[Federal Register Volume 65, Number 68 (Friday, April 7, 2000)]
[Notices]
[Pages 18379-18380]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8631]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-255]
Consumers Energy Company (Palisades Plant); Exemption
I
Consumers Energy Company (the licensee) is the holder of Facility
Operating License No. DPR-20, which authorizes operation of the
Palisades Plant. The facility consists of a pressurized-water reactor
at the licensee's site located in Van Buren County, Michigan. The
license provides that the licensee is subject to all rules,
regulations, and orders of the U.S. Nuclear Regulatory Commission (the
Commission) now or hereafter in effect.
II
The Code of Federal Regulations, 10 CFR part 50, appendix R, ``Fire
Protection Program For Nuclear Power Facilities Operating Prior To
January 1, 1979,'' Section III.O, ``Oil Collection System for Reactor
Coolant Pump,'' requires that primary coolant pumps be equipped with
oil collection systems (if the containment is not inerted during normal
operation) capable of collecting lube oil from potential leakage sites
in the primary coolant pump lube oil systems. Section III.O includes a
specific requirement regarding the capacity of the lube oil collection
container: ``Leakage shall be collected and drained to a vented closed
container that can hold the entire lube oil system inventory.'' The
underlying purpose of Section III.O requirements is to provide
reasonable assurance that leakage from primary coolant pump lube oil
systems will not lead to a fire that could damage safety-related
equipment during normal or design-basis accident conditions.
Pursuant to 10 CFR 50.12(a), the Commission may grant exemptions
from requirements of 10 CFR Part 50 that are authorized by law, will
not present an undue risk to the public health and safety, and are
consistent with the common defense and security, provided that special
circumstances are present. Pursuant to 10 CFR 50.12(a)(2)(ii), special
circumstances are present whenever ``application of the regulation in
the particular circumstances * * * is not necessary to achieve the
underlying purpose of the rule.''
III
The Palisades Plant consists of a two-loop, pressurized water
reactor with two primary coolant pumps returning flow from each of the
two steam generators to the reactor core. Each of the four primary
coolant pumps is powered by a vertical shaft motor with upper and lower
bearing assemblies. Each bearing assembly has its own separate
lubrication system consisting of an oil reservoir and associated
piping. The upper reservoir for each pump motor could contain up to 87
gallons of lube oil, of which 76 gallons would be in the oil reservoir
and 11 gallons in the associated piping systems (including lift and
backstop pumps and their respective oil coolers). The nominal volume of
the lower reservoir is 18 gallons, with no significant volume in the
associated piping. Thus, the total inventory of lube oil that each
primary coolant pump motor could contain is 105 gallons.
Each of the four primary coolant pump motors has a separate closed
and vented oil collection tank to collect oil leakage. Each of the oil
collection tanks for the motors of primary coolant pumps P-50A, P-50B,
and P-50C has a usable capacity of 79 gallons, which is insufficient
(by 26 gallons) to contain the entire lube oil inventory of the pump
motor. There is reasonable assurance that the oil collection systems
would withstand a safe shutdown earthquake.
Operating procedures and practices at the Palisades Plant are such
that oil spillage due to overflowing an existing collection tank is
unlikely. The operating levels in the upper and lower lubricating oil
reservoirs must be maintained above a minimum level to keep the
bearings properly lubricated during motor operation. The operating
level for the upper reservoir is about 20 gallons and the operating
level for the lower reservoir is about 5 gallons. Any significant
leakage or change in leakage trends would be identified through regular
monitoring by control room operators and by oil level alarms. The
operators would shut down a primary coolant pump if oil leakage caused
either reservoir to reach an operating level low enough to threaten
motor bearing damage, or if the lubricating oil level dropped at a rate
that would cause concern about safe pump operation. Stopping the pump
(and its oil lift pump) would depressurize the leaking lubricating oil
system. The cause of the oil leakage would be investigated and
repaired, and the collection tank would be pumped out before returning
the pump to operation. Stopping a primary coolant pump during reactor
operation would result in an immediate reactor shutdown.
In the unlikely event that operators allowed leakage in a primary
coolant pump motor's upper oil system to drain the entire system
without taking action to stop the pump, approximately 8 gallons of oil
could overflow the oil collection tank onto the floor in containment.
Approximately 26 gallons could overflow onto the floor in the less
likely event that both the upper and lower oil systems were to develop
gross leakage simultaneously with no operator action.
Lubricating oil that might overflow an oil collection tank would
flow down to lower floor elevations and eventually into the containment
sump. The motor oil has a flash point of over 400 deg.F and the
containment atmosphere is nominally 80 deg.F to 100 deg.F when the
primary coolant pumps are in operation. The oil would not come into
contact with any hot pipes, hot equipment
[[Page 18380]]
surfaces, or electrical ignition sources in the tank areas or in the
flow paths to the sump. Thus, the oil would not become a fire hazard
and would drain to a safe location.
By its response to Question 6.2 of Generic Letter 86-10,
``Implementation of Fire Protection Requirements,'' the NRC staff has
previously addressed the use of splash shields and the containment sump
for the collection tank volume. The NRC staff concluded that, although
an exemption would be required, it would be acceptable if the collected
overflow of lube oil drained to the sump, and there were no sources of
ignition in the area. The NRC staff finds that the exemption requested
for the Palisades Plant meets the guidelines for an acceptable
exemption as addressed by the NRC staff in Generic Letter 86-10.
Accordingly, the usable capacity of the existing lube oil
collection tanks for the motors of primary coolant pumps P-50A, P-50B,
and P-50C, in conjunction with the low risk associated with minor
amounts of potential oil overflow to the containment sump, which would
not lead to a fire, satisfies the underlying purpose of Section III.O
of Appendix R to 10 CFR 50.
IV
Pursuant to 10 CFR 50.12(a), the Commission has determined that
special circumstances exist at the Palisades Plant in that application
of the regulation regarding the capacity of lube oil collection
containers is not necessary to achieve the underlying purpose of that
requirement in Appendix R to 10 CFR part 50. The Commission has also
determined that this exemption is authorized by law, will not present
an undue risk to public health and safety, and is consistent with the
common defense and security. Therefore, the Commission hereby grants
the licensee an exemption from the requirements of Section III.O of
Appendix R to 10 CFR Part 50 regarding the specified capacity of lube
oil collection containers. This exemption applies to the lube oil
collection containers for the motors of primary coolant pumps P-50A, P-
50B, and P-50C, based on the facts set forth herein.
Pursuant to 10 CFR 51.32, the Commission has determined that the
granting of this exemption will have no significant impact upon the
quality of the human environment (65 FR 16971).
This exemption is effective upon issuance.
Dated at Rockville, Maryland, this 31st day of March 2000.
For the Nuclear Regulatory Commission.
John A. Zwolinski,
Director, Division of Licensing Project Management, Office of Nuclear
Reactor Regulation.
[FR Doc. 00-8631 Filed 4-6-00; 8:45 am]
BILLING CODE 7590-01-P