[Federal Register Volume 59, Number 201 (Wednesday, October 19, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-25857]


[[Page Unknown]]

[Federal Register: October 19, 1994]


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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-302]

 

In the Matter of: Florida Power Corporation Crystal River Nuclear 
Generating Plant Unit 3; Exemption

I

    Florida Power Corporation (the licensee) is the holder of Facility 
Operating License No. DPR-72, which authorizes operation of the Crystal 
River Nuclear Generating Plant Unit 3. The license provides, among 
other things, that the licensee is subject to all rules, regulations, 
and orders of the Commission now or hereafter in effect.
    The facility is of a pressurized water reactor type and is located 
in Citrus County, Florida.

II

    Title 10 Code of Federal Regulations Part 50 (10 CFR Part 50), 
Appendix A, ``General Design Criteria for Nuclear Power Plants,'' 
Criterion 3, ``Fire protection,'' specifies that ``Structures, systems, 
and components important to safety shall be designed and located to 
minimize, consistent with other safety requirements, the probability 
and effect of fires and explosions.''
    10 CFR Part 50, Appendix R, sets forth fire protection features 
required to satisfy general design Criterion 3 of the Commission's 
regulations. Pursuant to 10 CFR Part 50, Appendix R, Section III. O, 
``Oil collection system for reactor coolant pump,'' the reactor coolant 
pump (RCP) shall be equipped with an oil collection system which ``* * 
* shall be capable of collecting lube oil from all potential 
pressurized and unpressurized leakage sites in the reactor coolant pump 
lube oil systems.''
    The licensee proposed to replace the existing RCP motors with a new 
motor and implement a re-designed RCP lube oil system. As a result of 
physical interferences and other design difficulties, four specific 
sites in the RCP motor lube oil system could not accommodate an oil 
collection systems for collecting potential oil leakage. The four 
potential leakage sites are: the anti-reverse device (ARD) vents, upper 
oil supply lines from the lift pump to the ARD, lower motor leak 
detection system piping, and lower guide bearing thermocouple wells.
    An exemption from 10 CFR Part 50, Appendix R, Section III. O, is 
required to permit the four specific sites in the RCP lube oil systems 
not to be equipped with an oil collection system, and thus, exclude 
them from leakage protection.
    By letter dated June 7, 1993, as supplemented March 28, 1994, the 
licensee submitted its exemption request for this purpose.

III

    Pursuant to 10 CFR 50.12, the Commission may, upon application by 
any interested person or upon its own initiative, grant exemptions from 
the requirements of 10 CFR part 50 when (1) the exemptions are 
authorized by law, will not present an undue risk to public health or 
safety, and are consistent with the common defense and security; and 
(2) when special circumstances are present. Special circumstances are 
present whenever, according to 10 CFR 50.12(a)(2)(ii), ``Application of 
the regulation in the particular circumstances would not serve the 
underlying purpose of the rule or is not necessary to achieve the 
underlying purpose of the rule * * *''.
    The underlying purpose of 10 CFR 50, Appendix R, Section III. O, is 
to establish an oil collection system such that lube oil leakage from 
potential pressurized and unpressurized leakage sites in the RCP lube 
oil systems will not lead to fire during normal or design basis 
accident conditions and that there is reasonable assurance that the 
system will withstand the Safe Shutdown Earthquake (SSE).
    The licensee's proposed RCP motor lube oil system could not 
accommodate an oil collection system for collecting potential oil 
leakage from four specific sites. The staff evaluation of these sites 
is as follows.
    The RCP motor lube oil system, with its pumps and associated 
piping, supply oil to several parts of the RCP. The existing RCP lube 
oil system includes a high pressure and an induced flow system. The 
high pressure system consists of two independent pumps, and associated 
piping, and supplies oil, among other components, to the ARD. The 
induced flow system is driven by the rotation of the RCP motor and 
provides lube oil to the thrust bearings, guide bearings, and to the 
ARD.
    In the new design, the ARD vents located at the top of each RCP 
motor would be equipped with demisters. According to the equipment 
vendor, the ARD vent lines only contain oil mist or foam during 
startup, shutdown, and normal operation. The demisters are equipped 
with a filter to prevent lube oil mist from escaping to the atmosphere. 
Two upper lube oil supply lines provide oil to the ARD from the low 
pressure lube oil system lift pump during startup and shutdown of the 
RCP motor. During normal operation, oil is provided to the ARD by the 
induced flow system.
    The ARD vents are not part of a pressurized system. Therefore, 
spray shield protection for mechanical connections is not provided. If 
leakage were to occur during normal plant operations from the ARD 
demisters or from the mechanical connections, the oil would run down 
the side of the torque drum and bearing housing, be collected by a one-
inch lip on the bottom of the upper RCP motor bearing housing, and then 
be channeled to the oil collection drain pan for the upper lube oil 
cooler. The two upper lube oil supply lines are part of a pressurized 
system and, therefore, lube oil spray from a leak at a mechanical 
connection may not be fully captured by this lip and could potentially 
run down the RCP motor onto hot Reactor Coolant System (RCS) surfaces.
    The lower RCP motor leak detection system provides detection of 
water leakage from the RCP motor heat exchanger. Consequently, this 
system normally contains cooling water. However, oil may enter into the 
cooling water either from overfilling the lube oil reservoir or from 
leakage at the lower RCP motor bearing. The mixture of water/oil could 
potentially leak at the threaded connections of the leak detection 
system piping and run off onto hot RCS surfaces. It is not expected 
that this oil/water mixture would represent a fire hazard under these 
conditions. These lines are not part of a pressurized system and are 
not provided spray protection for this potential leakage site.
    The lower guide bearing and oil temperature thermocouples are 
located near the lower RCP motor bearing housing. Each of these 
instruments has two threaded connections. One of these connections is 
at the RCP motor lower bearing oil reservoir and the other is at the 
outer end of the thermocouple pipe where the thermocouple is inserted 
into the pipe. These thermocouple connections are located in a non-
pressurized portion of the lube oil system and are not provided with 
spray shields. The innermost connections are located directly over the 
RCP motor lower oil drain pan and it is expected that leakage from 
these connections would be captured by the lower drain pan.
    The new oil lubricating system would contain approximately 200 
gallons of oil and would eliminate one of the two lift pumps and its 
components, which should result in a decrease in the number of 
potential leakage sites. Of the four potential leakage sites, ARD vents 
and lower RCP motor leak detection system piping do not contain oil 
under routine operating conditions. The upper oil supply lines from the 
lift pump to the ARD are pressurized only during a brief period of 
motor startups and shutdowns. The lower guide bearing thermocouple 
wells are passive in nature. If leakage were to occur during normal 
plant operations, the oil would channel to the drain pan. Any lobe oil 
leak which may not have been fully captured could potentially run down 
the RCP motor onto hot Reactor Coolant System surfaces. However, the 
flammability characteristics of the oil, flashpoint of 452 deg.F, and 
an auto ignition temperature of 500 deg.F-700 deg.F, that would be used 
in the lube oil system, reduce the likelihood that the oil will readily 
ignite upon coming in contact with hot RCS piping surfaces. 
Additionally, if the oil leak became ignited, the fire would be 
localized in the area of the leakage and detected by the thermal fire 
detectors.
    Fire protection features for the RCP motors include three 
temperature heat detectors with 190 deg.F setpoints located over each 
RCP. Any localized fire in the area would result in an alarm function 
in both the reactor building and annunciate in the main control room. 
Additional indications of potential RCP fire are provided by control 
room alarms on low level oil, low oil pressure or high vibrations. It 
is expected that the control room operators would evaluate these alarms 
associated with the RCP and its lube oil system and initiate fire 
brigade entry into the reactor building to investigate and fight the 
fire. The reactor building is equipped with an internal firefighting 
standpipe hose station system and fire extinguishers are appropriately 
distributed throughout the structure. RCP firefighting would be 
accomplished by using either portable fire extinguishers or water from 
a hose stream or a combination of both. Access to the four RCPs for 
firefighting can be accomplished by making entry into the ``D'' rings.
    The existing Crystal River Unit 3 RCP motor lube oil system in a 
nonseismic system. The new RCP lube oil system and lube oil collection 
systems would be seismically qualified to withstand an SSE. Therefore, 
if an SSE were to occur, the system is not expected to fail.
    Based on the design features of the new RCP motors and associated 
lube oil collection systems, there is reasonable assurance that the RCP 
lube oil system will not lead to fire during normal and design basis 
accident conditions or present a major fire hazard during a seismic 
event. In addition, based on the present level of fire protection 
provided for the RCPs and the fact that the plant has a trained fire 
brigade, if a fire were to occur in the area of RCP lube oil system ARD 
vents, upper oil supply lines from the lift pump to the ARD, lower 
motor leak detection system piping, and lower guide bearing 
thermocouple wells, there is reasonable assurance that the fire 
condition will be detected and mitigated.

IV

    For the foregoing reasons, the NRC staff has concluded that the 
licensee's proposed implementation of the RCP lube oil system with the 
four potential leakage sites (the ARD vents, upper oil supply lines 
from the lift pump to the ARD, lower motor leak detection system 
piping, and lower guide bearing thermocouple wells not equipped with an 
oil collection system) will not present an undue risk to public health 
and safety and is consistent with the common defense and security. The 
NRC staff has determined that there are special circumstances present, 
as specified in 10 CFR 50.12(a)(2), such that application of 10 CFR 
Part 50, Appendix R, Section III. 0, as it relates to the oil 
collection at four specific sites in the RCP, is not necessary in order 
to achieve the underlying purpose of this regulation.
    Accordingly, the Commission has determined that, pursuant to 10 CFR 
50.12(a), an exemption is authorized by law, will not endanger life or 
property or common defense and security, and is otherwise in the public 
interest. Therefore, the Commission hereby grants Florida Power 
Corporation an exemption from those requirements of 10 CFR Part 50, 
Appendix R, Section III. 0, relating to oil collection in the RCP. This 
exemption is applicable only to the four potential leakage sites in the 
RCP lube oil system: the ARD vents, upper oil supply lines from the 
lift pump to the ARD, lower motor leak detection system piping, and 
lower guide bearing thermocouple wells.
    Pursuant to 10 CFR 51.32, the Commission has determined that the 
granting of this exemption will not result in any significant adverse 
environmental impact (59 FR 48338).

    Dated at Rockville, Maryland, this 7th day of October 1994.

For the Nuclear Regulatory Commission.
Steven A. Varga,
Director, Division of Reactor Projects--I/II, Office of Nuclear Reactor 
Regulation.
[FR Doc. 94-25857 Filed 10-18-94; 8:45 am]
BILLING CODE 7590-01-M