Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
SSINS No.: 6820
Accessions No.:
8002280677
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF INSPECTION AND ENFORCEMENT
WASHINGTON, D.C. 20555
May 6, 1980
IE Bulletin No. 80-10
CONTAMINATION OF NONRADIOACTIVE SYSTEM AND RESULTING POTENTIAL FOR
UNMONITORED, UNCONTROLLED RELEASE OF RADIOACTIVITY TO ENVIRONMENT
Description of Circumstance
At the Brunswick Nuclear Facility, the auxiliary boiler was operated for an
extended period of time with radioactively contaminated water in the boiler
at levels up to 2 x 10 -2 micro curies per milliliter. A tube leak in the
firebox of the oil fired auxiliary boiler resulted in an unmonitored,
uncontrolled release of radioactivity to the environment.
The initial contaminating event was caused by the use of a temporary heating
hose from the auxiliary boiler to a radioactive waste evaporator concentrate
tank. Upon cooling and condensation of the steam in the temporary hose,
contaminated water siphoned from the concentrate tank back to the auxiliary
boiler. Due to additional, continuing leaks in the heat exchanger of the
waste evaporator (to which the auxiliary boiler also provides process
steam), the licensee's efforts to decontaminate the auxiliary boiler
feedwater had been ineffective.
Maintenance of proper boiler chemistry was difficult because blowdown
options were severely restricted due to the contamination. As a result, a
boiler tube failure caused on the order of 100 millicuries of radioactive
material to be released off-site via the auxiliary boiler fire box and
smokestack in the form of steam. This resulted in increased environmental
levels of cesium and activation products being detected as far as eight
miles downwind from the site boundary.
Action to be Taken by Licensee with an Operating License
1. Review your facility design and operation to identify systems that are
considered as nonradioactive (or described as nonradioactive in the
FSAR), but could possibly become radioactive through interfaces with
radioactive systems, i.e., a nonradioactive system that could become
contaminated due to leakage, valving errors or other operating
conditions in radioactive systems. In particular, special consideration
should be given to the following systems: auxiliary boiler system,
demineralized water system, isolation condenser system, PWR secondary
water clean-up system, instrument air system, and the sanitary waste
system.
2. Establish a routine sampling/analysis or monitoring program for these
systems in order to promptly identify any contaminating events which
could lead to unmonitored, uncontrolled liquid or gaseous releases to
the environment, including releases to on-site leaching fields or
retention ponds.
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IE Bulletin No. 80-10 May 6, 1980
Page 2 of 2
3. If these nonradioactive systems are or become contaminated, further use
of the system shall be restricted until the cause of the contamination
is identified and corrected and the system has been decontaminated.
Decontamination should be performed as soon as possible. However, if it
is considered necessary to continue operation of the system as
contaminated, an immediate safety evaluation of the operation of the
system as a radioactive system must be performed in accordance with the
requirements of 10 CFR 50.59. The 10 CFR 50.59 safety evaluation must
consider the level of contamination (i.e., concentration and total
curie inventory) and any potential releases (either routine or
accident) of radioactivity to the environment. The relationship of such
releases to the radioactive effluent limits of 10 CFR 20 and the
facility's Technical Specification and to the environmental radiation
dose limits of 40 CFR 190 must also be evaluated. The record of the
safety evaluation must set forth the basis and criteria on which the
determination was made.
4. If it is determined in the 10 CFR 50.59 safety evaluation that
operation of the system as a radioactive system is acceptable (i.e.,
does not involve an unreviewed safety question or a change to the
Technical Specifications), provisions must be made to comply with the
requirements of 10 CFR 20.201, General Design Criterion 64 to 10 CFR
50, Appendix I to 10 CFR 50 and the facility's Technical
Specifications. In specific, any potential release points must be
monitored and all releases must be controlled and maintained to "As Low
As is Reasonably Achievable" levels as addressed in Appendix I to 10
CFR 50 and within the corresponding environmental dose limits of 40 CFR
190. However, if in the 10 CFR 50.59 determination it is determined
that operation of the system as a radioactive system does constitute an
unreviewed safety question or does require a change to the Technical
Specifications, the system shall not be operated as contaminated
without prior Commission approval.
Actions taken in response to Items 1 and 2 above shall be completed within
45 days from the date of this Bulletin. A verification letter shall be
submitted within an additional 15 days to the Director of the appropriate
NRC Regional Office. This letter shall document the completion of the
required actions but need not delineate the specific actions taken. The
specifics shall be documented and made available to the NRC for review
during future onsite inspection efforts.
For facilities with a construction permit, no action is required. The
Bulletin is provided for information. The subject of the Bulletin and the
action required of operating plants should prove useful in the planning of
systems designs and future operations.
Approved by GAO, B180225 (ROO72); clearance expires 7-31-80. Approval was
given under a blanket clearance specifically for identified generic
problems.
