6.0 ENVIRONMENTAL AND SOCIO-ECONOMIC EFFECTS ASSESSMENT

Transcription

1 6.0 ENVIRONMENTAL AND SOCIO-ECONOMIC EFFECTS ASSESSMENT The description of the environmental and socio-economic setting, and current state of the environment within the Project area (Section 5.0), are compared in this section of this ESA against the Project Description (Section 2.0) to identify potential effects that might be caused by the Project. The environmental and socio-economic effects assessment uses the information provided in the environmental and socio-economic setting to: evaluate the environmental and socio-economic elements of importance in the Project area; identify the changes to the Project caused by the environment; develop appropriate site-specific mitigation measures and, when appropriate, enhancement measures that are technically and economically feasible; and identify and evaluate potential Project effects associated with each environmental and socio-economic element of importance. In addition, the environmental and socio-economic effects assessment has determined the significance of potential residual effects resulting from construction and operation activities after taking into consideration proposed mitigation. 6.1 Methodology The assessment evaluated the environmental and socio-economic effects of the construction, operation, and final decommissioning or abandonment phases of the pipeline and facilities components of the Project. The assessment also evaluated the effects of the decommissioning of the existing Line 3. The assessment method included the following components: determination of spatial and temporal boundaries for the assessment; identification of environmental and socio-economic elements; identification of potential environmental and socio-economic effects; development of technically and economically feasible mitigation and, where appropriate, enhancement measures; identification of anticipated residual effects; and determination of the significance of residual effects. This environmental and socio-economic effects assessment methodology has been developed based on the following. The Responsible Authority's Guide to the Canadian Environmental Assessment Act: Part II The Practitioner s Guide (Federal Environmental Assessment Review Office [FEARO] 1994a). FEARO s A Reference Guide for the Canadian Environmental Assessment Act: Addressing Cumulative Environmental Effects (FEARO 1994b). FEARO s A Reference Guide for the Canadian Environmental Assessment Act: Determining Whether a Project is Likely to Cause Significant Environmental Effects (FEARO 1994c). The CEA Agency Cumulative Effects Assessment Practitioners Guide (Hegmann et al. 1999). CEA Agency s Incorporating Climate Change Considerations in Environmental Assessment (CEA Agency 2003). Page 6-1

2 CEA Agency s Addressing Cumulative Environmental Effects under the Canadian Environmental Assessment Act, 2012 (CEA Agency 2013). The NEB OPR. The CEA Act, The NEB Filing Manual (NEB 2014a). The environmental and socio-economic effects assessment associated with the construction and operation of the Project was a collaborative effort of several qualified professionals with element-specific expertise, under the guidance of representatives of TERA. Table acknowledges the contribution of these experts and professionals by environmental and socio-economic element. TABLE ENVIRONMENTAL AND SOCIO-ECONOMIC EFFECTS ASSESSMENT TEAM Environmental/Socio-Economic Element Physical and Meteorological Environment Soil and Soil Productivity Water Quality and Quantity Air Emissions GHG Emissions Acoustic Environment Fish and Fish Habitat Wetlands Vegetation Wildlife and Wildlife Habitat Species At Risk Human Occupancy and Resource Use Heritage Resources TLRU Social and Cultural Well-Being Human Health Infrastructure and Services Navigation and Navigation Safety Employment and Economy Accidents and Malfunctions Effects of the Environment on the Project Assessor TERA Mentiga and TERA TERA Stantec and TERA RWDI and TERA ACI and TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA TERA Spatial and Temporal Boundaries The spatial boundaries (e.g., Footprint, LSA, RSA) used to evaluate the potential effects of the Project on the environment are presented in Table and in Section 6.2 for each applicable element. Spatial ecological boundaries were determined by the distribution, movement patterns and potential zones of interaction between an element and the Project. The ecological boundary may be limited to the Footprint (e.g., construction right-of-way, temporary workspace and temporary facilities) or may extend beyond the physical boundaries of the area of the Project component since the distribution or movement of an element can be local, regional or provincial, national or international in extent. The time frames used in the assessment of the Project includes the planning, construction, operation and final decommissioning or abandonment phases (Table ). The construction phase includes surveying, clearing, topsoil salvage, grading, trenching, testing and reclamation for the replacement pipeline, decommissioning and permanent facilities. Pipeline construction activities are assumed to begin in Q with an in-service date of Q Construction of the temporary construction camp is expected to commence in Q preceding pipeline Page 6-2

3 construction. Construction activities related to the permanent facilities will also commence upon receipt of an Order pursuant to Section 58 of the NEB Act. It is expected that the proposed facilities at Hardisty and Cromer terminals, and Metiskow, Kerrobert, Milden, Craik, Rowatt, Glenavon, Glenboro and Gretna stations will be in service by Q and the proposed facilities at Cactus Lake, Herschel, Loreburn, Bethune, Odessa, Langbank, West Souris and St. Leon stations will be in service by Q A detailed construction schedule for the Project is provided in Section 2.0. The operation phase commences following completion of pipeline construction in Q and extends for the useful life of the pipeline (approximately 50 years) Environmental and Socio-Economic Elements The potential environmental (i.e., biophysical) and socio-economic elements interacting with the Project were identified through the regulatory and government consultation process, experience gained during previous pipeline projects with similar conditions/potential issues (e.g., CEP, SEP II, TP I, TP II, ACEP, SLP, L4EP, EHP, SLFO, ACCE I, and ACCE II), as well as the professional judgement of the assessment team. Issues noted during public consultation with federal, provincial and municipal government agencies, local industry representatives, interested stakeholders and the general public were essential in determining element interactions with the Project (Section 3.0). Environmental and socio-economic elements potentially interacting with the Project include: physical elements, such as physical and meteorological environment, soil and soil productivity, water quality and quantity, air emissions, GHG emissions and acoustic environment; biological elements, such as fish and fish habitat, wetlands, vegetation, wildlife and wildlife habitat, and species at risk; and socio-economic elements, such as human occupancy and resource use, heritage resources, TLRU, social and cultural well-being, human health, infrastructure and services, navigation and navigation safety, and employment and economy. Effects arising from potential accidents and malfunctions, and changes to the Project caused by the environment were also considered. Those environmental and socio-economic elements which are not considered to interact with the Project are identified and justified in Sections 6.2, 6.3 and 6.5. In accordance with Guide A.2.6 of the NEB Filing Manual, no further analysis is necessary for those elements where interactions between the Project component and an environmental or socio-economic element are not predicted Potential Environmental and Socio-Economic Effects Guide A of the NEB Filing Manual assumes that identification of potential environmental and socio-economic effects reflects a valued component based approach where the valued components could be the broad elements as described in Tables A-1 Circumstances and Interactions Requiring Detailed Biophysical and Socio-Economic Information, A-2 Filing Requirements for Biophysical Elements and A-3 Filing Requirements for Socio-Economic Elements or a representative subset of those elements. Given the scope of the Project, the identification of the potential environmental and socio-economic effects focuses on the broad environmental (i.e., biophysical) and socio-economic elements as the valued components. Many of the potential effects associated with the physical process of decommissioning a pipeline are similar to the potential issues associated with pipeline construction, specifically, those related to activities that entail surface disturbance (i.e., clearing, topsoil salvage, excavation, backfilling, topsoil replacement, revegetation, temporary access, spill prevention and clean-up). These issues are well understood and have proven mitigation measures. The potential issues that are specific to decommissioning a pipeline in-place are: ground subsidence; Page 6-3

4 soil and groundwater contamination; erosion and slope stability; and the potential for water conduits. The potential environmental and socio-economic effects resulting from the Project were identified through: consultation with Aboriginal groups, landowners, communities and municipalities near facilities and along the replacement pipeline right-of-way, the general public, government and regulatory agencies; experience gained during previous pipeline projects, including those with similar conditions/potential issues; and the professional judgement of the assessment team. The potential environmental and socioeconomic effects arising from the construction and operation of the pipeline and associated facilities are identified in Sections 6.2 and 6.3. Section 6.4 outlines the potential effects associated with temporary facilities. The potential environmental and socio-economic effects arising from decommissioning are identified in Sections 6.5 and Mitigation and Enhancement Measures Mitigation, as defined under the CEA Act, 2012, is considered to be the elimination, reduction or control of a project s adverse environmental effects, including restitution for any damage to the environment caused by such effects through replacement, restoration, compensation or any other means. This definition also applies to reducing or managing a project's adverse socio-economic effects. For the purposes of this assessment, TERA defines an enhancement measure as a recommendation that aims to promote the likelihood of potential positive environmental or socio-economic residual effects. To ensure that the severity of potential adverse environmental and socio-economic effects are reduced and that potential positive socio-economic effects are enhanced during pipeline construction and operation, general and site-specific mitigation measures (including enhancement measures) have been recommended based upon current industry-accepted standards, consultation/engagement with regulatory agencies and the professional judgement of the assessment team. Mitigation measures suggested by government agencies or other stakeholders have been incorporated into this assessment including AEP (1994, 1998), AENV (1988, 1994, 1995), Alberta Pipeline Environmental Steering Committee (1996) and CAPP (1996, 1999, 2008). Mitigation measures (including enhancement measures) are identified in Sections 6.2 to 6.6 as well as in the Project-specific EPPs (Appendices 1A and 1B). Mitigation measures recommended in element-specific technical reports have also been integrated into the assessment. Various guidelines and requirements of federal and provincial regulatory agencies, and industry standards and guidelines have been taken into consideration in this ESA and, where applicable, are referenced for each element. Accompanying this ESA is the Environmental Alignment Sheet Package (Appendix 2) which identifies where some site-specific mitigation measures are to be implemented. Environmental Inspector(s) will be retained by Enbridge to help ensure that the mitigation measures within this ESA are understood and properly implemented during construction. Environmental inspection is further described in Section 8.0. In addition, it is expected that through the ongoing consultation program, additional issues related to the Project may be identified, and further mitigation and enhancement measures may be developed Residual Effects Residual effects are the environmental and socio-economic effects remaining following the implementation of mitigation (including enhancement measures). In many situations, the recommended mitigation measures will completely mitigate the potential adverse effects while in other situations, the mitigation measures will lessen the effects, but do not entirely eliminate the effects. Elements for which no effects are predicted require no further analysis Significance Evaluation of Potential Residual Effects The determination of significance of potential residual effects generally followed the guidelines and principles of the NEB Filing Manual, FEARO s The Responsible Authority's Guide to the Canadian Environmental Assessment Act: Part II: The Practitioner s Guide (FEARO 1994a), FEARO s A Reference Page 6-4

5 Guide for the Canadian Environmental Assessment Act: Addressing Cumulative Environmental Effects (FEARO 1994b), FEARO s A Reference Guide for the Canadian Environmental Assessment Act: Determining Whether a Project is Likely to Cause Significant Environmental Effects (FEARO 1994c), and the CEA Agency s Cumulative Effects Assessment Practitioners Guide (Hegmann et al. 1999). The agencies identify several possible methods for the determination of whether residual environmental or socio-economic effects are significant. These include: the use of regulatory environmental standards, guidelines or objectives in relation to potential residual effects; quantitative assessment of residual effects; and qualitative assessment of the residual effects. The NEB Filing Manual indicates that the quantitative method should be used where possible; otherwise, the qualitative method can be used. Some elements can be assessed quantitatively using regulatory standards and guidelines. Where there are no standards, guidelines, objectives or other established and accepted thresholds to define quantitative rating criteria or where quantitative thresholds are not appropriate, the qualitative method that is based on available literature is considered to be the appropriate method for determining the significance of the potential residual effects. Consequently, the significance for most of the potential residual effects is evaluated by developing a set of qualitative criteria based on those identified by Hegmann et al. (1999). These criteria are identified below and their definitions are presented in Table Spatial boundary (i.e., Footprint, LSA, RSA, Provincial, National and International). Temporal context (i.e., duration and frequency of the event causing the residual effect, and reversibility of the residual effect). Magnitude (i.e., severity of the residual effect in relation to environmental, social and/or regulatory standards). Level of confidence or uncertainty (i.e., availability of data to substantiate the assessment conclusion, previous success of mitigation measures, etc.). Probability or likelihood of occurrence of the residual effect. TABLE CHARACTERIZATION OF RESIDUAL EFFECTS FOR EVALUATION OF SIGNIFICANCE 1 Assessment Criteria Definition IMPACT BALANCE - of the Residual Effect Positive Residual effect has a net benefit to the environment or socio-economic conditions. Neutral Residual effect has no net benefit or loss to the environment or socio-economic conditions. Negative Residual effect has a net loss or is a detriment to the environment or socio-economic conditions. SPATIAL BOUNDARY - Location of Residual Effect Footprint The land area directly disturbed by the Project construction activities, including associated physical works and activities (e.g., construction right-of-way, remote sectionalizing valves, permanent facilities, temporary workspace and temporary facilities). LSA An LSA that varies with the environment and resource use related socio-economic element being considered. For each element considered, the LSA is established based on the ZOI within which plants, animals and humans are most likely to be affected by Project construction and operation. Detailed discussions regarding the LSAs and associated rationale are provided in Section 6.2. For social elements (e.g., HORU), local potential effects are related to specific communities considered in the socio-economic assessment. The communities considered were based on whether there would be direct potential effects, such as a physical, social or economic interaction between the Project and the community or community residents and their economic, social or cultural resources and pursuits. RSA An RSA consists of the area extending beyond the LSA boundary and varies with the environment and resource use-related socio-economic element being considered. For each element considered, a separate RSA boundary was established in consideration of the Project regional effects on the individual element. Further rationale for the establishment of the RSAs for the Project is provided in Section 6.2. Page 6-5

6 Assessment Criteria Provincial National International TEMPORAL CONTEXT Duration - Immediate (Period of the Short-term Event Causing Long-term the Effect) Frequency 2 - (How Often Would the Event that Caused the Effect Occur) Reversibility - Environmental (Period of Time Over Which the Residual Effect Extends) Reversibility Socio-economic (Period of Time Over Which the Residual Effect Extends) Accidental Isolated Occasional Periodic Continuous Immediate Short-term Medium-term Long-term Permanent Short-term Medium-term Long-term Permanent TABLE Cont'd Definition The area extending beyond regional or administrative boundaries, but within Alberta, Saskatchewan or Manitoba. The area extending beyond Alberta, Saskatchewan or Manitoba, but confined to Canada. The area extending beyond Canada. Event is limited to less than or equal to 2 days during either the construction phase or operations phase. Event occurs during the construction phase or is completed within any 1 year during the operations phase. Ongoing event that is initiated during the construction phase and extends beyond the first year of the operations phase or is initiated during the operations phase and extends for the life of the Project. Event occurs rarely over assessment period. Event is confined to a specified phase of the assessment period. Event occurs intermittently and sporadically over the assessment period. Event occurs intermittently, but repeatedly over the assessment period. Event occurs continually over the assessment period. Residual effect is alleviated in less than or equal to 2 days. Greater than 2 days and less than or equal to 1 year to reverse residual effect. Greater than 1 year and less than or equal to 10 years to reverse residual effect. Greater than 10 years to reverse residual effects. Residual effects are irreversible. Residual effect limited to the construction phase or to less than any 1 year during the operations phase. Residual effect extends into the first 2 years of the operations phase. Residual effect extends beyond the first 2 years of the operations phase. Residual effects are irreversible. MAGNITUDE 3 - of the Residual Environmental Effect Negligible Residual effects are not detectable from existing (baseline) conditions. Low Residual effects are detectable, but well within environmental and/or regulatory standards. Medium Residual effects are detectable and may approach, but are still within the environmental and/or regulatory standards. High Residual effects are beyond environmental and/or regulatory standards. MAGNITUDE 3 - of the Residual Socio-Economic Effect Negligible No detectable change from existing (baseline) conditions. Low Change is detectable, but has no effect on the socio-economic environment beyond that of an inconvenience or nuisance value. Medium Change is detectable and results in moderate modification in the socio-economic environment. High Change is detectable and is large enough to result in a severe modification in the socio-economic environment. PROBABILITY OF OCCURRENCE - Likelihood of Residual Effect High Likely Low Unlikely LEVEL OF CONFIDENCE 4 - Degree of Certainty Related to Significance Evaluation Low Determination of significance based on incomplete understanding of cause-effect relationships and incomplete data pertinent to the Project area. Moderate Determination of significance based on good understanding of cause-effect relationships using data from outside the Project area or incompletely understood cause-effect relationships using data pertinent to the Project area. High Determination of significance based on good understanding of cause-effect relationships and data pertinent to the Project area. Notes: 1 Significant Residual Environmental Effect: A high probability of occurrence of a permanent or long-term residual effect of high magnitude that cannot be technically or economically mitigated. Significant Residual Socio-economic Effect: A residual socio-economic effect is considered significant if the effect is predicted to be: - high magnitude, high probability, short to medium-term reversibility and regional, provincial or national in extent that cannot be technically or economically mitigated; or - high magnitude, high probability, long-term or permanent reversibility and any spatial boundary that cannot be technically or economically mitigated. 2 The assessment period for the effects assessment includes planning, construction, operation and decommissioning or abandonment phases for the Project, while the assessment period for the cumulative effects assessment includes the above interval as well as the development, construction and operation phases of activities or projects that have previously occurred and those that are planned (publicly disclosed). Page 6-6

7 TABLE Cont d 3 In consideration of magnitude, there is no environmental standard, threshold, guideline or objective for many of the construction/operation issues under evaluation. Therefore, the determination of magnitude of the adverse residual effect often entailed a historical consideration of the assessment of magnitude made by regulators, land authorities, lessees, other stakeholders and the assessment team to adverse effects. The assessment team was also aware of the increasingly stringent societal norms related to environmental effect. 4 Level of confidence was affected by availability of data, precedence, and degree of scientific uncertainty or other factors beyond the control of the assessment team. Ecological context (e.g., levels of existing disturbance; resilience of the receiving environment) is not included in Table However, the ecological context is provided in Section 6.2 for each applicable element. For environmental elements, a significant residual effect has a high probability of occurrence, is permanent or reversible in the long-term and is of high magnitude that cannot be technically or economically mitigated. For socio-economic elements, a residual effect is considered significant if the effect is predicted to be: high probability, high magnitude, short to medium-term reversibility and regional, provincial or national in extent that cannot be technically or economically mitigated; or high probability, high magnitude, long-term or permanent reversibility and any spatial boundary that cannot be technically or economically mitigated. As previously mentioned in Section 6.1.4, mitigation is considered to be the elimination, reduction or control of a project s adverse environmental effects, including restitution for any damage to the environment caused by such effects through replacement, restoration, compensation or any other means. For each environmental and socio-economic residual effect, the effect balance or direction (i.e., determination as to whether the effect is positive or negative) was also established. A positive effect balance is considered to have a net benefit to the environment or socio-economic conditions. A neutral balance is defined as no net benefit or loss to the environment or socio-economic conditions, while a negative balance is considered to be a net loss or detriment to the environment or socio-economic conditions. All significance assessment criteria (e.g., temporal context, magnitude, etc.) were considered by the assessment team for each residual environmental or socio-economic effect. Where appropriate, the key or most influential assessment criteria used to determine the significance of each residual effect are noted. An evaluation of combined adverse residual effects or combined positive residual effects has been conducted for those elements where more than one identified potential adverse effects or positive residual effects may occur at a particular location. The evaluation of the combined effects considers only those residual effects that are likely to occur (i.e., of high probability). A discussion of the combined effects has been included in the significance evaluation to provide further understanding of the overall effect of the Project on the element in question. The extent to which professional judgement of the assessment team was used in the evaluation of significance of potential environmental and socio-economic residual effects is provided for each element. For this Project, the assessment team consisted of discipline experts, the TERA Project Manager, experienced assessment practitioners and senior reviewers. For some elements, the evaluation of significance benefited from a review of select Environmental As-Built Reports and PCEM from previous Enbridge projects that encountered issues/environmental setting similar to the Project. A summary of the significance evaluation for residual environmental and socio-economic effects arising from the construction and operation of the replacement pipeline and associated pipeline facilities is provided in Sections 6.2 to 6.5. Page 6-7

8 6.2 Effects Assessment - Pipeline Construction and Operation Using the assessment methodology described in Section 6.1, the following subsections evaluate the potential environmental and socio-economic effects associated with the construction and operation of the replacement pipeline component of the Project. Environmental and socio-economic elements potentially interacting with construction and operation of the proposed replacement pipeline are identified in Table TABLE ELEMENT INTERACTION WITH PROPOSED PIPELINE COMPONENT Interaction with Pipeline Component Element Construction Operations 1 Physical and Meteorological Environment Yes Yes Soil and Soil Productivity Yes Yes Water Quality and Quantity Yes Yes Air Emissions Yes Yes GHG Emissions Yes Yes Acoustic Environment Yes Yes Fish and Fish Habitat Yes Yes Wetlands Yes Yes Vegetation Yes Yes Wildlife and Wildlife Habitat Yes Yes Species At Risk Yes Yes Human Occupancy and Resource Use Yes Yes Heritage Resources Yes No since surface or buried heritage resources sites, if present, would have been disturbed as a result of construction activities, no interaction is anticipated during operation of the pipelines TLRU Yes Yes Social and Cultural Well-Being Yes Yes Human Health Yes Yes Infrastructure and Services Yes Yes Navigation and Navigation Safety Yes Yes Employment and Economy Yes Yes Note: 1 Activities during operations include aerial patrols, vegetation management and integrity digs. The potential environmental and socio-economic effects associated with the construction and operation of the proposed replacement pipeline, as well as the proposed mitigation measures (including enhancement measures) and resulting potential residual effects are presented in the following subsections for each environmental and socio-economic element as well as for accidents and malfunctions. In addition, an evaluation of significance using the criteria presented in Table for the potential residual effects associated with the applicable environmental and socio-economic elements is also provided. A key consideration in the assessment of the potential effects arising from the operation of the replacement pipeline as well as the potential effects related to accidents and malfunctions during the operations phase, is that the purpose of the construction of the proposed pipeline is to replace the existing Line 3 pipeline and then to decommission the existing Line 3 pipeline. Consequently, the potential effects related to operations and maintenance activities as well as accidents and malfunctions during the operations phase of the replacement pipeline will not result in a net increase in those effects since the decommissioning of the Line 3 pipeline will reduce the need for the presently ongoing operations and maintenance of the existing Line 3 pipeline. Maintenance activities required for the replacement pipeline are expected to be much less than the current maintenance activities required for the existing Line 3. In some cases, due to the relatively high intensity of the maintenance activities (i.e., investigation digs) along the Line 3 pipeline, the overall effects arising from the replacement pipeline will be less than is presently experienced along the Line 3 pipeline. Page 6-8

9 6.2.1 Physical and Meteorological Environment Spatial Boundaries The spatial boundaries used in the effects assessment of the physical and meteorological environment considered one or more of the following areas: the Footprint Study Area (as defined in Section 6.1); and Physical Environment and Soils LSA. A Physical Environment and Soils LSA (see Figures to ) was established to incorporate the area in which the physical and meteorological environment is most likely to be affected by pipeline construction and operation. The Physical Environment and Soils LSA, defined as the ZOI likely to be affected by terrain instability during construction and operation of the replacement pipeline, consists of a 1 km wide band centred on the construction right-of-way centre line (i.e., 500 m on both sides of the construction right-of-way centre line) to incorporate effects that may extend off the Footprint (e.g., water erosion on slopes), and a 500 m buffer around known temporary workspace boundaries along the construction right-of-way. This spatial extent is considered sufficient for consideration of the potential effects to the physical and meteorological environment as a result of the construction and operation of the replacement pipeline. The potential effects are not anticipated to extend beyond the Physical Environment and Soils LSA and, therefore, a Physical Environment and Soils RSA has not been established Physical Environment Context The replacement pipeline route generally encounters flat to undulating topography with slopes encountered at the approaches to watercourse crossings, which may be areas of potential instability (Appendix 2). Bedrock underlying the replacement pipeline route is primarily of Cretaceous age, with the exception of a Tertiary formation in Saskatchewan, from SKP to SKP 473.7, and a Jurassic age formation in Manitoba from SKP to SKP No acid-generating bedrock is encountered along the replacement pipeline route (Mentiga 2014). Elevations along the replacement pipeline route range from m asl in Alberta, from m asl in Saskatchewan and from m asl in Manitoba. No areas of permafrost are expected along the route (NRC 2009) Potential Effects and Mitigation Measures During stakeholder engagement, no potential effects associated with the construction and operation of the replacement pipeline on the physical and meteorological environment were identified by Aboriginal groups, landowners or government agencies (Section 3.0). The potential effects associated with construction and operation of the replacement pipeline on the physical and meteorological environment were identified by the assessment team based in part on PCEM along the previously constructed ACEP and are listed in Table A summary of mitigation measures provided in Table were principally developed in accordance with industry and provincial regulatory guidelines. There are no specific objectives in the Municipal Development Plans (MDPs) of the MD and RMs crossed by the replacement pipeline route that pertain to the physical and meteorological environment. Page 6-9

10 TABLE POTENTIAL EFFECTS, MITIGATION MEASURES AND POTENTIAL RESIDUAL EFFECTS OF PIPELINE CONSTRUCTION AND OPERATION ON THE PHYSICAL AND METEOROLOGICAL ENVIRONMENT Potential Effect Location 1. Terrain instability arising from slumping 1.1 General Moderate to steep Measures slopes and sidehills 1.2 Terrain instability arising from slumping at watercourse crossings Watercourses identified along the route (see Environmental Alignment Sheets) Spatial Boundary 1 Key Recommendations/Mitigation Measures [EPP Reference] 2 LSA Implement the following standard mitigation measures where unstable areas are encountered: slope back construction right-of-way cuts; maintain or re-establish surface and/or subsurface drainage patterns; install drainage and erosion controls such as berms, trench breakers and subdrains; and armour streambanks as per engineering and construction specifications [Section 7.4]. Recontour the construction right-of-way and restore the pre-construction grades and drainage channels. Where restoration of the pre-construction grade is not feasible due to risk of failure of fill on slopes, recontour to grades not exceeding 1:3 (rise over run) or as directed by Enbridge Engineering [Section 7.4]. Monitor areas of potential terrain instability following construction as part of the PCEM program. Monitor slope stability on a routine basis for the life of the pipeline. Conduct remedial work, as needed, to protect pipeline integrity. Monitor the proposed construction right-of-way during operation with regular aerial patrols and after heavy snow melt or heavy, persistent rainfall to identify areas of erosion. Conduct remedial work, as needed, to protect pipeline integrity in a timely manner. LSA All pipeline crossings of watercourses are to be crossed using either trenchless (horizontal directional drill [HDD], bore or punch) or isolated (dam and pump or flume) techniques when not dry or frozen to the bottom. Pipeline crossings may be open-cut if watercourses are dry or frozen to bottom. Vehicles and equipment will use existing crossings or temporary span bridges in open water season on fish bearing watercourses. Under frozen conditions, vehicles and equipment will use either existing crossings, ice/snowfill crossings, or span bridges [Section 2.1.2]. Implement the bank and riparian protection and reclamation measures identified in Table 4 of the Environmental Alignment Sheet Package at all watercourse crossings that were trenched or where disturbance of the bank or riparian area occurred [Section 7.7]. Recontour the bed and banks of the watercourse as close as feasible to their pre-construction profile (slope and height). Take appropriate measures to reduce the risk of sloughing of the streambanks following construction. The Environmental Inspector will determine on-site whether restoration measures in addition to those identified in Table 4 of the Environmental Alignment Sheet Package are needed to stabilize the banks (e.g., soil wraps, brush layers, willow plantings and matting) and promote the restoration of the pre-construction conditions. Obtain recommendations from Enbridge Engineering regarding measures to effectively stabilize the banks. [Section 7.7]. Install temporary berms on approach slopes to watercourses and wetlands, and erect silt fence or an equivalent temporary erosion/sediment control device (e.g., hay bales, coir logs, etc.) near the base of approach slopes to watercourses and wetlands immediately following grading [Details 28 and 29 in Appendix E]. Monitor the temporary erosion control structures on a regular basis and repair, if warranted. [Section 7.2]. Potential Residual Effect(s) Areas of terrain instability may occur as a result of construction activities Topography may be altered at locations where cut slopes are too steep to be replaced to the pre-construction profile without creating areas of instability Areas of slope instability where a trenched crossing method is used at watercourse crossings 2. Changes to the Project caused by the environment For a discussion of the changes to the Project caused by the environment, including the effects of the meteorological environment, refer to Section 6.7. Notes: 1 LSA = Physical Environment and Soils LSA. 2 Detailed mitigation measures are outlined in the Project-specific Pipeline EPP (Appendix 1A). See Section 6.7 Changes to the Project Caused by the Environment Page 6-10

11 Potential Residual Effects The potential residual environmental effects on the physical and meteorological environment associated with the construction and operation of the replacement pipeline (Table ) are: areas of terrain instability may occur as a result of construction activities; areas of slope instability where a trenched crossing method is used at watercourse crossings; and topography may be altered at locations where cut slopes are too steep to be replaced to the pre-construction profile without creating areas of instability Significance Evaluation of Potential Residual Effects A qualitative assessment was considered the most appropriate method to evaluate the significance of potential residual effects on the physical and meteorological environment, due to the lack of quantitative data and accepted standards, guidelines and ecological thresholds. This qualitative assessment relied on the results of previous PCEM programs and the professional judgement of the assessment team. Table provides a summary of the significance evaluation of potential residual environmental effects of the construction and operation of the replacement pipeline on the physical and meteorological environment. The rationale used to evaluate the significance of each of the potential residual environmental effects is provided below. All assessment criteria were considered when determining the significance potential of residual effects, but the most influential assessment criteria were reversibility and magnitude. An evaluation of significance is not required for those potential effects where no potential residual effect is identified. Changes to the Project caused by the environment (i.e., wildfire, floods and severe weather events) are discussed in Section 6.7. TABLE SUMMARY OF EFFECTS CHARACTERIZATION RATIONALE AND SIGNIFICANCE DETERMINATION FOR THE PHYSICAL AND METEOROLOGICAL ENVIRONMENT Potential Residual Effect Criteria Rating Effects Characterization Rationale a) Areas of terrain instability Impact balance: Negative Terrain instability could affect the safety of the pipe and result in surface erosion. may occur as a result of Spatial boundary: Physical Terrain instability as a result of construction activities may extend beyond the construction activities Environment and Soils LSA construction workspace. Duration: Short-term The event causing terrain instability is construction of the pipeline (e.g., grading and rough clean-up). Frequency: Isolated The event causing terrain instability (i.e., construction of the pipeline) is confined to a specific period. Reversibility: Short-term Areas of terrain instability could take up to 1 year to remediate. Magnitude: Low The implementation of the proposed mitigation measures is expected to effectively reduce the potential effects on terrain instability. Probability: Low Terrain instability will likely be avoided by using proven construction procedures. Confidence: High Based on data pertinent to the Project area and the experience of the assessment team. Significance: Not significant There are no situations where there is a high probability of occurrence of a permanent or long-term residual environmental effect on the physical and meteorological environment of high magnitude that cannot be technically or economically mitigated. (b) Areas of slope instability where a trenched crossing method is used at watercourse crossings Impact balance: Negative Spatial boundary: Physical Environment and Soils LSA Duration: Short-term Slope instability could affect the safety of the pipe and water quality of the watercourses. Slope instability, as a result of trenching at watercourses, may extend beyond the construction workspace. The event causing slope instability is construction of the pipeline (e.g., grading, trenching and backfilling during trenched crossing). Page 6-11

12 TABLE Cont d Potential Residual Effect Criteria Rating Effects Characterization Rationale (b) Areas of slope instability where a trenched crossing Frequency: Isolated The event causing slope instability (i.e., construction of the pipeline) is confined to a specific period. method is used at Reversibility: Short to Depending upon the length of time needed to restabilize the affected area. watercourse crossings medium-term (cont d) Magnitude: Low The implementation of the proposed mitigation measures is expected to effectively reduce the potential effects on slope instability. Probability: Low Slope instability will likely be avoided by the installation of erosion protection measures and proper trenched crossing procedures. Confidence: Moderate Based on the experience of the assessment team on previous pipeline projects with similar conditions. Significance: Not significant There are no situations where there is a high probability of occurrence of a permanent or long-term residual environmental effect on the physical and meteorological environment of high magnitude that cannot be technically or economically mitigated. c) Topography may be altered at locations where cut slopes are too steep to be replaced to the pre-construction profile without creating areas of instability Impact balance: Negative Spatial boundary: Physical Environment and Soils LSA Duration: Short-term Frequency: Isolated Reversibility: Permanent Magnitude: Low Probability: High Confidence: High Significance: Not significant Local topographic alteration is considered a detriment to the environment. Alterations in topography may extend beyond the construction workspace. The event causing the alterations in topography is construction of the pipeline. The event causing the alteration in topography (i.e., construction of the pipeline) is confined to a specific period. Alterations in topography resulting from slopes that are too steep to be restored to the pre-construction profile cannot be reversed. The implementation of the proposed mitigation measures is expected to effectively reduce the potential effect of alteration of local topography. Based on data pertinent to the Project area and the experience of the assessment team. Based on data pertinent to the Project area and the experience of the assessment team. There are no situations where there is a high probability of occurrence of a permanent or long-term residual environmental effect on alteration of the physical and meteorological environment of high magnitude that cannot be technically or economically mitigated. Terrain Instability Minor areas of terrain instability may occur along segments of the replacement pipeline route as a result of the proposed construction activities (e.g., trenching, grading and sidehill slope cuts). The impact balance of this potential residual effect is considered negative since terrain instability could affect the safety of the pipe and results in surface erosion. Terrain along the replacement pipeline route is considered to be stable, based on observations and operating experience to-date, of the existing Enbridge pipeline system, including the ACEP, to-date. Construction of the replacement pipeline will comply with industry-accepted practices and measures outlined in the EPP and, therefore, the pipeline is not expected to cause slumping events. The mitigation measures recommended in Table have been found to be effective during construction and reclamation of the ACEP. Similar mitigation measures are planned for the construction of the replacement pipeline. Areas of potential terrain instability will be routinely monitored during aerial patrols over the life of the pipeline and promptly remediated, as needed, to protect pipeline integrity and reduce effects on the environment. The residual effect of terrain instability occurring as a result of planned construction activity is reversible in the short-term and of low magnitude and, consequently, the potential residual effect is not significant (Table , point [a]). Slope Instability Areas of slope instability may occur where a trenched crossing method is used at watercourse crossings. The impact balance of this potential residual effect is considered negative since slope instability could affect the safety of the pipe and water quality of the watercourses. Terrain along the replacement pipeline route is generally level to undulating, although steep slopes are present on the approaches to some water crossings (e.g., Eagle Creek, and the South Saskatchewan, Souris, and Qu Appelle rivers). The placement of HDD entry and exit locations well back from the potentially unstable areas at the crossing of the South Saskatchewan and Souris rivers, and the depth of the drill paths are expected to avoid the effect of terrain instability issues on the pipeline. In the event that an initial HDD is unsuccessful, the HDD will be reattempted (no contingency crossing method is considered). Where other steep unstable slopes Page 6-12

13 are encountered, Enbridge will engage an engineer to develop additional mitigation measures to prevent and control terrain instability during construction. The installation of erosion protection measures at other watercourse crossings will reduce the potential for slumping occurrence. The potential residual effect of slope instability during trenched watercourse crossings is of low magnitude and is reversible in the short to medium-term, depending upon the length of time needed to restabilize the affected area and, consequently, the potential residual effect is not significant (Table , point [b]). Alterations of Local Topography As a result of construction, topography along the replacement pipeline route may be altered at locations where cut slopes are too steep to be replaced to the pre-construction profile. The impact balance of this potential residual effect is considered negative since local topographic alteration is considered a detriment to the environment. Although this unavoidable consequence will be permanent in localized areas and of high probability, the magnitude is considered to be low because the potential residual effects are expected to be within the environmental standards and, consequently, the potential residual effect is not significant (Table , point [c]). Combined Effects on Physical and Meteorological Environment An evaluation of the combined effects considers those residual effects that may interact with each other and are likely to occur. Since the probability of terrain instability occurring due to construction activities and at trenched watercourse crossings is low, an evaluation of combined effects of the pipeline on the physical and meteorological environment is not warranted Summary As identified in Table , there are no situations where there is a high probability of occurrence of a permanent or long-term potential residual environmental effect on the physical and meteorological environment of high magnitude that cannot be technically or economically mitigated. Consequently, it is concluded that the potential residual effects of pipeline construction and operation on the physical and meteorological environment will be not significant Soil and Soil Productivity Spatial Boundaries The spatial boundaries used in the effects assessment of soil and soil productivity considered one or more of the following areas: the Footprint Study Area (as defined in Section 6.1); and Physical Environment and Soils LSA. A Physical Environment and Soils LSA was established to consider the area in which Project construction and operation activities would most likely have an effect on soil and soil productivity. The spatial boundaries of the Physical Environment and Soils LSA are defined as a 1 km wide band centred on the construction right-of-way centre line (e.g., 500 m on both sides of the centre line of the construction rightof-way) and a 500 m buffer around known temporary workspace boundaries along the construction rightof-way. This spatial extent is considered sufficient for consideration of potential effects on soil and soil productivity as a result of the construction and operation of the Project. The Physical Environment and Soils LSA is shown on Figures to Soil Context A variety of surficial deposits occur along the proposed replacement pipeline route. Loam to clay loam textured till is the dominant surficial deposit along the route. Saline till material is common along the central portion of the replacement pipeline route, especially in lower subsoils. Landscapes associated with the till deposits are mostly gently undulating to gently rolling, although, some moderately to strongly rolling slopes also occur. Most of the replacement pipeline route is located in the Dark Brown Soil Zone in Alberta and Saskatchewan while the entire route in Manitoba is located in the Black Soil Zone. Page 6-13