ML20248C638

NPDES Noncompliance Notification:On 890718,24 & 0804,total Residual Chlorine Limitation Exceeded.Storage Tank & Containment Dike Repaired & Personnel Counseled

ML20248C638
Person / Time
Site:	Point Beach
Issue date:	09/29/1989
From:	Fay C WISCONSIN ELECTRIC POWER CO.
To:	WISCONSIN, STATE OF
References
VPNPD-89-515, NUDOCS 8910030529
Download: ML20248C638 (3)

Text

_ .- _

I Wisconsin Electnc eaara couesur 231 W MICHIGAN.P O BOX 2046, MILWAUKEE,Wl53201 (414)221-2345 VPNPD-89-515 September 29, 1989 State of Wisconsin DEPARTMENT OF NATURAL RESOURCES WPDES Permit Section Post Office Box 7921 Madison, Wisconsin 53707 Gentlemen:

WPDES PERMIT WI0000957-4 POINT BEACH NUCLEAR PLANT on July 20, July 27, and August 7, 1989, Wisconsin Electric notified the Department that total residual chlorine (TRC) effluent limitation of 0.2 mg/l was exceeded at Point Beach Nuclear Plant (PBNP). The following information is a summary of the data reported:

Estimated Time Date of Incident Above Limit TRC Concentration (minutes) (mg/1)

July 18, 1989 21 0.42 July 24, 1989 23 0.84 August 4, 1989 32 0.73 A temporary chlorination / dechlorination system is in use, and the plant is in the process of testing the recently constructed permanent chlorination / dechlorination system. Activities related to testing the permanent system and provisions which are being made to complete the transition from the temporary to the permanent system have led to exceedances of the TRC limit. 4 These exceedances are not expected to occur after completion and final testing of the permanent chlorination / dechlorination system. Completion and final testing should be done by November 1989.

$EY

-~

8910030529 890929 PDR- ADOCK 05000266

(=t fRQD __ _ _ _ . - __-____________________ _ _

. ~

N I

DNR WPDES Permit Section September 29, 1989 Page 2 Description of Incidents July 18, 1989 A bulk tanker truck was in the process of filling the new sodium hypochlorite storage tank when a leak was observed near the bottom of the tank. This tank had already successfully passed a hydrostatic test with water. At l

1215 the sodium hypochlorite spilled into the concrete i

containment dike area around the storage tank which was I also observed to be leaking. Tank-filling ceased, and plant personnel took immediate action to limit the leak.

The sodium hypochlorite leaking from the east side of the dike was directed to the Unit 1-A circulating water pump suction where dechlorination could be used to remove the TRC from the discharge. The sodium hypochlorite leaking from the west side of the dike wall leaked into the Unit 1-A circulating water pump pit where it was temporarily contained. At 1226 a total residual chlorine (TRC) sample was taken from the Unit 1 discharge and was found to be 0.28 mg/1.

i Dechlorination using the temporary system commenced at 1228 to remove the TRC from the discharge, and at 1231 TRC was no longer detected (<0.01 mg/1) in the discharge. Leakage was minimized from the storage tank by pumping its contents back into the tanker truck. The sodium hypochlorite contained by the dike was pumped into two portable storage tanks. Leakage from the dike stopped at 1630. The storage tank and containment dike have undergone repairs necessary to prevent recurrence of such an incident.

Plant personnel began pumping the sodium hypochlorite trapped in the Unit 1-A circulating water pit to the circulating water pump suction at 1805. Although the new dechlorination system was running, the Unit 1 circulating water discharge indicated a 0.42 mg/l TRC. At 1810 additional dechlorination was provided by the temporary system, and a sample taken immediately thereafter indicated a TRC concentration of <0.01 mg/1. Pumping from the circulating water pit was completed at 1930 hours0.0223 days <br />0.536 hours <br />0.00319 weeks <br />7.34365e-4 months <br />.

July 24, 1989 The Unit 1 circulating water was chlorinated from 0757 to 0820 without dechlorination. A sample taken at 0813 showed a TRC concentration of 0.84 mg/1. Due to the unusual set-up for chlorination and dechlorination with

z .:

4 I' J DNR WPDES Permit'Section September 29, 1989 ,

Page 3 L

both the temporary and permanent systems in place, plant personnel. inadvertently chlorinated Unit 2 while dechlorinating Unit 1. Samples were taken from both outfalls because of this set-up, and chlorination was ceased upon discovery of the 0.84 mg/l TRC concentration in outfall 002.

The TRC concentration in outfall 001 was <0.01 mg/1.

August 4, 1989 Chlorination of the Unit 2 circulating water began at 1030 and was terminated at 1059 after the sample taken from the discharge at outfall 002 indicated a 0.73 mg/l TRC concentration. A sample taken at 1102 indicated a TRC concentration of <0.01 mg/1. During investigation of the incident, it was found that a cross-connect valve connecting'the recently installed sodium bisulfi;.e (dechlorination chemical) addition piping to each unit's circulation water piping was left open. With this valve in the open position, the sodium bisulfite would have preferentially gone to the Unit 1 circulating water because the Unit 1 condenser outlet water boxes were under a higher vacuum than Unit 2. After this investigation, Unit 2 was chlorinated while the dechlorination cross-connect valve was closed. The samples taken during this' chlorination period did not show detectable quantities of TRC.

Personnel involved with the chlorination / dechlorination system have been reminded of the TRC limitations and that these limitations must be maintained throughout the period cf transition from the temporary to the permanent chlorination /

dechlorination system.

Very truly yours, a C. h<f C. . Fay y

Vice President Nuclear Power Copy to DNR Lake Michigan District NRC Document Control Desk NRC Region III

.__ _ - _ _ - -