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13-018 from OFR6313
13-018 from OFR6313
13-018 from OFR6313
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13-018 from OFR6313
13-018 from OFR6313
13-018 from OFR6313
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  1. Summary of Field Work and Other Activities 2015, Ontario Geological Survey, Open File Report 6313, p.36-1 to 36-8. © Queen’s Printer for Ontario, 2015 36-1 36. Project Unit 13-018. Filling Groundwater Data Gaps in the Niagara Region to Assist Decision-Making Processes J.D. Campbell1 and A.K. Burt2 1 Niagara Peninsula Conservation Authority, Welland, Ontario L3C 3W2 2 Earth Resources and Geoscience Mapping Section, Ontario Geological Survey, Sudbury, Ontario P3E 6B5 INTRODUCTION In 2013, the Ontario Geological Survey (OGS) commenced a three-dimensional (3-D) mapping project focussed on the Quaternary sediments of the Niagara Peninsula (Burt 2013, 2014; see also Burt, this volume). The OGS was responding to Niagara Region and Niagara Peninsula Conservation Authority (NPCA) proposals to address geological framework data gaps. In year 2 of the OGS study (Burt 2014), Niagara WaterSmart funded an OGS–NPCA partnership to address gaps in the hydrogeological regime that had been identified by Source Water Protection studies (Niagara Peninsula Conservation Authority and AquaResource Inc. 2010). Addressing these gaps will inform effective groundwater management in Niagara (Council of Canadian Academies 2009; Figure 36.1). In 2014, 18 groundwater monitoring wells were constructed to study 3 buried-bedrock valley systems that begin at Lake Erie and have aquifer potential (Flint and Lolcama 1986) (Figure 36.2): 1) the Erigan channel, 2) the Chippawa–Niagara Falls channel and 3) the Crystal Beach channel. The monitoring wells were screened in the most transmissive unit as determined during borehole advancement (Burt 2014). Most wells monitor the uppermost bedrock unit with a 3 m screen, although some 1.5 and 4.6 m screens were used, and some wells monitor both sediment and bedrock (Figures 36.3 and 36.4). GEOLOGICAL CONTEXT The Niagara Peninsula is underlain by Ordovician red and green shale below the Niagara Escarpment, relatively resistant Silurian dolostone forming the Niagara Escarpment cuesta and softer black shale and gypsum forming a shallow basin in the central peninsula, and Devonian limestone above the Onondaga escarpment. A series of buried-bedrock valleys, with the potential to host sediment aquifers, dissect the bedrock surface. These valleys are only evident at the ground surface where they cross the escarpments (for more information on bedrock and the buried valleys, see Burt 2013, 2014; see also Burt, this volume). The Quaternary sediment cover across the Niagara Peninsula, the majority of which was deposited after the Late Wisconsinan glacial maximum, has been grouped into a series of regionally identified sediment packages (for more detailed descriptions, representative photographs and summary logs, see Burt 2013, 2014; see also Burt, this volume). The lower drift package, representing the oldest Quaternary sediments recognized to date, consists of stony silt to sand till (e.g., see Figure 36.4: BH13, BH11, BH31 and BH26) with local deposits of interbedded gravel, dirty gravel and diamicton (possibly eskers) (e.g., see Figure 36.3: BH10) and clean glaciofluvial gravel and/or sand (water bearing) (e.g., see Figure 36.3: BH08;
  2. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-2 see also Figure 36.4: BH14). The lower drift package is overlain by a lower glaciolacustrine unit of rhythmically bedded silt and clay deposited in glacial lakes Whittlesey and Warren (e.g., see Figure 36.3: BH32 and BH09). A final ice advance out of the Lake Ontario basin deposited Halton drift, which is dominated by stone-poor to somewhat stony clayey diamicton, often with abundant deformed clay and silty clay laminations, beds and blocks (intraclasts) (e.g., see Figure 36.3: BH32 and BH33; see also Figure 36.4: BH05, BH15, BH11, BH31 and BH26). The Halton unit also includes glaciolacustrine sediments with thin diamicton beds and discontinuous stringers and, more rarely, silt to sand is interbedded with diamicton (e.g., see Figure 36.3: BH08 and BH09). The gravelly sand, sand and silty sand Fonthill ice contact–delta complex, deposited in a re-entrant along the Halton ice margin in the east- central part of the study area, forms an important regional groundwater recharge area. Following the retreat of Halton ice north of the Niagara Escarpment, glaciolacustrine sedimentation once again dominated the region. Upper glaciolacustrine unit rhythmically bedded clay and silty clay blankets the underlying Halton unit across most of the region and, collectively, they form an effective confining layer. Boreholes located close to the Fonthill ice contact–delta complex (e.g., see Figure 36.3: BH10 and BH09) have more silt-rich upper glaciolacustrine unit sediments than observed in surrounding boreholes. Other boreholes are capped with thin sandy sediments deposited in a delta that formed at the mouth of an early Grand River (e.g., see Figure 36.3: BH08; see also Figure 36.4: BH13). Glacial Lake Iroquois formed below the Niagara Escarpment as the ice continued to retreat northward and eastward. There are extensive deposits of Lake Iroquois nearshore sands near Lake Ontario, whereas deeper water silts and clays are found at surface around Niagara-on-the-Lake and north of the main glacial Lake Iroquois shore bluff. Figure 36.1. Work flow from database to decision making, highlighting the importance of establishing a geological framework and hydrogeological regime early in the process (from Oak Ridges Moraine Coalition 2011, p.4).
  3. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-3 Figure36.2.LocationmapshowingNiagaraPeninsulaConservationAuthority(NPCA)monitoringwells,selectedProvincialGroundwaterMonitoringNetwork(PGMN) Programwellsandtheburied-bedrockvalleyaquifersystemstargetedforstudy.
  4. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-4 Figure 36.3. Summary of the lithology, screened interval and June 2015 water levels in monitoring wells constructed along the Erigan channel. Monitoring well locations are shown on the inset map. Numbers on the flow-direction line refer to static water level.
  5. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-5 Figure 36.4. Summary of the lithology, screened interval and June 2015 water levels in monitoring wells constructed along the Chippawa–Niagara Falls channel. Monitoring well locations are shown on the inset map. Numbers on the flow-direction line refer to static water level.
  6. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-6 CURRENT FIELD ACTIVITIES In 2015, NPCA activities focussed on implementing a bedrock valley aquifer monitoring program using the borehole locations constructed in 2014. The NPCA’s program approach (Table 36.1) is based primarily upon protocols developed by the Ministry of the Environment and Climate Change’s Provincial Groundwater Monitoring Program. Single-well response tests were conducted for a minimum of 1 hour using a submersible pump with a maximum flow rate of 20 L per minute (note: wells are 63 mm in diameter, which limits pump options). In 8 of the tests, drawdowns were minimal, ranging from 0.6 to 0.1 m. To increase the drawdown response, a jet pump was used at these higher producing wells, resulting in flow rates between 86 and 170 L per minute (Table 36.2). Equipment limitations prevented even higher rates. In some cases, constant-head injection testing rather than discharge testing was used, as deeper water levels exceeded the pump’s range. Table 36.1. List of tasks for the Niagara Peninsula Conservation Authority groundwater monitoring program. Groundwater Monitoring Program Tasks • Landowner access agreements for sites, including annual insurance requirements • Well development using compressed air to remove drilling mud and estimate a well flow rate • Rustproof, label with agency contact details, and safety flag wells for education and protection • Survey well casings for reference elevation (in metres above sea level (m asl) and Universal Transverse Mercator (UTM) co-ordinates) • Collect and store monthly manual water levels • Install and maintain data-logging pressure transducers for hourly pressure measurements • Complete single-well tests using submersible or jet pumps, by discharge and/or injection methods • Water quality sampling (minimum annually) after well purging and field parameter stabilization Table 36.2. Discharge and injection rates for high-producing wells. Borehole Well Name (and Location) Test Type Rate (L per minute) Water Level Change (m) Erigan channel BH27 Gents Road (Wainfleet) Discharge 20 −0.14 114 −2 BH09 Glynn A Green (Glynn A Green School, Pelham) Discharge 16 −0.7 Injection 161 4 Chippawa–Niagara Falls channel BH13 Concession 1 (Wainfleet) Discharge 20 −0.4 98 −5 BH05 Public Works (Civic Complex, Wainfleet) Discharge 20 −0.1 117 −1.2 BH14 Townline (Townline Road, Wainfleet) Discharge 20 −0.1 Injection 147 3 BH26 Oak Hall (Portage Road, Niagara Falls) Discharge 14 −0.6 Injection 170 1 Crystal Beach channel BH25 College (Niagara Parkway, Fort Erie) Discharge 20 −0.5 86 −4 Other BH01 Glendale (Niagara College, Niagara- on-the-Lake) Discharge 20 −0.2 Injection 208 5
  7. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-7 In 2015, following a second Niagara WaterSmart grant, 5 monitoring wells were constructed in OGS boreholes along the groundwater flow profile of the Upper Welland River Watershed, NPCA’s largest subwatershed (see Figure 36.2). All of these wells were screened in the uppermost bedrock unit. The purpose of the monitors is to characterize the Upper Welland River Watershed groundwater system and serve as “golden-spike” locations for a geochemistry study of the western Niagara Peninsula (see McEwan et al., this volume), complementing existing NPCA wells (Binbrook, W0000287 and W000080) (see Figure 36.2). As part of this study, all 23 monitoring wells constructed in collaboration with the OGS, as well as an additional 5 pre-existing locations along the transects, were sampled by McEwan for a variety of geochemical analyses. PRELIMINARY RESULTS Groundwater elevations in the upper bedrock aquifer show an overall descending trend from Lake Erie to Lake Ontario along the Erigan channel (see Figure 36.3). Channel groundwater tritium concentrations (south of the Welland River) were very low (Table 36.3), suggesting minimal recharge from Lake Erie. The Fonthill ice contact–delta complex forms an important recharge area for the bedrock aquifer system as clearly shown by a 5 m rise in water level beneath it. Groundwater elevations along the Chippawa–Niagara Falls channel clearly show the cone of depression from 40+ years of dewatering the Welland Canal Townline Tunnel (see Figure 36.4). Groundwater tritium concentrations near Lake Erie (south of the Welland River) in this channel were not detectable (see Table 36.3), suggesting a lack of recent recharge. Most waters sampled from the confined bedrock valley aquifers in the fall of 2014 were anoxic, sulphurous and brackish (1000 to 10 000 ppm total dissolved solids), except at the Fonthill ice contact– delta complex. Based on available information, the bedrock valley aquifer systems appear to align well with the Intermediate Regime Sulphur Water System as described by Carter et al. (2014). Initial water chemistry results compare well with those reported previously by the OGS (Hamilton et al. 2011) and further identify naturally occurring groundwater concerns for boron, fluoride and sodium, all of which occur above the Ontario Drinking Water Standards. Table 36.3. Results of tritium analyses for water sampled from boreholes in the Erigan, Chippawa–Niagara Falls and Crystal Beach channels. Borehole Well Name (and Location) Value (tritium units) Erigan channel BH32 Monument (North Shore Drive, Haldimand County) 2.7 BH08 Case Bell (Case Road, Wainfleet) 3.7 BH27 Gents Road (Wainfleet) 1.3 Chippawa–Niagara Falls channel BH13 Concession 1 (Wainfleet) <0.8 BH05 Public Works (Civic Complex, Wainfleet) <0.8 BH14 Townline (Townline Road, Wainfleet) <0.8 Crystal Beach channel BH24 Stevensville (Stevensville Road, Fort Erie) 1.6–2.3 BH25 College (Niagara Parkway, Fort Erie) 2.7
  8. Earth Resources and Geoscience Mapping Section (36) J.D. Campbell and A.K. Burt 36-8 PROJECT PLAN Additional monitoring wells will be constructed adjacent to BH60 (Smith Road) and BH09 (Glynn A. Green School) as overburden aquifers appear to be recharging the bedrock system at these locations. The nested wells will be used to understand the interaction between the 2 aquifer systems. Monitoring program start-up tasks will continue for wells constructed in 2015. Two 2014 monitoring wells will be tested by constant-head injection testing using the jet-pump system in the fall of 2015. Ongoing manual and datalogger water-level monitoring, well maintenance and sampling will continue into 2016. Results of single well response testing will be analyzed to determine hydraulic conductivities. Priority locations for 2016 pumping tests will be identified. A database will be assembled for management of the water level and water chemistry information. Landowners will be notified if the quality of their water exceeds Ontario Drinking Water Standards. Results will be analyzed in collaboration with McMaster University and the OGS. ACKNOWLEDGMENTS Grateful thanks go out to our agency partners for the Niagara WaterSmart funding, as well as their agreeing to host monitoring installations. Partners include Niagara Region, City of Hamilton, Haldimand County, the Township of Wainfleet, Town of Pelham, Town of Fort Erie, City of Welland, City of Niagara Falls, the Niagara Parks Commission, the District School Board of Niagara and Niagara College. In addition to our most excellent drilling contractors, Aardvark Drilling Inc., the groundwater field investigations were a success because of the expertise and dedication of Tom Killingbeck and David Peck (BluMetric), Caitlin McEwan (School of Geography and Earth Sciences, McMaster University) and Lori LaBelle and Trevor White (University of Waterloo). REFERENCES Burt, A.K. 2013. The Niagara Peninsula study: A new three-dimensional Quaternary geology mapping project; in Summary of Field Work and Other Activities 2013, Ontario Geological Survey, Open File Report 6290, p.38-1 to 38-21. ——— 2014. Penetrating Niagara with three-dimensional mapping: in Summary of Field Work and Other Activities 2014, Open File Report 6300, p.32-1 to 32-18. Carter, T.R., Fortner, L., Skuce, M.E. and Longstaffe, F.J. 2014. Aquifer systems in southern Ontario: Hydrogeological considerations for well drilling and plugging; abstract, Canadian Society of Petroleum Geologists, GeoConvention 2014, May 12–16, 2014, Calgary, Alberta, 4p. Council of Canadian Academies 2009. The sustainable management of groundwater in Canada; Expert Panel on Groundwater, Council of Canadian Academies, Ottawa, Ontario, 254p. Flint, J-J. and Lolcama, J. 1986. Buried ancestral drainage between lakes Erie and Ontario; Geological Society of America Bulletin, v.97, p.75-84. Hamilton, S.M., Matheson, E.J., Freckelton, C.N. and Burke, H., 2011. Ambient Groundwater Geochemistry Program: The 2011 Aurora–Orillia study area and selected results for the Bruce and Niagara peninsulas; in Summary of Field Work and Other Activities 2011, Open File Report 6270, p.32-1 to 32-11. Niagara Peninsula Conservation Authority and AquaResource Inc. 2010. Niagara Peninsula Tier 1 water budget and water quantity stress assessment, final report; Niagara Peninsula Source Protection Area, 402p. Oak Ridges Moraine Coalition 2011. Celebrating 10 years of the Oak Ridges Moraine Groundwater Program, 12p., https://oakridgeswater.ca | About Us (download brochure link) [accessed December 3, 2015].
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