| Abstract/Description or Keywords |
The wetlands baseline report presents the results of the wetlands baseline program conducted for the proposed Blackwater Gold Project (the Project) located south of Vanderhoof, British Columbia (BC). The wetlands baseline program was designed to document and describe the distribution, size, composition, and primary functions of wetland resources within and adjacent to the Project area. Description of wetland function incorporates hydrological, biochemical, and ecological/habitat data. This report updates previous versions with 2013 data. The wetland study area includes the mine site, as well as an associated mine site Local Study Area (LSA) and a mine site Regional Study Area (RSA), and four linear features: the water pipeline, mine access road, airstrip, and transmission line. The transmission line is the only linear feature that extends outside the mine site LSA. Two-hundred and ten (210) wetland-related field surveys were completed between summer 2011 and summer 2013 in the wetland study areas. Within the proposed mine site, approximately 575 hectares (ha) (13% by area) were classified as wetlands. Swamp wetlands were the most common wetland class identified in the mine site (9.5%, 421 ha). Provincially Blue-listed wetland ecosystems were found to occupy approximately 39 ha (0.9%) of the mine site. One red-listed and several Blue-listed wetland ecosystems also occurred within the mine site LSA and RSA. Mapped wetland resources comprise approximately 3,122 ha (12%) of the mine site LSA and 5,846 ha (5%) of the mine site RSA. Collected data on hydrological function of wetlands revealed that 50% of the wetlands classified by hydrogeomorphic (HGM) unit were linked basins or hollows. This indicates that wetlands may play an important role in surface water storage, flow moderation, and erosion protection in the Project area. Riparian swamps and linked marsh wetlands provided the highest hydrological functions of the wetlands surveyed. Wetland biochemical function was described using water quality parameters related to nutrient, chemical, and metal concentrations found in the surface water of the sampled wetlands. Overall, baseline water quality results suggest normal conditions for sampled wetlands. Indicators such as low pH, high nutrients (nitrogen and phosphorus), and moderate levels of organic carbon at sampled wetlands were within the natural range of variation for wetland ecosystems in BC. Freshwater aquatic guideline exceedances were detected for total and dissolved metals in all years for some parameters tested, particularly total cadmium, total iron, total zinc, dissolved aluminum, and dissolved iron. These results indicate that naturally elevated metals occur in some sampled wetlands. Wetland ecological function involves the role of wetlands in relation to their surroundings and their ability to support a variety of plant and animal species and communities. Twentyone distinct wetland ecosystems were classified within the wetlands study area. Of the 16 wetland types encountered in the mine site, four are of special concern (Blue-listed) in BC. A total of 318 plant species were identified during the wetland field surveys, four of which are Blue-listed in BC: swollen beaked sedge (Carex rostrata), small-flowered lousewort (Pedicularis parviflora ssp. parviflora), meesia moss (Meesia longiseta), and sickleleaf tomentypnum moss (Tomentypnum falcifolium). One population of T. falcifolium was observed within the mine site boundaries. The Red-listed Hudson Bay clubrush – red hook-moss wetland site association (Wf10) was observed in the mine site LSA and RSA but not inside the proposed mine site. Wetland habitat function relates to the ability of a wetland ecosystem to support wildlife. The sampled wetlands have the potential to support at least 132 wildlife species including 4 amphibians, 64 birds, 10 mammals, 54 odontates, and 7 lepidopterans. Of the 132 wildlife species identified in the wetland study areas, 18 are provincial wildlife species at risk. Seven of these are SARA-listed species including the western toad (Anaxyrus boreas), Yellow rail (Coturnicops noveboracensis), long-billed curlew (Numenius americanus), short-eared owl (Asio flammeus), olive-sided flycatcher (Contopus cooperi), rusty blackbird (Euphagus carolinus), and caribou (Rangifer tarandus). Wildlife habitat functionality values and ranks were developed for a representative sample of wetlands. With the exception of seven wetlands that were ranked high and one ranked low, 48 wetlands were ranked as moderate for wetland habitat function. Wetlands that were ranked high generally had high habitat value for multiple wildlife species. |
