ML19325E354
| ML19325E354 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 10/18/1989 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | Ronald Bellamy NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| C311-89-2118, NUDOCS 8911060309 | |
| Download: ML19325E354 (2) | |
Text
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,,. T SPU Nuoleer Carperetlen Nuolear
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Middletown, Pennsylvarja 17067 0191 i
717 944 7621 TELEX 44 2386 l
oc.gg Ig, gr's Direct Dlal Number:
C311-89-2118 l
U.S. Nuclear Regulatory Commission l
Attn: Ronald R. Bellamy, Chief j
Facilities Radiological Safety & Safeguards Branch Division of Radiation Safety & Safeguards Region !
475 Allendale Road King of Prussia, PA 19406 f
Dear Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 i
Docket No. 50-289 i
Response to IR 89-17 NRC Inspection Report 89-17 requested a 30-day response to unresolved item 80-30-01. The following responds to the three questions on the lower half of i
page 3 of the Inspection Report.
Question 1:
Re-evaluate effluent charcoal cartridge results in l
consideration of possible improper geometry and/or iodine t
breakthrough. Determine whether or not these phenomena t
affected past effluent cartridge sample results.
y GpuN Response:
Radiciodine Breakthrough - Radioiodine breakthrough or less I
than expected radiciodine filter efficiency has been occurring in the condenser offgas (COG) sampling system.
Radiciodine
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collected on the second radioiodine cartridge has ranged from i
0% to 11% of that collected on the first radiotodine cartridge since July 1989.
In order to quantify the radioiodine from the l
COG, the results of both installed radioiodine cartridges will A,"
be used to account for the radioiodine from the COG sampling system release point. Appropriate procedures will be established to quantify the COG radioiodine in this manner.
In addition, a procedure providing guidance on the preparation, maintenance, and testing of the radioiodine cartridges used for i
o the COG sampling system is being prepared to ensure consistent
$o reliable COG sampling hardware.
Charcoal Cartridge Geometry - GPUN is conducting testing using two sample counting geometries; (1) a face loaded geometry and o
(2) a homogeneous geometry. These two geometries are being tested with three differently oriented source radiciod be 8
cartridges (1) face loaded, (2) homogeneous, and (3) face 0
loaded and flipped at mid count. The preliminary results of these tests indicated a face loaded geometry with a face GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation
C311-89-2118...m
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loaded source or a homogeneous geometry with the same face loaded source flipped at mid count give the same results.
The t
other counting geometry tests performed indicate onrestimates or underestimates of the activity in the sources. Testing has also shown that COG radiciodine samples are face loaded samples, based on the front to back ratios of approximately 2.3 I
for the radiciodine calibration source and approximately 2.3 I
for COG samples, j
conclusion:
GPUN will include any radiciodine in the second charcoal cartridge to account for the radiciodine released from the COG system.
GPUN will calibrata and use the gamma spectroscopy l
counting system for a face loaded radioactive cartridge geometry, and count the COG samples as face loaded samples, i
based on current testing results. GPUN will also verify semi annually that the COG samples are face loaded (front to back i
ratio approximately 2.3) rather than relying on using a homogeneous geometry and manual flipping of the COG radiciodine l
samples at mid count.
I Question 2:
If results of (1) indicated past effluents have been reported incorrectly, as appropriate, provide revisions to Semi Annual Effluent Reports and re-evaluate dose assessments and provide i
revisions to the Annual Environmental Reports.
GPUN Response: Correct Past Effluent Reports - 1987, 1988, and the first half of 1989 effluent reports have been corrected and submitted to J
the NRC in GPUN letter C311-89-2090 dated August 3, 1989. This was discussed and accepted in Inspection Report 50-289/89-17.
l No further action is required. The 1989 second half effluent report has not been submitted since the year has not ended.
l This report will include the radiciodinc COG effluent as stated in the response to (1).
Question 3:
Provide the corrective actions necessary to correctly estimate efflu6nts for condenser vent stack or other cartridge effluent sampling systems if the results of (1) indicate iodine breakthrough was occurring.
GpuN Response: To correctly estimate effluents for the COG, GPUN will take the i
actions noted in response to Question 1 above.
Also, other radiciodine cartridge effluent sampling systems t
have been evaluated. All other TMI-1 effluent systems are not hot, humid systems and do not require a hot humid sample stream. These systems do ne' normally exhibit radiciodine releases.
Sincerely D.
11 Vice President & Director, TMI-1 HDH/DVH/spb:2118 cc:
W. Russell, F. Young, R. Bores 5
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