ML050840064

Operating Experience Table

ML050840064
Person / Time
Site:	Point Beach
Issue date:	03/21/2005
From:	- No Known Affiliation
To:	Office of Nuclear Reactor Regulation
References
FOIA/PA-2004-0282
Download: ML050840064 (12)

Text

Operating Brief Description Group Actions Taken To Address Experience OE 31454 OE16368 - Airline Breathing Hood Fitting; RP The CJEN fittings are double Hope Creek event - worker in bubble hood acting fittings approved by lost air when fitting unexpectedly NIOSH per the disconnected manufacturer.

OE48685 OE13365 - Two Separate Incidents where RP The CJEN fittings are double Loss of Breathing Air to Air-supplied acting fittings approved by Respirator (one due do disconnect fitting; NIOSH per the one due to accidental cutting of air hose manufacturer.

The previous incident at PBNP was due to utilizing a make-shift steps that cut into the hoses. The designed steps are in place for the job and do not pose a cutting issue.

To be covered in the lesson plan.

OE 10321 OE16908 - Separation of Air Line Coupling RP The CJEN fittings are double on Supplied Air Hood A worker wearing a acting fittings approved by supplied air hood experienced a loss of air NIOSH per the supply to the hood. The cause of the event manufacturer.

was a quick-connect coupling in the worker's air supply line that became The RP technicians will be unthreaded. During the event, the on the same channel as the maintenance technician had moved out of workers (radios). RP will line-of-sight contact with the HP technician.

have a designated person

• T

When he lost air, he attempted to contact responsible for standby-the HP technician but was unable to do so.

rescue. (removal of the The maintenance technician returned to the bubble hood) step-off pad, where a second mnt. worker noticed his distress. The second worker attempted to contact HP via radio, but was not successful since maintenance radio communication frequencies were not compatible with those of HP.

SER 20-82 Zion Unit I Failure to Remove Steam Eng Klesper - Do we do an Generator Nozzle Cover Following Prog equipment audit after Inspection Hinge parts were accidentally removing nozzle dams? We left in use an FME log. And log all pieces. We close out per SEN 7.1 1.11 Are there nozzle dam parts that could get left behind? All sub-parts are secured. Note that this SER left cover in and the startup forces blow the cover to pieces, only the SS hinge remained.

Discussion of FME concerns specifically relating to this SER and the SER are listed in the lesson plan.

CAP 46796 OEI 1729 - Bubble Hood Airline Disconnect Vulnerability with Single Lock Air Connect RP The new connections (CJEN) are manufactured on the hoods. They are double acting connections to reduce the possibility of

disconnection.

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1-SEN 205 Recurring Event RCS Inadvertently Drained below Top of Hot Legs PI drained to install nozzle dams and drained too faro Ops Drain Down Procedure satisfactory?

During this evolution this time (Draining the cavity down to mid loop) we don't use Nitrogen overpressure so this is not a concern. We could however push approximately 350 gals out of the vertical section of the cold leg due to nozzle dam air leak through. This is covered in Item 25 INPO OE San Onofre used a TOMCO disconnect IH&S CJEN fittings are NIOSH 10197 which was not on the NIOSH approved list approved, as per the manufacturer.

261-Nose Cone of Block and Tackle used to Eng How do we control the 991004 install nozzle dams falls into S/G Hot Leg Prog equipment we use to remove nozzle dams from an FME perspective? Everything is logged in and out. People power is used to lift dam in.

We do not use block and tackle.

SER 03-02 Workers Exit Site with detectible RP This is not in the lesson plan OE 51051 contamination - RP techs assumed frisker since those that will be CAP 31288 and portal alarms were caused by internal performing this step are not CAP 31595 rather than external contamination in the class.

OE 9576 Perry Plant - Intermixed MSA/Foster Hose RPAIH As per the bubble hood lines with NPO/Schradcr Hose lines causing S

manufacturer instructions bubble hood to not be NIOSH approved.

included with the bubble hood the CJEN fitting is acceptable.

OE 9243 Vermont Yankee - Bubble hoods NIOSH RP/IH As per the bubble hood Certified with Hanson fittings. Vendor S

manufacturer instructions claimed Foster fittings were an acceptable included with the bubble substitute. NIOSH said no only Hanson hood the CJEN fitting is fittings.

acceptable.

CAP 55527 Individual experience low air pressure to RP/

Discussed during Lesson bubble hood Prog Plan Individual air supply line disconnected Eng Corrective actions associated white in SG with the nozzle dam events:

Individual air line disconnected upon I. Brought in an independent attempted bowl entry team of NMC folks (Don Individuals air supply line damaged/cut Schuelke, corp RP and Joe Hager, Pallisades) to review our procedures and processes for use of supplied air as breathing air.

2. Used their input to:

a. Update applicable procedures (temp changes issued) (included manifold pressure vs hose section table)

b. Recognize that it was unsat to have nitrogen backup bottles inconnected to

the breathing air system via the nozzle dam control panels. We had the bottles changed out and replaced with certified Grade D Breathing air.

c. Replaced all of our bubble hoods, airlines and fttings to new CEJN type fittings -- these fittings won't pop open, you have to push and pull them to open.

3. We also developed a Just in Time information sharing package to be used in conjunction with the prejob briefing for reator vessel head work. This included a review of our procedure requirements, bubble hood issueance requirement, and manifold pressure requirements.

These items were completed and we used bubble hoods very successfully on Friday 4/23 to perform hydrolazing decon of the reactor vessel underhead.

We have also conducted flow testing through the breathing air hoses to confirm design air flow versus manifold pressure.

l CAP 55682 During placement of robotic equipment in the steam generator channel heads a worker received a dose rate alarm on his electronic dosimetry. As the workers exited the work area it was discovered a 2nd worker had received a dose rate alarm.

Similar to Sen 233, not specifically covering.

CAP 56147 Individual Exceeded Overtime Limits All Discuss during planning without proper approvals process Ask at pre-job brief CAP 55537 NOS identified the posting of the Nozzle Eng How do we limit work not to Dam Control Panels inside U-1 Prog jeopardize air hoses?

Containment was inadequate and that Protected equipment status.

scaffold construction was occurring nearby.

The the scaffolding in this CAP is 5' away. The OCC did permit work on it.

What postings do we need to change? None. Ops is require to take down the Protected Equipment sign. A sign was hung on the equipment, but NOS asked for it to be moved to a cone infront of the panel.

CAP 55547 Procedure controls for nozzle dam Ops Procedure changes were installation are weak made to OP-4F per CE 013755.

CAP 55705 Nonpermit confined space analysis form not Work Currently posted promptly posted planne r

CAP 55896 Unit I "A" Steam Generator Handhole Work Setup access in work Platform planne plan/schedule r

CAP 55751 Service Air for Breathing Air - is it IHS Resolved resolved?

CAP 55645 Bubble Hoods not issued in accordance with RP Issuance of the bubble hood HPIP 4.58. The procedure requires the is covered in the lesson plan.

issuance to be documented on PBF-4234 and this was not completed.

CAP 55560 NP 8.4.9 Hose Control requires yellow air Eng The Cap is to address hoses, some vendor hoses are red Prog vendor hoses. PBNP procedure states air hose will be yellow. This is not a universal standard. PBNP procedures don't' address vendor hoses well. The yellow tape is a compromise and should be incorporated in the procedure as recommended.

CAP 55825 In Unit I containment, there is an air hose Eng Will we add any new hoses?

connected to the "A" Steam Generator Prog Do we need to add routing Nozzle Dam Control Panel that runs along info? Will we add any new the stairway and into the stairs.

hoses? NO Do we need to add routing info? NO, not on removal.

CAP 49234 Recurring Event-Personnel Exposure Exceeds RP Cover in lesson plan as SEN 233 Electronic Dosimeter Alarm Setpoint On March operating experience.

23, 2002, with Nine Mile Point Nuclear Station Unit 2 shutdown for refueling, contract personnel radiation dose exceeded the planned dose and the dosimetry alarm setpoint for a specific task. This was not recognized until they exited the work area. In addition, the TLD dose value for one worker was 359 mrem greater than the electronic dosimeter reading.

CAP S/G Nozzle Dam Installation Dose Eng Do we have this properly 55587/

Exceeded Estimate/ Use Jump platform Prog planned? Is it a checkoff in OTH57189 the workplan? Yes the alara estimate is revised and there is a sign off for the steps. Is it a checkoff in the workplan? Yes for steps CAP 45040 Potential Loss of RHR Cooling During Ops OE 45043 evaluated this as Nozzle Dam Removal (Part 21) ok for PB. Is this eval still DURING REFUELING ACTIVITIES, NOZZLE DAMS ARE good? "If the nozzle darn wet seal COMMONLY USED TO ISOLATE THE SGS IN ORDER TO PERFORM MAINTENANCE ACTIVITIES WHILE THE leaks (even a small leak), air can fill up REACTOR IS BEING REFUELED. NOZZLE DAMS THAT the vertical section of the cold leg UTILIZE INFLATABLE SEALS AS THlE PRIMARY SEALING replacing the water. This volume is MECHANISM MAY CREATE A TRAPPED AIR COLUMN about 47 cubic feet. This leak may or BEHIND THE COLD LEG NOZZLE DAM. T)IlS AIR may not be detected by the periodic COLUMN COULD BE CREATED BY UNDETECTABLE monitoring done by OPs using PBF-MINUTE LEAKS OF AIR THROUGH THE INFLATABLE 2021 depending on the size of the SEALS WHICI I ARE TYPICALLY PRESSURIZED TO 65 leakA\\lf this occurs, air under a few PSIG (ALMOST 5 TIMES THE HYDROSTATIC PRESSURE PSI of pressure woulder and CAUSED BY THE REFUELING POOL WATER).PSI of pressure would be trapped and CONTINUAL LEAKAGE OF AIR INTO TIlE COLD LEG when the nozzle dams are WOULD EVENTUALLY EVACUATE TIlE VERTICAL depressurized and removed at 3/4 pipe, PORTION OF TllE COLD LEG LEADING TO TIlE RCS this air volume would be replaced by PUMP. TIllS EVACUATION OF WATER COULD OCCUR water from the RCS. A brief WITHIN A 7.DAY PERIOD. HAVING AN AIR COLUMN IN calculation was done and this volume PLACE OF WATER MEANS THERE IS LESS WATER of air being replaced would result in an AVAILABLE FOR COOLING DURING MID-LOOP RCS level decrease of about 2 inches CONDITIONS. REMOVAL OF TIlE COLD LEG NOZZLE from 314 pipe for one nozzle dam. This DAM WOULD RELEASE TllS TRAPPED AIR COLUMN is not a significant safety concern with AND COULD CAUSE T IE RCS INVENTORY TO is notaigifcatafty______it

l SUDDENLY DECREASE TO A LEVEL BELOW THE RIIR SUCTION LINE CAUSING A RISK OF VORTEXING/CAVITATION OF T IE RI IR PUMPS AND SUBSEQUENT LOSS OF RIR COOLING r regard to the possibility of losing RIIR duc to loss of suction, but it is something that the operators should be aware of and anticipate the possibility when nozzle dams are being removed.

Precaution and Limitation 3.1 of OI-I "Steam Generator Nozzle Dam Operation Guide" discusses this possibility and what could occur oln drain down.

PBF 2021 Nozzle Dam Log also records air flow to the nozzles. A small leak could air load the pipe but would not impact RHR operations.

A larger air leak would not go undetected. A caution has been placed in OP-4F to alert the operator of the possibility of losing some vessel level (approx 350 gals) upon removing each of the cold lea nozzle dams.

OE 12483 Steam Generator Nozzle Dam Diaphragm Eng Do we have Scientech NES Bolt Hole Misalignment The first two of Prog Type WR Steam Generator eight installations took over three times the (SG) Nozzle Dams (ND)?

anticipated time to install successfully.

Do we have Scientech NES Installer observations were that the bolts Type WR Steam Generator that secure the nozzle dams to the retaining (SG) Nozzle Dams (ND)?

ring were difficult to engage and required Yes, wve also have new more time to tighten.

diaphragms. Doe not apply

to removal. Note this is similar to the problem we had with'installation. We had a bad bolt hole. To ensure this will not happen in the future, we have a picture of the orientation that worked.

• Group responsible to review and implement the operating experience.

Important Considerations Prior to SIG Nozzle Dam/Cover Installation and Removal (Lessons Learned)

Workers and Supervisors Oi What methods do we use to document items brought into the steam generator? What level of detail is recorded?

O Prior to installing nozzle dams or nozzle covers, what methods are used to prevent items from falling into the reactor coolant loop (e.g., lanyard, adhesive tape, and container for small items)?

Q Which reactor coolant leg should the first nozzle dam be installed and under what condition is this applicable? What is the reason? (If the reactor vessel head is installed, the cold leg nozzle dam should be installed first and the hot leg should remain open to provide an adequate vent path to reduce the possibility of developing a pressure differential sufficient to eject reactor coolant from the steam generator cold leg opening.)

What methods and equipment do we use to monitor reactor coolant leakage from nozzle dams? Who is responsible for monitoring? How often are the dams monitored for leakage?

How have we verified the main and backup air systems are functioning properly? Who is responsible for testing and monitoring the air systems? How often are the air systems monitored?

What contingency plans have wve developed if a nozzle dam leaks?

How do we verify that all nozzle dam equipment and tools are removed from the steam generator? Who is responsible for performing an independent verification? How is the verification performed?

How do we verify that contractors installing nozzle covers or dams understand the station's requirements on foreign material exclusion?

O How do we verify that contractors have been informed of in-house and industry-related operating experience on nozzle dam work activities? How is the information communicated to contractors?

Engineering What redundancy have we designed into systems that support the operation of nozzle dams and reduced the likelihood of deflating the seals? Protected equipment on Service Air Supply, backup compressed air, check valves at dams, passive seal How have we verified that the size of the vent path is adequate to prevent overpressurizing the nozzle dams when the reactor vessel head is installed? See SCR 2003-329 What are the nozzle dam design limitations with respect to pressure differential? Which direction is more limiting (water side or air side)? Test pressure 34.2 psi, over pressure 65 psi refer to Scientech document 83A7564 page 14. Air side in not applicable.

t I..

V What methods do we use to prevent bayonet insert pins from migrating into the reactor coolant system (if inserts are used)? What methods do we use to verify the insert pins have not degraded? How often and when are the verifications performed? We do not use bayonet connector with any SG Radiological Protection and Industrial Safety Q

How have we verified that the air line fitting to the bubble hood air supply tubing we are using meet National Institute for Occupational Safety and Health requirements? How have we trained our personnel to be knowledgeable of this type of air line fitting?

Q How have we verified that the workers are proficient installing nozzle dams and nozzle covers? Have we considered using a mock up?.

11 How have low dose radiation areas been identified or posted for this job?