IR 05000201/1978012

IE Insp Rept 50-201/78-12 on 781212-13.No Noncompliance Noted.Major Areas Inspected:Circumstances & Actions Re Discovery of Defective 8D-2 Waste Storage Tank

ML19282B253
Person / Time
Site:	West Valley Demonstration Project
Issue date:	01/17/1979
From:	Crocker H, Kinney W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML19282B251	List: IR 05000201/1978012 ML19282B249
References
50-201-78-12, NUDOCS 7903120048
Download: ML19282B253 (6)

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U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT Region I Report No. 50-201/78-12__

Docket No. 50-201 License No. CSF-1 Priority

Category RP Licensee:

Nuclear Fuel Services, Incorporated C000 Executive Boulevard Rockville, Maryland 20352 Facility Name:

West Valley Reprocessing Plant Inspection at:

West Valley, New York

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Inspection conducted: December 12-13, 1978 Inspectors:

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W. W. Kinney, Project' Inspector

'date signed

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j date signed date signed Approved by m

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H.' WTCrockerMhief, Fuel Facility

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dM signed Projects Section, FF&MS Branch Inspection Summary:

Inspection on December 12-13,1978 (Report No. 50-201/78-12)

Areas Inspected:

Reactive, unannounced inspection by a region-based inspector of the circumstances and licensee action concerning the discovery of a defect in the pan that sits under and holds the in-service 8D-2 waste storaga tank.

The inspection involved 13 inspector-hours on site by one NRC region-based inspector.

Results:

No items of noncompliance or deviations were identified.

03 120oyg Region I Fom 12 (Rev. April 77)

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DETAll.S 1.

Persons Contacted

• W. A. Oldham, General Manager / Plant Manager

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J. P. Duckworth, Technical Service Manager

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A. C. Pierce, Operations Manager i

C. E. Seitter, Quality Assurance Supervisor

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Scope of Inspection This was a special reactive inspection of the circumtances sur-

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rounding the discovery of a defect in the 8D-2 pan that sits under and holds the in-service 8D-2 waste storage tank.

3.

Dij.overy of Defect

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On November 15, 1978, the licensee initiated the work to confirm the operation of the pan liquid level detection system by adding water to the 8D-2 pan and verifying the instrument response.

This was being done in accordance with the October 12, 1978, letter from

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the licensee to the Fuel Reprocessing and Recycle Branch of the

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Division of Fuel Cycle and Material Safety of the Nuclear Regulatory Commission.

The licensee added measured quantities of water into the pan in increments until 3000 gallons of water had been added to the pan.

This amount of water should have caused the pan liquid level in-dicating instrument, 8LI-5, to start showing a liquid level in the

pan.

The licensee installed a temporary probe down the 2 inch i

sample tube and this was connected to a manometer.

This manometer

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indicated a 4.1 inch level of water in the pan.

The licensee continued to add water incrementally to the pan.

During these additions, time was required for an equilibriun level to be reached, because the water had to seep into the pea gravel and perlite blocks which supported the waste tank 15 inches above 1he pan.

There are semi-circular holes in the bottom of the re-taining ring used to hold this pea gravel and perlite blocks in place.

According to the licensee's drawings, these 1 1/2 inch semi-circular holes were cut in the bottom of the retaining ring at the pan level after the tank was stress relieved.

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The licensee continued to add increments of water until a total of 26,500 gallons of water had been added on tiovember 29,1978, and the liquid level in the pan from the manometer reading was 16.9 inches.

The regular pan liquid level indicating instrument, 8LI-5, never responded.

On November 30,1978, at 0100, while taking the routine shift readings, the operator observed a reading of 6.8 inches of water on the vault liquid level indicating instrument, 8LI-15.

This level remained stable throughout the night.

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instrument was examined by the instrument technician at 0835 and was verified to be functioning properly.

The water in the pan was sampled on November 30, 1978, and the result was 2 x 10-6 uCi/ml.

The water in the pan was pumped to 8D-2 tank (about 1500 gallons) and to Lagoon 1.

The vault reading was zero when the pan level reading was about 10 inches.

The licensee then decided to do the following:

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Esta lish a pan level indicating probe which had a definite known distance from the bottom of the probe to the bottnm of

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the pan.

b.

Determine if water travelled from the vault to the pan with the pan liquid level at its pump heel.

c.

Retest the 8LI-5, the original pan level indicating instru-ment.

d.

Check the fabrication of the vault jet assembly.

On December 1,1978, the licensee installed a welded 1/4 inch stainless steel dip tube on the pan pump.

The licensee measured the distance from the bottom of the dip tube to the pump niche flange to be 38 feet and 6 inches.

The licensee also measured the distance from the bottom of the pan to the pump aiche flange to be 38 feet and 8 3/8 inches.

Therefore, the bottom of the new probe is 2 and 3/8 inches from the bottom of the pan.

On Decemhtc 4,1978, water was added to the 8D-2 vault via the LI-15 instrument line to determine if water travelled from the vault to the pan.

The pan level increased from 2.45 inches to 5.20 inches during this test in which 1,250 gallons of water were added to the vault.

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The licensee ran water down the 8LI-5 probe line, and the level of the water in the pan increased.

The licensee then reconnected the probe line to the instrument, and the instrument again gave a zero reading.

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On December 6, 1978, the licensee inserted a copper tubing down the 8LI-15 probe, the probe for the vault liquid level indicating

instrument.

When the bottom of the vault was detected, the licensee connected a manometer to the tubing.

The manometer gave a reading i

of 16.4 inches of water The 8LI-15 probe had given a reading of

about 3.2 inches of water. The 8LI-15 probe was shown to be about 13 inches above the vault gravel.

On December 7,1978, the licensee removed the 8D-2 vault (jet) and level probe assembly from the vault and measured it.

Measurements confirmed that the assembly is 12 inches shorter than the length shown on the construction prints.

On December 7,1978, the 8D-2 pan liquid was again sampled, and the sample contained 6.6 x 10-7 uCi/ml B.

4.

Analysis of Situation

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The licensee has definitely shown that the pan will not contain water. The licensee has shown that the defect is between 0 and 3 inches from the bottom of the pan.

The licensee has shown that the original pan liquid level indicating instrument was not working, and this 3LI-5 instrument would not

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have detected a leak from the 8D-2 tank, i

The licensee has shown that the 8D-2 valut eductor and level probe

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assembly is about 12 inches shorter than tias shown on the construc-tion prints. Therefore, there had to be about 13 inches of water above the vault gravel before the water reached the 8LI-15 probe.

Therefore, if a leak from the 8D-2 tank had occurred and if the information given before were not known, the first indication of a liquid level in either the pan or the vault would have been a level indication in the vault.

The level of liquid in the 8D-2 tank would also have shown a decrease.

This information would probably have been interpreted as a leak in the vault with ground water

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getting inside the vault, since the pan probe would have shown no level of liquid in the pan.

There is no way to sample the vault liquid.

After the level got high enough in the vault, the licensee would have jetted the water from.the vault into the pan.

Again no indication of liquid level in the pan would have been shown.

The licensee would have then probably sampled the liquid to the 8D-2

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tank or to Lagoon #1.

At this time, the fact that a leak was

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present would have been discovered. The licensee probably would

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not have discovered the leak in the 8D-2 tank until about 23,000 to 25,000 gallons of waste had leaked from the tank.

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The licensee also attempted to sample any liquid in the pan every

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quarter.

The presence of liquid waste in the pan might well have

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been discovered from this sample before the vault liquid level in-dicator 8LI-15 showed a reading.

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From'the above discussion, it is apparent that the 8D-2 pan and

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vault have now been much better equipped to allow early discovery of a leak in the 8D-2 tank than was present before the attempt was made to confirm the operation of the pan liquid level detection system.

It is also apparent that the pan cannot now be used to hold waste for pumping back into the 8D-2 tank with the waste not reaching the vault.

Now the barriers are the tank, the vault and the silty till.

The licensee can continue to pump any waste from the pan and vault back into the tank, while taking the required measure to transfer the waste from the 8D-2 tank to the spare tank, 8D-1.

5.

Tests of 8D-1 Pan and Vault Liquid Level Indication Systems

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The licensee inserted a copper tube into the vault level indicating probe, 8LI-14, since it was anticipated that the as-installed 8LI-14 probe would be 12 inches short as was the 8LI-15 probe into the 8D-1 pan sample tube to assure that the pan level reading would be

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from the bottom of the pad.

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There was water in the 80-1 vault and the 8D-1 pan before the test was initiated.

These levels were read.

Then water was jetted from the vault to the pan. There was no unexpected change in the levels after the jetting was completed.

The licensee then added water to the 80-1 vault via the vault instrument tube.

Ti.e pan level reading stayed the same.

The vault level increased from 12.5 inches to

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58.4 inches upon the addition of 3000 gallons to the vault. This level was held for several hours and it renained stable.

The water in the vault was jetted to the pan.

The vault level decreased from 58.4 inches to 12.05 inches during the jetting.

The pan level increased from 8.84 inches to 17.19 inches during the jetting.

These levels remained stable for at least 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />.

The 80-1 pan

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is apparently sound at this time.

6.

Further Licensee Planned Actions The licensee plans to take the following actions.

Examine the retaining ring used to hold the pea gravel and a.

perlite blocks in place in the 8D-1 pan.

An engineer will i

physically enter the vault to do this.

Special attention will

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be paid to the semi-circular holes at the bottom of the ring.

b.

Examine records to determine if the pans were tested for

holding liquids at the time of construction.

I Investigate availability of equipment to remotely view the 8D-

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2 pan, retaining ring, and vault.

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Probably extend the 80-2 and 8D-1 vault eductor and level

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probe assembly to the lengths shown in the drawings.

Investigate methods to upgrade leak detection systems.

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f.

Investigate moisture removal systems for removing moisture

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from the 8D-2 vault.

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7.

Exit Interview

The inspector met with the licensee representative (denoted in Paragraph 1) at the conclusion of the inspection on December 13, 1978.

The inspector stated that there were no apparent items of noncompliance concerning the situation of the defect in the 8D-2 pan and the licensee's actions.

The inspector reinforced the re-quest that a report concerning the defect and licensee action be made to the NRC by the licensee.

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