CY-16-018, ISFSI - Annual Radiological Environmental Operating Report, January - December 2015
| ML16120A377 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 12/31/2015 |
| From: | Radiation Safety & Control Services |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML16120A368 | List: |
| References | |
| CY-16-018 | |
| Download: ML16120A377 (26) | |
Text
CY-16-018 ENCLOSURE2
. } *,:--..
, :-'~:- _ HADDAM NECK INP:S:r~~DENT SPENT F~L STORAGE INSTALLATION ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT JANUARY - DECEMBER 2015
HADDAM NECK INDEPENDENT SPENT FUEL STORAGE INSTALLATION License Nos. DPR-61 and SFGL-21 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT January - December 2015 RSCS Radiat.o Safety & Control Services April 2016 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 2015 in compliance with the Connecticut Yankee 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 2015 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 2015 Annual REO Report Page 2of25
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 .................................................................................25
7.0 REFERENCES
..........................................................................................25 CY 2015 Annual REO Report Page 3of25
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 lsfsi Operations .........................................................15 CY 2015 Annual REO Report Page 4of25
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 2015 Annual REO Report Page 5of25
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 showing measured results (mR) and calculated doses (mrem per year). This section also provides the summarized exposure rate data in the format specified by the NRG 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 2015 Annual REO Report Page 6 of 25
2.0 GENERAL ISFSI AND SITE INFORMATION 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 (anging 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 Independent Spent Fuel Storage Installation where the fuel from the former plant reactor is stored.
The Radiological Environmental Monitoring Program (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 Radiological Environmental Monitoring Program (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.
CY 2015 Annual REO Report Page 7of25
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 2015 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 Independent Spent Fuel Storage Installation (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. For this monitoring period, no special samples were collected as part of the Connecticut Yankee ISFSI Radiological Environmental Monitoring Program.
CY 2015 Annual REO Report Page 8of25
Table 3.1 Radiological Environmental Monitoring Program Exposure Collection Analysis Pathway and/or Number of Routine Analysis Analysis Collection 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)
CY 2015 Annual REO Report Page 9of25
Table 3.2 Radiological Environmental Monitoring Locations Distance Station Direction Station Description Zone* From ISFSI 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 ISFSI 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 2015 Annual REO Report Page 11of25
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 2015 Annual REO Report Page 12 of 25
Table 4.1 TLD Measurements by HalfAYear (mR) 51 Station ID Direction 1 Half-Year 2"a Half-Year CY-1-IF SSE 30 34 CY-6-IF NW 32 28 CY-48-IF WSW 31 33 CY-53-IF SSW 34 34 CY-54-IF ESE 32 35 CY-55-IF NW 32 36 CY-56-IF E 33 38 CY-10-IFC Control 34 36 CY-10-IFCa Control Backup 36 37 CY 2015 Annual REO Report Page 13 of 25
Table 4.2 TLD Data Summary (mR)
Indicator Station With Highest Indicator TLDs Control TLDs Mean Mean Mean Mean (Range) (Range) Station# (Range)
(No. Measurements)* (No. Measurements)* (No. Measurements)*
33 35.8 CY-56-IF 35.5 (28 -38) (34- 37) (33-38)
(14) (4) (2)
- Each "measurement" is based on semi-annual readings.
CY 2015 Annual REO Report Page 14 of 25
Table 4.3 Direct Dose from ISFSI Operations (mrem) 1st Half-Year 2"d 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 0.00 0.00 0.00 CY-55-IF 0.00 0.00 0.00 0.00 0.00 CY-56-IF 0.00 0.00 1.50 0.09 0.09 Max Dose=> 0.09 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 2015 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 2015 Annual REO Report Page 16of25
Figure 4.1 Annual Dose Trend at CY-1-IF CV-1-IF 30.00 ~-------------------
25 .00 +--------------------
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 - i - - - - - - - - - - - - - - - - - - - -
... -+- CY-1-IF E 10.00 -+------------------- -~1-i m-it-5.00 - i - - - - - - - - - - - - - - - - - - - -
0 .00 0.00 0.00 0.00 0.00 0 .09 0.01 0 .14 0 .00 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses {mrem/yr)
I Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 I CY-1-IF 0.00 0.00 0.00 0.00 0.00 0.09 0.01 0.14 0.00 CY 2015 Annual REO Report Page 17 of 25
Figure 4.2 Annual Dose Trend at CY-6-IF CY-6-IF 30.00 - - y - - - - - - - - - - - - - - - - - - - -
25.00 -t-~------------------
... 20.00 - + - - - - - - - - - - - - - - - - -- ---
~ 15.00 +-- - - - - - - - - - - - - - - - - - -
-+- CY-6-IF E 10.00 - limit 5.00 0.15 0.01 0.00 0.00 0.00 0 .00 0.03 0.05 0.00 0.00
.... . . . . . . ~ .
.... I 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-6-IF 0 .15 0.01 0.00 0.00 0.00 0.00 0.03 0.05 0.00 CY 2015 Annual REO Report Page 18 of 25
Figure 4.3 Annual Dose Trend at CY-48-IF CY-48-IF 30.00 ~-------------------
25 .00 +--------------------
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
....>~ 15.00 -+--------------------
... CY-48-IF E 10.00
- lim it 5.00 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0 .00 0.00
~ ..... ..... ..... ..... ..... ..... ..... .....
0.00 T 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-48-IF 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CY 2015 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 - + - - - - - - - - - - - - - - - - - - - - - -
~ 15 .00 + - - - - - - - - - - - - - - - - - - - -
-+- CY-53-IF E10.00 ..,.___ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __
- limit 5.00 - < - - - - - - - - - - - - - - - - - - - -
0.50 0.29 0.09 0.62 0.50 0.38 0.05 0 .22 0.00
~
~
~
~ ~
2007 2008 2009 2010 2011 201 2 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 201 O 2011 2012 2013 2014 2015 CY-53-IF 0.50 0.29 0.09 0.62 0.50 0.38 0.05 0.22 0.00 CY 2015 Annual REO Report Page 20of25
Figure 4.5 Annual Dose Trend at CY-54-IF CY-54-IF 30.00 - r - - - - - - - - - - - - - - - - - - - -
25 .00 +-~------------------
... 20.00 + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 - + - - - - - - - - - - - - - - - - - - - - -
-+- CY-54-I F E 10.00 +-------------------,.-------,-
- limit 5.00 - + - - - - - - - - - - - - - - - - - - - - -
0.19 0.17 0.02 0 .18 0.05 0.00 0.24 0.05 0.00
~ &
T T T .... '
2007 2008 2009 2010 2011 2012 2013 2014 2015 Vear Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-54-IF 0.19 0.17 0.02 0.18 0.05 0.00 0.24 0.05 0.00 CY 2015 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 + - - - - - - - - - - - - - - - - - - - - - -
~ 15.00 +-- - - - - - - - - - - - - - - - - - -
.... -+-CY-55-IF E 10.00
- limit 5.00 0.60 0.38 0.32 0.29 0.23 0.48 0.19 0.48 0.00
~ ~ ~ ~
A .... A .... ~
0.00 ~ I ~ .....
2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-55-IF 0.60 0.38 0.32 0.29 0.23 0.48 0.19 0.48 0.00 CY 2015 Annual REO Report Page 22 of 25
Figure 4. 7 Annual Dose Trend at CY-56-IF CY IF 30.00 ~-------------------
25 .00 -+--------------------~
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 + - - - - - - - - - - - - - - - - - - - -
... ...-cv-56-I F E 10.00 +-----------------~~-
- limit 5.00 + - - - - - - - - - - - - -- - -- - - - -
0.47 0.1 7 0.37 0.27 0.02 0.11 0.26 0 .15 0.09 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-56-IF 0.47 0.17 0.37 0.27 0.02 0.11 0.26 0.15 0.09 CY 2015 Annual REO Report Page 23 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 no deviations of the sampling program in 2015.
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 mrem/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 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 2015 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.
CY 2015 Annual REO Report Page 24of25
Table 4.3 presents the results of the dose calculations. The highest calculated dose is at location Station ID number CY-56-IF. The maximum calculated annual dose at that location is 0.09 mrem. This value is less than 1 percent of the 25 mrem per year limit.
6.0 LAND USE CENSUS The most recent census remained in effect for 2015; 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".
CY 2015 Annual REO Report Page 25of25
CY-16-018 ENCLOSURE2
. } *,:--..
, :-'~:- _ HADDAM NECK INP:S:r~~DENT SPENT F~L STORAGE INSTALLATION ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT JANUARY - DECEMBER 2015
HADDAM NECK INDEPENDENT SPENT FUEL STORAGE INSTALLATION License Nos. DPR-61 and SFGL-21 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT January - December 2015 RSCS Radiat.o Safety & Control Services April 2016 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 2015 in compliance with the Connecticut Yankee 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 2015 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 2015 Annual REO Report Page 2of25
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 .................................................................................25
7.0 REFERENCES
..........................................................................................25 CY 2015 Annual REO Report Page 3of25
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 lsfsi Operations .........................................................15 CY 2015 Annual REO Report Page 4of25
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 2015 Annual REO Report Page 5of25
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 showing measured results (mR) and calculated doses (mrem per year). This section also provides the summarized exposure rate data in the format specified by the NRG 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 2015 Annual REO Report Page 6 of 25
2.0 GENERAL ISFSI AND SITE INFORMATION 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 (anging 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 Independent Spent Fuel Storage Installation where the fuel from the former plant reactor is stored.
The Radiological Environmental Monitoring Program (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 Radiological Environmental Monitoring Program (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.
CY 2015 Annual REO Report Page 7of25
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 2015 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 Independent Spent Fuel Storage Installation (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. For this monitoring period, no special samples were collected as part of the Connecticut Yankee ISFSI Radiological Environmental Monitoring Program.
CY 2015 Annual REO Report Page 8of25
Table 3.1 Radiological Environmental Monitoring Program Exposure Collection Analysis Pathway and/or Number of Routine Analysis Analysis Collection 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)
CY 2015 Annual REO Report Page 9of25
Table 3.2 Radiological Environmental Monitoring Locations Distance Station Direction Station Description Zone* From ISFSI 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 ISFSI 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.
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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 2015 Annual REO Report Page 12 of 25
Table 4.1 TLD Measurements by HalfAYear (mR) 51 Station ID Direction 1 Half-Year 2"a Half-Year CY-1-IF SSE 30 34 CY-6-IF NW 32 28 CY-48-IF WSW 31 33 CY-53-IF SSW 34 34 CY-54-IF ESE 32 35 CY-55-IF NW 32 36 CY-56-IF E 33 38 CY-10-IFC Control 34 36 CY-10-IFCa Control Backup 36 37 CY 2015 Annual REO Report Page 13 of 25
Table 4.2 TLD Data Summary (mR)
Indicator Station With Highest Indicator TLDs Control TLDs Mean Mean Mean Mean (Range) (Range) Station# (Range)
(No. Measurements)* (No. Measurements)* (No. Measurements)*
33 35.8 CY-56-IF 35.5 (28 -38) (34- 37) (33-38)
(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 2"d 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 0.00 0.00 0.00 CY-55-IF 0.00 0.00 0.00 0.00 0.00 CY-56-IF 0.00 0.00 1.50 0.09 0.09 Max Dose=> 0.09 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 2015 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 2015 Annual REO Report Page 16of25
Figure 4.1 Annual Dose Trend at CY-1-IF CV-1-IF 30.00 ~-------------------
25 .00 +--------------------
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 - i - - - - - - - - - - - - - - - - - - - -
... -+- CY-1-IF E 10.00 -+------------------- -~1-i m-it-5.00 - i - - - - - - - - - - - - - - - - - - - -
0 .00 0.00 0.00 0.00 0.00 0 .09 0.01 0 .14 0 .00 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses {mrem/yr)
I Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 I CY-1-IF 0.00 0.00 0.00 0.00 0.00 0.09 0.01 0.14 0.00 CY 2015 Annual REO Report Page 17 of 25
Figure 4.2 Annual Dose Trend at CY-6-IF CY-6-IF 30.00 - - y - - - - - - - - - - - - - - - - - - - -
25.00 -t-~------------------
... 20.00 - + - - - - - - - - - - - - - - - - -- ---
~ 15.00 +-- - - - - - - - - - - - - - - - - - -
-+- CY-6-IF E 10.00 - limit 5.00 0.15 0.01 0.00 0.00 0.00 0 .00 0.03 0.05 0.00 0.00
.... . . . . . . ~ .
.... I 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-6-IF 0 .15 0.01 0.00 0.00 0.00 0.00 0.03 0.05 0.00 CY 2015 Annual REO Report Page 18 of 25
Figure 4.3 Annual Dose Trend at CY-48-IF CY-48-IF 30.00 ~-------------------
25 .00 +--------------------
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
....>~ 15.00 -+--------------------
... CY-48-IF E 10.00
- lim it 5.00 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0 .00 0.00
~ ..... ..... ..... ..... ..... ..... ..... .....
0.00 T 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-48-IF 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CY 2015 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 - + - - - - - - - - - - - - - - - - - - - - - -
~ 15 .00 + - - - - - - - - - - - - - - - - - - - -
-+- CY-53-IF E10.00 ..,.___ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __
- limit 5.00 - < - - - - - - - - - - - - - - - - - - - -
0.50 0.29 0.09 0.62 0.50 0.38 0.05 0 .22 0.00
~
~
~
~ ~
2007 2008 2009 2010 2011 201 2 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 201 O 2011 2012 2013 2014 2015 CY-53-IF 0.50 0.29 0.09 0.62 0.50 0.38 0.05 0.22 0.00 CY 2015 Annual REO Report Page 20of25
Figure 4.5 Annual Dose Trend at CY-54-IF CY-54-IF 30.00 - r - - - - - - - - - - - - - - - - - - - -
25 .00 +-~------------------
... 20.00 + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 - + - - - - - - - - - - - - - - - - - - - - -
-+- CY-54-I F E 10.00 +-------------------,.-------,-
- limit 5.00 - + - - - - - - - - - - - - - - - - - - - - -
0.19 0.17 0.02 0 .18 0.05 0.00 0.24 0.05 0.00
~ &
T T T .... '
2007 2008 2009 2010 2011 2012 2013 2014 2015 Vear Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-54-IF 0.19 0.17 0.02 0.18 0.05 0.00 0.24 0.05 0.00 CY 2015 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 + - - - - - - - - - - - - - - - - - - - - - -
~ 15.00 +-- - - - - - - - - - - - - - - - - - -
.... -+-CY-55-IF E 10.00
- limit 5.00 0.60 0.38 0.32 0.29 0.23 0.48 0.19 0.48 0.00
~ ~ ~ ~
A .... A .... ~
0.00 ~ I ~ .....
2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-55-IF 0.60 0.38 0.32 0.29 0.23 0.48 0.19 0.48 0.00 CY 2015 Annual REO Report Page 22 of 25
Figure 4. 7 Annual Dose Trend at CY-56-IF CY IF 30.00 ~-------------------
25 .00 -+--------------------~
... 20.00 - + - - - - - - - - - - - - - - - - - - - - -
~ 15.00 + - - - - - - - - - - - - - - - - - - - -
... ...-cv-56-I F E 10.00 +-----------------~~-
- limit 5.00 + - - - - - - - - - - - - -- - -- - - - -
0.47 0.1 7 0.37 0.27 0.02 0.11 0.26 0 .15 0.09 2007 2008 2009 2010 2011 2012 2013 2014 2015 Year Annual Doses (mrem/yr)
Location 2007 2008 2009 2010 2011 2012 2013 2014 2015 CY-56-IF 0.47 0.17 0.37 0.27 0.02 0.11 0.26 0.15 0.09 CY 2015 Annual REO Report Page 23 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 no deviations of the sampling program in 2015.
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 mrem/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 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 2015 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.
CY 2015 Annual REO Report Page 24of25
Table 4.3 presents the results of the dose calculations. The highest calculated dose is at location Station ID number CY-56-IF. The maximum calculated annual dose at that location is 0.09 mrem. This value is less than 1 percent of the 25 mrem per year limit.
6.0 LAND USE CENSUS The most recent census remained in effect for 2015; 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".