ML17286B060
| ML17286B060 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 04/09/1991 |
| From: | Thomas Young EG&G IDAHO, INC., IDAHO NATIONAL ENGINEERING & ENVIRONMENTAL LABORATORY |
| To: | Essig T NRC |
| Shared Package | |
| ML17286B059 | List: |
| References | |
| EGG-PHY-8032, TEY-11-91, NUDOCS 9110070040 | |
| Download: ML17286B060 (21) | |
Text
Idaho National Engineering Laborarory April 9, 1991 Mr. T.
H. Essig Radiation Protection Branch Mail Stop 10D4 U.
S. Nuclear Regulatory Commission Washington, D.
C.
20555 FINAL LETTER REVIEW OF WNP-2 ODCM REVISION 8 TEY-11-91
Dear Mr. Essig:
Attachment 1 is a Letter Review of the complete Washington Public Power Supply System Nuclear Project, Unit-2 (WNP-2)
ODCM, updated through Revision 8
(Amendment 8 in the licensee's terminology),
submitted by Washington Public Power Supply System (WPPSS),
the licensee for WNP-2.
Revision 8 was transmitted to the NRC with a letter from J.
W. Baker
{WPPSS) to Document Control Desk (NRC),
dated February 22, 1991.
A complete ODCM was submitted.
Revisions 7 and 8 were submitted after a review of, Revision 6,
which is documented in a letter from D.
W. Akers (EGG) to W.
Meinke
{NRC), dated May 26, 1989.
Changes in Revisions 7 and 8
were mainly of the following four types:
(1) editorial additions to clarify meaning and/'or to make the wording in the ODCM exactly the same as in the technical specifications, (2) additions of data for dose calculations, (3) corrections or updates of numerical values, (4) changes or e~ lanations in response to a letter from R.
B. Samworth (NRC) to G.
C.
Sorensen (WPPSS),
dated September 12,
- 1989, concerning unresolved items in the review of ODCM Revision 6.
Attachment 2 is included for convenient reference.
It includes previous correspondence concerning the items discussed in the review of Revi'sion 6.
This correspondence includes:
(a) the initial description of the deficiency from the review of Revision 4 in EGG-PHY-8032, dated March 1988; (b) applicable rationales furnished by WPPSS to justify changes made by Revisions 5 and 6; (c) the discussion of the status of the deficiency in the
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9110070040 PDR ADQCK 05000DR P
Idaho Falls, /D 83415
EG&G Letter Report dated Ray, 26, 1989; and (d) applicable rationales furnished by the 'licensee to justify changes made by Revision 7. It also includes Section 7.0 of the WNP-2 Semi-annual Effluent Report for Jul-Dec
- 1990, which describes and gives the reasons for all changes made in the ODCM by Revision 8.
The most significant deficiency in the WNP-2 ODCM, updated through Revision 8, appears to be due to an oversight in the correlation of parameters in the WNP-2 calculations.
The "river dilution" of 2000 given in Table 2-3 for use in LADTAP II is inconsistent with the near-field liquid dilution factor of 500 used in Section 2.4, and results in calculation of doses due to fish consumption that are a factor of 4 too low.
The licensee should be aware that the ODCM methodology to calculate the maximum organ dose to an individual due to releases of radioactive material in gaseous effluents gives conservative (large) doses.
This is because the doses are calculated for a "pseudo-organ" for which the dose commitment due to each pathway and radionuclide is equal to the highest dose commitment to any real organ for that pathway and radionuclide.
Sincerely
- yours, T.
E.
Yo g
Radiological Physics Attachments:
As stated cc: J. J.
Hayes, Jr.,
NRC-HQ, MS 10D4
Attachment 1
TEY-11-91
'April 9, 1991 Page 1 of 5
LETTER REVIEW OF WNP-2 ODCM, REVISlON 8.
In a letter from R.
B.
Samworth (NRC) to G.
C. Sorensen (WPPSS),
dated September 12,
- 1989, the NRC requested that WPPSS consider comments in the review of the WNP-2 ODCM Revision 6, documented in a Letter Review by EGaG Idaho dated May 26, 1989.
Subsequently, the licensee submitted ODCM Revision 7 with a letter from C.
M.
Powers (WPPSS) to Document Control Desk (NRC), dated February 26, 1990; and Revision 8, with a letter from J.
W. Baker (WPPSS) to Document Control Desk (NRC), dated February 22, 1991.
Complete ODCMs were submitted wi th these revisions.
Changes from Revision 6 were mainly of the following four types:
(1) editorial additions to clarify the meaning and/or to make the wording of the ODCM consistent with that of the WNP-2 Technical Specifications, (2) additional data for dose calculations, (3) corrections or updates of numerical values, and (4) changes or explanations in response to the letter from R.
B.
Samworth (NRC) to G.
C. Sorensen (WPPSS),
dated September 12,
- 1989, concerning items discussed in the EGaG Letter Review of ODCM Revision 6.
In addition to the identification of typographical errors introduced by Revisions 7 and 8 and the evaluations of responses to previous
- reviews, the following information is furnished for the licensee:
The ODCM methodology to calculate the maximum organ dose to an individual due to releases of radioactive material in gaseous effluents gives conservative (large), doses.
This is because the doses are calculated for a "pseudo-organ" for which the dose commitment due to each pathway and radionuclide is equal to the highest dose commitment to any real organ for that pathway and radionuclide.
A summary of evaluations of the status of the licensee's ODCM Revision 8 with respect to the items discussed in the Letter Review of Revision 6 is given in Section 1 below, followed by more detailed evaluations in Section 2.
Section 3 identifies errors introduced by Revisions 7 and 8
The only change required in the ODCM, updated through Revision 8, other than the correction of typographical errors is the correction of the dilution factor in'able 2-3 from 2000 to 500, so it agrees with the value in Section 2-4.
Attachment 1
TEY-11-91
, April 9, 1991 Page 2 of 5
1.
Summar of the Status of Items Discussed in the Review of ODCM Revision 6.
Item 2.
Acceptable in principal, but input for LADTAP II is inconsistent with other parameters and results in calculation of doses due to fish consumption that are a
factor of 4 too low.
An additional improvement in the calculation of doses due to fish consumption is recommended.
Item 4.
(1)
(2)
(3)
(4)
Four items concerning dose parameters in Tables 3-5a through 3.5d.
Acceptable; accounts for bremstrahlung from Y-90.
Acceptable; consistent with GASPAR II methodology.
Acceptable; corrected in Amendment 6.
Acceptable.
Item 9.
Acceptable.
Item 11. Acceptable; methodology is more conservative than required.
Item 17. Acceptable; but Table 3-8 should be made consistent with Table 3-9.
2.
Evaluations of the Status of Items Discussed in the Review of Revision 6.
Evaluation of Res onses to Item 2.
Input for LADTAP II needs corrected.
Also the methodology for liquid dose calculations in Section 2.4 should be improved.
Acceptable in principal.
The only essential ch-.ge associated with Item 2 is the correction of the value of "River Dilution" for "Boating and Aquatic Food" in Table 2-3. It should be changed from 2000 to 500, so it agrees with the value of 500 specified for the "applicable factor" in Section 2.4.
Note:
The reviewer performed an independent calculation of the dose commitments due to liquid effluents via the fish consumption and potable water pathways for releases during the third and fourth calender quarters of 1989.
The doses calculated were approximately 1, 2, 4,
and 8 times the values
Attachment 1
.TEY-11-91 April 9, 1991 Page 3 of 5
reported in Table 6-1 of the WNP-2 semiannual effluent report for the second six months'f 1989.
Inductive reasoning leads to the conclusion that the discrepancies are due to the following reasons:
(a) the licensee' calculations were performed using a "river dilution" of 2000, as given in ODCM Table 2-3, and (b) for some releases, the licensee performed dose calculations using blowdown flows that were approximately twice as large as the average blowdown flow during the third quarter.
The following recommendation should also be considered.
The definition of Fl in ODCM Section 2.4 identifies the dilution flow as "the product of the average flow from the site discharge structure to unrestricted receiving waters times 500," where 500 is the "applicable factor" defined in Section 4.3 of NUREG-0133.
The licensee's bases for the applicable factor of 500 are the average blowdown flow for the 7/1/86 6/30/87 period (i.e.,
1.8 cfs),
and the guidance of Section 4.3 of NUREG-0133.
Section 4.3 of NUREG-0133 requires that the product of the blowdown flow and the "applicable factor" shall be 1000 cfs or less.
It was noted in the Letter Review of Revision 6 that the average blowdown flow sometimes exceeds 2 cfs for a calendar quarter or calendar year.
Therefore, to ensure that the guidance of NUREG-0133 is followed, the quantity "ft x 500" in Equation 6 of Section 2.4 should be limited to ( 1000 cfs.
Evaluation of Res onses to Item 4.
The four parts of this item are discussed below.
(1) Acceptable.
The licensee's use of the Y-90 ground plane dose factor for Sr-90 accounts for the bremstrahlung from the beta decay of Y-90.
(2) Acceptable.
The ground plane dose parameters in OD(.'.
Tables 3-5a through 3-Sb are consistent with the methodology of GASPAR II.
This is considered an acceptable reference, although there are inconsistencies with the guidance of NUREG-0133 and Regulatory Guide 1.109, Rev.
1.
(3) Acceptable.
The inhalation dose parameters are correct in ODCM Revision 8, Tables 3-5a through 3-5d.
Attachment 1
TEY-11-91
,April 9, 1991 Page 4 of 5
(4) Acceptable.
An independent calculation of the vegetable dose parameters (Ri
) in ODCM Tables 3-5a through 3-5d, using the methodology of GASPAR II, gives good agreement with the values in Revision 8 of the ODCM.
This agreement was obtained by using 0.42 "Fraction of year leafy vegetables are grown" from Table 3-9.
This value is inconsistent with the fL 1.0 in Table 3-8.
The ODCM should clarify the relation between the two values by stating that the 0.42 in Table 3-9 is for use to calculate doses on an annual basis.
For consistency, the value of fI, in Table 3-8 should be changed to 0.42.
Evaluation of Res onses to Item 9. Acceptable.
In principal, the blowdown flow used in the calculations should be limited so the total dilution cannot exceed the river flow.
However, with dilution of the maximum possible blowdown flow (16.7 cfs) in the average river flow (>100,000 cfs) the calculated dose due to potable water consumption is only about 1% of the dose due to fish consumption.
Therefore, the releases are controlled by the dose due to fish consumption and the slight error in the dose due to potable water consumption is negligible.
Evaluation of Res onses to Item 11.
Acceptable.
There is no problem associated with this item.
The licensee does not use temporary liquid storage tanks.
In the event that such tanks are used in the future, the methodology in the ODCM to limit their contents is more conservative than required.
Evaluation of Res onses to Item 17.
Acceptable.
This item noted that some environmental monitoring locations are very slightly (approximately 4%) farther from the site.
than specified in Technical'pecification Table 3.12-1.1.
The licensee states that the distances given in the ODCM were obtained by measurements on a map, which are not highly accurate.
Even if the distances were exact, the locations should be considered to meet the intent of NUREG-0473 and the licensee's technical specifications.
Attachment 1
TEY-11-91 April 9, 1991 Page 5 of 5
3.
Review of Additional Chan es Made to the ODCM in Revisions 7 and 8.
The licensee gives the rationale for twenty-four changes made in Revision 7 and eight changes made in Revision 8.
Most of the changes clarify the meaning of the ODCM text or change the wording to make the ODCM agree exactly with wording in the technical specifications.
Other changes update information in the ODCM.
The changes generally improve the ODCM.
Revision 7 introduced inconsistencies between Table 3-3 and Tables 3-10 through 3-12.
These inconsistencies were removed by Revision 8.
The following typographical errors were noted during the review of Revisions 7 and 8:
(1) bt in the last line on page 6 should not be a
subscript.
(2)
The mu in the definition of Ko on page 8 is misplaced.
(3)
A division sign is omitted from the definition of Ko on page 8.
(4)
The last part of the sentence above For Tritium on p""pp*"1!'""d"""!"
are tabulated in Table 3-5."
(5)
The following inconsistencies exist between Table 5-1 and Table 5-2:
- a. Location 29 is shown for surface water in Table 5-1, but not in Table 5-2.
- b. Location 27 is shown for drinking water in Table 5-1, but not in Table 5-2.
- c. Location 9B is shown for milk in Table 5-1, but 9C is shown in Table 5-2.
- d. Locations 9C and 37 are shown for garden produce in Table 5-1, but locations 9B,
- 37A, and 37B are shown in Table 5-2.
- e. Location 9A is shown for soil in Table 5-1, but 9C is shown in Table 5-2.
Attachment 2
~
TEY-11-91 Nay 9, 1991 t
'age 1 of 17 ll DISCUSSION OF DEFICIENCY2 INTHE ODCM UPDATEDTHROUGH AMENDMENT4 DEFICIENCYIDENTIFIEDIN EGG-PHY-8030, DATEDMARCH 1988:
In Section 2.4, the definition of the parameter, Fl, in Equation 5 includes a factor of 100 times the average flow from the site structure.
According to NUREG-0133 the product of the average blowdown flow to the receiving water body and an applicable factor can be 1000 cfs or less.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDMENT5, DATEDAPRIL 1, 1988:
ATTACHMENT 3 AMENDMENT NO.
5 TO THE OFFSITE DOSE CALCULATION MANUAL Amendment No.
5 consisted of major changes incorporated to include a change in the near field dilution factor to relate to actual operating data, the addition of several radionuclides to various
- tables, a reference to the latest NUREG covering computer code LADTAP II, and the addition of a method of projecting 31 day doses due to gaseous effluent releases.
1.
Refer to IOM from G.Y.
Oldfied to Y.E.
- Shockley, subject "Applicable Factor for Use in Calculating Near Field Average Dilution Factor,"
which is attached.
(The Licensee's internal memorandum related to this change is duplicated on the followingtwo pages.)
l ttachment 2
TEY-11-91 May 9, 1991
~ Page 2 of 17 DISCUSSION OF DEFICIENCY2 INTHE ODCM UPDATEDTHROUGH AMENDMENT4 CONT.
49 sUppLY'SYSTEM INTEROFFICE MEMORANDUM GVO-87-011 DISTRIBUTION: MAlLDROP:
G DATE: August 31, 19$ 7 To: Y. E. Shockley, Supervisor, Health Physics Support (92 en<>M:
G.
Y. Oldfield,~nperv>,
ad Assessment (1020) sUBJECT:
APPLICABLE FACTOR FOR USE IN CALCULATING NEAR fIELD AYERAGE DILUTION FACTOR CI
REFERENCE:
WNP-I FILE WNP.2 FILE WNP-3 FILE WNPA FILE WNP 5 FILE HGP FILE PKWD FILE LEGALFILE ADMINFILE TE Chapman (1020)
AI Davis (927S)
RG Graybeal (927S DE Larson (1020)
File 962.2.3 GVO/LB The "applicable factor" currently specified in the Offsite.Dose Calculation Manual
'(ODCN) was calculated prior to licensing using NUREG-0133 methodology and assumed average blowdown flow of 6 cfs.
NRUEG-0133 states that "For plants with cooling
- towers, onsite ponds or
- lagoons, the factor shall be a
number such that the product of the average blowdown flow to the receiving water body, in cfs and the applicable factor, is 1000 cfs or less."
Using this method of calculation, the factor was calculated to be 1000 cfs/6 cfs
= 167.
It was apparently reduced to 100 for conservatism.
The factor can be recalculated us'ing'actual average blowdown flow.
The attached table shows blowdown flow for the previous four calendar quarters.
Using that data, the factor is calculated to be 555.
Me are initiating an ODCH revision to change the factor to 500.
pm At.achment
Attachment 2
TEY-11-91 May 9, 1991 Page 3 of 17 DISCUSSION OF DEFICIENCY2 INTHE ODCM UPDATEDTHROUCFI AMENDMENT4 CONT.)
ATTACHMENT A MNP-2 Blowdown Flow 7/1/86 6/30/87 Time Period 7/1/86 9/30/86 10/1/86 " 12/31/86 1/1/87 3/31/87 4/1/87 6/30/87 Total Blowdown Volume (a) 7.6E8 4.0E8 2.5E8 2.0E.8 Avg. Slowdown Flow (cfs) 3.4 1.8 0.9 Total for 4 (}uarters Average 1, 6Egi 4.0EBL/qtr.
1.8 cfs Applicable Factor
= 1000/avg.
blowdown flow (cfs)
Applicable Factor
= 555
TEY-11-91 May 9, 1991
,Page 4 of 17 DISCUSSION OF DEFICIENCY2 INTHE ODCM UPDATEDTHROUGH AMENDMENT4 CONT EVALUATIONFROM THE EG&G LEITER REVIEW OF AMENDMENT6, DATEDMAY26, 1989.
Item 2.
This item questioned the use of the "applicable factor" value of IOO for the near field dilution factor in Eq.
6 of the OOCM (in the definition of Fl for Eq. 5).
In Revisions 5 and 6 this factor is changed to 500.
The Licensee's rationale for changing the near field dilution factor from 100 to 500 assumes an average total blowdown flow of 1.8 cfs.
Since 500 X 1.8 cfs 900 cfs, this results in the denominator of Eq.
5 being less than the assumed flow of 1000 cfs permitted by Section 4.3. 1 of NUREG-0133 for plants with cooling towers, etc.
This limit is appropriate for WNP-2, which uses mechanical draft cooling towers.
However, the use of 1.8 cfs as the average blowdown flow is questionable, since this value was exceeded in 6 of the 16 calendar quarters and 2 of the 4 calendar years since WNP-2 began commercial operation in December 1984.
In five of the calendar quarters and one of the 'calendar years this assumption could have resulted in calculated doses within the limits of Technical Specification
- 3. 11. 1.2 for reporting periods (calendar quarters or calendar years) during which a calculation using the permitted maximum assumed blowdown flow of 1000 cfs would have given calculated doses exceeding these limits.
Therefore, the denominator of ODCM Equation 6 should be restricted to an average dilution flow of less than or equal to 1000 cfs for each reporting period.
Note also that the use of 1.8 cfs as the average total blowdown flow conflicts with the value of 2690 gpm (-5.99 cfs) given in ODCM Section 2.2.
These two values should be consistent.
LICENSEE'5 RATIONALEFOR A CHANGE MADEBYAMENDMENT7, DATEDDECEMBER 1989:
7.0 V
N TH During this reporting per1od, Amendment No.
7 was made to the Offsite Dose Calculation Manual (ODCM).
7.1 This rat1onale 1s 1ntended to provide a concise explanation of the changes made to the HNP-2 Offs1te Dose Calculation Manual (ODCM) for Amendment Number 7.
3.
Page 3; changed the average release rate from 2690 gpm (6.0 cFs) to 808 gpm (1.8 cFs) to correspond to actual operating average and to clar1fy the concern 1n Item 2 of the Technical Evaluation Report by the NRC rev1ew.
This is consistent with the 1.8 cFs value used to obtain the "applicable factor" used 1n the FII factor for equat1on f1ve (5) on page s1x (6).
TEY-11-91 May 9, 1991
,Page 5
oK 17 DISCUSSION OF DEFICIENCY 4 INTHE ODCM UPDATEDTHROUGH AMENDMENT4.
DEFICIENCYIDENTIFIEDIN EGG-PHY-8032, DATEDMARCH 1988:
~
Tables 3-Sa through 3-5d contain dose parameters for all age groups and all pathways for the maximum organ.
The reviewer was unable to reproduce the dose parameters for the milk (cow),
milk (goat), vegetable, and meat pathways.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDMENT6, DATEDNOVEMBER 1988:
Stand Alone Discussion As Per Tech Spec 6.14.
This stand alone discussion is included to provide a short explanation for the changes made to the MNP-2 Offsite Dose Calculation Manual (ODCM) in proposed amendment Ho. 6.
24.
Tables 3-5a through 3-5d, pages 64-67; the reviewer in the TER said they were unable to reproduce the dose parameters for milk (cow), milk (goat),
vegetable, and meat pathways.
The TER covered the review of the HNP-2 ODCM through Amendment Ho. 4.
These tables were changed in Amendment No.
5 and were produced using the subroutine PARTS Calculation of GASPAR II as described in I-'UREG/CR-4653, "GASPAR II-Technical Reference and User Guide",
dated March 1987.
There have been some radionuclides added to the tables and these are included in this amendment.
Attachment 2
TEY-11-91 May 9, 1991 Page 6 of 17 DISCUSSION OF DEFICIENCY4 IN THE ODCM UPDATEDTHROUGH AMENDMENT4 CONT LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDMENT6, DATEDNOVEMBER 1988:
Stand Alone Discussion As Per Tech Spec 6.14..
This stand alone discussion is included to provide a short explanation for the changes made to the WHP-2 9ffsite Dose Calculation Manual (ODCI4) in proposed amendment Ho. 6.
3.
Section 2.4, equation 5
has been rewritten with each of the terms identified the same as is in HUREG-0133, "Preparation of Radiological Effluent Technical Specifications for Nuclear Power Plants.
The definitions of some of the terms used were items of concern in the TER.
The TER reviewed the ODCN through Amendment Ho.'.
The
" applicable factor" value in the F~ term was changed in Amendment Ho.
5 from 100 to
- 500, based on actual operating data.
The F< term was an:,.item raised in the TER.
EVALUATIONFROM THE EG&G LETTER REVIEW OF AMENDMENT6, DATEDMAY26, 1989 Item 4.
The Licensee recalculated dose parameters R; in Tables 3-5a through 3-Sd.
The parameters in these tables in Revision 6 are generally between 85% and 110% of the values calculated by the reviewer with the following exceptions, which should be checked and corrected where necessary:
The ground plane parameters for Sr-90 should be zero, since this radionuclide emits only beta particles.
The ground plane parameters for I-131 and I-133 should be a
factor of 2 larger than reported in the tables, since the factor of 0.5 to account for the elemental iodine fraction (allowed by.Regulatory Guide 1. 109) applies only to food pathways.
Inhalation dose parameters for Zr-95 and Nb-95 for the child age group appear to be about 1/3 and 1/5, respectively, of the correct values.
Vegetable dose parameters are less than 85% of the reviewer's values for Fe-59, Zr-97, Mo-99, Te-127, Te-131m, I-133, and La-140 for one or more age groups.
Similarly, vegetable dose parameters are greater than 110% of the reviewer's values for Cr-51, Co-58, Zn-65, Sr-89, Zr-95, Nb-95, I-131, Cs-136, Ba-140, and Ce-141 for one or more age groups.
(Several of the differences between the WNP-2 values and the reviewer's values may be due to the use of different delay times in the vegetable dose pathway).
1
Attachment 2
TEY-11-91 May 9, 1991 Page 7 of 17 DISCUSSION OF DEFICIENCY9 INTHE ODCM UPDATEDTHROUGH AMENDMENT4 DEFICIENCYIDENTIFIEDIN EGG-PHY-8032, DATEDMARCH 1988:
In Section 2.4 of the ODCM, the dilution factor, Dw, used in Equation 7 is defined as the dilution. factor from the near field area to the nearest potable water intake and is given as 200.
A reference must be included to support or justify the value.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDMENT5, DATEDAPRIL 1, 1988:
ATTACMMEHT 3 AMENDMENT HO.
5 TO TME OFFSITE DOSE CALCULATIOH MANUAL Amendment Ho.
5 consisted of major changes incorporated to include a change in the near field dilution factor to relate to actual operating data, the addition of several radionuclides to various
- tables, a
reference to the latest HUREG covering computer code LADTAP. II, and the addition of a method of projecting 31 day doses due to gaseous effluent releases.
3.
The change on page 8 for Dw value is to be changed from 200 to 120.
If the 20,000 dilution factor obtained by dividing 6 cfs into 120,000 cfs (average river flow) and the average blowdown flow is 1.8 cfs, then the river dilution becomes 66,666 (use 60,000).
The Dw "dilution factor from near field area to the nearest potable water intake" was obtained by dividing 20,000 by 100.
If we now use 500 as the applicable factor for calculating the Near Field Dilution Factor, then Dw would become 500 divided into 60,000, which is equal to 120.
As the Dw factor is used in the equation (7) for determini ng Aij value in Table 2-2, these value's were'han'ged as requir'ed.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDMENT6, DATEDNOVEMBER 1988:
Stand Alone Discussion As Per Tech Spec 6.14.
This stand alone discussion is included to provide a short explanation for the changes made to the MNP-2 Offsite Dose Calculation Manual (ODCM) in proposed amendment No. 6.
4 Page 8,
Dw value:
the original Dw value was derived prior to operation.
Radiological Prot.rans Calculation Log 98-3 has been completed to provide input parameters for the LADTAP II computer program based on operating data.
The Calculation Log 88-3 can be used as the applicable reference for the river dilution factors.
Table 2-2, which provides Ingestion Dose Factors (Aij) reflects the Dw value change to 100.
~ i io Uf)Belle 2
VCY-11-91 May 9, 1991 Page 8 of 17 DISCUSSION OF DEFICIENCY9 INTHE ODCM UPDATEDTHROUGH AMENDMENT4 CONT.
LICENSEE'S RATIONALESFOR CHANGES MADEBYAMENDMENT6, DATEDNOVEMBER 1988:
6.
Section 2.7.2 Plant Parameters (pg.
17)'have some changes that are based upon operating data and have been included in the Calculation Log 88-3.
The Richland drinking water dilution factor was determined to be 50,000 by using the average river flow from July 1986 through June 1987 as 103,810 cfs and the average total blowdown flow of 1.8 cfs.
Therefore, 103,810 cfs 1.8 cfs
= 57,672.
This value is rounded down to 50,000.
Page 18, the transit time to Richland was changed from 4.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> to 4.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />.
River speed is about 2.9 mph at a flow of 120,000 cfs.
Assuming the same speed for 103,810
- cfs, and it is about 12 miles to Richland, then the transit time would 4.1 hours1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />; rounded to 4.0 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />.
The 75,000 number was not the total population affected from liquid effluents.
It is the approximate population consuming drinking water downstream from the plant and was therefore deleted from the sentence.
Reference Table 5.2.6 of WHP-2 Environmental Report, Operating License Stage.
Calculation Log 83-1 has been revised with Calculation Log 88-3.
8.
Table 2-2, pages 29, 30 and 31 required revising due to the change in the Ow value (dilution factor from near field area to the nearest portable water intako).
The Dw value was lowered to 1M from 120, therefore, the Aij values for Table 2-2 had to be evaluated.
EVALUATIONFROM THE EG6d LETTER REVIEW OF AMENDMENT6, DATEDMAY1989 Item 9.
In Revision 5 the dilution factor for potable water, Dw, in Eq.
7 was reduced from 200 to 120.
Then, in Revision 6 the value was further reduced to 100, based on a dilution factor of 50,000 (100 times the "applicable factor" discussed in Item 2 above) from blowdown to the Richland drinking water supply.
This factor was obtained by using an average river flow of 103,810 cfs and an average blowdown flow of 1.8 cfs, plus a conservative factor of 0.87.
As noted in the discussion of Item 2 above, the 1.8 cfs average blowdown flow has been exceeded during both quarterly and annual reporting periods during commercial operation of WNP-2.
For those periods, reported calculated doses due to potable water consumption could have been too low if 'e methodology in ODCH Revision 6 had been used for the calculations.
Also, the assumed dilution factor is based on the average river flow.
Therefore, the calculated dose could have been too low for any reporting period when the river flow was less than the assumed average value.
To eliminate the reporting of doses that are too low, the methodology should use actual average blowdown and river flows for the reporting periods, maximum permitted blowdown flow and minimum river flow, or some combination of these values.
Attachment 2
TEY-11-91 May 9, 1991 Page 9 of 17 DISCUSSION OF DEFICIENCY9 INTHE ODCh:I UPDATEDTIIROUCH AMENDMENT4.
EVALUATIONFROM THE EG6cG LEITER REVIEW OF AMENDMENT6, DATEDMAY1989 (CONT.)
The Licensee's rationale for the change made by Revision 6 includes a reference to "Radiological Programs Calculation Log 88-3."
Log 88-3 should be referenced in the ODCM to comply with the intent of the last paragraph of NUREG-0133 Section 4.3. 1.
LICENSEE'S RATIONALEFOR ACHANGE MADEBYAMENDMENT7, DATEDDECEMBER 1989:
7.0 Dur1ng this reporting per1od, Amendment Ho.
7 was made to the Offs1te Dose Calculation Hanual (ODCH).
5.
Page 9; the reference to Radiological Programs Calculation Log 88-3 1s made to comply w1th the intent of HUREG-0133, Section 4.3.l as recommended by the NRC Reviewer 1n Item 9 of the Technical Evaluation Report.
Attachment 2
VEY-11-91
,,Nay 9, 1991 Page 10 of 17 DISCUSSION OF DEFICIENCY 11 INTHE ODCM UPDATEDTHROUGH AMENDMENT4.
DEFICIENCYIDENTIFIEDIN EGG-PHY-8032, DATEDMARCH 1988 In Section 2.8 of the ODCM, it is not clear why the Licensee recalculates the total allowed activity.limit for an outside temporary tank containing liquid radwaste to ensure that in the event of the'ank rupture the concentration limits will not be exceeded at the WNP-I well. It appears a simple demonstration of compliance to Technical Specification 3. 11. 1.4 could be made by multiplying the radioactivity concentration of the liquid in the tank by the volume of liquid in the tank and comparing the resultant activity to the 10 curie limit identified in the ODCM.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDEMENT6, DATEDNOVEMBER 1988:
Stand Alone Discussion As Per Tech Spec 6.14.
This stand alone discussion is included to provide a short explanation for the changes made to the WNP-2 Offsite Dose Calculation Manual (ODCM) in proposed amendment No. 6.
30.
The TER made mention of a simplified method for determining the total activity in an outside temporary storage
- tank, should such be used in support of WNP-2.
The method mentioned was to analyze the tank's radio-activity concentration and multiply it by the volume in the tank and compare the resultant activity to the 10 curie limit.
The ODCM's present methodology is an acceptable means for determining the curie limit allowed in an outside temporary storage tank.
In the event these type of tanks are put into use, then the surveillance requirement (procedure) would be established and the more simplified method mentioned could be used once the curie limit is determined based on radionuclides present in that particular temporary storage tank.
Attachment 2
TEY-11-91 Nay 9, 1991 Page ll of 17 DISCUSSION OF DEFICIENCY 11 INTHE ODCM UPDATEDTIIROUGH AMENDMENT4 EVALUATIONFROM THE EG6% LE11'ER REVIEW OF AMENDMENT6, DATEDMAY26, 1989; Item ll. In response to the suggestion that a 'simplified method be used to determine compliance with the limits of Technical Specification
- 3. 11.1.4, the Licensee stated that in the event this type of tank is put into use a simplified method could be used once the curie limit i s determined.
Technical Specification
- 3. 11. 1.4 limits the contents of radioactive material in any outside temporary tank to an amount such that a complete release would not result in a concentration at the nearest offsite water supply in excess of the 10 CFR 20 limits.
The ODCN imposes a
10 Ci limit in addition to the technical specification limit.
The current ODCH methodology requires compliance with both limits, which is more restrictive than compliance with either limit alone.
Attachment 2
TEY-11-91 May 9, 1991
'age 12 of 17 DISCUSSION OF DEFICIENCY 17 INTHE ODCM TICROUGIR AMENDMENT4.
DEFICIENCYIDENTIFIEDIN EGG-PHY-8032, DATEDMARCH 1988:
In the radiological environmental monitoring program plan there are no direct radiation monitoring locations found in the 6
9 km (3.73 - 5.59 mi) range in the NE and SE sectors nor in the 9 -
12 km (5.59 - 7.46 mi) range in the S sector as required by Technical Specification Table 3. 12-1. 1.
LICENSEE'S RATIONALEFOR A CHANGE MADEBYAMENDEMENT6, DATEDNOVEMBER 1988:
Stand Alone Discussion As Per Tech Spec 6.14.
This stand alone discussion is included to provide a short explanation for the changes made to the MNP-2 Offsite Dose Calculation Manual (ODCM) in proposed amendment No. 6.
29.
The TER listed a discrepancy in the distance from WHP-2 to some monitoring locations in support of the Radiological Environmental Monitoring Program.
This is listed as item 17 in the TER conclusion section'.
The Supply System will submit a
Technical Specification change by May 15.
1989 requesting Table 3. 12-1 have an additional footnote added.
EVALUATIONFROM THE EG6& LETTER REVIEW OF AMENDMENT6, DATEDMAY26, 1989:
Item 17.
In Revision 6 of the WNP-2 ODCN there are TLDs located in all the required sectors, but a few are slightly (up to 4%) farther from the reactor than specified by Technical Specification Table 2. 12'. 1. 1.
If four TLDs were 4% closer to the reactor the requirements of the technical specification would be satisfied exactly.
The Licensee's response
- states, "The Supply System will submit a Technical Specification change by May 15, 1989 requesting Table 3. 12-1 have an additional footnote added."
(Presumably such a footnote would permit minor deviations in location to facilitate access etc., or recognize the uncertainty in distance determination.)
(The next three pages consist of a letter from the WPPSS to the NRC giving the rationale for retaining direct radiation monitoring locations at the present locations.)