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Hydrogeological Assessment, K2 Wind Project, Proposed Switching Station and Substation at 84595 Tower Line Road

Prepared for: K2 Wind Ontario Limited Partnership Suite 105, 100 Simcoe Street Toronto, ON M5H 3G2

Prepared by: Stantec Consulting Ltd 49 Frederick Street Kitchener ON N2H 6M7

July 21, 2014

HYDROGEOLOGICAL ASSESSMENT, K2 WIND PROJECT, PROPOSED SWITCHING STATION AND SUBSTATION AT 84595 TOWER LINE ROAD

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Table of Contents

EXECUTIVE SUMMARY .................................................................................................................. I

1.0 INTRODUCTION ............................................................................................................. 1.1

2.0 REGIONAL SETTING ....................................................................................................... 2.1 2.1 PHYSIOGRAPHY ................................................................................................................. 2.1 2.2 REGIONAL GEOLOGY AND HYDROSTRATIGRAPHY .................................................... 2.1 2.3 REGIONAL HYDROGEOLOGY ......................................................................................... 2.3

3.0 LOCAL GEOLOGY AND HYDROGEOLOGY ................................................................. 3.1 3.1 GEOLOGY .......................................................................................................................... 3.1 3.2 HYDROGEOLOGY ............................................................................................................. 3.1

3.2.1 GROUNDWATER LEVELS AND FLOW ............................................................ 3.1 3.2.2 GROUNDWATER RECHARGE ........................................................................ 3.2 3.2.3 AQUIFER VULNERABILITY ................................................................................ 3.2

4.0 POTENTIAL FOR CONSTRUCTION AND OPERATIONAL IMPACTS ............................... 4.1 4.1 GROUNDWATER RECHARGE ........................................................................................... 4.1 4.2 CONSTRUCTION DEWATERING ....................................................................................... 4.1 4.3 SPILL CONTAINMENT AND RESPONSE ............................................................................ 4.2

5.0 CONCLUSIONS .............................................................................................................. 5.1

6.0 REFERENCES................................................................................................................... 6.1

LIST OF APPENDICES Appendix A Figures Appendix B Borehole Logs and MOE Water Well Records

LIST OF FIGURES Figure 1 Location Map Figure 2 Physiography Figure 3 Topography Figure 4 Surficial Geology Figure 5 Cross-Section A-A’


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Executive Summary

The K2 Wind Power Project (the Project) is a 270 megawatt wind project currently being constructed in the Township of Ashfield-Colborne-Wawanosh in the County of Huron. The Project is being developed by K2 Wind Ontario Inc. operating as K2 Wind Ontario Limited Partnership, a partnership of Samsung Renewable Energy, Inc., Pattern Renewable Holdings Canada ULC and Capital Power Corporation.

Stantec Consulting Ltd. was retained to complete a desktop-level hydrogeological assessment for the Project’s substation property, a 100 acre (40.5 hectare) property located at the northwest corner of Tower Line and Glens Hill Road (Site). The Site will be used for installation of K2 Wind’s 500 kV substation, where power from the Project’s electrical collector system is gathered for interconnection to the provincial transmission grid. To facilitate this interconnection, Hydro One Networks Inc. (HONI) is installing a switching station on the Site adjacent to the Project’s substation yard, known as the Ashfield 500 kV Switching Station.

The objectives of the hydrogeological assessment were to:

Characterize the geological and hydrogeological conditions underlying the Site and surrounding area.

Evaluate the potential for construction and operational activities at the Site to cause any unacceptable impacts to local groundwater quantity and quality.

The material reviewed as part of the hydrogeological assessment is listed in the references, consisting of a number of regional technical documents as well as some onsite geotechnical reports.

The geology of the Site predominantly consists of deposits of sandy to clayey silt, interpreted to represent a combination of St. Joseph’s Till and finer glaciolacustrine sediments. This hydrostratigraphic unit is referred to as Aquitard 1 (HU-II), which is found to be interspersed with layers of fine sand to sand and gravel beneath the Site. Seasonal groundwater levels were encountered at depths ranging from 0.6 m BGS to 4.6 m BGS. The horizontal movement of groundwater through the overburden is assumed to follow the topographic profile of the Site, with flow traveling from east to west across the property towards Glens Hill Road.

The Site is not deemed to be a Significant Groundwater Recharge Area (SGRA) and onsite surficial soil permeability testing indicates that the Site is characterized by moderate to low groundwater recharge potential. A further review of the literature also indicates that the Site does not overlie any groundwater systems that are deemed to be Highly Vulnerable Aquifers (HVAs), indicating that the aquifers underlying the property are not highly susceptible to impacts


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from potential surface sources of contamination. This is consistent with the results of the onsite investigations which identified that the Site is predominantly underlain by finer grained material.

To date, groundwater dewatering has been minimal at the Site since the start of construction activities in November 2013. This limited level of dewatering has largely been a function of the low volumes of groundwater that have flowed into the excavations from the low permeability deposits of sandy to clayey silt till. Groundwater seepage into the excavations from the sand layers has also been manageable, suggesting that the sand deposits encountered thus far have been limited in their spatial extent within the subsurface and subsequently characterized by finite storage capacity (i.e., the volume of groundwater stored in these sand deposits drains out quickly, with the low permeability glacial till surrounding the sand being incapable of quickly replacing this lost storage). Although an incident occurred onsite where an excavation resulted in the partial flooding of the Site, this incident was caused by the severing of a tile drain lateral and was not the result of groundwater flowing from the native soils of the subsurface to the existing grade.

Overall, groundwater dewatering that occurs onsite will be short-term and isolated to those areas immediately surrounding a given excavation, with the residual effects of this dewatering being reversible. Any potential construction dewatering that may occur onsite is not expected to interfere with the water taking of local offsite private wells given that wells completed within 1 km of the Site are completed in the bedrock aquifer, which is hydraulically separated from the shallow overburden groundwater system by low permeability deposits.

Any accidental spills that potentially occur onsite during the construction and/or operational phases of the development would be localized and involve a small volume of material. Given that the Site is covered by low permeability deposits of sandy to clayey silt till, the downward movement of any spill to the subsurface will be slowed, allowing time for the spill to be mitigated before reaching the shallow groundwater system.


Introduction July 21, 2014

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1.0 INTRODUCTION

The K2 Wind Power Project (the Project) is a 270 megawatt wind project currently being constructed in the Township of Ashfield-Colborne-Wawanosh in the County of Huron. The Project is being developed by K2 Wind Ontario Inc. operating as K2 Wind Ontario Limited Partnership, a partnership of Samsung Renewable Energy, Inc., Pattern Renewable Holdings Canada ULC and Capital Power Corporation.

K2 Wind Ontario Inc. (K2 Wind) has retained Stantec Consulting Ltd. (Stantec) to complete a desktop-level hydrogeological assessment for the Project’s substation property, located at the northwest corner of Tower Line and Glens Hill Road, with a municipal address of 36306 Glens Hill Road (Site). The Site is a 100 acre (40.5 hectares) property currently owned by K2 Wind. The Site will be used for installation of K2 Wind’s 500 kV substation, where power from the Project’s electrical collector system is gathered for interconnection to the provincial transmission grid. To facilitate this interconnection, Hydro One Networks Inc. (HONI) is installing a switching station on the Site adjacent to the Project’s substation yard, known as the Ashfield 500 kV Switching Station.

Specifically, the objectives of the hydrogeological assessment were as follows:

Characterize the geological and hydrogeological conditions underlying the Site and surrounding area.

Evaluate the potential for construction and operational activities at the Site to cause any unacceptable impacts to local groundwater quantity and quality.

All figures referenced in this report are provided in Appendix A, with the Ministry of the Environment (MOE) Water Well Records and borehole logs from onsite geotechnical investigations used to identify the geological and hydrogeological conditions beneath the Site being provided in Appendix B.


Regional Setting July 21, 2014


2.0 REGIONAL SETTING

2.1 PHYSIOGRAPHY

The region containing the Site is occupied by two physiographic regions, which Chapman and Putnam (1984) classifies as the Huron Slope and the Horseshoe Moraines (Figure 2). The Huron Slope consists of beveled clay till plain that extends from the shores of Lake Huron to western limits of the Wyoming Moraine, which lies within the Horseshoe Moraines physiographic region and is located directly to the east of the Site. The till plain of the Huron Slope is occupied by a narrow north-south trending surficial deposit of sand, as well as a ridge of sandy beach deposits that flank the western edge of the moraine, with these soils having been both laid down by the former glacial Lake Warren. The shallow sand deposits are generally characterized by perched groundwater conditions, with wetlands often being present in those sandy areas where topographic depressions exist.

Regionally, the lands containing the Site slope from east to west, sloping from a high of 300 m AMSL on the Wyoming Moraine to a low of 185 m AMSL along the shores of Lake Huron. Similarly, the Site slopes from east to west from a topographic high of 252 m AMSL along the eastern limits of the Site to roughly 241 m AMSL at the western corner of the property (Figure 3). The headwaters of several watercourses originate along the western flank of the Wyoming Moraine, draining westward and eventually discharging to Lake Huron.

2.2 REGIONAL GEOLOGY AND HYDROSTRATIGRAPHY

Geological conditions throughout the region have been documented in investigations completed by Cowan (1974), the Ontario Geological Survey (2003), Waterloo Hydrogeologic, Inc. (WHI) (2004), AMEC Earth and Environmental (2006), Naylor Engineering Associates Ltd. (2007), and the Ausable Bayfield Maitland Valley Source Protection Committee (ABMVSCP, 2011). In summary, the subsurface throughout the region containing the Site is reported to consist of the following key geological formations, with these units being listed from youngest to oldest:

Glaciolacustrine Deposits: Deposits of medium to fine sand and silty fine sand affiliated with the shallow areas of former glacial Lake Warren (i.e., the shoreline) (Figure 4, Unit 9), with the areas where the lake was characterized by deeper waters having glaciolacustrine sediments consisting of laminated to varved silt, clay and minor sand.

Glaciofluvial Deposits: Layers of sand and gravel deposited by sediment-laden meltwater streams discharging from the front of receding glaciers (Figure 4, Unit 7).




St. Joseph’s Till: Silt to silty clay till forming the Wyoming Moraine and extending westward from this feature to the shoreline of Lake Huron, with this till unit commonly being overlain by outwash sands and gravels and various glaciolacustrine sediments. The till is reported to be in the range of 20 m to 25 m thick throughout the region (Figure 4, Unit 5d).

Catfish Creek Till: Dense, stony, sandy silt to silty sand till with little clay content that is commonly referred to as “hardpan” by many water well drillers due to its stoniness and stiffness. The till is generally less than 6 m in thickness, but can reach up to 12 m thick in some areas.

Bedrock: Grey-brown, highly fossiliferous limestone of the Dundee Formation. The Dundee Formation is reported to be in the range of 35 to 45 m thick.

To better understand regional groundwater conditions throughout southwestern Ontario, WHI (2004), developed a three-dimensional conceptual hydrogeological model for lands located within the jurisdictions of the Ausable Bayfield, Maitland Valley, Essex Region, St. Clair Region, Lower Thames Valley, and Upper Thames Valley Conservation Authorities. The model development involved WHI taking geological formations having similar hydrogeological properties, textural characteristics, and stratigraphic position and grouping them together to form hydrostratigraphic units, which were further categorized into aquifers and aquitards. The results of this exercise are presented below, with the key hydrostratigraphic units being identified as follows:

Aquifer 1 (HU-I): A shallow unconfined aquifer system consisting of coarse-grained surficial deposits associated with glaciolacustrine and/or outwash sand deposits. Hydraulic conductivities associated with this aquifer system are reported to be in the range of 10-4 m/s.

Aquitard 1 (HU-II & HU-IV): Fine-grained deposits of silt and clay associated with subglacial till sheets (e.g., HU-II – Rannoch, Stratford Till, Wartburg, St. Joseph’s and Elma Tills; HU-IV – Tavistock and Port Stanley Tills), glaciolacustrine diamicts, and lacustrine clay plains. HU-II and HU-IV are commonly found to be in direct contact with each other and, consequently, are generally considered to represent one hydrostratigraphic unit. Aquitard 1 is extensive throughout the region, ranging from less than one meter to up to 100 m in thickness. This unit is characterized by low permeability, with reported hydraulic conductivities being in the range of 10-6 m/s to 10-8 m/s.




Intermediate Aquifer (HU-III): A confined aquifer system consisting of outwash sands and gravels interbedded within Aquitard 1, with this unit ranging from less than 1 m to 30 m in thickness. This aquifer system is largely found in Middlesex and Elgin Counties and is reported to be absent throughout the region containing the Site (ABMVSCP, 2011).

Aquifer 2 (HU-V): A confined aquifer system consisting of discontinuous deposits of outwash sand and gravel that directly overlie the Catfish Creek Till. The hydrostratigraphic unit is reported to range from less than one meter to 40 m in thickness and is characterized by hydraulic conductivities in the range of 10-4 m/s. However, this aquifer system is reported to be absent throughout the region containing the Site (ABMVSCP, 2011).

Aquitard 2 (HU-VI): Dense, stony, sandy silt to silty sand deposits of the Catfish Creek Till and other older over-consolidated tills such as the Canning Till (silt to clay till). The hydrostratigraphic unit is regionally extensive and is found throughout most of Huron County.

Bedrock Aquifer (HU-VII/VIII): A very good water-yielding aquifer system (MOE, 2003) of variable quality (ABMVSCP, 2011) in which a majority of water supply wells throughout the region are drilled. Hydraulic conductivities associated with this aquifer system are reported to be in the range of 10-5 m/s to 10-6 m/s.

2.3 REGIONAL HYDROGEOLOGY

In general, the groundwater table throughout the region appears to be encountered at its highest levels in those areas where shallow deposits of sand and gravel are located at or near ground surface, with these deposits typically being underlain by sediments characterized by low permeability (i.e., glaciolacustrine deposits of silt and clay and/or the St. Joseph’s Till). Based on mapping presented in Stantec (2012a), the groundwater table is generally shallowest along the western flank of the Wyoming Moraine, corresponding with the ridge of sandy beach deposits affiliated with the former glacial Lake Warren shoreline. The groundwater table becomes progressively deeper moving away from the Wyoming Moraine towards Lake Huron, where groundwater depths of up to 15 m BGS are interpreted to be encountered within the overburden deposits.

Potentiometric surface mapping presented in the Maitland Valley Source Protection Area (SPA) Assessment Report (ABMVSPC, 2011) indicates that groundwater flow within the Bedrock Aquifer (HU-VII / VIII) is to the west and southwest towards Lake Huron, which is interpreted to receive groundwater discharge from this aquifer system. It is assumed that groundwater flow through




the overburden aquifer systems throughout the region are controlled by local variations in topography and that the overall flow is from east to west towards Lake Huron, with some flow moving towards local watercourses.


Local Geology and Hydrogeology July 21, 2014


3.0 LOCAL GEOLOGY AND HYDROGEOLOGY

3.1 GEOLOGY

Figure 4 presents the surficial geology onsite and in the vicinity of the Site as mapped by the OGS (2003), indicating that the Site is covered by a combination of glaciolacustrine-derived deposits of silt to clayey silt till, which are interpreted to represent the St. Joseph’s Till, and glaciolacustrine deposits of fine sand to silty fine sand associated with the beach ridges. Figure 1 shows the location of Cross Section A-A’ (Figure 5), which was constructed using geological information presented in the MOE Water Well Records (WWR) and results obtained from historical onsite geotechnical drilling investigations completed by AMEC (2013; 2006) (Appendix B). Results of the onsite drilling indicates that a 0.2 m to 0.5 m thick layer of topsoil covers the Site, which is underlain by deposits of sandy to clayey silt interspersed with layers of silty fine sand to sand and gravel. The sandy to clayey silt is interpreted to represent a combination of St. Joseph’s Till and the finer glaciolacustrine sediments associated with Aquitard 1 (HU-II). The depths at which the sand layers are encountered beneath the Site occur from 2.0 m BGS (i.e., SUB 06-12) to 19.2 m BGS (i.e., SUB 03-12) and form fairly continuous horizontal layers to smaller isolated pockets within Aquitard 1 (Figure 5). Some surficial deposits of sand were found just beneath the topsoil, but were less than 1.3 m thick and subsequently underlain by the glacial till. Overall, the sand deposits were found to range from 0.6 m to 9.5 m in thickness.

The surface of the Catfish Creek Till (stony, sandy silt to silty sand till) is interpreted to occur at an elevation of approximately 214 m AMSL beneath the Site (27 m to 38 m BGS), which in turn directly overlies the bedrock of the Dundee Formation. The bedrock surface is interpreted to be present at an elevation of approximately 206 m AMSL beneath the Site (35 m to 46 m BGS).

3.2 HYDROGEOLOGY

3.2.1 GROUNDWATER LEVELS AND FLOW

According to the borehole logs completed by AMEC (2013a), groundwater levels measured in the open boreholes at the time of drilling (i.e., December 2012) ranged from 0.8 m BGS to 4.6 m BGS, with groundwater being encountered in both the sandy to clayey silt till (Aquitard 1) and the sand deposits interspersed within this till (Appendix B). To obtain a more representative understanding of stabilized groundwater conditions, water levels were measured from January to June 2013 in monitoring wells installed at HONI 4-12, HONI 6-12 and HONI 12-12. The results of this monitoring found that groundwater levels fluctuated from 0.6 m BGS to 2.7 m BGS (AMEC, 2013b) over this period. Soil colour is also generally understood to be a reliable predictor of groundwater table positioning in the subsurface. Soils characterized by grey colours are indicative of saturated and chemically reducing soil environments, whereas yellowish brown


Local Geology and Hydrogeology July 21, 2014


colours are associated with aerobic and chemically oxidizing conditions. Subsequently, the depth at which soils in the subsurface shift in colouring from brown to grey typically indicates the historical positioning of the seasonal high groundwater table. Beneath the Site, the transitioning of the soil colour from brown to grey was noted to occur at depths ranging from 1.2 m BGS to 3.8 m BGS (Appendix B).

Groundwater present in the sand pockets beneath the Site have been found to be under pressurized conditions, with groundwater within these deposits often rising to ground surface once the lower permeability sandy to clayey silt overlying the sand has been removed.

The horizontal movement of groundwater through the overburden is assumed to follow the topographic profile of the Site, with flow traveling from east to west across the property towards Glens Hill Road.

3.2.2 GROUNDWATER RECHARGE

A Significant Groundwater Recharge Area (SGRA) is defined as an area where the rate of annual recharge to the nearest surficial aquifer system is greater than the average rate of recharge across a given Source Protection Area (SPA) by a factor of 1.15 or more. For the Maitland Valley SPA, in which the Site is located, the average rate of recharge has been established at 182 mm/year (ABMVSPC, 2011). Mapping presented by the ABMVSPC (2011) indicates that the areas within the Site that will be developed are not located on a SGRA, which is not unexpected given that onsite drilling results indicate that the subsurface of the property comprises lower permeability deposits of sandy to clayey silt that form a 2.0 m to 8.8 m thick confining layer above the first sand deposits encountered in the subsurface.

Surficial soil permeability testing performed at the Site by Stantec on June 19, 2014 found the vertical hydraulic conductivity of the sandy silt soils covering the property to be in the range of 3.7 x10-6 m/s to 6.3 x10-6 m/s, indicating that the Site is characterized by moderate to low groundwater recharge potential.

3.2.3 AQUIFER VULNERABILITY

A Highly Vulnerable Aquifer (HVA) is deemed to be an aquifer that can be easily changed or affected by contamination from both human activities and/or natural processes as a result of (i) its intrinsic susceptibility, as a function of the thickness and permeability of overlaying layers, or (ii) by preferential pathways to the aquifer. Mapping presented by the ABMVSPC (2011) indicates that the Site does not overlie any groundwater systems that are deemed to be HVAs, indicating that the aquifers underlying the property are not highly susceptible to impacts from potential surface sources of contamination.


Potential for Construction and Operational Impacts July 21, 2014


4.0 POTENTIAL FOR CONSTRUCTION AND OPERATIONAL IMPACTS

4.1 GROUNDWATER RECHARGE

Under the post-development condition, the majority of the HONI Ashfield switching station and the K2 Wind Substation development areas and the access roads leading to these facilities will largely consist of a gravel base, with the only impervious surfaces being associated with the K2 Wind maintenance and operations building, equipment foundations, and substation building. In addition, the foundations for the transformers, Hydro One switchgear and breakers will be impervious concrete. However, as discussed in the Stormwater Management Report (Stantec, 2013), the total area of impervious surfaces at the Site is expected to increase by only 6% under the post-development condition. Stormwater runoff generated from these impervious surfaces will be directed to a series of drainage ditches, which will convey this runoff to the onsite stormwater management (SWM) facility. During smaller storm events, it is expected that some infiltration will occur as the stormwater runoff flows through these ditches en-route to the SWM facility, lessening the impact of the already minor reduction in recharge potential that will occur at the Site as a result of the development. Overall, it is expected that no detrimental changes in groundwater recharge patterns will occur during the construction and operational phases of the development, resulting in no impact to existing water table conditions or groundwater flow patterns beneath the Site.

4.2 CONSTRUCTION DEWATERING

Any excavations completed on the Site for the purposes of constructing the HONI Ashfield switching station and the K2 Wind Substation may require dewatering to manage the following events:

Groundwater seepage into the excavation in those situations where the shallow aquifer system is encountered.

Precipitation within the construction area, resulting in surface water runoff potentially flowing into the excavation.

Accumulated groundwater and/or surface water in an open excavation following a prolonged construction delay.

To date, groundwater dewatering by Hydro One has been minimal at the Site since the start of construction activities in November 2013, with dewatering volumes not exceeding more than 50,000 L in a given day. This limited level of dewatering has largely been a function of the low volumes of groundwater that have flowed into the excavations from the low permeability deposits of sandy to clayey silt till. Groundwater seepage into the excavations from the sand




layers has also been manageable, suggesting that the sand deposits encountered thus far have been limited in their spatial extent within the subsurface and subsequently characterized by finite storage capacity (i.e., the volume of groundwater stored in these sand deposits drains out quickly, with the low permeability glacial till surrounding the sand being incapable of quickly replacing this lost storage). Although an incident occurred onsite where an excavation resulted in the partial flooding of the Site, this incident was caused by the severing of a tile drain lateral and was not the result of groundwater flowing from the native soils of the subsurface to the existing grade.

Overall, any drawdown that occurs in shallow aquifer system as a result of construction dewatering will be a short-term and isolated to the area immediately surrounding the excavation. The residual effects of the dewatering will also be reversible, given that local groundwater levels will re-equilibrate with the regional water table once the dewatering has been terminated. In addition, any potential construction dewatering that may occur onsite is not expected to interfere with the water taking of local offsite private wells as the MOE WWR indicates that all water supply wells located within one (1) kilometer of the Site are constructed into the Bedrock Aquifer (HU-VII/VIII), which is hydraulically separated from the shallow overburden aquifer system by the low permeability deposits of Aquitards 1 (HU-II) and 2 (HU-VI) (Figure 5).

No groundwater dewatering will occur at the Site during the operations phase of these facilities.

4.3 SPILL CONTAINMENT AND RESPONSE

The potential exists for spills during any construction activity, with the most probable type of spill occurring being attributable to the refueling of major construction equipment. However, as outlined in the Construction Plan Report (Stantec, 2012b), no refueling of vehicles or the storage or use of bulk chemicals or fuels will occur on the project lands and, subsequently, any potential spill that does occur would be localized and involve a small volume of material. Given that the Site is covered by low permeability deposits of sandy to clayey silt till, the downward movement of any spill to the subsurface will be slowed, allowing time for the spill to be mitigated before reaching the shallow groundwater system. In addition, the low permeability deposits of Aquitard 1 (HU-II) and Aquitard 2 (HU-VI) that underlie the Site provide a high level of protection for the Bedrock Aquifer (HU-VII/VIII), which is recognized as being a key water supply aquifer for the majority of private wells located throughout the region.

As per Section 13 of the Environmental Protection Act, all spills that could potentially have an adverse environmental effect, which are outside the normal course of events or are in excess of the prescribed regulatory levels, would be reported to the MOE‘s Spills Action Centre. Details pertaining to the general strategies that will be employed to mitigate any accidental spills are provided in the Construction Plan Report (Stantec, 2012b).




As outlined in the Preliminary Stormwater Management Plan (AMEC, 2012), transformers at the Site will be equipped with a double containment system designed to capture any grease and/or oil that is potentially emitted from these structures.


Conclusions July 21, 2014


5.0 CONCLUSIONS

Based on the hydrogeological assessment, the following conclusions are as follows:

1. The Site is predominantly underlain by deposits of sandy to clayey silt that is interpreted to represent a combination of St. Joseph’s Till and finer glaciolacustrine sediments. This hydrostratigraphic unit is referred to as Aquitard 1 (HU-II), which is found to be interspersed with layers of fine sand to sand and gravel beneath the Site. Aquitard 1 extends to the top of the Catfish Creek Till (i.e., Aquitard 2; HU-VI) that in turn overlies bedrock of the Dundee Formation.

2. In general, the sand layers are found to occur at depths ranging from 2.0 m BGS to the termination depth of the boreholes (i.e., 19.2 m BGS) and form fairly continuous horizontal units to smaller isolated pockets within Aquitard 1. Some surficial deposits of sand are found just beneath the topsoil, but are less than 1.3 m thick and subsequently underlain by the glacial till. Overall, the sand deposits are found to range from 0.6 m to 9.5 m in thickness.

3. Seasonal groundwater levels being encountered at depths ranging from 0.6 m BGS to 4.6 m BGS. Groundwater present in the sand deposits beneath the Site have been found to be under pressurized conditions, with groundwater within these deposits often rising to ground surface once the lower permeability sandy to clayey silt overlying the sand has been removed.

4. The horizontal movement of groundwater through the overburden is assumed to follow the topographic profile of the Site, with flow traveling from east to west across the property towards Glens Hill Road.

5. The Site is not deemed to be a Significant Groundwater Recharge Area (SGRA). Surficial soil permeability testing performed at the Site indicates that the sandy silt soils covering the property to be in the range of 10-6 m/s, indicating that the Site is characterized by moderate to low groundwater recharge potential.

6. The Site does not overlie any groundwater systems that are deemed to be Highly Vulnerable Aquifers (HVAs), indicating that the aquifers underlying the property are not highly susceptible to impacts from potential surface sources of contamination.

7. The proposed development of the Site is expected to cause no detrimental changes in groundwater recharge patterns and, subsequently, cause no impact to existing water table conditions or groundwater flow patterns beneath the Site.


Conclusions July 21, 2014


8. To date, groundwater dewatering has been minimal at the Site since the start of construction activities in November 2013. Overall, groundwater dewatering that occurs onsite will be short-term and isolated to those areas immediately surrounding a given excavation, with the residual effects of this dewatering being reversible.

9. Any potential construction dewatering that may occur onsite is not expected to interfere with the water taking of local offsite private wells as the MOE WWR indicates that all water supply wells located within one (1) kilometer of the Site are constructed into the Bedrock Aquifer (HU-VII/VIII), which is hydraulically separated from the shallow overburden aquifer system by the low permeability deposits of Aquitards 1 (HU-II) and 2 (HU-VI).

10. Any accidental spills that potentially occur onsite during the construction and/or operational phases of the development would be localized and involve a small volume of material. Given that the Site is covered by low permeability deposits of sandy to clayey silt till, the downward movement of any spill to the subsurface will be slowed, allowing time for the spill to be mitigated before reaching the shallow groundwater system. In addition, the low permeability deposits of Aquitard 1 (HU-II) and Aquitard 2 (HU-VI) underlying the Site provide a high level of protection for the Bedrock Aquifer (HU-VII/VIII), which is recognized as being a key water supply aquifer for a majority of private wells located throughout the region.


References July 21, 2014


6.0 REFERENCES

AMEC Environment and Infrastructure (AMEC). 2013a. Draft Report – Geotechnical Investigation, Proposed HONI Switching Station and Substation, K2 Wind Project, Ashfield-Colborne-Wawanosh Township, Huron County, Ontario, Canada. Project No. SW0812016, February 1, 2013.

AMEC Environment and Infrastructure (AMEC). 2013b. 3-Month Groundwater Levels at Proposed K2 Wind Project, Huron County, Ontario. Project No. SW0812016, June 28, 2013.

AMEC Environment and Infrastructure (AMEC). 2012. Preliminary Engineering Report, Stormwater Management Plan for the Project Substation, K2 Wind Power Project, Ashfield-Colborne-Wawanosh Township, Huron County, Ontario, Canada. Project No. TC 124202, July 2012.

AMEC Earth and Environmental (AMEC). 2006. Geotechnical Investigation, Kingsbridge Wind Farm Phase II, Proposed Wind Power Plant, 84595 Tower Line Road, Kingsbridge, Ontario. Project No. SW0206004, June 2006.

Ausable Bayfield Maitland Valley Source Protection Committee (ABMVSPC). 2011. Maitland Valley Source Protection Area Assessment Report – Amended May 2011. May 30, 2011.

Chapman, L.J. and D.F. Putnam, 1984. The Physiography of Southern Ontario. Ontario Geological Survey Special Volume 2, 270 pp.

Cowan, W.R. 1974: Quaternary Geology of the Wingham and Lucknow Areas, Southern Ontario; p.189-191 in Summary of Field Work, 1974, by the Geological Branch, edited by V.G. Milne, D.F. Hewitt, and K.D. Card, Ontario Div. Mines, MP59, 206p.

Naylor Engineering Associates Limited (NEA). 2007. Geotechnical Investigation, Kingsbridge Wind Project – Phase 2, Township of Ashfield-Colborne-Wawanosh, Huron County, Ontario. Project No. 5268G9.R01, March 2007.

Ontario Geological Survey (OGS). 2003. Surficial Geology of Southern Ontario.

Stantec Consulting Limited (Stantec). 2013. Stormwater Management Report, K2 Wind Power Project. June 2013.

Stantec Consulting Limited (Stantec). 2012a. Hydrogeological Assessment in Support of Renewable Energy Approval Application for Short-Term Non-Recurring Water Taking – K2 Wind Power Project. November 2012.


References July 21, 2014


Stantec Consulting Limited (Stantec). 2012b. K2 Wind Power Project Construction Plan Report. November 2012.

Waterloo Hydrogeologic, Inc. (WHI). 2004. Six Conservation Authorities FEFLOW Groundwater Model – Conceptual Model Report. December 2004.


Appendix A Figures

LAKEHURON

SITE LOCATION

Blyth Road

Harriston Road

Bruce Road 86

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HONI 06-12HONI 07-12

HONI 08-12

HONI 09-12

HONI10-12

HONI11-12

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Figure No.

Title

Site Plan1

K2 Wind Ontario Limited PartnershipK2 Wind Power ProjectProposed Switching Station and Substation

July 2014160960902

Notes

Legend

1.

2.

3.

4.

Coordinate System: NAD 1983 UTM Zone 17N

Base features produced under license with the Ontario Ministry of Natural Resources © Queen's Printer for Ontario, 2013.

Orthoimagery © First Base Solutions, 2010.

MOE water well locations are approximate and have been positionedbased on published UTM coordinates.

0 125 250m

1:5,000

"

³ Infiltration Monitoring Location (Stantec, 2014)

"́ Monitoring Well (AMEC, 2012)

"́ Borehole (AMEC, 2012)

"² Monitoring Well (AMEC, 2006)

"² Borehole (AMEC, 2006)

%

*

* Test Hole (AMEC, 2006)

"¹ MOE Water Well

Site Boundary

Cross-Section Location

Watercourse

Waterbody

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Figure N o .

TitlePhysiography2

K2 W in d On ta rio Lim ited Pa rtn ershipK2 W in d Po w er Pro jec tPro po sed Sw itc hin g Sta tio n a n d Sub sta tio n

July 2014160960902

Notes

Legend

1.2.

3.

Co o rdin a te System : N AD 1983 U TM Zo n e 17NBa se fea tures pro d uc ed un der lic en se w ith the On ta rio Min istry o f N a tura l Reso urc es © Queen 's Prin ter fo r On ta rio , 2013.Cha pm a n , L.J. a n d Putn a m , D.F. 2007. Physio gra phy o f so uthern On ta rio ; On ta rio Geo lo gic a l Survey, Misc ella n eo us Relea se—Da ta 228.

0 375 750m

1:15,000

"² Drive-Po in t Piezo m eter (Sta n tec , 2014)Site Bo un d a ryRo a dW a terc o urseW a terb o d yPhysio g ra phic Reg io n Bo un d a ry

Physiography14: Bea c hes8: Bevelled Till Pla in s3: Spillw a ys2: Till Mo ra in es

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Clien t/Projec t

Figure N o.

TitleTopography3

K2 W in d On ta rio Lim ited Pa rtn ershipK2 W in d Pow er Projec tProposed Sw itc hin g Sta tion a n d Sub sta tion

July 2014160960902

Notes

Legend

1.2.

3.

Coordin a te System : N AD 1983 U TM Zon e 17NBa se fea tures prod uc ed un der lic en se w ith the On ta rio Min istry of N a tura l Resourc es © Queen 's Prin ter for On ta rio, 2013.Topogra phy derived from the Southw estern On ta rio Orthophotogra phy Projec t (2010) - Digita l Eleva tion Model © Queen ’s Prin ter for On ta rio, 2010.

0 500 1,000m

1:20,000

"² Drive-Poin t Piezom eter (Sta n tec , 2014)Site Boun d a ryRoa dTopog ra phic Con tour (m AMSL)W a terc ourseW a terb od y

Ground Surface Topography (mAMSL)295273259245231217

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Client/Project

Figure No.

Title

Surficial Geology4

K2 Wind Ontario Limited PartnershipK2 Wind Power ProjectProposed Switching Station and Substation

July 2014160960902

Notes

Legend

1.

2.

3.

4.

Coordinate System: NAD 1983 UTM Zone 17N

Base features produced under license with the Ontario Ministry of Natural Resources © Queen's Printer for Ontario, 2013.

Ontario Geological Survey 2010. Surficial geology of Southern Ontario; Ontario Geological Survey, Miscellaneous Release--Data 128-REVISBN 978-1-4435-2483-4

MOE water well locations are approximate and have beenpositioned based on published UTM coordinates.

0 375 750m

1:15,000

"² Drive-Point Piezometer (Stantec, 2014)

"¹ MOE Water Well

Site Boundary

Road

Watercourse

Waterbody

Surficial Geology20: Organic deposits

19: Modern alluvial deposits

9: Glaciolacustrine deposits (fine sand)

7: Glaciofluvial deposits (sand & gravel)

5d: Glaciolacustrine-derived silty to clayey till(St. Joseph's Till)

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TOPSOIL

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TOPSOIL

TOPSOILTOPSOIL

FINE SAND

FINE SAND

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SANDY SILT

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

SANDY SILT

SANDY SILT

SANDY SILT

SANDY SILT

SILTY SAND

CLAY, SOFT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILTCOARSE SAND

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

CLAYEY SILT

LMSTN, HARD

CLAY, STONES

CLAY, STONES

HARDPAN, STONES

LMSTN, MED-GRAINED

FINE TO MEDIUM SANDMEDIUM TO COARSE SAND

TOPSOIL

TOPSOIL

FINE SAND

SILTY CLAY

SANDY SILT

SANDY SILT

SILTY CLAY

CLAYEY SILT

CLAYEY SILT

HO

NI 1

1-1

2 (O

S 6

3m)

MEDIUM TO COARSE SAND

185 185

190 190

195 195

200 200

205 205

210 210

215 215

220 220

225 225

230 230

235 235

240 240

245 245

250 250

255 255

260 260

265 265

LegendJuly 2014

160960902Client/Project

K2 Wind Onta rio Lim ited Pa rtnershipK2 Wind Power ProjectProposed Switching Sta tion a nd Sub sta tion

Figure No.5

T itleCross-Section A-A'

0 100 200m

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Notes1.

2.3.

10x V ertica l Exa ggera tion

Eleva

tion (

mAMS

L)

Elevation (mAMSL)AWEST

A'EAST

1:4,000

Sa nd

2807

874 (

OS m

)

Well ID (Offset)

Stra tig ra phy

Wa ter LevelWell Screen

T opsoilGla ciola custrine a nd /or Gla ciofluvia lSa ndHU -II (St. Joseph's T ill a nd Gla ciola custrineSilt a nd Cla y)HU -V I (Ca tfish Creek T ill)HU -V II/HU -V III (Bed rock - Dund eeForm a tion a nd Detroit Rock Group)


Appendix B Borehole Logs and MOE Water Well Records

hydrogeological assessment, k2 wind project, proposed switching station and substation ...€¦ ·...

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