4.0 Description of Existing Environment
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NANISIVIK NAVAL FACILITY PROJECT SPECIFIC INFORMATION REQUIREMENTS Revision 3 4.0 DESCRIPTION OF EXISTING ENVIRONMENT 4.1 Physical Environment 4.1.1 Atmospheric Environment The north coast of Baffin Island is considered a polar desert. The annual snowfall in the area is approximately 72 cm, and the annual rainfall is approximately 8 cm. Winters temperatures in January and February range from -33 to -36 ºC (minimums), while summer temperatures in June and July range from 6 to 11 ºC (maximums). Relative humidity ranges from 75 to 85 percent throughout the year with generally no more than six wet days a month. The exception to this is in August where there can be as many as 10 wet days in the month. Ice will begin to form in October and will begin to thaw in mid-July. Total darkness occurs from mid-November for two and a half months, ending at the end of January. Total daylight occurs from the beginning of May for three and a half months until the middle of August. The mean freezing index for Arctic Bay is calculated to be 5,200 degree days, and the thaw index is 430 degree days. Although there is climate data for Nanisivik Airport, at elevation 600 m, the Arctic Bay data near sea level is expected to be more representative of the Project site. Air quality information is based on sampling that was conducted when the Nanisivik mine was operating. CanZinco Ltd. operated and monitored three air samplers for heavy metals at the Nanisivik mine between May 1997 and May 2001. One sampler (Sampler AS1) trapped total respirable particulates (TRP), commonly defined as particulates up to 10 microns in size. A total of 17 of 200 samples (8%) exceeded the total suspended particulate concentrations guideline at AS1 between May 1997 and May 2001 (Gartner Lee Ltd. 2003). The two remaining samplers (Samplers AS2 and AS3) trapped all air borne particulates, referred to as total suspended particulates. None of the total suspended particulate concentrations recorded at AS2 between November 1997 and May 2001 exceeded the objectives. None of the concentrations of total suspended particulate concentrations recorded between May 1998 to May 2001 at AS3 exceeded the objectives, and they generally decreased over time (Gartner Lee Ltd. 2003). Noise levels are currently generally low at the Project site since mining operations have ceased and the mine and associated town have been decommissioned. While the mine was operating, the Project site was subject to routine noise from shipping activities to and from the mine and industrial activities related to the mining operation and nearby town site. 4.1.2 Geophysical Environment The geophysical environment of the Project site is detailed in a geotechnical investigation report prepared by Stantec (2010). The surficial geology consists of alluvial fan deposits from Twin Lakes Creek on the western side of the site and beach terrace deposits of sand and gravel. 4.42 Revision 3: July 2013 NANISIVIK NAVAL FACILITY PROJECT SPECIFIC INFORMATION REQUIREMENTS Revision 3 Areas to the south are covered with coarse rock fragments, or talus, accumulated below the mountains that rise above Strathcona Sound. The peninsula separating Nanisivik on Strathcona Sound from Arctic Bay comprises two relatively distinct geological formations within the Borden Rift Basin (Jackson and Berman 2000). The northern portion of the peninsula is underlain by Phanerozoic sedimentary rocks dolomite and shale while the southern half consists of Mesoproterozoic carbonates and basal basalts. At higher elevations the bedrock becomes sandstone quartzite (de Ruiter 1984). During the geotechnical investigation at the Project site, bedrock was not encountered within the depths drilled (Stantec 2010). Soil was predominantly sand (average 56%) with gravel (average 26%). Baffin Island is located within the continuous permafrost zone of Canada (NRCan 2007). Permafrost is reported to reach depths of 600 m in the region. In summer, the active layer has a depth of 1.5 to 2.5 m from the surface (Stantec 2009). Permafrost has been found at depths greater than 430 m in an underground borehole at the Nanisivik mine (Gartner Lee Ltd. 2003). Surface materials such as glacial till and fill are generally frozen from the last week in September until late July, with melt beginning in the first week of June (Stantec 2009). The Project site is relatively flat and was previously developed for the DFO wharf and the Nanisivik mine. The area south of the Project site is dominated by moderately steep high-relief hills with few areas of level ground (Figure 4.1). The hills rise from sea level at the Strathcona Sound to approximately 650 m near the site of the former Nanisivik Airfield. East Twin Lake (Quasaqtoq Lake) is located at an approximate elevation of 372 m (Gartner Lee Ltd. 2003). Soil samples collected at the Project site in 2008 were found to contain concentrations of substances exceeding the Canadian Council of Ministers of the Environment (CCME) Soil Quality Guidelines for Industrial Use (SQGIL) including the following (AECOM 2009c): copper, lead and zinc arsenic and cadmium petroleum hydrocarbon constituents Because of the results of soil sampling in 2008, an abandonment and reclamation plan for the former mine site was developed by Breakwater Resources (Stantec 2009) including remediation of contaminated soils. Petroleum storage tanks used for the Nanisivik mine are being removed from the Project site, along with the tank liners. Petroleum-impacted soils from the site will be remediated. Revision 3: July 2013 4.43 NANISIVIK NAVAL FACILITY PROJECT SPECIFIC INFORMATION REQUIREMENTS Revision 3 4.1.3 Aquatic Environment The closest bodies of water to the Project site include Twin Lakes Creek located along the western site boundary, and Strathcona Sound, on which the Wharf is located (Figure 4.2). Surface water data is plentiful as a result of Water License requirements to operate the former Nanisivik mine. Studies were carried out in Twin Lakes Creek during 1988, 1989 and annually beginning in 1995 through 2000. These studies indicated that metal loadings in Twin Lakes Creek, and ultimately Strathcona Sound, increased as a result of mining activities. The dominant source of metal loadings was located in the west Adid area and resulted from both naturally occurring and anthropogenic sources of sulphides (Gartner Lee Ltd. 2003). Water samples collected from Twin Lakes Creek in 2008 suggested that concentrations of aluminum, cadmium, iron and zinc exceeded CCME Water Quality Guidelines for Freshwater Life (WQGFL). Elevated concentrations of metals in Twin Lakes Creek were linked to source inputs and natural mineralization (runoff from Gossan areas) from elsewhere in the drainage area, and were not linked to source areas at the site (AECOM 2009c). An Environmental Effects Monitoring Program was completed by Jacques Whitford in 2005 and included a water quality component at the water surface and at 10 m depth in the exposure and reference areas of Strathcona Sound. The results of the water quality monitoring indicated that there were no meaningful differences between the exposure and reference areas. Results of the water quality monitoring in Twin Lakes Creek during periods of low precipitation indicated a significant increase in zinc concentrations between the reference station (2 μg/L) and the terminal station (34 μg/L). This increase likely represented the contribution of the mine effluent (Jacques Whitford 2006). It was found that a natural sulfide outcrop located in Twin Lakes Creek produced high loadings of metals including zinc, lead and cadmium. Zinc concentrations likely increased to acutely lethal concentrations to fish and aquatic life during periods of heavy rain. Additionally, domestic wastewater effluent was discharged into Twin Lakes Creek in the vicinity of the former mine site, introducing nutrients and organic material to the water (Jacques Whitford 2006). Shallow groundwater flow was encountered at approximate depths of 0.7 to 2.5 m at the Project site and likely occurred seasonally (AECOM 2009c). Groundwater samples collected at the site had concentrations of cadmium and zinc exceeding the CCME WQGFL (AECOM 2009c). Sediments sampled from Twin Lakes Creek exceeded the CCME Interim Sediment Quality Guidelines (ISQG) for aluminum, cadmium, lead and zinc in nearly all samples collected. Elevated concentrations of metals in Twin Lakes Creek were linked to source inputs and natural mineralization (runoff from Gossan areas) from elsewhere in the drainage area (AECOM 2009c). Revision 3: July 2013 4.45 NANISIVIK NAVAL FACILITY PROJECT SPECIFIC INFORMATION REQUIREMENTS Revision 3 Sediments sampled from Strathcona Sound generally exceeded the CCME ISQG for cadmium, copper, lead and zinc (AECOM 2009b). As part of the Environmental Effects Monitoring Program completed in 2005, none of the measured general chemistry parameters in Strathcona Sound were substantially higher in the exposure area when compared to the reference area (Jacques Whitford 2006). With the exception of zinc, none of the trace metal parameters measured in Strathcona Sound were substantially higher in the exposure area when compared to the reference area. For zinc, the exposure area concentration was 30 μg/L, whereas the reference area concentration was not detectable (<20 μg/L). The maximum tidal range in Strathcona Sound has been reported as 2.5 m (Frederking and Nakawo 1984). Tidal processes in Strathcona Sound were described by BC Research (1975a). Surface currents in Strathcona Sound range from less than 3 cm/s to 29 cm/s and generally move in an easterly direction with prevailing winds. Below surface waters, currents range from approximately 3 m/s to 11 m/s to a depth of 20 m. Below 20 m, currents are weak. Tides measured in Strathcona Sound range from 2.5 m to 3.2 m. Salinities range from 15 to 24 parts per thousand (ppt) in the surface waters (above 10 m) and from 31 to 33 ppt in the deep waters of the Sound (BC Research 1975a).