CY-19-013, Independent Spent Fuel Storage Installation - Annual Radiological Environmental Operating Report for January - December 2018
| ML19121A230 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 04/23/2019 |
| From: | Connecticut Yankee Atomic Power Co |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML19121A259 | List: |
| References | |
| CY-19-013 | |
| Download: ML19121A230 (26) | |
Text
l CY-19-013 ENCLOSURE2 HADDAMNECK INDEPENDENf SPENT FUEL STORAGE INSTALLATION ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT JANUARY - DECEMBER 2018
HADDAM NECK INDEPENDENT SPENT FUEL STORAGE INSTALLATION License Nos. DPR-61 and SFGL-21 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT January- December 2018
. t*
2fRSCS Radiation Snfoty & Con!R>I Sarvice5 April 2019 Prepared by:
Radiation Safety & Control Services 91 Portsmouth Avenue Stratham, NH 03885-2468
EXECUTIVE
SUMMARY
Connecticut Yankee's Haddam Neck facility was permanently shutdown in 1996. All fuel has been transferred into dry storage casks and placed_at the Independent Spent Fuel Storage Installation. The Radiological Environmental Monitoring Program (REMP) for the Connecticut Yankee Independent Spent Fuel Storage Installation (ISFSI) located in East Haddam, CT was continued for the period January through December 2018 in compliance with the Connecticut Y~nkee Offsite Dose Calculation Manual (ODCM).
By design, there are no liquid or gaseous effluents associated with the operation of the ISFSI. Therefore, the ODCM only requires monitoring of direct exposure from the facility. TLDs were used to measure direct gamma exposure at seven locations in the vicinity of the' ISFSI and one control location 2.8 miles away. The results of these measurements showed no significant change in exposure rates and potential doses to members of the public during the monitoring period over the baseline measurements that were collected in 2003. The results of the monitoring performed in 2018.also show that operating the Haddam Neck ISFSI results in only a small fraction of the 40 CFR Part 190 and 10 CFR Part 72.104 direct radiation dose limit of 25 mrem/year to members of the public.
CY 2018 Annual REO Report Page 2 of25
TABLE OF CONTENTS Section
1.0 INTRODUCTION
.........................................................................................6 2.0 GENERAL ISFSI AND SITE INFORMATION .............................................7 3.0 PROGRAM DESIGN ....................................................................................7 3.1 MONITORING ZONES .............................. .............................. .......................... 8 3.2 PATHWAYS MONITORED .............................. .............................. ..................... 8
3.3 DESCRIPTION
OF THE MONITORING PROGRAM .............................. ................... 8 4.0 RADIOLOGICAL DATA
SUMMARY
TABLES .........................................12 5.0 ANALYSIS OF ENVIRONMENTAL RESULTS .........................................24 5.1 SAMPLING PROGRAM DEVIATIONS .............................. .............................. .... 24 5.2 DIRECT RADIATION PATHWAY .............................. .............................. ........... 24 6.0 LAND USE CENSUS ...............................................,.,a,., *.************************* 25 7,0 REFERENCES ........................ ~ .................................................................25 CY 2018 Annual REO Report Page 3 of 25
LIST OF TABLES 3.1 Radiological Environmental Monitoring Program ................................... 9 3.2 Radiological Environmental Monitoring Locations .............................. 10 4.1 TLD Measurements By Half~Year ...........................................................13 4.2 TLD Data Summary ..................................................................................14 4.3 Direct Dose From ISFSI Operations .......................................................15
- ~
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LIST OF FIGURES Figure 3.1 Radiological Environmental Monitoring Locations .............................. 11 4.1 Annual Dose Trend at CY-1-IF ................................................................17 4.2 Annual Dose Trend at CY-6-IF ................................................................18 4.3 Annual Dose Trend at CY-48-IF ..............................................................19 4.4 Annual Dose Trend at CY-53-IF ..............................................................20 4.5 Annual Dose Trend at CY-54-IF ..............................................................21 4.6 Annual Dose Trend at CY-55-IF ..............................................................22 4.7 Annual Dose Trend at CY-56-IF ..............................................................23 CY 2018 Annual REO Report Page5 of25
1.0 INTRODUCTION
This report summarizes the findings of the Radiological Environmental Monitoring Program (REMP) conducted by Connecticut Yankee in the vicinity of the Haddam Neck Independent Spent Fuel Storage Installation. It is submitted annually in compliance with Section F of the Offsite Dose Calculation Manual (ODCM). The remainder of this report is organized as follows:
Section 2: Provides a brief description of the Connecticut Yankee site and its environs.
Section 3: Provides a description of the overall REMP design. This section includes a summary of the ODCM requirements for REMP sampling, tables listing TLD monitoring locations with compass sectors and distances from the ISFSI Pad, and maps showing the location of each of the TLD monitoring locations.
Section 4: Provides a complete set of TLD data in the exposure units of milliroentgen (mR). These TLD data are then converted to a calculated dose equivalent in units of mrem per year. This section also provides the summarized exposure rate data in the format specified by the NRC Branch Technical Position on Environmental Monitoring (Reference 1).
Section 5: Provides the results of the monitoring program. The performance of the program in meeting ODCM requirements is discussed, and the data acquired during the year is analyzed.
Section 6: Provides the status of the Land Use Census.
Section 7: References CY 2018 Annual REO Report Page6 of25
2.0 GENERAL ISFSI AND SITE INFORMATION I The Haddam Neck ISFSI site is located in the town of East Haddam, Middlesex County, Connecticut, at a point 22 miles south-southeast of Hartford, Connecticut; 25 miles northeast of New Haven, Connecticut; and 16 miles north of Long Island Sound. The site is situated on the east bank of the Connecticut River at an area known as Haddam Neck. The elevation of the site property varies from 10 to 300 feet above sea level, with the area occupied by the ISFSI Pad ranging between 45 and 50 feet above sea level.
The former plant was designed as a single unit pressurized water reactor which sustained its initial chain reaction in July 1967, with commercial operation beginning in January 1968 and a gross power output of 590 Mw(e). After 28 years of operation, the Connecticut Yankee Board of Directors voted in 1996 to permanently close and decommission the power plant. Following two years of planning and preparation, actual decommissioning began in 1998 and was completed in 2006. This site now consists of the ISFSI where the fuel from the former plant reactor is stored.
The REMP for the ISFSI began pre-operational direct radiation measurements in 2003 prior to the initial spent fuel transfer to the ISFSI. The ISFSI REMP has been in continuous operation since this transfer began.
3.0 PROGRAM DESIGN The REMP for the Haddam Neck ISFSI was designed to provide assurance to regulatory agencies and the public that the station's environmental impact is known and within anticipated limits. The direct dose limit for members of the public from operation of the ISFSI is 25 mrem per year (References 3 and 4).
The detailed sampling requirements of the REMP are given in the ODCM. The sampling requirements specified in the ODCM are summarized in Table 3.1 of this report. Details of the monitored locations are shown in Table 3.2, as well as Figure 3.1 of this report.
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3.1 Monitoring Zones The REMP is designed to allow comparison of levels of radioactivity in samples from the area possibly influenced by the ISFSI to levels found in areas not influenced by the ISFSI. The first area is called "indicator stations". The second area is called "control stations". The distinction between the two is based on relative direction from the facility and distance. Analysis of survey data from the two zones aids in_determining if there is a significant difference between the two areas. It can also help in differentiating between radioactivity or radiation due to releases and that due to other fluctuations in the environment, such as seasonal variations in the natural background.
3.2 Pathways Monitored Based on the design of the ISFSI, only the direct radiation exposure pathway is
-monitored by the REMP. This pathway is monitored by the collection of thermoluminescent dosimeters (TLDs) which are described in more detail below.
3.3 Description of the Monitoring Program 3.3.1 Direct Radiation Direct gamma radiation exposure was continuously monitored during 2018 with the use of thermoluminescent dosimeters (TLDs). At each monitoring location, these TLDs are sealed in plastic bags and attached to an object such as a tree, fence or utility pole. The TLDs are posted and retrieved on a semi.,.annual basis.
All TLDs are provided and processed by a National Voluntary Laboratory Accreditation Program (NVLAP) certified vendor. The TLDs are placed at various locations around the ISFSI. Table 3.2 lists the Station ID Codes, distances and direction of the TLDs from the ISFSI.
3.3.2 Special Monitoring Special samples are periodically taken to satisfy the ISFSI Settlement requirements. The results of these samples are available for review at the site.
A special sample was collected in 2018.
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Table 3.1 Radiological Environmental Monitoring Program Exposure Collection Analysis Pathway and/or Number of Routine Analysis Collection Analysis Sample Sample Sampling Type Frequency Frequency Media Locations Mode Direct Total Locations: 8 Continuous Semi- Gamma Semi-Radiation (7 around annual dose annual (TLD) perimeter of the site and 1 offsite control location)
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Table 3.2 Radiological Environmental Monitoring Locations Station Distance Station Description Zone* From ISFSI Direction Code From ISFSI (miles)
CY-1-IF Mouth of Discharge Canal (I}** 1 0.5 SSE CY-6-IF Substation (I)** 1 0.6 NW CY-48-IF Near Historical Met Tower Shack (I)** 1 0.4 WSW CY-53-IF lSFSI Haul Route (I)** 1 0.2 SSW CY-54-IF Rt 149 Near Mouth of Salmon River (I)** 1 1.0 ESE CY-55-IF High Voltage Tower- NW of Pad (I)** 1 0.4 NW CY-56-IF Near Historical Borrow Pit (I)** 1 0.2 E CY-10-IFC Hurd Park Road (0)** 2 2.8 NNW
Figure 3.1 Radiological Environmental Monitoring Locations Note: Indicator Location 52 was removed from the REMP in 2014.
CY 2018 Annual REO Report Page 11 of 25
4.0 RADIOLOGICAL DATA
SUMMARY
TABLES This section summarizes the analytical results of the environmental samples, which were collected during the monitoring period.
- Data from direct radiation measurements made by TLDs are presented in Table 4.1.
- The summarized TLD measurements, shown in Table 4.2, are presented*
in a format similar to that prescribed in the NRC's Radiological Assessment Branch Technical Position on Environmental Monitoring (Reference 1).
- Table 4.3 presents the estimated direct dose from ISFSI operations as determined by TLD data shown in Table 4.1 .
CY 2018 Annual REO Report Page 12 of 25
Table 4.1 TLD Measurements by Half-Year (mR)
Station ID Direction 151 Half-Year 2nd Half-Year CY-1-IF SSE 29 31 CY-6-IF NW 34 42 CY-48-IF WSW 38 41 CY-53-IF SSW 35 38 CY-54-IF ESE 32 34 CY-55-IF NW 36 40 CY-56-IF E 36 38 CY-10-IFC Control 40 41 CY-10-IFCa Control Backup 40 44 CY 2018 Annual REO Report Page 13 of 25
Table 4.2 TLD Data Summary (mR)
Indicator TLDs Indicator Station With Highest Control TLDs Mean Mean Mean Mean (Range) (Range) Station# (Range)
(No. Measurements)* (No. Measurements)* (No. Measurements)*
36.0 41.3 CY-48-IF 39.5 (29-42) (40-44) (38-41)
(14) (4) (2)
- Each "measurement" is based on semi~annual readings.
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Table 4.3 Direct Dose from ISFSI Operations (mrem) 1st Half-Year 2nd Half-Year NetTLD Calculated NetTLD Calculated Annual Station ID Result Dose Result Dose Dose CY-1-IF 0.00 0.00 0.00 0.00 0.00 CY-6-IF 0.00 0.00 0.00 0.00 0.00 CY-48-IF 0.00 0.00 0.00 0.00 0.00 CY-53-IF 0.00 0.00 0.00 0.00 0.00 CY-54-IF 0.00. 0.00 o.oo 0.00 0.00 CY-55-IF 0.00 0.00 0.00 0.00 0.00 CY-56-IF 0.00 0.00 0.00 0.00 0.00 Max Dose=> 0.00 Note:
Doses based on a 250 hour0.00289 days <br />0.0694 hours <br />4.133598e-4 weeks <br />9.5125e-5 months <br /> occupancy in both of the first and second half-years.
CY 2018 Annual REO Report Page 15 of 25
Radiological Environmental Monitoring Program Trending A series of graphs of REMP TLD data have been developed and are provided for trending purposes. The trending is developed for each of the indicator locations based on the annual historical doses. The trending is provided for the "real members of the public" based on the guidance provided in the ODCM. The analysis of the trends and associated data shows very small annual doses with minor fluctuations in the data. In this report, the uncorrected TLD results have been summarized and the annual doses, calculated for "real members of the public" based upon guidance in the ODCM, have been plotted for trending.
CY 2018 Annual REO Report Page 16 of 25 i
i I
I
Figure 4.1 Annual Dose Trend at CY-1-IF CV-1-IF 30.00 -r--------------------
25.00 ---- -------- -------
~ 20.00 m1s.oo - - - - - - - - - - - - - - - - - - -
... -+-CY-1-IF E 10.00 ---- -------- -------- -llmlt 5.00 -!---------------------
0.00 o.oo 0.00 0.00 0.09 0,01 0.14 0.00 0.00 0.00 0.00 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year Annual Doses (mrem/yr)
Location 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 CY-1-IF 0.00 0.00 0.00 0.00 0.09 0.01 0.14 0.00 0.00 0.00 0.00 CY 2018 Annual REO Report Page 17 of 25
Figure 4.2 Annual Dose Trend at CY-6-IF CV-6-IF 30.00 . . . . - - - - - - - - - - - - - - - - - - -
25.00 ; - - - - - - - - - - - - - - - - - - -
~ 20.00
~ 15.00 -t-CY-6-IF 8
10.00 ; - - - - - - - - - - - - - - - - - - _ _ , , , . - , . , - -
-nmit 5.00 +--------------------
0.01 0.00 0.00 0.00 0.00 0,03 0.05 0.00 0.00 0.00 0.00 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year Annual Doses (mrem/yr)
Location 2008 2009 201 O 2011 2012 2013 2014 2015 2016 2017 2018 CY-6-IF 0.01 0.00 0.00 0.00 0.00 0.03 0.05 0.00 0.00 0.00 0.00 CY 2018 Annual REO Report Page 18 of 25
Figure 4.3 Annual Dose Trend at CY48-IF CV-48-IF 30.00 . . . - - - - - - - - - - - - - - - - - - - - -
25.00 +--------- -----------
$. 20.00 e'a, lS.OO +-----------------_ ...--C-Y--48---IF s 10.00 + - - - - - - - - - - - - - - - - - - -..... m"""it- 11....
s.oo + --------------------
0.00 0.00 0.00 0.00 0.00 Q;OO 0.00 0.00 Q.QO 0.00 0.00 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year Annual Doses (mrem/yr)
Location 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 CY-48-IF 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CY 2018 Annual REO Report Page 19 of 25
Figure 4.4 Annual Dose Trend at CY-53-IF CY-53-IF 30.00 - , - - - - - - - - - - - - - - - - - - - -
25.00 ~ - - - - - - - - - - - - - - - - - -
.. 20.00 ------------------
~ lS.OO -+-CY-53-IF E 10.00 ----- --------- --~-.e-- -llmlt s.oo 0.29 0.09 0.62 0.50 0.38 0.05 0.22 0.00 0.00 0.03 0.00 0.00 .. "" .-..
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year
- Annual Doses (mrem/yr)
Location 200_8 2009 201 O 2011 2012 2013 2014 2015 2016 2017 2018 CY-53-IF 0.29 0.09 0.62 0.50 0.38 0.05 0.22 0.00 0.00 0.03 0.00 CY 2018 Annual REO Report Page20 of 25
Figure 4.5 Annual Dose Trend at CY-54-IF CY-54-IF 30.00 ~ - - - - - - - - - - - - - - - - - -
25.00 +----- ------- -------
.. 20.00 - - - - - - - - - - - - - - - - - - -
e'I!! 15.00 -------------------
-t-CY-54-IF E 10.00 +-------------------,-.,.--
-limit 5.00 - - - - - - - - - - - - - - - - - - - -
0.17 0.02 0.18 0.05 0.00 0.24 0,05 0.00 0.00 0.00 0.00 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year Annual Doses (mrem/yr)
Location 2008 2009 2010 2011 2012 2013 2014 2016 2016 2017 2018 CY-54-IF 0.17 0.02 0.18 0.05 0.00 0.24 0.05 0.00 0.00 0.00 0.00 CY 2018 Annual REO Report Page 21 of 25
Figure 4.6 Annual Dose Trend at CY-55-IF CY-55-IF 30.00 - . - - - - - - - - - - - - - - - - - - - - -
25.00 ---------------------
... 20.00 + - - - - - - - - - - - - - - - - - - -
~
~ lS.OO -+-CY-55-IF E 10.00 - r - - - - - - - - - - - - - - - - - - - = 1 = - i m - = - = i t -
5.00 -t-------. -------,-.-.- - - - - - -
0.38 0.32 0.29 0.23 0.48 ();19 Q.48 0.00 0.00 0.00 0.00 0.00 ..J-,~.l"""'I...............:~-~~,.....:....-:""""',,....~.......~;.
............~--;..-.
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Year Annual Doses (mrem/yr)
Location 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 CY-55-IF 0.38 0.32 0.29 0.23 0.48 0.19 0.48 0.00 0.00 0.00 0.00 CY 2018 Annual REO Report Page 22 of 25
Figure 4.7 Annual Dose Trend at CY-56~1F cv.. s6-IF 30.00 ~ - - - - - - ~ - - - - - - - - - - -
25.00 ---- -------- -------
._ 20.00 -t--------------------
~
15.00
-t-CY-56-JF E 10.00 - - - - - - - - - - - - - - --nmlt ----
5.00 -t---..-- --------- ---------
0.17 0.37 0.27 0.02 0.11 0.26 0.15 0.09 0.00 0.09 0.00 o.oo* ~.1"""'41:.....-t---i:P"""IIII;.~~~.._~~......._ ..~~.-4~1111-,.~;--~.--.L
..J...-<...
2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Vear Annual Doses (mrem/yr)
Location 2008 2009 2010 . 2011 2012 2013 2014 2016 2016 2017 2018 CY-56-IF 0.17 0.37 0.27 0.02 0.11 0.26 0.15 0.09 0.00 0.09 0.00 CY 2018 Annual REO Report Page23 of 25
5.0 ANALYSIS OF ENVIRONMENTAL RESULTS 5.1 Sampling Program Deviations A sampling program deviation is defined as samples that are unobtainable due to hazardous conditions or to malfunction of sampling equipment. Such deviations do not compromise the program's effectiveness and in fact are considered insignificant with respect to what is normally anticipated for this Radiological Environmental Monitoring Program.
There were two deviations of the sampling program documented in 2018.
- 1. A review of completed 2017 REMP TLD forms found several administrative errors. These errors were incorrect signatures on the forms and missing TLD changeout times. The signature issue occurred as a result of completing new forms for legibility purposes. The new forms, however, were not signed by the actual task performer. The forms also require a changeout time to be recorded. These conditions have no impact on the REMP.
- 2. A transposition error was identified during a review of the 2017 second~half REMP TLD dose calculation form. This error was corrected prior to issuing the Annual REO report for 2017. This condition has no impact on the REMP.
5.2 Direct Radiation Pathway 5.2.1 Annual Dose Trends Direct radiation is continuously measured at 7 indicator locations surrounding the Haddam Neck ISFSI, along with 1 control location (Hurd Park Road) using thermoluminescent dosimeters (TLDs). These dosimeters are collected every six months for readout at the NVLAP certified dosimetry services vendor.
Review of the data in Figures 4.1 through 4. 7 shows no significant difference in annual doses over time at the indicator locations and their relation to the 25 m rem/yr limit.
5.2.2 Direct Doses from ISFSI Operations The ODCM specifies that a cumulative dose estimate from direct radiation is required to be determined semi-annually. This dose estimate is the potential CY 2018 Annual REO Report Page24 of 25
dose to any real member of the public that could use portions of the site or be present adjacent to the site for recreational activities throughout the year. The ODCM states that direct exposure above background can be estimated by subtracting the average TLD value of the control station from the indicator location measurements. As in previous years, the 2018 dose estimate assumes a total of 500 hours0.00579 days <br />0.139 hours <br />8.267196e-4 weeks <br />1.9025e-4 months <br /> occupancy for the dose calculation; of which 250 hours0.00289 days <br />0.0694 hours <br />4.133598e-4 weeks <br />9.5125e-5 months <br /> are used in both the first and second half-years. The most likely location for exposure to a member of the public from the ISFSI is either along the discharge canal or the Connecticut or Salmon Rivers for boating and fishing; however, the time estimates are conservatively applied to all monitoring locations.
Table 4.3 presents the results of the dose calculations. All doses are 0.00 mrem.
6.0 LAND USE CENSUS The most recent census remained in effect for 2018; therefore, no changes were made to the monitoring program.
7.0 REFERENCES
- 1. USNRC Radiological Assessment Branch Technical Position, "An Acceptable Radiological Environmental Monitoring Program," Revision 1, November 1979.
- 2. Haddam Neck Offsite Dose Calculation Manual, Revision 25.
- 3. 40 CFR Part 190, "Environmental Radiation Protection Standards for Nuclear Power Operation".
- 4. 10 CFR Part 72.104, "Criteria for Radioactive Materials in Effluents and Direct Radiation from an ISFSI or MRS".