ML20082L987

NPDES Noncompliance Notification:On 910707 & 19,electrical Storm Caused Loss of Power to Bedminster Water Processing Facility & Tripped Chillers.On 910721,discharge Temp Exceeded Permitted Limits.Permit Limits Changed

ML20082L987
Person / Time
Site:	Limerick
Issue date:	08/28/1991
From:	Doering J PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Noll P NESHAMINY, PA
References
NUDOCS 9109040498
Download: ML20082L987 (4)

Text

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d e PHILADELPHI A ELECTRIC COMPANY LIMEHICK GENEH ATING ST ATION P.O.DOX A S AN ATOG A. PENNSY LV ANI A 19464 (215) 327 1200 t ut. ,000

' . f.S ,' ".'.".h .'." ' August 28, 1991 Mr. Peter G. Noll Department of Health Nenhaminy Manor Center Doylestown, PA 18901 Subjects Noncompliance with NPDES Permit Bradshaw Reservoir NPDES Permit No. PA-0052221

Dear Mr. Noll:

DESCHIPTION OF NONCOMPLIANCES The following noncompliances with NPDES Permit No. PA-0052221, Bradshaw Reservoir, occurred during the month of July, 1991:

o On July 7, an electrical storm caused a loss of power to the Bedminster Water Processing Facility and a subsequent trip of the

'A' chiller. Discharge temperature exceeded the permitted maximum limitation of 74 degrees P between 1400 and 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> with a maximum temperature of 75.7 degrees P. Temperature was restored within permitted limits upon restart of the chiller.

o On July 19, an electrical storm caused a loss of power to the Bedminster Water Processing Facility and subsequent chiller trips. Discharge temperature exceeded permitted limitations between 1300 and 1500 hours0.0174 days <br />0.417 hours <br />0.00248 weeks <br />5.7075e-4 months <br /> with a maximum temperature of 74.1 degrees P. Temperature was restored within permitted limits upon restart of the chillers.

o On July 21, between 1200 and 2300 hours0.0266 days <br />0.639 hours <br />0.0038 weeks <br />8.7515e-4 months <br />, due to extreme ambient conditions, the discharge temperature exceeded the permitted limits. The maximum temperature recorded was 75.5 degrees P.

Due to the inability to operate the Bradshaw pumps in the variable flow mode of operation, maintaining the DRBC minimum flow requirement of 27 cfs was unachievable. Operation of one Bradshaw pump in full flow is insufficient to maintain 27 cfs.

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Operation of two Bradshaw pumps in full flow results in a discharge rate of approximately 46 cfs. Discharge flow was maintained at the lowest available limit of approximately 46 cfs with two Bradshaw pumps operating. All three Bedminster chillers and three cooling towers were operating. As ambient conditions '

improved, the discharge temperature was restored within_ permitted limits.

9109040498 910828 PDR ADOCK 05000352 00 o PDR l3 'dboao ip

Page 2 o On July 23, between 1200 and 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br />, due to extreme ambient conditions, the discharge temperature exceeded the permitted limits. The maximum temperature recorded was 75.7 degrees F.

Discharge flow was maintained at the lowest available flow rate of approximately 46 cfs with two Bradshaw pumps operating. All three Bedminster chillers and three cooling towers were operating. At approximately 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br />, an electrical storm caused a loss of power to the Bradshaw facility, and all threc  ;

pumps tripped. Attempts to restart and operate the pumps in the l variable flow mode were unsuccessful. At approximately 2200 l hours, two pumps were started operating at full flow (46 cfs).

Ambient conditions had improved, therefore the discharge temperature was restored within permitted limits.

o On July 25, between 0300 and 0500 hours0.00579 days <br />0.139 hours <br />8.267196e-4 weeks <br />1.9025e-4 months <br />, due to an inability to remotely shutdown the Bradshaw pumps, the discharge temperature exceeded permitted limitations. The maximum temperature recorded was 74.5 degrees F. All three Bedminster chillers, all three cooling towers and three Bradshaw pumps were in operation. Due to ambient conditions, the Bedminster facility could not maintain .

discharge temperature within permitted limits with three Bradshaw I pumps running (discharge flow of approximately 61 cfs). One of  :

, the Bradshaw pumps was manually shut down at approximately 0500  !

hours to achieve compliance with the discharge temperature limit.

l o On July 26, an electrical storm caused a loss of power to the j Bradshaw pumps and the Bedminster. chillers. Discharge

temperature exceeded permitted limitations between 1800 and 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br /> with a maximum temperature of 74.4 degrees F. Upon restart of the pumps and chillers, discharge temperature was restored within permitted limits.

j Notifications of these noncompliances were made to either Mr. Peter Noll or Mr. David Noll of the Department of Health in accordance with i NPDES permit requirements. In each instance, the requirement for l submittal of a 5-day report was waived by the Department and, j therefore, the required written report is being submitted in this j letter which is being included in the monthly submittal of the i Discharge Monitoring Report.

! CAUSES OF THE NONCOMPLIANCE l

l The causes of these six-instances of noncompliance were_ varied, I including electrical storms, extreme ambient-conditions,-the-j inability to remotely control the Bradshaw facility, and the i

inability to operate the Bradshaw pumps in the variable flow mode of operation. The Bradshaw and Bedminster facilitics_are new and this has been the first full cooling season of operation. Minor design

problems and equipment malfunctions and failures have hampered i operation of these two facilities. During startup and operation of facilities such as these, certain-system control problems-and l equipment malfunctions or failures are expected. During discussions between PA DER'and Delaware River Basin-Commission (DRBC)

authorities, and Limerick Generating Station personnel, it was L

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P Page 3 determined that, in order to minimize any potential for environmental impact during an operating transient, discharge flow should be maintained above the DRBC rainimum flow requirement of 27 cfs in preference to attempting to maintain the discharge below the maximum temperature limits. Due to the inability to operate the Bradshaw pumps in the variable flow mode of operation, maintaining this minimum flow rate was unachievable. However, the lowest flow rate achievable was maintained. Operation of one Bradshaw pump in full '

flow is insufficient to maintain 27 cfs. Operation of two Bradchaw pumps in full flow results in a discharge rate of approximately 46 cfs.

PRT: VENT 10N OF PUTURE OCCURRENCES Permit requirements for the 1991 cooling season essentially ended on August 1, 1991, when the maximum discharge temperature limit changed from 74 degrees P to 87 degrees F. This removes the need for cooling of the discharge water thereby minimizing the possibility for exceeding permitted temperature limitations until the 1992 cooling season. These facilities will be modified / repaired prior to the 1992 cooling season, which begins on February 15, 1992, to improve remote operation of the Bradshaw and Bedminster facilities from the Limerick Generating Station Main Control Room. The Bradshaw pumps are designed to operate ir. the variable flow mode of operation, however repairs requiring a facility shutdown are required. Operation of the Bradshaw pumps in the variable flow mode w1]l be possible after maintenance, enabling operators to adapt more easily to changing or extreme ambient conditions. If the remote operating capability and the Bradshaw pump variable speed capability had been operating properly during the past cooling season, the violations wn Jujy 21, 23, and 25, 1991 could have been avoided. The remote operation capability will additionally minimize the impact of pump trips due to 1 electrical storms. Additionally, a revised facility operating plan wl:1 be issued prior to the 1992 cooling r3ason. This revision will provide an operating strategy for abnormal conditions such as those l that occurred in 1991. These enhancements to facility operation will l serve to minimize the possibility of future noncompliances.

l I

Sincarely, l_ fq L&d h +c' 10' J. Doering, Jr.

Plant Manager DCS:cah

Page 4 cc U.S. Nuclear Regulatory Commission Document' Co;. trol - Dcsk .

Docket Nos. 50-352/50-353 Washington, D.C. 20555 T. T. Martin Administrator, Region I, USNRC Docket Nos. 50-352/50-353 T. J. Kenny USNRC Senior Resident Inspector, LGS Docket Nos. 50-352/30-353 Program Management Section (3WM52)

Permits Enforcement Branch Water Management Division Environmental Protection Agency -

Water Permits Section Region III 841 Chestnut Building Philadelphia, PA 19107 l

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