ECOLOGICAL RISK ASSESSMENT AND ASSESSMENT OF EFFECTS ON NON- HUMAN BIOTA TECHNICAL SUPPORT DOCUMENT NEW NUCLEAR – DARLINGTON NK054-REP-07730-00022 Rev 000 Submitted To: Ontario Power Generation Inc. Prepared By: SENES Consultants Limited September 2009 New Nuclear – Darlington Ecological Risk Assessment Environmental Assessment and Assessment of Effects on Non-Human Biota Ontario Power Generation Inc. Technical Support Document EXECUTIVE SUMMARY Ontario Power Generation (OPG) was directed by the Ontario Minister of Energy in June 2006 to begin the federal approvals process, including an environmental assessment (EA), for new nuclear units at an existing site. This Ecological Risk Assessment and Assessment of Effects on Non-Human Biota TSD was written in support of the EA for the New Nuclear – Darlington (NND) Project. This TSD describes the potential effects on non-human biota as a result of exposures to radiological and conventional constituents from NND. The assessment of effects of the Project was completed in two stages: 1) Assess the baseline (existing) environmental exposures to non-human biota; and 2) Determine the potential incremental exposures as a result of the NND Project. A baseline data collection program was designed and implemented to assess the existing concentrations of constituents and radionuclides in the Site, Local and Regional Study Areas. The baseline program was developed using the preliminary description of the NND Project and a review of previous Ecological Risk Assessments (ERAs) completed for the DN site. The baseline program collected information on concentrations of radiological and conventional constituents in various environmental media. A screening process was undertaken related to constituents measured in water (i.e. Lake Ontario and on-site ponds), sediments (Lake Ontario and on-site ponds) and soils (site-wide) to identify constituents of potential concern (COPCs) in the existing environment. The screening process identified hydrazine as a conventional COPC in Lake Ontario water and cadmium, copper, lead and selenium in Lake Ontario sediments; boron, cobalt, iron, hydrazine, manganese, strontium in the water and copper in the sediments of Coots Pond; and strontium and zirconium in the soils on the site. Seven radionuclides were selected to be used in the risk assessment due to their prevalence in the environment, historical concerns regarding environmental concentrations and relevance to nuclear power generation. These radionuclides were C-14, H-3, Sr-90, Co-60, Cs-134, Cs-137 and I-131. The methodology used in assessing the effects on non-human biota (i.e. ecological risks) for the existing conditions followed guidelines outlined by various regulatory agencies including Environment Canada and the Canadian Council of Ministers of the Environment (CCME 1996). Four different steps were considered as provided in the various regulatory frameworks. They are: x the problem formulation stage, in which the various chemicals of concern, receptors, exposure pathways, and scenarios are identified; x the exposure assessment, where predicted exposures are calculated for the various receptors and COPC; x the hazard assessment, in which exposure limits for the COPC are determined; and, x the risk characterization stage, where the exposure and hazard assessment steps are integrated. ES-1 New Nuclear – Darlington Ecological Risk Assessment Environmental Assessment and Assessment of Effects on Non-Human Biota Ontario Power Generation Inc. Technical Support Document The exposures to the identified COPCs were determined for a selected group of ecological receptors. These ecological receptors were selected to cover a wide range of exposures and represent the characteristics of other ecological species within the environment. These exposures were then compared to published toxicity reference values for conventional constituents and reference dose rates for radionuclides. A screening index (SI) value approach was used to assess the effects of conventional COPC and radionuclides on ecological receptors in the existing environment. The evaluation determined that for the existing conditions, radionuclide doses were well below any reference dose rates. Also, conventional COPC exposure would not result in any adverse effects to non-human biota in the existing environment. Although the assessment for amphibians under existing conditions resulted in Screening Index values above one for strontium in Coots Pond and Tree Frog Pond, site-specific field evidence collected on amphibians at the site indicate that these ponds provide breeding grounds for six species of amphibians and healthy populations exist thus there are no adverse effects on amphibian populations in any of the on-site ponds in the existing environment. Following the determination of the risks associated with COPCs from the existing conditions to the ecological receptors, the detailed project description was reviewed to determine if there were any potential new or additive COPCs resulting from the Project works and activities. For this assessment, the conclusions identified by the Surface Water, Atmospheric and Geology and Hydrogeology technical specialties were reviewed for applicable information on potential changes in surface water, atmospheric, soil and groundwater quality. No measurable changes in the quality of these environmental components or project-related COPCs were identified for a bounding release scenario. A qualitative assessment was conducted for conventional COPC and a preliminary quantitative assessment was carried out for the radionuclide COPC for the proposed NND based on the information presented from the other work groups. The assessment indicated that no potential adverse effects on non-human biota were expected as a result of radionuclide and conventional constituent emissions from the NND Project. ES-2 New Nuclear – Darlington Ecological Risk Assessment Environmental Assessment and Assessment of Effects on Non-Human Biota Ontario Power Generation Inc. Technical Support Document TABLE OF CONTENTS SPECIAL TERMS.......................................................................................................................viii GLOSSARY OF TERMS...............................................................................................................x LIST OF TECHNICAL SUPPORT DOCUMENTS (TSDs) ...................................................... xvi 1.0 INTRODUCTION ...........................................................................................................1-1 1.1 Background.......................................................................................................... 1-1 1.1.1 The New Nuclear - Darlington Project .................................................... 1-1 1.1.2 The New Nuclear - Darlington Environmental Assessment.................... 1-2 1.2 Technical Support Document .............................................................................. 1-2 1.3 Description of the Ecological Risk Assessment Component............................... 1-3 2.0 EA METHODOLOGY ....................................................................................................2-1 2.1 Existing Environment Characterization Program ................................................ 2-1 2.1.1 Characterization Program Framework..................................................... 2-1 2.1.1.1Define the Baseline Data Requirements ...................................... 2-2 2.1.1.2Conduct Gap Analysis ................................................................. 2-2 2.1.1.3Develop Baseline Data Collection Program ................................ 2-2 2.1.1.4Implement Baseline Data Collection Program ............................ 2-2 2.1.2 Characterization Program Design............................................................ 2-2 2.1.3 Project – Environment Interactions with the Assessment of Ecological Risk ........................................................................................ 2-4 2.1.4 Data Quality Objectives Related to the ERA........................................... 2-4 2.1.5 Existing Information and Gap Analysis in the Ecological Risk Assessment............................................................................................... 2-4 2.1.5.1Review of Previous ERAs Conducted at the DN Site ................. 2-5 2.1.5.2Exposure Data Gaps..................................................................... 2-6 2.1.5.3Gaps in Pathway Development Information................................ 2-6 2.1.6 Baseline Characterization Data Requirements in the Ecological Risk Assessment ...................................................................................... 2-6 2.1.7 Review and Reiteration............................................................................ 2-6 2.1.8 Summary of Environmental Baseline Characterization Program............ 2-7 2.1.9 Interactions with Other Environmental Components .............................. 2-7 2.2 Existing Environment and Effects Assessment ................................................... 2-7 2.2.1 Analytical Methods for the Assessment .................................................. 2-7 2.2.2 Criteria for the Assessment...................................................................... 2-7 2.2.3 Characterizing the Existing Environment................................................ 2-8 2.2.4 Process Steps for Determination of Likely Environmental Effects of the Project...........................................................................................