ML20133F669

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Responds to NRC Re Violations Noted in Insp Repts 50-286/81-05 & 50-286/84-10.Corrective Actions:Vapor Containment Accident Sampling Sys & Plant Vent Accident Sampling Sys Will Be Modified During Upcoming Outages
ML20133F669
Person / Time
Site: Indian Point Entergy icon.png
Issue date: 06/28/1985
From: Josiger W
POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK
To: Martin T
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20133F664 List:
References
IP-MK-1353, NUDOCS 8508080385
Download: ML20133F669 (3)


Text

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- ATTACINENT I Finding 81-05-10: Determination of the representativeness of post Accident Airborne Effluent particulate Sampling.

F;.nding 84-10-Ila The iodine Line Loss Study now going on should evaluate (85-04-15) the effect of _ altered conditions during the course of an accident. These should include: water vapor, variation of chemical form, continuous vs. intermittent flow and others that might be considered appropriate. ,

Study pesults:

The Iodine Line-Ioss Study performed during the 1984 and 1985 operating period has recently been completed. This study was performed on the Vapor Containment Post Accident Sampling System and is considered representative of the losses which could be expected on the plant vent Accident Sampling System since these systems are of a similar design. The study identified two types

of losses, losses due to impingement (particulate) and losses of gaseous iodine.

The losses of particulate Iodine 131 were approximately 89% + 3% and Cesium 137 were 70% + 7% (mean + standard deviation of mean) . This was ,

based upon ten, one week sar'pling periods. This loss rate was essentially consistent for the sampling period.

The losses of gaseous iodine were reduced as sampling time increased.

These losses ranged during the-ten, one week sample periods from 59% to -20%

with a mean value of 33%. An equilibrium developes with gaseous iodine losses which is a function of sample time. This appears to be very predictable.

Tne chemical species were determined several times during the study.

The distribution of the iodine was as listed below. Quantification of particulate size distribution was attempted but did not have conclusive results.

Gaseous Iodine particulate HOI Organic I Il Iodine 131 4% 10t 26% 60%

Iodine 133 14% 36 % 50%

8500080385 850729 PDR ADOCK 05000286 G PDR

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! The above mentioned losses will be addressed as follows:

Losses of particulates:

1. Ileat trace sample lines to preclude water traps.
2. Elimination of ninety degree elbows and installation of gradual bends with a nominal radii of curvature that are five times the radius of the tubing.
3. Increase tubing dir,eter to reduce the deposition velocity.

Losses of gaseous iodine:

1. Develop a compensation curve for gaseous iodine as a function of sample or recirculation time.

Schedule for completion of tasks:

Vapor Containment Accident Sampling System:

Cycle 4/5 outage 1. Increase tubing diameter and add gradual bends on sample line down stream of R-ll and R-12.

2. Install heat trace on sample line down stream of R-Il and R-12,
3. Develop a gaseous iodine compensation curve.

plant Vent Accident Sampling System:

Cycle 4/5 outage 1. Develope a gaseous iodine compensation curve.

Cycle 5/6 outage

  • 1. Increase tubing diameter and add gradual bends on sample lines down stream of R-13.
2. Install heat trace on the sample lines.
  • The installation of these items at this date will not compromise the ability to quantify radioactive releases from this pathway after an accident due to the effluent prefiltration which is utilized. This prefiltration substantially reduces the particulates released, thus gaseous iodine species l would be the predominant specie being released during an accident.

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