PNO-II-88-011, on 880206,slight Positive Pressure Created in Primary Drain Tank Due to Large Vol of Water & Overhead Gas Compressor Inoperable,Causing Gaseous Leak in Auxiliary Bldg.Cause Not Stated

From kanterella
Jump to navigation Jump to search
PNO-II-88-011:on 880206,slight Positive Pressure Created in Primary Drain Tank Due to Large Vol of Water & Overhead Gas Compressor Inoperable,Causing Gaseous Leak in Auxiliary Bldg.Cause Not Stated
ML20149G379
Person / Time
Site: Surry Dominion icon.png
Issue date: 02/08/1988
From: Cantrell F
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
References
PNO-II-88-011, PNO-II-88-11, NUDOCS 8802180245
Download: ML20149G379 (1)


teoruary o, noo i

PREL1MINARY NOTIFfCATION OF EVENT OR UNUSUAL OCCURRENCE PNO-II-88-11

-g This preliminary notification constitutes EARLY notice of events of P05M7e'7er t

, public interest significance. The information is as initially received without verifi-cation or evaluation, and is basically all that is known by the Region 11 staff On this date.

FACILITY: Virginia Electric and Power Company Licensee Emergency Classification:

Surry Unit 1 Notification of Unusual Event Docket No. 50-280 Alert Surry, Virginia Site Area Emergency General Emergency X Not Applicable

SUBJECT:

GASE0US RELEASE On February 6,1988, Unit I had reduced power to 70% in order to perform turbine valve testing. In anticipation of returning to power, the Reactor Coolant System was being diluted which required diverting letdown flow from the Volume Control Tank to the Primary Drain Tank (PDT). Due to the large volume of water and both overhead gas compressors (associated with the PDT) nct in operation, a slight positive pressure was created in the PDT. This caused a small gaseous leak (exact location presently unknown) in the auxiliary building.

The leakage from thc auxiliary building caused the auxiliary building ventellation vent particulate air monitor to reach the alert (not related to emergency classification) level but not the alarm level. The leakage was picked up by the auxiliary building ventilation system and exhausted via the plant vent stack. The licensee calculated a release of 4.87 Ci noble gas (3.73 Ci of Xe-133, 0.97 Ci of Xe-135, and 0.16 Ci of Kr-85). Iodine concen-trations measured at the stack were 1E-12 uti/cc I-131 and 8.7 E-13 uCi/cc I-133. The licensee calculated that the release was 8.8% of technical specification limit and that the offsite dose was less than 0.01 mrer/hr for a one hour release.

Forty individuals were found to have short-lived nob 1? gas daughters (Rb-88) contamination of clothing when exiting the auxiliary building. This contamination decayed away, with most personnel being released in 20 minutes and all released in 50-55 minutes.

The Comonwealth of Virginia was infurmed.

The NRC received initial notification (information only) of this event from the licensee to the duty officer about 10:37 p.m. (EST) on February 6, 1988.

This information is current as of 11:00 a.m. (EST) en February 8.

CONTACT: F. S. Cantrell - 242-5534 DISTRIBUTION H. Street MNBB Phillips E/W Willste Regions Chairman Zech XE65 NRR DTA NMSS Region I 1'33' Comm. Roberts ARM OI Region !!

Com. Bernthal ED0 Region!!I--*g,h Com. Carr Comm. Rogers PA OGC Air Rights Region IV "2) N SECY SLITP Region V - gT[O OGC-H CA FAX TO: Nicholson Lane MAIL TO: ,

GPA INP0 -M RES OCS (Original) M l ACRS PDR NSAC LICENSEE p g i DOT (Trans. only)

((e RESIDENT INSPECTOR M M t g '

'HOS. OPERATIONS OFFICER k 8802180245 880208 ***************"**"********"*"******""******

\

-I 8-011 DCD