ML18010B098
| ML18010B098 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 05/14/1993 |
| From: | Habermeyer H CAROLINA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NLS-93-129, NUDOCS 9305210059 | |
| Download: ML18010B098 (20) | |
Text
ACCEI ERAT DOCUMENT DISTRI UTION SYSTEM REGULAT INFORMATION DISTRIBUTION iSTEM (RIDS)
ACCESSICiN NBR:9305210059 DOC.DATE: 93/05/14 NOTARIZED:
NO FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina AUTH.NAME AUTHOR AFFILIATION HABERMEYER,H.W.
Carolina Power
& Light Co.
RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Forwards response to NRC 921125 request for addi info re ODCM.All software changes planned per response will be incorporated into new ODCM software package by end of 1993.
DISTRIBUTION CODE:
A009D COPIES RECEIVED:LTR 1
ENCL SIZE:
TITLE: OR/Licensing Submittal:
Appendix I (ODCR)
NOTES:Application for permit renewal filed.
DOCKET 05000400 05000400 RECIPIENT ID CODE/NAME PD2-1 LA LE,N COPIES LTTR ENCL 1
1 2
2 RECIPIENT ID CODE/NAME PD2-.1 PD COPIES LTTR ENCL 1
1 INTERNAL: ACRS NRR/PDV OGC/HDS1 RON.g DRSS/RPB EXTERNAL: EGGG AKERS,D NUDOCS-ABSTRACT 1
1 1
1 NRC/PDR PNL BAKER,D A 3
3 NRR/DRSS/PRFB 1
1 OC AQ4B 1
0 g+"'@JAN 0 1 1
1 1
1 1
1 NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 504-2065) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'7 NEED!
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 17 ENCL 15
0
Carolina Power & Light Company P.O. Bcx 1551
~ Raleigh, N.C. 27502 H. W. HABERMEYER,JR.
Vice President Nuclear Senrices Department MAY 14 1993 SERIAL: 'LS-93-129 United States Nuclear Regulatory Commission ATTENTION:
Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT DOCKET NO. 50-400/LICENSE NO, NPF-63
RESPONSE
TO REQUEST FOR ADDITIONALINFORMATION REGARDING THE SHNPP OFFSITE DOSE CALCULATION MANUAL Gentlemen:
Carolina Power
& Light Company (CP&L) is in receipt of your November 25, 1992 request for additional information regarding the Shearon Harris Nuclear Power Plant (SHNPP) Offsite Dose Calculation Manual (ODCM).
This correspondence provides CP&L's response to that request on a schedule consistent with discussions with the NRC staff as referenced below.
Both the response schedule and the responses to many of the questions were the focus of two conference calls between CP&L, the NRC staff and the EG&G technical reviewers on March 26',
~993 and April 20,1993.
CP&L agrees that the present ODCM should be modified.
Our responses to each request for information is provided in the enclosure to this letter.
All software changes that are planned per our response to these comments will be incorporated into the new ODCM software package by the end of 1993, They will not be retrofitted into the existing software package.
However, in the
- interim, CP&L will implement administrat:ive procedural steps where necessary to ensure compliance with the requirements of 10 CFR 20 and 10 CFR 50, Appendix I.
CP&L will change the A~ component as described in the enclosure by July 1, 1993.
Other items involve changes to the text of the ODCM and will be implemented as applicable sections of the ODCM are revised.
This will be completed by July 1,
- 1994, Questions regarding this matter may be referred to Mr. R.
W. Prunty at (919) 546-7318.
SDC/sdc Enclosure
~00092 Ebneter Le Tedrow 9305' 05000000 PDR:.
cc:
Mr. S.
D.
Mr. N. B.
Mr. J.
Yours very truly, H.
W. Habermeyer, J
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~ g
Enclosure to NLS-93-129 Cate or A Comments In the methodology of Section 2.2.1, the dilution flow used for potable water consumption should be limited to the flow of the Cape Fear River.
(Note: An alternative dose calculation methodology is recommended).
(4.5)
Response
The ODCM will be changed so that the dilution flow used for potable water consumption will be limited to the flow of the Cape Fear River.'n the ODCM, dilution has been calculated in equation 2.2-1 using the D component of the Az~ factor, and the F~ factor.
D is the inverse of the dilution factor, which is Harris Lake discharge flow (via Buckhorn Creek), divided by the flow of the Cape Fear River.
Min. Ca e Fear River Flow 600cfs 3 95 Avg. Harris Lake Discharge Flow 43cfs The Harris Lake average discharge flow of 43 cfs is as per the FSAR.
The minimum flow of the Cape Fear River (600 cfs) is the minimum flow guaranteed by the U.S.
Army Corps of Engineers after completion of the comprehensive plan for the development of water resources for the Cape Fear River Basin.
This dilution will be retained in the calculations.
The F~ dilution factor includes an A~ component, whose purpose is to take credit for the dilution of the Harris Lake.
The Az component is identified as the "applicable factor" in Section 4.3 of NUREG 0133, and was further discussed in pre-licensing discussions with the NRC.
Because of the low turnover of the lake, this component has been found to be not applicable.
Using this component will introduce too much dilution into the dose
- equation, resulting in lower predicted doses.
The Aq component will be changed to a value of 1, which will have the effect of eliminating any additional dilution.
Setting Az to 1 will also have the effect of "correcting" the problem discussed in 2 and 3
below.
In LADTAP calculations, average or minimum flow values of the Cape Fear River will be used, If available in a timely manner for completion of the Semiannual Report, actual measurements of the Cape Fear River flow as measured at Lillingtonwill be used in the dilution calculations.
If actual flow measurements are not available, the long-term average flow of the Cape Fear River, which is approximately 3100 cfs, will be used.
This will give a dilution of 3100/43
= 72.
This will be used as the dilution for the appropriate pathways in the ALARA and downstream receptor calculations.
The assumptions used will be explained in the Semiannual Report as required.
Page 1
kik
Enclosure to NLS-93-129 2.
The methodology of Section 2.2.1 to determine doses via the fish pathway should account for the fact that fish live in the steady-state radionuclide concentration of Harris Lake.
Reg Guide 1.113 contains methodology to determine the steady-state concentrations.
(4.5) 3.
The methodology of Section 2.2.1 to determine doses via the potable water pathway should be based on releases from Harris Lake at the steady-state concentrations.
(4.5)
Response
Items 2 and 3 are similar and will be answered together.
SHNPP will retain the present ODCM methodology and equations,
- and, as discussed in the response to 1 above, change the A~ component in the F~ factor to 1.
This will be a suitable substitute for making all of the specific changes described in the TER ~
The only change to our ODCM software will be to change the A~ value that currently exists in an ODCM data table.
The Az component description in the ODCM will be rewritten to indicate its new usage.
Doses were calculated for 1992 using the ODCM methodology and different Az values.
The "old" ODCM methodology used an Az value of 95.
Setting A~ to 1 will raise the predicted doses.
The new doses were compared against LADTAP calculations, with the LADTAP parameters set as identified in this response.
The ODCM doses with the Az component set to 1 will be between 1.4 and 3.5 times more conservative (higher) than the doses calculated using LADTAP.
This difference will provide a suitable amount of conservatism to prevent the ODCM doses
-from inadvertently exceeding regulatory limits.
4.
The error in the dose calculation for water consumption by the teen and child age groups (which, gives zero dose) should be corrected.
(4.5)
Response
This will be corrected in future runs of LADTAP.
5.
The inconsistencies between the methodology of the ODCM and LADTAP II calculations should be eliminated.
(4.5)
Response
Since the ODCM and LADTAP use different methodologies, not all of the differences can be eliminated.
Section 2.2.1 of the ODCM was reviewed and compared against the methodology of LADTAP.
The guidance of Reg Guide 1.109, Reg Guide 1.113, NUREG 0133 and the FSAR was also examined.
The ODCM program is used as a "yardstick" throughout the year for each release to measure compliance with 10 CFR 50, Appendix I doses, LADTAP is used to calculate the doses for determining annual compliance.
As such, the doses resulting from using the ODCM methodology needs to be higher than the "official" (LADTAP) calculations.
SHNPP will make the appropriate changes so that the calculations of the ODCM are equal to, if not greater
- than, the calculations from LADTAP.
The differences between the ODCM and LADTAP methodologies will be described in the ODCM.
Page 2
, w>
Enclosure to NLS-93-129 The ODCM software will continue to use the "modified" NUREG 0133 equation with conservative assumptions.
It calculates the dose to a single maximum individual. It does not calculate doses in a steady-state environment, nor does it calculate reconcentration factors.
Specific changes to the ODCM include changing the Dose equation 2.2-1 as discussed in the response to 1, 2,
and 3 above and ensuring that the ALARA (maximum exposed) individual will be the individual that consumes fish caught in the Harris Lake (dilution of 1.0) and receives their drinking water from Lillington (dilution of 13.95).
The current SHNPP LADTAP Program uses the guidance of Reg Guide 1.109 and Reg Guide 1.113 to calculate the dose to a maximum individual in all age groups, downstream receptors, and integrated populations.
It will calculate doses based on a steady-state environment using the completely mixed model and reconcentration
- factors, as per Reg Guide 1.113, and will use average, rather than minimum values for the Cape Fear River Flow.
Some specific changes to LADTAP will be to ensure that LADTAP uses the same assumptions in the ODCM, especially the assumptions for the ALARA individual.
Also, the pathways for all applicable age groups would be used.
6.
Input parameters for LADTAP II should be included in the ODCM. (4.5)
Response
SHNPP agrees and as discussed with the NRC on March 26,
- 1993, CPSL will include the LADTAP input'parameters in the ODCM either directly or by reference.
Parameters which are variable (source term, actual flow rates, etc) will be described in the ODCM or a reference
- document, but the actual values will be listed in the applicable Semiannual Radioactive Effluent Release Report.
7.
The method used to determine the release rate and total release of the GALE code distribution of noble gas radionuclides should be described in Sections 3.2.1 and 3.3.1.
(4.4.1 and 4.6.1)
Response
The method SHNPP uses to determine the release rate and total release of the GALE code distribution of noble gas radionuclides will be included and described in Sections 3.2.1 and 3.3.1.
8.
The methods used to determine the release rate and total release of radionuclides other than noble gas should be described in Sections 3.2.2 and 3.3.2.
These should be based on the sampling and analysis required by TS 4.11.2.1.2.
(4.4.2 and 4.6.2)
Response
The method SHNPP uses to determine the release rate and total release of the radionuclides other than noble gas will be included and described in Sections 3.2.2 and 3.3.2.
A statement will be added that says that this is based on the sampling and analysis required by TS 4.11.2.1.2.
r Page 3
Enclosure to NLS-93-129 9,
The method used to determine the radionuclide distribution of the total releases of radionuclides other than noble gases should be addressed in Section 3.3.2.
(4.6.2)
Response
The method SHNPP uses to determine the release rate and total release of radionuclides other than of noble gas will be included and described in Sections 3.2.2.
10.
All GASPAR parameters used for the calculations of doses due to noble gases should be included in Section 3.3.1.
(4.6.1)
Response
SHNPP agrees and as discussed with the NRC on March 26,
Parameters which are variable (source term, actual flow rates, etc) will be described in the ODCM or reference
- document, but the actual values will be listed in t'e applicable Semiannual Radioactive Effluent Release Report.
11.
The most recent version of the GASPAR code, GASPAR II, should be used for the calculations of doses due to gaseous effluents.
(4.6)
Response
CP&L's version of GASPAR was reviewed against GASPAR II.
The ma)or difference between GASPAR and GASPAR II were differences in Dose Conversion Factors (DCF's).
The DCF's were updated in our version of GASPAR.
No difference in methodology was found so there would be no significant gain in updating the to the revised code.
Since our existing software has been verified, no additional changes are deemed necessary.
12.
All GASPAR parameters used for the calculation of doses due to radionuclides other than noble gases should be included in Section 3.2.2.
(4.6.2)
Response
SHNPP agrees and as discussed with the NRC on March 26,
Parameters which are variable (source term, actual flow rates, etc) will be described in the ODCM or reference, but the actual values will be listed in the applicable Semiannual Radioactive Effluent Release Report.
Page 4
Enclosure to NLS-93-129 Cate or B Comments The methodology in Section 2.1.1 to determine setpoints of the liquid effluent radioactivity monitors should define setpoints corresponding to concentrations greater than those existing in the undiluted liquid effluents, so continuous alarm does not occur.
(4.1)
Response
The methodology as discussed in Section 2.1.1 does exactly what the comment suggests to avoid continuous alarms, i.e.,
the methodology defines setpoints corresponding to concentrations greater than those existing in the undiluted liquid effluents.
SHNPP does not discharge liquid effluents with radiation monitors in alarm; nor does the methodology determine setpoints that would lead to continuous alarms.
In determining the monitor's alarm
- setpoint, the methodology utilizes a multiplier which adjusts the setpoint to reflect the minimum expected dilution rate over and above the minimum dilution required to comply with regulatory standards.
Therefore, no changes are necessary or planned in the setpoint methodology.
- However, we will to modify the description of the methodology in the ODCM to avoid any further misinterpretation.
This'omment was discussed with the NRC during the phone conversation of March 26,
- 1993, and again with the NRC and EG&G on April 20, 1993 and April 29, 1993. It was agreed that there is no technical problem, but the wording and description in the setpoint methodology led EG&G to their original conclusion.
It was also agreed that a statement will be placed in the setpoint methodology description that. says that the D~~~, / D,~, factor, a multiplier based on the ratio of the amount of dilution available for the release to the amount of dilution required by the release, should always be greater than 1.
2.
Section 2'.1 should require at least administrative controls to prevent simultaneous batch releases.
(4.1)
Response
SHNPP does have in place programmatic and procedural restrictions to prevent simultaneous batch releases.
The ODCM states in Section 2.0 that concurrent (simultaneous) batch releases should not occur at
- SHNPP, The radwaste procedures which govern the release of liquid effluent tanks have, as an initial condition, the requirement that "No batch discharges are being made from"...any of the other batch release points.
Since plant procedures control the release of the liquid effluent tanks consistent with ODCM requirements, the additional administrative controls suggested in the comment do not need to be repeated in Section 2.1.1 of the ODCM.
Page 5
Enclosure to NLS-93-129 3.
In Section 2.1.1 the long-term buildup of radionuclides in Harris Lake should be considered in the calculations of setpoints for the liquid effluent radioactivity monitors.
(4.1)
Response
SHNPP has and continues,to monitor for potential long-term buildup of radionuclides in the Harris Lake.
The Harris Lake is sampled continuously, and analyzed quarterly, for gamma isotopes to identify any radionuclide buildup that might occur.
To date, based on plant operation and environmental monitoring since
- 1986, there has been no detectable buildup of radionuclides, other than tritium, observed in the Harris Lake.
Since the setpoint calculation includes a "safety factor" of 2, i.e.,
the radiation monitor will alarm when the effluent stream exceeds 0.5 EC, this will more than account for the five to ten percent increase that could be attributable to long-term buildup.
Also, there is additional conservatism built into the setpoint calculation,'ncluding a correction for the possibility of having a continuous release and a batch release simultaneously.
Since the Harris Lake isotopic concentrations, including those of tritium, are so low there is no need to directly address lake concentrations in determining effluent alarm setpoints.
These comments were discussed with the NRC during the phone conversations of March 26, 1993 and April 20, 1993.
Based on the above discussions, no changes to the ODCM are necessary.
The definition of Cz for equation 2.1-14, Section 2.1.1 should require that the concentration of radionuclide -"i" be determined by the analysis specified in Table 4.11-1.
(4.3)
Response
The ODCM states in Section 2.0 that "the radioactive liquid waste sampling and analysis required for batch and continuous releases are found in Table 4.11-1 of the Technical Specifications,"
The Cz factor is one of many instances to which the statement in Section 2.0 applies.
Since Section 2,0 states the overall requirements to be met, it is unnecessary to repeat the reference to Table 4.11-1 in either the definition of C< or the other instances where it applies.
Therefore, it is CPSL's intent not to revise the definition of C~.
5.
The definition of V> for equation 2.1
~ 14, section 3.1.1 should specify "undiluted liquid effluent",
(4.3)
Response
This definition will be changed.
6.
Sections 3.2.1 and 3.3.1 should include commitments to determine the distribution and release rates of noble gas radionuclides in gaseous effluents from the sampling and analysis specified in TS Table 4.11-2 if this is feasible.
(4.4.1 and 4.6.1)
Response
A statement will be added to sections 3.2.1 and 3.3.1 that says that the radionuclide mix and releases rates are based on the sampling and analysis required by TS Table 4.11-2, or is based on Page 6
~1 Enclosure to NLS-93-129 default assumptions of activity levels when sampling and analysis does not show any radionuclides (i.e., below LLD).
7.
Section 6.1.1 should include a requirement that any report of calculations required by TS 3.11.4 will include a complete statement of the assumptions and parameters used in calculating doses for the report.
(4.9)
Response
Section 6.1.1 will be revised to include a requirement that any report of calculations required by TS 3.11.4 will include a
complete statement of the assumptions and parameters used in calculating doses for the report.
Page 7
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Enclosure to NLS-93-129 Cate o
C Comments 1.
The first sentence of Subsection 5, Section 2.1.1 should be restated in terms of Item 1 of the Note at the end of 10 CFR 20, Appendix B.
(4.1)
Response
This item will be rewritten.
2.
The HSP in equation 2.1-7, Section 2.1.1, should apparently be identified as the monitor setpoint in "equivalent Cs-137 concentration".
(4.1)
Response
Although this is another manner to refer to the monitor high alarm setpoint, it differs from the current terminology used by SHNPP.
The current terminology is well understood by the plant personnel that deal with this equation.
Changing the definition could add unneeded confusion without providing any real benefit.
Therefore, CP6L does not intend to revise the definition HSP~ in the ODCM.
3.
A definition of Mq for Equation 3.3-1 should be added to section 3.3.1.
(4.6.1)"
Response
This definition will be added, The word "average" should be replaced with "total" in the definition of the noble gas releases for equation 3 '-1 and 3.3-2 in Section 3.3.1; i.e.,the defxnitions from NUREG-0133 should be corrected.
(4.6.1)
Response
The word "average" will be replaced with the word "total" in this definition.
Cate or D Comments No Category D items were identified.
Page 8