DISTRIBUTION

Email distribution to:

1. Environment Agency Site Inspector2. Head of Radiological Protection and Research Management, Food Standards Agency3. Head of Profession-Environment and Waste

Original report to be filed in Dosimetry Office.

ENVIRONMENTAL MONITORING PROGRAMME RESULTS 2nd QUARTER 2015

C O N T E N T S SECTION TITLE PAGE NO 1. PURPOSE 1 2. SCOPE 1 3. RESPONSIBILITIES 1 4. PROCEDURE 1 5. NOTEWORTHY RESULTS 3 6. DEFINITIONS 3 7. REFERENCES 3 8. RECORDS 3 Appendix A Terrestrial Programme: Environmental TLD Results Appendix B Terrestrial Programme: Environmental Gamma Doserates Appendix C Terrestrial Programme: Passive Shade Gamma Activity Analysis Appendix D Terrestrial Programme: Milk Activity Analysis Appendix E Terrestrial Programme: Herbage Activity Analysis Appendix F Marine Programme: Beach Gamma Doserate Monitoring Appendix G Marine Programme: Marine Samples Activity Analysis Appendix H Strandline monitoring results

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ENVIRONMENTAL MONITORING PROGRAMME RESULTS 2nd QUARTER 2015

1. PURPOSE

This report provides the results of the programme of environmental monitoring for radioactivity around the Wylfa site, to ensure compliance with the conditions within the Environmental Permit (ref. 1) issued by the Environment Agency (EA) for Wylfa Power Station under the Environmental Permitting (England & Wales) Regulations 2010.

2. SCOPE

This report covers all statutory environmental monitoring identified by the Environment Agency in the Compilation of Environment Agency Requirements, Approvals and Specifications (CEARAS) (ref. 2), for the 2nd Quarter 2015.

3. RESPONSIBILITIES 3.1 The Head of Health Physics and Chemistry is responsible for reviewing and authorising this

report and for the provision of expert advice on the monitoring of radioactivity in the vicinity of the Wylfa site.

4. PROCEDURE

All environmental monitoring was carried out in accordance with the procedures listed in the Wylfa Power Station Health Physics Departmental Instruction WYA/RHI/017/005 “Management of the Environmental Monitoring Programme” (ref. 3). All reasonably practicable measures have been taken to achieve the detection limits specified in the CEARAS. Unless otherwise noted, all positive results (i.e. those exceeding the detection limit) are quoted with uncertainties at the 95% confidence level based upon counting statistics only. Where results are less than, or equal to, the detection limit, the detection limit value has been reported. If any result has exceeded the mean of the previous 12 results plus 3 standard deviations then this will be noted in the “remarks” column of a particular sample, and, as far as reasonably practicable, an explanation provided for any such value. Analysis is carried out locally at the station or at a Contract Laboratory. All analytical methods are validated and controlled in a manner consistent with the requirements of ISO 17025 that are specified in the CEARAS.

4.1 Terrestrial Environmental Monitoring Programme

The terrestrial programme includes measurements of radiation dose rates over pasture, radiation doses at the site perimeter fence and at set distances from the station, passive shade deposition collectors, grass samples, soil cores and milk samples.

4.1.1 TLDs are deployed quarterly at locations on the perimeter fence with one TLD per 30°

sector, and in three arcs around Wylfa; at approx 5, 10 and 30 km distances with at least one per 30° sector. Exposed TLDs are sent to the Approved Dosimetry Service for processing and analysis. The results are listed in Appendix A.

4.1.2 Quarterly doserate measurements are carried out using a Mini 6-80/MC70 at 9 or more

inner (3km) locations, and 9 or more outer (10km) locations. The dose rate (nGy/hr) is a measurement of air kerma rate in the environment due to natural terrestrial

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radioactivity, cosmic contribution, inherent instrument background and man-made sources (WYA/RHI/017/005 (ref. 3) and TGN-M5 refer (ref. 4)). The results are listed in Appendix B (Environmental Gamma Doserate measurements).

4.1.3 Passive shades are deployed at eight sites (two shades per site) in two arcs at

approximately 1km and 10km. The shades are collected monthly and analysed by Gamma Spectrometry at Wylfa. The results are listed in Appendix C.

4.1.4 A sample of milk is collected from each farm on a quarterly basis. The samples are then

analysed by gamma spectrometry at Wylfa. Quarterly samples are bulked to give Inner (farms 1,3 & 4) and Outer (farms 5-8) quarterly samples which are sent to the Contract Laboratory for quarterly Sulphur 35 analysis and annual Carbon 14 analysis (to be completed in Quarter 2). The results are listed in Appendix D.

4.1.5 Grass (herbage) samples are collected from the inner four farm sites and Wylfa Head

(the nearest site to the station) once per quarter and are analysed by gamma spectrometry. The Nearest Location sample, and bulked Inner Farms sample are forwarded to the Contract Laboratory, where quarterly Sulphur-35 measurements and annual Carbon-14 measurements are taken. The results are listed in Appendix E.

4.1.6 Soil cores are collected from one of the herbage locations once per annum, and are

analysed by gamma spectrometry and for gross beta activity. The results will be reported in quarter 3 2015.

4.2 Marine Environmental Monitoring Programme

The marine programme includes measurements of radiation dose rates over shoreline or sediment, measurements of contamination of fishing equipment and the beach and analysis of seaweed, sediment, fish, crustacean, and mollusc samples.

4.2.1 Quarterly spot gamma radiation dose rates were measured at 5 or more Beach sites (as

evenly spaced as far as practicable, with at least two locations either side of the station). The results are listed in Appendix F.

4.2.2 Marine sediment samples are collected quarterly and are analysed by gamma

spectrometry and for gross beta activity. The results are listed in Appendix G. 4.2.3 Seaweed, Fish, crustacean and mollusc samples are collected from local fishermen on a

quarterly basis, when available, and are analysed by gamma spectrometry and for gross beta activity. The results are listed in Appendix G.

4.2.4 Six monthly contamination surveys of the strandline at Porth yr Ogof are conducted

using portable contamination monitors. These results are reported Appendix H.

4.2.5 Annual contamination monitoring of fishing equipment used by local fishermen is carried out using a contamination probe and ratemeter. The results will be reported in the 3rd or 4th quarter 2015.

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5. NOTEWORTHY RESULTS

Environmental TLDs The Harshaw TLD results are generally higher than the Vinten TLD results (as expected and discussed in the Commissioning Report) so if a statistical test is carried out against the previous 12 results of the Vinten TLDs many will exceed the mean plus 3 standard deviations, or the mean plus 4 standard deviations, of the previous 12 Vinten results. This has been discussed separately with the Environment Agency as in Quarter 3 only the Harshaw TLD will be used.

Beach Gamma Doserates The doserates at the beaches continue to be at an elevated level due to the instrument used giving readings approximately 25% higher than an alternative instrument used for comparison. This was not discovered until after the Q2 2015 surveys were completed. None of the results exceeded any statistical tests this quarter. An alternative instrument will be used for the surveys in Q3.

This is also true for the Environmental Gamma Doserates though in Q1 this effect was less noticeable due to the greater variation in dose rates over pasture which resulted in only one measurement exceeding the mean plus 3 standard deviations of the previous 12 results.

Marine The Caesium-137 and Potassium-40 activity in the sample of lobster exceeded the mean plus 4 standard deviations of the previous 12 results. These were not notified to the Environment Agency at the time of discovery as the Cs-137 result was below the Minimum Detectable Activity (<MDA) and was below the minimum detection limit specified in the CEARAS, and the K-40 is a naturally occurring nuclide and therefore not reported as previously agreed.

6. DEFINITIONS

Where “N/A” is noted under results, it indicates that the quantity is “not applicable” for the sampletype or not required to be performed in this quarter (“not assessed”).

Where “N/S” is noted under results, no sample was available from the location or for the sample type.

7. REFERENCES

1. Environment Agency Environmental Permit Number EPR/GB3235DL/V0012. Compilation of Environment Agency Requirements, Approvals and Specifications (made under

Permit number EPR/GB3235DL/V001) Issue 1.3. WYA/RHI/017/005 – “Management of the Environmental Monitoring Programme”.4. Routine Measurement of Gamma Ray Air Kerma Rate in the Environment - Technical Guidance

Note (Monitoring) M5, HMIP, September 1995.

8. RECORDS

This Technical Report is the statutory record of environmental monitoring results.

Site Exposure Exposure Exposure Exposure Exposure Exposure Exposure Start End Period (µSv) (µSv/day) (µSv) (µSv/day)

W1 18/04/2015 25/07/2015 98.00 315.02 3.21 206.40 2.11W2 18/04/2015 25/07/2015 98.00 155.88 1.59 200.39 2.04W3 18/04/2015 25/07/2015 98.00 144.78 1.48 206.50 2.11W4 18/04/2015 25/07/2015 98.00 200.40 2.04 222.71 2.27W5 18/04/2015 25/07/2015 98.00 - - 212.94 2.17W6 18/04/2015 25/07/2015 98.00 127.67 1.30 224.81 2.29W7 18/04/2015 25/07/2015 98.00 175.84 1.79 213.98 2.18W8 18/04/2015 25/07/2015 98.00 146.13 1.49 208.58 2.13W9 18/04/2015 25/07/2015 98.00 171.77 1.75 261.08 2.66W10 18/04/2015 25/07/2015 98.00 176.95 1.81 245.01 2.50W11 18/04/2015 25/07/2015 98.00 173.13 1.77 224.75 2.29W12 18/04/2015 25/07/2015 98.00 113.42 1.16 206.74 2.11W13 18/04/2015 25/07/2015 98.00 217.97 2.22 251.72 2.57W14 18/04/2015 25/07/2015 98.00 121.22 1.24 264.10 2.69W15 18/04/2015 28/07/2015 101.00 214.97 2.13 221.50 2.26 *W16 18/04/2015 25/07/2015 98.00 194.98 1.99 242.63 2.48W17 18/04/2015 28/07/2015 101.00 153.72 1.52 - -W18 18/04/2015 25/07/2015 98.00 255.61 2.61 243.89 2.49W19 18/04/2015 25/07/2015 98.00 221.47 2.26 270.72 2.76W20 19/04/2015 26/07/2015 98.00 176.76 1.80 278.74 2.84W21 19/04/2015 26/07/2015 98.00 219.49 2.24 259.51 2.65W22 19/04/2015 26/07/2015 98.00 225.92 2.31 233.69 2.38W23 19/04/2015 26/07/2015 98.00 271.17 2.77 192.04 1.96W24 19/04/2015 26/07/2015 98.00 133.63 1.36 220.31 2.25W25 19/04/2015 26/07/2015 98.00 159.65 1.63 243.82 2.49W26 19/04/2015 26/07/2015 98.00 204.56 2.09 249.61 2.55W27 19/04/2015 26/07/2015 98.00 205.97 2.10 281.11 2.87W28 19/04/2015 26/07/2015 98.00 113.63 1.16 222.05 2.27W29 19/04/2015 26/07/2015 98.00 173.10 1.77 260.75 2.66W30 19/04/2015 26/07/2015 98.00 186.18 1.90 275.55 2.81W31 19/04/2015 26/07/2015 98.00 152.15 1.55 262.84 2.68W32 19/04/2015 26/07/2015 98.00 214.25 2.19 246.13 2.51W33 19/04/2015 26/07/2015 98.00 265.62 2.71 287.66 2.94W34 19/04/2015 26/07/2015 98.00 207.53 2.12 254.24 2.59W35 18/04/2015 25/07/2015 98.00 288.30 2.94 294.02 3.00W36 19/04/2015 26/07/2015 98.00 134.31 1.37 278.11 2.84W37 18/04/2015 25/07/2015 98.00 196.37 2.00 254.60 2.60W38 18/04/2015 25/07/2015 98.00 184.24 1.88 232.71 2.37W39 18/04/2015 25/07/2015 98.00 170.08 1.74 210.13 2.14W40 19/04/2015 26/07/2015 98.00 183.57 1.87 224.82 2.29W41 18/04/2015 25/07/2015 98.00 219.12 2.24 246.29 2.51W42 18/04/2015 25/07/2015 98.00 167.81 1.71 224.49 2.29W43 18/04/2015 25/07/2015 98.00 242.40 2.47 296.78 3.03W44 18/04/2015 25/07/2015 98.00 206.06 2.10 257.02 2.62

Harshaw

APPENDIX A

ENVIRONMENTAL TLD RESULTSSecond Quarter 2015

Vinten

Site Exposure Exposure Exposure Exposure Exposure Exposure Exposure Start End Period (µSv) (µSv/day) (µSv) (µSv/day)

F1 18/04/2015 25/07/2015 98.00 174.14 1.78 270.19 2.76F2 18/04/2015 25/07/2015 98.00 157.53 1.61 250.32 2.55F3 18/04/2015 25/07/2015 98.00 198.71 2.03 241.95 2.47F4 18/04/2015 25/07/2015 98.00 158.54 1.62 287.04 2.93F5 18/04/2015 25/07/2015 98.00 171.52 1.75 217.76 2.22F6 18/04/2015 25/07/2015 98.00 177.10 1.81 300.13 3.06F7 18/04/2015 25/07/2015 98.00 223.52 2.28 320.17 3.27F8 18/04/2015 25/07/2015 98.00 245.28 2.50 333.60 3.40F9 18/04/2015 25/07/2015 98.00 175.44 1.79 265.12 2.71F10 18/04/2015 25/07/2015 98.00 212.16 2.16 268.87 2.74F11 18/04/2015 25/07/2015 98.00 226.87 2.31 302.34 3.09F12 18/04/2015 25/07/2015 98.00 176.53 1.80 264.54 2.70

Remarks:Both Vinten (old type) and Harshaw (new type) TLD results are shown.

* The Harshaw TLD at location W15 was changed 3 days earlier than the Vinten so the Exposure period was 98 days. This has beentaken into account in calculating the exposure per day result.

Site W17 Harshaw TLD was missing at the time of collection. It appeared to have been deliberatly removed by persons unknown,and was subsequently found and returned to the Power Station. It was not assessed due to lack of knowledge of its whereabouts whilst missing.Site W5 Vinten TLD was also missing at the time of collection.

The Harshaw TLD results are generally higher than the Vinten TLD results (as expected and discussed in the Commissioning Report)so if a statistical test is carried out against the previous 12 results of the Vinten TLDs many will exceed the mean plus 3 standarddeviations, or the mean plus 4 standard deviations, of the previous 12 Vinten results. This has been discussed separately with the Environment Agency as in Quarter 3 onwards only the Harshaw TLD will be used.

Vinten Harshaw

APPENDIX A Continued

ENVIRONMENTAL TLD RESULTSSecond Quarter 2015

600 SEC INNER GRID REF. DATE

COUNT GROSS NET Annual Mean

970 1 354945 03-Jun-15 83.8 32.0 ***** *** - ***

987 2 358944 03-Jun-15 85.2 33.4 ***** *** - ***

1015 3 361939 03-Jun-15 87.7 35.8 ***** *** - ***

1028 4 362936 03-Jun-15 88.8 37.0 ***** *** - ***

1067 5 358932 29-Apr-15 92.1 40.3 ***** *** - ***

1099 6 353930 29-Apr-15 94.9 43.1 ***** *** - ***

1119 7 350928 29-Apr-15 96.6 44.8 ***** *** - ***

1126 8 343930 29-Apr-15 97.2 45.4 ***** *** - ***

1118 9 343934 03-Jun-15 96.5 44.7 ***** *** - ***

1142 10 349939 03-Jun-15 98.6 46.8 ***** *** - ***

1154 11 350943 03-Jun-15 99.7 47.8 ***** *** - ***

1163 12 350942 13-May-15 100.4 48.6 ***** *** - ***

OUTER

1127 13 425945 04-Jun-15 97.3 45.5 ***** *** - ***

1138 14 425931 04-Jun-15 98.3 46.5 ***** *** - ***

1107 15 419902 04-Jun-15 95.6 43.8 ***** *** - ***

1148 16 412895 04-Jun-15 99.1 47.3 ***** *** - ***

1195 17 392875 05-Jun-15 103.2 51.4 ***** *** - ***

1204 18 382867 05-Jun-15 104.0 52.2 ***** *** - ***

1219 19 354858 17-Jun-15 105.3 53.5 ***** *** - ***

1237 20 347858 17-Jun-15 106.8 55.0 ***** *** - ***

1205 21 327864 17-Jun-15 104.1 52.2 ***** *** - ***

1193 22 313866 17-Jun-15 103.0 51.2 ***** *** - ***

1121 23 303877 18-Jun-15 96.8 45.0 ***** *** - ***

1099 24 305911 18-Jun-15 94.9 43.1 ***** *** - ***

1159 25 297928 18-Jun-15 100.1 48.3 ***** *** - ***

987 26 332939 19-Jun-15 85.2 33.4 ***** *** - ***

RATIO MEAN INNER = 0.94

MEAN OUTER

REMARKS:

Calibration factor c.p.s./(microGy/h) 19.3 Cal Cert. 1428544GJ

Cosmic component c.p.s. 0.8

Inherent background component c.p.s. 0.2

Annual Range

APPENDIX B

ENVIRONMENTAL GAMMA DOSERATESSecond Quarter 2015

DOSERATE nGy/h NET DOSERATE nGy/h

Grid Ref Be-7 Uncertainty Cs-137 Uncertainty Co-60 UncertaintyH1TS 342932 5.66 16.2% <0.16 - <0.13 -H2TS 324929 13.76 7.5% <0.15 - <0.16 -H3TS 355942 10.71 9.4% <0.15 - <0.15 -H4TS 365933 8.74 11.9% <0.15 - <0.14 -H5TS 307881 12.63 8.3% <0.15 - <0.12 -H6TS 355852 4.95 18.9% <0.15 - <0.14 -H7TS 423870 7.04 11.9% <0.14 - <0.17 -H8TS 446922 14.75 8.0% <0.16 - <0.16 -

Grid Ref Be-7 Uncertainty Cs-137 Uncertainty Co-60 UncertaintyH1TS 342932 14.67 6.6% <0.15 - <0.15 -H2TS 324929 19.59 6.1% <0.17 - <0.17 -H3TS 355942 27.76 5.4% <0.14 - <0.13 -H4TS 365933 15.85 8.1% <0.16 - <0.14 -H5TS 307881 17.19 6.6% <0.15 - <0.16 -H6TS 355852 4.44 21.5% <0.15 - <0.18 -H7TS 423870 10.53 9.0% <0.15 - <0.14 -H8TS 446922 18.04 6.8% <0.15 - <0.15 -

Grid Ref Be-7 Uncertainty Cs-137 Uncertainty Co-60 UncertaintyH1TS 342932 11.36 8.3% <0.16 - <0.12 -H2TS 324929 18.45 6.5% <0.15 - <0.13 -H3TS 355942 18.55 7.3% <0.14 - <0.17 -H4TS 365933 20.34 5.9% <0.15 - <0.14 -H5TS 307881 15.57 6.8% <0.15 - <0.14 -H6TS 355852 5.70 16.7% <0.14 - <0.16 -H7TS 423870 11.58 10.1% <0.14 - <0.18 -H8TS 446922 18.51 5.7% <0.15 - <0.16 -

Notes:The stated uncertainty is the 2 sigma counting uncertaintyAnnual means and ranges will be reported with the results for the 4th Quarter

Please see overleaf

Site

TEZ GAMMA ACTIVITY (Bq/shade) May

Site

TEZ GAMMA ACTIVITY (Bq/shade) June

APPENDIX C

PASSIVE SHADE GAMMA ACTIVITY ANALYSISSecond Quarter 2015

Site

TEZ GAMMA ACTIVITY (Bq/shade) April

Time of count detection limits for each group of radionuclides measured are detailed in the table below.No specified radionuclides above limits of detection unless stated otherwise.

Co-60, I-131, Cs-134, Cs- 137 Nb-95, Zr-95, Ru-106, Sb-125Ce-144, Eu-154, Eu-155, Ag-110

Time of count

0.18 0.71Detection Limit

(Bq shade -1)

MILK ACTIVITY ANALYSIS

FARMNUMBER K-40 Uncertainty Cs-137 Uncertainty Co-60 Uncertainty

1 44.78 8.83% <0.20 - <0.20 -3 40.52 8.32% <0.21 - <0.17 -4 45.26 8.58% <0.22 - <0.22 -5 41.34 8.45% <0.20 - <0.28 -6 46.10 8.73% <0.20 - <0.19 -7 40.94 8.37% <0.22 - <0.22 -8 49.03 8.25% <0.22 - <0.21 -

NOTES:All milk farms located within 10km of siteThe stated uncertainty is the 2 sigma counting uncertainty

Time of count detection limits for each group of radionuclides measured are detailed in the table below.No specified radionuclides above limits of detection unless stated otherwise.

Time of count Detection Limit

(Bq l -1)

SULPHUR-35 ACTIVITYANALYSIS

S-35 Activity

CARBON-14 ACTIVITY ANALYSIS

190 ± 40 13700 ± 2900235 ± 44 16900 ± 3200

* Derived from the Bq kg -1 (C) measurement on the basis of a 7% carbon content of milk

REMARKSNone

Inner FarmsOuter Farms

Outer Farms <460

Sampling C-14 Activity C-14 Activity

Location Bq kg -1 (C)* (Bqm-3)

0.28 1.07

Sampling

Location (Bqm-3)Inner Farms <570

APPENDIX D

Second Quarter 2015

GAMMA ACTIVITY (Bq l -1)

Co-60, I-131, Cs-137, Cs-134Nb-95, Zr-95, Ru-106, Sb-125

Ce-144, Eu-154, Eu-155, Ag-110

GAMMA SPECTROMETRY ANALYSIS

Gamma Activity (Bq kg-1 wet)

K-40 Uncertainty Cs-137 Uncertainty Co-60 Uncertainty164.96 4.4% <0.40 - <0.47 -169.95 3.9% <0.31 - <0.31 -

Time of count detection limits for each group of radionuclides measured are detailed in the table below. No specified radionuclides above limits of detection unless stated otherwise

SULPHUR-35 ANALYSIS

4.8 ± 1.1 1.54 ± 0.341 ± 0.37 0.148 ± 0.054

CARBON-14 ANALYSIS

* Derived from the Bq kg -1 (C) measurement on the basis of a 3% carbon content of wet herbage

REMARKS1) Annual means and Ranges will be included with the results for the 4th Quarter11) Grid references for the Nearest site and Inner farms are as followed: 355944, 320917, 391936, 358919, 333904111) Herbage from the last four farms (Inner farms) in the above list were bulked prior to analysis

Inner Farms

APPENDIX E

HERBAGE ACTIVITY ANALYSISSecond Quarter 2015

Sampling Location

Nearest Site

Time of count0.47 1.24Detection Limit

(Bq kg -1 wet)

Co-60, I-131, Cs-134, Cs- 137Nb-95, Zr-95, Ru-106, Sb-125

Ce-144, Eu-154, Eu-155, Ag-110

Sampling Location Activity Bq kg -1 (wet) Activity Bq m-2

Nearest SiteInner Farms

Inner Farms 750 ± 100 22.6 ± 3.0 3.33 ± 0.44

Sampling Location Activity Bq kg -1 (C) Activity Bq kg -1 (wet*) Activity Bq m -2

Nearest Site 1110 ± 130 33.4 ± 3.9 10.8 ± 1.3

600 sec SITE NAME CODE DATECOUNT GROSS NET Annual Mean

1050 Trwyn Cemlyn B1 13-May-15 90.7 38.9 ***** *** - ***

1086 Cemlyn B2 13-May-15 93.8 42.0 ***** *** - ***

1135 Cemlyn Beach B3 29-Apr-15 98.0 46.2 ***** *** - ***

1093 Cerrig Brith B4 13-May-15 94.4 42.6 ***** *** - ***

1154 Porth y Pistyll B5 18-Jun-15 99.7 47.8 ***** *** - ***

975 Porth y Ogof B6 03-Jun-15 84.2 32.4 ***** *** - ***

1016 Porth Wylfa B7 03-Jun-15 87.7 35.9 ***** *** - ***

1214 Cemaes Bay B8 19-Jun-15 104.8 53.0 ***** *** - ***

1163 Porth Padrig B9 19-Jun-15 100.4 48.6 ***** *** - ***

1174 Porth Wen B10 19-Jun-15 101.4 49.6 ***** *** - ***

1188 Porth Llechog B11 19-Jun-15 102.6 50.8 ***** *** - ***

1196 Porth Amlwch B12 18-Jun-15 103.3 51.5 ***** *** - ***

1231 Creek Amlwch B13 18-Jun-15 106.3 54.5 ***** *** - ***

1175 Porth Wnal B14 13-May-15 101.5 49.7 ***** *** - ***

REMARKSGross Doserates - Uncorrected DoseratesNet Doserates - Measured readings minus the cosmic component and inherent background.

The doserates at the beaches continue to be at an elevated level due to the instrument used giving readings approximately 25% higher than an alternative instrument used for comparison. This was not discovered until after the Q2 2015 surveys were completed. None of the results exceeded any statistical tests this quarter. An alternative instrument will be used for the surveys in Q3.

Calibration factor c.p.s./(microGy/h) 19.3 Cal Cert. 1428544GJCosmic component c.p.s. 0.8Inherent background component c.p.s. 0.2

Annual Range

APPENDIX F

BEACH GAMMA DOSERATE MONITORINGSecond Quarter 2015

DOSERATE nGy/h NET DOSERATE nGy/h

Sediment

Dry/

Sample Location Code Date Wet

Ratio Activity Uncertainty Activity Uncertainty Activity Uncertainty Activity Uncertainty Activity Uncertainty

Silt Cemaes Bay HO/SL/B8 12-May-15 0.68 398.64 3.6% 14.47 3.9% <0.72 - 7.04 21.7% 473 8.5%

Cemlyn HO/SL/BC 12-May-15 0.63 485.54 3.4% 45.49 2.8% <0.99 - 14.55 17.6% 648 6.8%

Flora and Fauna

Dry/

Sample Location Code Date Wet

Ratio Activity Uncertainty Activity Uncertainty Activity Uncertainty Activity Uncertainty Activity Uncertainty

Seaweed Wylfa Outfall HO/SW/BW 13-May-15 0.29 379.28 3.4% 1.31 22.9% <0.62 - <0.55 - 304.0 5.3%

Cemlyn HO/SW/BC 12-May-15 0.22 290.85 3.8% 0.72 32.1% <0.52 - <0.38 - 259.0 5.0%

Cemaes Bay HO/SW/B8V 12-May-15 0.22 303.63 3.4% 0.73 31.5% <0.39 - <0.39 - 261.0 5.0%

Cemaes Bay HO/SW/B8P 12-May-15 0.20 223.49 3.6% 0.72 26.0% <0.43 - <0.27 - 144.0 6.3%

Crustacea Crab HO/CR/00 30-Jun-15 0.25 93.22 9.2% <0.48 - <0.44 - <0.50 - 93.3 9.4%

Lobster HO/LO/00 30-Jun-15 0.30 180.37 7.0% <0.69 - <0.58 - <0.60 - 116.0 9.5%

Molluscs Winkle HO/WI/00 09-Jun-15 0.27 85.60 9.2% 0.78 33.5% <0.52 - <0.38 - 78.0 11.2%

Fish Bass HO/BA/00 30-Jun-15 0.23 138.88 9.0% 0.89 37.3% <0.49 - <0.56 - 125.6 7.4%

Time of count detection limits for each group of radionuclides measured are detailed in the table below.No Specified radionuclide above limits of detection unless stated otherwise

Notes

(i) The stated uncertainty is the 2 sigma counting uncertainty.

(ii) V = Fucus vesiculosus P = porphyra.

The Cs-137 and K-40 activty in the Lobster sample exceeded the mean plus 3 standard deviations and the mean plus 4 standard deviations of the previous 12 results. These were not

reported to the Environment Agency as the Cs-137 result was below the minimum detectable activity (MDA) and was below the minimum detection limit specified in the CEARAS, and

the K-40 is a naturally occurring nuclide and therefore not reported as previously agreed.

(Bq kg -1 ) wet 0.69 2.99

Time of countCo-60, I-131, Cs-134, Cs- 137

Nb-95, Zr-95, Ru-106, Sb-125

Detection Limit Ce-144, Eu-154, Eu-155, Ag-110

(Bq kg -1 ) dry 0.99 2.66

GAMMA SPECTROMETRIC DATA (Bq kg -1 Wet) GROSS BETA

K-40 Cs-137 Co-60 Mn-54 (Bq kg -1 Wet)

APPENDIX G

MARINE ACTIVITY ANALYSISSecond Quarter 2015

GAMMA SPECTROMETRIC DATA (Bq kg -1 Dry) GROSS BETA

K-40 Cs-137 Co-60 Am-241 (Bq kg -1 Dry)

Date of Survey: 10/06/2015

Instrument used:Electra / EP15 Serial no. 4862Radeye SX / 44-10 Serial no. 905/PR313001

Remarks:None

APPENDIX H

STRANDLINE MONITORINGSecond Quarter 2015

Porth-yr-Ogof 150 Nil above background detected

LOCATIONLENGTH OF STRANDLINE

MONITORED (m) RESULT