. filtered make-up' air features.

The' updated FSAR in section 6.4.2.3 states that, "The control room

ventilation system is' designed'to maintain a 1/8-in. water gauge

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differential pressure with one train of EVS (CB-1)Loperating. A control

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room volume of 81,300 cu ft (section 12.2.2.3) and a make-up ventilation

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flow rate of 150 cfm result in net air leakage rate of 0.11 hr-1 "(The

preceding is also reiterated in PGE's submittal for_III.D.3.4, Withers to

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Eisenhut, January 2, 1981). "... Low leakage dampers are used to isolate-

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the control room emergency zone from adjacent zones and the outside.

Figure 9.4-1 of the FSAR shows the locations of these dampers. The

dampers are designed for a leakage rate of 41 percent, not to exceed

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50 cfa."

'?...Section6.4.4.1.2statesthat7"anupdatedcontrolroom

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radiation analysis has been performed' utilizing the assumptions outlined

in Nuclear Power Plant Control Room Ventilation System for Meeting

General Design Criteria 19" by Murphy'and Campe.

(This document is

identified in NUREG-0737 as guidance for satisfying TMI item'III.D.3.4

Control Room Habitability Requirements). The updated analysis uses

150 cfm filtered makeup with 10 cfm unfiltered ingress / egress.

' FSAR section 9.4.1.2 System description states, '?...The duct work is

arranged to supply 150 cfm of outdoor makeup air and to recirculate

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enough air to provide a total flow of 3200)cfm when one system is

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operating. Low' leakage dampers'are provided which can close off the

supply of outdoor air...."

This section also goes on to say, "...The low

leakage dampers-in the outdoor air' supply to system CB-1 are normally

closed and require manual actuation to open...."

The inspectors were

informed that there were no instructions in any of the emergency

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procedures which. instructed'the operators to open these outside air

dampers. Additionally, the. inspectors were told that following a Safety

Injection signal no makelup air is' admitted for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> (FSAR Section

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The system description. continues, "... Controls in the electric preheat

coils in; system CB-1:are arranged to'en'able;them to. carry out their

design. function which is.co prevent.. air;from entering the filter trains

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at relative humidity' higher.than 90 percent. . If/a humidistat in the

entering air stream shows more than 70-percent relative humidity and flow

switch' establishes that there,is airflow, the preheat coil will be

energized. .It has the capacity.co reduce the relative humidity.of the

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incoming air frta from'100 percentLto 70 percent...."

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Theinspectorsmetwith\\lic'enseerepresentatives(January 29, 1986),

identified in paragraph <1,-to discuss the following concerns:

1.

The preheaters were not'on as per technical specification

requirements. This is an. unresolved item (86-06-02).-

2.

The outside makeup air 4amperg.were closed which would not allow any

positive pressure control with leakage., This is an apparent

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violation (86-06-03).

3.

CB-3 And 4 were not secured which exhausted enough air to make the

control room pressure negative relative to the outside, this is an

apparent violation (86-06-04).

4.

The humidistat was not set as per submittal to NRC. This is an

apparent deviation (86-06-05).

5.

No instruction in the emergency procedures directing operators to

open.the make up dampers when emergency ventilation was required.

6.

The control room envelope differential pressure measurements should.

be relative to the highest' adjacent boundaries relative to the

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control room' envelope. This is an apparent violation (86-06-06)

Th'e licensee stated that they would review these issues and the

circumstances.

The inspectors met with licensee representatives (January 30, 1986),

identified in paragraph 1, to discuss the above concerns. At this time

. the inspectors also held a separate teleconference with NRR Project

Management and Flant Systems Management.-

The licensee had not been able to determine why the humidistats were set

to 85 percent for normal operation when they should have.been set to

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70 percent (70% is consistent with ANSI /ASME N509-1980 section 5.5.1 and

Regulatory Guide 1.52).

The licensee has agreed to do the surveillance test with the humidistats

set to 70 parcent, the makeup dampers.open, the bathroom and lab fume

hood exhaust (CB-4 & 3) secured. The licensee questions the validity of

the Technical Specification which states that the train operates for

10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> with the preheaters on and maintains the control room at < 110*F.

The licensee contends that with the humidstats set at 70 percent

(automatic) that this is equivalent to "0N".

The NRR project management

and Plant systems management take exception to this interpretation and

concur that for the test, the humidstats should be set at zero percent

which would energize the heaters.

The inspectors discussed with the licensee staff, the prudence of

measuring the control room differential pressure relative to the highest

control room boundary, instead of the outside atmosphere, since it is

possible that one of the boundaries could be at a higher pressure than

outside. The licensee committed to measure differential pressure at the

six boundaries for this determination.

The inspectors met with licensee representatives on February 24, 1986, at

the site and the corporate office. The inspectors stated that, based on

preliminary findings of the previous inspection, the purpose of this

return inspection was to obtain additional assurances that the emergency

ventilation system satisfies GDC-19. The inspector expressed the region's

concerns and told the licensee that regional management expected the

licensee to provide an analysis to support their position that the

emergency ventilation system had, in past and current configurations,

met GDC-19. This analysis should also contain some data to support the

assumptions and conclusions (basic data would be relevant air flows and

balances during normal and emergency configurations).

The inspectors discussed with the system engineer and his supervision

what line flow data would be necessary to make an adequate determination

of system performance. The system engineer and inspectors walked the

systems down to find where flow measurements could be taken, from

existing test ports, and to determine the most appropriate point to make

measurements on lines without instrumentation ports.

From this walkdown

the inspectors expressed an additional concern, regardin8 the accuracy of

the licensee's data on system performance and design for surveillance

since many of these lines did not have instrumentation ports to obtain

the necessary minimum data. This is an apparent violation (86-06-07).

Licensee representatives initiated maintenance requests and enlisted

engineering support to install test ports in portions of the normal and

emergency ventilation systems where data would be required to support

analysis of ventilation system performance.

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The inspectors evaluated the suitability of potential test port locations

for adequacy and the potential to obtain reliable representative

readings.

Upon installation of test ports, the inspectors, with calibrated NRC

instruments, took data during operation of the normal ventilation system

and with the emergency ventilation system "0N", while the makeup dampers

were open and closed, and CB-3 & 4 was in different combinations of 0FF

and ON. During these measurements it was discovered that the makeup flow

rate from CB-1B was approximately 460 cfm when it should be a design 150

cfm. This is an apparent violation (86-06-08). The inspectors

terminated their data taking until the licensee could adjust the "B"

system makeup ficw to appropriate values and the "A"

train could be

measured.

Af ter the licensee had adjusted the CB-1 makeup flow to approximately

190 cfm, and was running the monthly 10 hour1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> surveillance test, the

inspectors took another set of data. During these measurements the

inspectors discovered that a two inch drain pipe for the cooling units,

on the downstream side of the filter /adsorbers, was sucking air into CB-1

A & B trains. The inspectors measured approximately 41 cfm flow

(equivalent to approximately 800 cfm filtered flow with a 95 % filter

adsorber efficiency). The drain pipe was connected to both

"A" and "B"

trains with a common outlet (configuration similar to a Y).

This

configuration should have been identified during required visual

inspections of the emergency ventilation system per ANSI-N510-1975. This

is an apparent violation (86-06-09). This configuration conotituted a

common mode failure and a lack of train separation, so the licensee

capped the common line. This new configuration allowed CB-1 A & B trains

to draw makeup from both make up lines at the same time and the system

still lacked train separation. This is an apparent violation (86-06-10).

The licensee initiated steps to have the lines cut and drain valves

installed.

During the period that the licensee was responding to the drain pipe

issue, and while the inspectors were continuing to take data, the

inspectors discovered that fan CB-3 was still operating. This fan was

required to be off during the surveillance test.

The licensee discovered

that, although the indication in the control room indicated that the fan

was OFF, the indication in the control room was really for the damper

position on the discharge of fan CB-1 and not the fan. When the

discharge damper for fan CB-1 is closed it operates a limit switch which

is suppose to cut off power to the fan. The licensee determined that the

limit switch and damper positioning needed to be adjusted relative to

each other.

The inspectors terminated their measurements until the licensee could

solve the system problems, place the system in the appropriate

configuration and complete the system surveillances. The inspectors met

with the plant manager and representatives of his staff, identified in

paragraph 1 on February 27 to discuss their concerns and findings. The

licensee told the inspectors that they were not staffed or instrumented

to deal with the above questions of system performance, and would acquire

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additional resources to assure that these systems were adequate and would

be operated in a manner that would satisfy their intent.

After inspector discussions with regional and NRR management, several

concerns were forwarded to the licensee in a confirmatory action letter,

dated February 28, 1986 (J. Martin to B. Withers). The licensee responded

to the confirmatory action letter March 4,1986 (B. Withers to J Martin).

Based on an evaluation of the findings of this inspection and previous

licensee submittals, Region V has requested that NRR determine if the

emergency ventilation system satisfied General Design Criteria 19

(Appendix "A" to 10 CFR) in past and present configurations. This is an

unresolved item (86-06-11).

During operation of the. emergency ventilation system (CB-1) with the

normal control room ventilation system (CB-2) secured, approximately

600 cfm of flow was measured in the normal makeup air duct. An

additional, 150 cfm of flow was measured in the control room exhaust

(CB-12). The direction of flow in these two measurements could not be

determined with the available instruments.

If the direction of flow was

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out, this would mean that the control room must-be at a negative pressure

relative to the outside because there was approximately 300 cfm more of

exit flow than there is of make up flow.

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The control room is required to be at least a positive 1/8 inch water

gauge differential with respect.to the surrounding boundaries. One

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possible explanation of why the pressure was being measured positive is

the location of the pressure sensing device taps in the duct work. The

pressure differential is being measured between the control room and

inside of the normal ventilation system supply duct. This means that the

pressure gauge is configured so that the low side is connected to the

supply duct and the high side is open to the control room atmosphere.

If

600 cfm of air is exiting this duct this implies that the duct is at a

higher pressure than the outside atmosphere and would cause that gauge to

indicate a lower than actual differential pressure.

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If the direction of air flow is "IN",

the duct pressure is lower than

atmosphere, causing the gauge to indicate that the differential pressure

is higher than actually exists between the control room and outside

atmosphere. This could account for how the control room could be

maintained at a positive pressure with the emergency makeup dampers

closed.

If the leakage is "IN" the estimated thyroid dose, as calculated

by NRR, could possibly be in excess of 900 rem.

Either case is unacceptable because the control room is either operating

at a negative pressure or seeing excessive unfiltered makeup flow. This

is an unresolved item (86-06-12).

3.

Reporting of Events (10 CFR 50.72)

During a review of procedures and documents associated with the emergency

ventilation system, the inspectors reviewed the October 7, 1981, meeting

minutes of the Plant Review Board (PRB). The meeting minutes identified

that PGE personnel had not performed the monthly surveillance

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requirenents for control room habitabi11ty ((110F') between August 22,

1979, and September 18, 1981 (over'two years). .The PRB concluded that:

since the system was capable of maintaining the control room temperature

at 6 110F* on September.1981,,that-the system had been adequate during

the previous tworyears,~and that this constituted a missed surveillance

and was not reportable. This is an apparent violation of reporting

requirements contained in Amendment 21 of the Technical Specifications

(86-06-13)'.>

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4.

Unresolved-Items

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Unresolved items are matters about.which more information is required in

order to ascertain whether they are acceptable items, violations or

deviations. Unresolved items disclosed during the inspection are

discussed in paragraph 2.

5.

Exit Interview

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The inspectors met with representatives (denoted in paragraph 1) on

January 30, and February 27, 1986. The scope and findings of the

inspection, which were discussed during the exit interview are set forth

in paragraphs 1 through 4 of this report.

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