2014 Results of OPG s Pickering and Darlington Environmental Monitoring Programs

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1 2014 Results of OPG s Pickering and Darlington Environmental Monitoring Programs Presentation to Joint PN and DN CAC June 16th, 2015 Presented By: Carina Cautillo

2 Station Emissions Monitoring Objectives : Demonstrate adequacy of emission controls and compliance with DRLs and action levels Provide data to assess and confirm environmental impact predictions Provide assurance to stakeholders and the public Monitoring results for both radiological and non-radiological emissions are reported to: The regulator (CNSC) every quarter via the Quarterly Operations Reports The public via the Environmental Emissions Data Reports on 2

3 Monitoring Radioactivity in the Environment Objectives : Demonstrate station radioactive emissions are properly controlled. Obtain environmental data to estimate public doses Use data to evaluate of transport models used to calculate station DRLs and public doses Sample environmental media at site boundary and critical group locations: Air Drinking Water Milk Lake Water Fruits/Vegetables Fish Beach Sand Animal Feed Soil (every 5 years) Eggs/ Poultry Sediment (every 5 yrs) Sample at background locations in Ontario to determine net impact of DN and PN operations Monitoring results and estimated public doses reported to the regulator (CNSC) on an annual basis 3

4 2014 Results - Summary Station radiological emissions were all below 1.5% of their respective DRLs in 2014 Annual public doses resulting from PN and DN operations in 2014 were 1.2 μsv and 0.6 μsv respectively; approximately 0.1% of the annual regulatory limit Dose calculations and annual report were reviewed and verified by an independent third party EMP report is available at 4

5 DN Critical Groups and Sampling Locations 1. Non-Dairy Farmers 2. Dairy Farmers 3. Rural Residents

6 Darlington Station 2014 Public Dose Darlington public dose continues to be very low and is consistent with the 2013 dose 2014 public dose was 0.6 μsv - represented by the Farm Adult- HTO and C-14 are the major dose contributors 0.1% of the annual regulatory limit of 1000 μsv and <0.1% of annual natural background radiation of 1,400 μsv 6

7 PN Critical Groups and Sampling Locations 1. Correctional institute 2. Urban residents 3. Industrial/Commercial workers 4. Dairy farmers

8 Pickering Station 2014 Public Dose Pickering public dose continues to be very low and is consistent with the 2013 dose 2014 public dose was 1.2 μsv - represented by an Urban Residential Adult Noble gas and Tritium are major dose contributors 0.1% of the annual regulatory limit of 1000 μsv and of annual natural background radiation of 1,400 μsv 8

9 2014 Results of Radioactive Emissions Monitoring All radioactive emissions to air and to water were below 1.5% of station DRLs 9

10 Results of Non-Rad Emissions Monitoring The station Quarterly Operations Reports (QORs) provide non-radiological emissions for the previous calendar year Below are the 2013 emissions, taken from the 2014 QORs 10

11 2014 Environmental Monitoring Results 958 laboratory analyses performed for the 2014 dose calculation 11 Tritium in vegetation increased in 2014 as compared with 2013 for both DN and PN critical group locations, consistent with the increase in tritium to air emissions observed in C-14 in vegetation remains similar to previous years. Tritium in C-14 in milk remain similar to concentrations observed in C-14 concentrations are stable and near background levels. Tritium, C-14, and noble gases in air measured at boundary locations around DN and PN remained similar to concentrations observed in previous years and are reflective of the station emissions trends. Tritium in drinking water measured at local water supply plants remained at a small fraction of the Ontario Drinking Water Quality Standard of 7000 Bq/L.

12 2014 Supplementary Studies Supplementary studies are site-specific and as such may vary between nuclear facilities. These studies become part of the EMP until the objective of the study has been achieved. At that time, the supplementary study is terminated. In 2014 OPG conducted two supplementary studies in support of the PN and DN EMPs: (a) Hydrazine in Lake Water near PN. (b) Chlorine and Morpholine in Lake Water near DN Hydrazine and Morpholine: Used in OPG station water systems to prevent corrosion. These chemicals are released when steam is vented to the atmosphere and when water from the boilers is drained to Lake Ontario Chlorine: Sodium hypochlorite used as a biocide to control mussel infestations in station water systems that use lake water. 12

13 PN Hydrazine in Lake Water Scope: Determine if the hydrazine concentrations in Lake Ontario near the PN outfalls and in Frenchman s Bay pose risks to: (a) Humans (through drinking water and fish consumption) (b) Invertebrates and aquatic plants through exposure to lake water Samples were submitted to a laboratory that was capable of obtaining a detection limit of 1 μg/l Three sampling events (22 July, 15 August and 10 September 2014); Three locations at the PN-A and PN-B outfalls (~100 m, 250 m and 500 m from discharge) Two downstream locations (500 m and 1000 m downstream of PN according to the plume direction at time of sampling); Samples collected at top, middle and bottom of the water column at all locations 13

14 PN Hydrazine in Lake Water contd. Results: The concentrations of hydrazine were below all benchmarks for the various receptors identified in the PN ERA, hence no human health or ecological effects are expected. 14

15 DN Chlorine and Morpholine in Lake Water Scope: Conduct lake water sampling for Total Residual Chlorine (TRC) and morpholine near the DN discharge to determine if: (a) TRC concentrations remain below the Provincial Water Quality Objective (PWQO) of 2 μg/l, and less than the toxicity reference values for aquatic life. (b) Morpholine concentrations are less than the PWQO of 4 μg/l and the toxicity reference values for aquatic life. Three sampling events (26 June, 14 August and 9 September 2014); Three locations along the diffuser near shore, mid-point, and far end) Two downstream locations (500 m and 1000 m downstream of the diffuser according to the plume direction at time of sampling); Samples collected at top, middle and bottom of the water column at all locations. 15

16 DN Chlorine and Morpholine in Lake Water contd. Results: All samples of morpholine and TRC collected in all three sampling events were less than their method detection limits of 1 ug/l and 1.2 ug/l, respectively. Consequently the exposure point concentration for morpholine is < 1 μg/l, and < 1.2 ug/l for TRC, both of which are less than the lowest benchmark values. There is no risk of ecological effects from these substances in Lake Ontario near the Darlington Nuclear facility. 16

17 Looking Forward Supplementary studies conducted as part of the 2015 EMPs include: Particulate and I-131 in air around PN and DN boundaries to support the EMP objective of confirming the effectiveness of effluent control and effluent monitoring. Results will be discussed in the 2015 EMP report 17

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19 Questions? 19

20 Additional Slides 20

21 Definition of Terms Becquerel (Bq) - Unit of activity, the rate at which transformations occur in a radioactive substance. 1 Bq = 1 transformation or disintegration per second Sievert (Sv) - SI unit of the amount of ionizing radiation dose required to produce the same biological effect as one unit of high penetration X-rays Derived Release Limit (DRL) amount of radionuclide released in one year that would result in a member of the most exposed group around PN and DN receiving a dose equal to the regulatory limit of 1000 μsv/yr Critical Groups members of the public living near the nuclear stations who form a homogenous group with respect to their proximity to the station, diet, habits, and age 21

22 Transition from REMP to EMP CSA N Environmental Monitoring Programs for Class I Nuclear Facilities and Uranium Mines and Mills, was published in May 2010 to supersede the previous 1990 version of this standard CSA N version 2010 version Receptors Human Human Environment (non-human biota) Stressors Nuclear substances Nuclear substances Hazardous substances Physical stressors 22

23 Transition from REMP to EMP (continued) The CSA N compliant EMP was designed using a risk-based approach relying heavily on the results of the PN and DN Environmental Risk Assessments (ERAs) Key features of the new EMP design include: Both radiological and non-radiological station emissions provided in annual report Scheduled supplementary studies for monitoring of non-radiological contaminants of concern Dose calculation performed for fewer critical group locations but with a higher number of samples collected per critical group Replicate sampling incorporated for terrestrial and aquatic sampling Sampling locations and media modified to better represent public dose critical groups Statistical analyses performed on datasets (mean, standard deviation, trend analysis, demonstration that the concentrations of contaminants are below the benchmark value etc.) Discussion of other OPG monitoring programs provided in annual EMP report 23

24 Other Monitoring Programs The overall EMP encompasses several other OPG monitoring programs to meet objectives beyond supporting the annual public dose calculation. Thermal Monitoring Program Discharge of warm water through the condenser cooling water (CCW) system has the potential to impact spawning success and larvae development of round whitefish At PN, a three year thermal monitoring program was completed in 2013 and concluded that the thermal plume presents minimal risk to round whitefish spawning in the area At DN, a study to support the DNGS Refurbishment and Continued Operation Environmental Assessment confirmed that the current performance of the diffuser is effective in protecting round whitefish populations A re-assessment of the impacts of the thermal emissions from DN and PN on the survival of round whitefish eggs in Lake Ontario was performed in The re-assessments concluded that the risk of thermal emissions on round whitefish is low and no further mitigation or offsetting is warranted 24

25 Other Monitoring Programs contd. Impingement and Entrainment Monitoring Program In October 2008 the CNSC issued a directive to OPG to reduce impingement of all species of fish at Pickering Nuclear by 80% PN installed a barrier net covering the entire intake channel in 2009 to meet the reduction target A project was initiated in 2014 to improve approximately 3 ha of wetland habitat at Duffins Creek to offset residual impingement Entrainment cannot be practically reduced, but equivalent ecological benefit was realized by undertaking a fish stocking program Due to a different intake design, DN does not experience the same fish impingement and entrainment issues as PN Groundwater Monitoring Program Annual program to evaluate groundwater quality across the sites and to detect any emergent issues The 2013 annual results did not differ appreciably from previous years 25

26 Tritium Tritium = H-3 (2 neutrons, 1 proton) Naturally occurring and by-product of weapons testing Majority of tritium is produced in the moderator and heat transport system D 2 0 (D = 1 neutron, 1 proton) Primary pathway for public dose at PN: inhalation due to airborne emissions 26

27 Noble Gases Predominantly Ar-41, with much smaller amounts of Xe-133 and Xe-135 Radioactive noble gases are produced when air is present within containment and molecules become activated (i.e. Ar-40 -> Ar-41). Air ingress occurs via leakage points such as equipment that penetrates the containment wall. Primary pathway for public dose at PN: external exposure due to airborne emission 27

28 Carbon-14 Naturally occurring and by-product of nuclear weapons testing Majority of C-14 is produced in the moderator system by neutron activation of O-17 Primary pathway for public dose at PN: ingestion of locally grown produce (due to airborne emission) 28