IR 05000302/1979001
| ML19294A727 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 02/01/1979 |
| From: | Ewald S, Gibson A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML19294A726 | List: |
| References | |
| 50-302-79-01, 50-302-79-1, NUDOCS 7903130010 | |
| Download: ML19294A727 (6) | |
Text
. _
UNITED STATES
- g8 Moog'o,,
NUCLEAR REGULATORY COMMISSION
,
[
REGION ll ft
,$
101 M ARIETTA STR EET, N.W.
- o,
[
ATLANTA, GEORGI A 30303
%, * w * * * /
Report No.: 50-302/79-1 Licensee: Florida Power Corporation Facility Name: Crystal River Unit 3 License No.: DPR-72 Inspection at: Crystal River 7 ite, Crystal River, Florida Inspector:
wh-j A
y S. C.Tard Date' Signed fr!
N
/77 Approved by:
A.F.gbson,SectionChief Date Signed g
SUMMAR1 Inspection on January 8 through 11, 1979 Areas Inspected
-
This routine, unanno$nced inspection involved 33 inspector-hours on-site in the areas of radiation protection, liquid radioactive waste inventory, reactor coolant system leakage, recent in-plant gas releases, and pre-viously identified items.
Results No items of noncompliance or deviations were identified.
.
79031300}o
.
-
w
.
,
.
-
.
1.
Persons Contacted Licensee Employees
- G.
P. Beatty, Jr., Nuclear Plant Manager P. F. McKee, Nuclear Technical Services Superintendent
- J. Cooper, Jr., Nuclear Compliance Engineer
- J. R. Wright, Chemical and Radiation Protection Engineer
- J. L. Harrison, Assistant Chemical and Radiation Protection Engineer
- G. H. Ruszala, Supervisor, Radioactive Waste Management
- G.
D. Perkins, Health Physics Supervisor
- R.
E. Fuller, Plant Engineer
- K. O. Vogel, Nuclear Operations Engineer
- G. M. Williams, Nuclear Compliance Plant Engineer Other persons contacted included four licensee mechanics and four contractor mechanics.
- Attended exit interview 2.
Exit Interview The inspection scope and findings were summarized on January 11, 1979, with those persons indicated in paragraph I above.
Items discussed included two unresolved items and the status of previous items.
3.
Licensee Action on Previous Inspection Findings a.
(Closed) Unresolved Item (78-30-03) Quarterly Calibration of Radiation Monitors A review by the licensee revealed that records of monitor cali-brations performed in July 1978 had not yet been filed with other calibration records.
The inspector reviewed the calibration records and had no further questions.
.
b.
(0 pen) Unresolved Item (78-30-02) Radiation Monitor Interlock Operability Discussions with licensee representatives revealed plans were in progress to rewire the interlock circuitry so the interlock relays will be failsafe.
The inspector stated this item would remain open pending completion of licensee modifications and testin..
.
RII Report No. 50-302/79-1
4.
Unresolved Items Unresolved items are matters about which more information is required to determine whether they are acceptable or may involve noncompliance or deviations. New unresolved items identified during this inspection are discussed in paragraphs 8 and 9.
5.
Unplanned Rel:ases a.
The inspector reviewed records of recent anplanned liquid and gaseous releases discussed below. The inspector discussed these events with chem-rad, operations, and maintenance personnel in addition to management representatives. The inspector's con-clusions, observations and concerns, based on these discussions and record review, are discussed in subsequent paragraphs.
Some general comnents about these releases with specific detailed information f 311ows.
b.
All liquid releases reviewed were contained on-site by the liquid radioactive waste system and, as such, posed no direct health and safety hazards. However, due to high reactor coolant specific activity, each of the liquid events resulted in the offgassing, and subsequent release, of radioactive noble gases. The reactor coolant act'ivity was as high as 40 pCi/gm, mostly entrained noble gases. The gas releases were small fractions of orf-site release limits were small quantities relative to routine planned releases.
c.
Even though the releases were small, two radiological aspects were of concern. First, since the release points were localized in plant, the potential for significant concentrations in the vicinity of the release point existed. Since the releases in-volved noble gas activity, there was no concern relative to uptake of radioactive materials, but rather a question relative
-
to assessment of the whole body immersion dose.
The inspector discussed this item in detail with licensee representatives paying particular attention to low energy beta doses. The in-spector discussed beta dose measurements and assessment with licensee representatives and noted that estimated beta doses derived from MPC calculations were fairly low compared to gamma doses for these events.
i.11 doses were well within regulatory limits.
d.
The second radiological consequence of these releades involved personnel contamination. A portion of the released nobel gas activity was krypton-88. This isotope decays with a 2.8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> half life to a particulate rubidium-88, which in turn decays with an 18 minute half life to non-radioactive strontium-88.
Person-nel in or passing through the release area were picking up Rb-88
.
.
RII Report No. 50-302/79-1
contamination, frequently requiring decontamination prior to leaving the radiation control area. While no exposure or uptake hazard was posed, due to the short half life and relatively small quantities, several workers expressed concern over the contami-nation problem. These concerns are discussed further in paragraph 8.
e.
On December 30, 1978, the Auxiliary Building Ventilation Monitor, RMA-2, alarmed and isolated the ventilation system.
Investi-gation of the alarm revealed high noble gas activity in the auxiliary building concentrated around several floor drains near the make-up system prefilters.
Further investigation revealed the cause of the release to be an overflow of reactor coolant system (RCS) liquid from the "B" RCS bleed tank and subsequent degassing through the floor drains and the auxiliary building sump. Due to high liquid inventories (see paragraph 6), the
"B" bleed tank level indicator indicated approximately 85 percent full and further review by the licensee revealed the tank level indication was spanned for total tank volume, but the ovarflow line was installed near the 87 percent level.
This resulted in the tank overflowing before level indication would show the tank to be full.
f.
On January 3,1979, water from the reactor coolant drain tank (about 800 gallons) was to be pumped to the "C" RCS bleed tank.
This should have resulted in about a one percent indicated level change.
RMA-2 alarmed at this time and no increase in tank level was observed.
Licensee representatives stated they believe the drain tank was pumped to the B-bleed tank by accident. The B-bleed tank was full at this time so any added liquid would overflow to the auxiliary building sump as discussed in the previous instance.
g.
The bleed tank inventory was reduced over several days via the
,
liquid waste processing system and the subject floor drains covered to reduce gas releases into the auxiliary building.
These steps did not completely eliminate the problem, however, and the licensee subsequently found pressure-relief valves up-stream of the make-up prefilters were leaking. This leakage was drained to the auxiliary building sump through the same drain line as the bleed tanks.
6.
Liquid Inventory a.
The releases discussed in paragraph 5 were, to some degree, caused by an abnormally high liquid waste inventory.
The in-spector discussed the specific causes and long-term implications of apparent liquid system waste capacity problem.,.
, -. _.. _.. -. - -
.
.
"
. -
RII Report No. 50-302/79-1
' ~
b.
Specific causes of the current liquid inventory include the
.
following three items: (1) The "A" side of the Spent Fuel Pool was drained for maintenance work resulting in over 200,000 gal-lons of liquid to be processed. The*C'RCS bleed tank was itsed to handle the spent fuel pool water. Unavailability of the "C" RCS bleed tank and the practice of reserving the A bleed tank for de-
'
mineralized water, left the B bleed tank for RCS liquid inventory control; (2) a controlled shutdown, resulting from a feedwater
--
heater problem, where the reactor coolant was over borated to help reduce xenon buildup. This required significant dilution to
.,
reduce boron concentration during the subsequent startup; (3) a reactor trip from full power with a resultant surge in liquid i 1 invento ry.
The liquid inventory problem was further compou:2ded by a bottle-c.
neck in the liquid waste processing system.
Liquid waste is
.,
treated by evaporation or demineralization and collected in one of two 10,000 gallon evaporator condensate storage tanks (ECST).
,.
These tanks are then isolated, recirculated, and sampled prior to l
release. Recirculation and discharge flows of the ECST's are
'
'
limited by 30 gpm capacity pumps.
Licensee representatives estimated the recirculation, sampling, and discharge capacity to
"
be about half the waste processing capacity of the evaporators and, thus to be the limiting factor on total liquid processing capacity. -
7.
Licensee Corrective Actions
_
With regard to the problems identified in paragraphs 5 and 6, the a.
licensee has implemented and plans to implement various cor-
-
rective actions.
The inspector discussed these items with licensee representatives as summarized below.
'
b.
The high reactor coolant specific activity was reduced to about
.
11 pCi/gm on January 10, still mostly entrained noble gases.
.
This was accomplished by degassing the primary system through a
_
pressurizer sample line. This has shifted the activity from the RCS to the waste gas system. The basic problem, however, is the
source of RCS activity. Licensee representv:ives stated the
'
elevated source term might be the result of increased fuel pin
-
-
leakage in four fuel elements used to replace elements from the original core. The high source term then can be expected to continue until these elements are cycled out of the core via routine refuelings. Licensee representatives stated the waste f -
gas system would be capable of handling the increased gas inventory.
.m The level indication associated with the RCS Bleed Tanks was,
.
c.
initially, administrative 1y controlled to 85 percent to preclude
_l2
-
_
_, _......
... _. -.. -.
~~~*
.
RII Report No. 50-302/79-1
tank overflows.
Level indicators were subsequently respanned so that an indicated 100 percent corresponds to the tank overflow level.
d.
The leaking pressure relief valves in the makeup system were removed January 10 for repair and maintenance.
With the makeup prefilters bypassed and the relief valve lines sealed, the gas activity in the drain lines and auxiliary building sump were decaying away, indicating no other apparent leak sources.
The ECST recirculation / discharge capacity will be increased to e.
match the system processing capacity by replacement of the 30 gpm pumps with 100 gpm pumps. The new pumps are on-site and ready for installation once the ECST's can be removed f rom service long enough for installation. T'4is change should significantly reduce any future liquid inventory problems.
8.
Worker Concerns a.
During the inspector's review of the above items, the inspector found several groups of workers had expressed concern to plant management about the gas releases.
The inspector met with two Rroups of workers to discuss these concerns. The specific per-ceived safdty concerns expressed to the inspector focused on the recurient nature of the releases, apparent difficulties in finding and solving the problem and concerns about workers being notified when releases occurred.
The first two aspects have been dis-cussed in previous paragraphs.
In addition, licensee management stated special briefings had been conducted by the Chemical and Radiation Protection Engineer to (hopefully) resolve any ques-tions the workers bad. The third item is discussed below.
b.
The inspector discussed the means of auxiliary building evac-
.
uation announcement with licensee representatives. When RMA-2 alarms an evacuation announcement over the plant public address system is made from the control room. The inspector questioned whether areas in the auxiliary building might exist where these announcements could not be heard.
Licensee representatives acknowledged the probability of such areas existing and also noted that the loudspeakers might garble a message due to being overdriven in high noise areas. The inspector discussed various evacuation signals, including a siren / alarm and/or a flashing light for high noise areas. The inspector stated that whatever system was to be used, it should provide positive assurance that all workers will be notified of hazardous conditions.
Licensee representatives acknowledged the inspector's concerns and stated the evacuation system would be promptly evaluated for audibility and appropriate corrective measures take.
.
RII Report No. 50-302/79-1
c.
Associated with the alarm audibility question, the inspector discussed with licensee representatives the means to determine if complete evacuation has occurred.
Licensee representatives stated that the only means of personnel accountability, with regard to the auxiliary building, was the pocket dosimeter log in/out sheets. These entries are made by the individual workers and are not monitored for accuracy. Licensee management stated that this could pose a problem in accounting for personnel and stated that more emphasis would be stressed on the accuracy of logged entries.
d.
The inspector. stated that the problems of evacuation announcement audibility and personnel accountability would be considered unresolved (79-01-01) pending a review of regulatory requirements and industry practices.
9.
RCS Unidentified Leakage The inspector questioned licensee representatives whether the a.
pressure relief valve leakage discussed in paragraph 5.g had been observed in RCS unidentified leakage calculations.
The inspector reviewed recent calculations of RC leakage performed as per Surveillance Procedure SP-317, "RC System Water Inventory Balance" (approved October 16, 1978).
Calculations performed January 8 and January 11, 1979 indicated a negative, unidentified leak rate of 1.04 and 1.653 gpm respectively.
Technical Specification 4.4.6.2(d) limits unidentified leakage to one gpm.
The inspector reviewed SP-317 and had no questions as to the procedure itself.
The inspector expressed concern at the relatively large negative numbers calculated and questioned whether the calculations and their bases were adequate to identify a one gpm anidentified leak. The inspector stated this item would be unresolved (79-01-02) pending review of the data and instruments used to
,
generate the data to determine if a one gpm leak could be de-tected.
Licensee representatives acknowledged the inspector's concerns and sta+ed a review of instrument calibrations and other supporting data wc ald be conducted.
.
-
w