Section 6.1 Environmental Background - KITSAULT MINE PROJECT ENVIRONMENTAL ASSESSMENT
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KITSAULT MINE PROJECT
ENVIRONMENTAL ASSESSMENT
Section 6.1
Environmental Background
VE51988KITSAULT MINE PROJECT
ENVIRONMENTAL ASSESSMENT
ENVIRONMENTAL BACKGROUND
TABLE OF CONTENTS
6.1 Environmental Background .................................................................................... 6.1-1
6.1.1 Biophysical Setting .................................................................................... 6.1-1
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6.1 Environmental Background
This section of the Application provides a general description of the biophysical setting of
the proposed Project. It describes the existing biophysical environment, including the
surrounding areas within the zone of potential influences of the proposed Project.
The general environment condition at and around the proposed Project area has been
influenced by previous industrial activity. The proposed brownfield Project is a restart of the
former Kitsault mine. The brownfield site originally produced molybdenum in small
quantities dating back to the Second World War. The restart of the former mine would entail
re-opening an existing molybdenum mine that previously operated from 1968 to 1972 and
1981 to 1982. The existing brownfield site includes access roads to the site, mine site
roads, an active power line, an open pit, and approximately 31 million tonnes (Mt) of
previously mined waste rock. The proponent currently holds a valid permit for the brownfield
site from the BC Ministry of Energy and Mines (BC MEM). Following successful completion
of the Environmental Assessment (EA) process, the proponent would pursue an amendment
to their existing mining permit to begin construction and operations.
The proponent has assembled all available historical information and collected substantial
contemporary data prior to conducting a thorough professional analysis of all findings. The
results of this analysis are presented in baseline reports that have been prepared for each
biophysical subject area. Baseline data, findings, and analyses are also incorporated into
each effects assessment of the proposed Project’s biophysical environment, and the
baseline reports appear as appendices in each biophysical environment effects assessment
section or are available as stand-alone documents.
The role and importance of historical data and studies assessing baseline conditions cannot
be over-stated in the EA process. The proponent recognises the critical role of historical,
recent, and contemporary baseline data in presenting a comprehensive and realistic view of
a proposed Project’s environmental background and current environmental conditions. To
this end, the proponent has amassed a growing body of environmental data and land use
information that has helped inform the proposed Project’s evolving design and planning
processes. The proponent will continue to gather baseline data throughout the proposed
Project’s Application process, and will use this information to refine its approaches, plans,
and activities as the proposed Project progresses through the assessment phase.
6.1.1 Biophysical Setting
The Kitsault property is in upland, hilly plateau countryside characterised by thick stands of
timber interspersed with small lakes, meadows, and swamps. The dominant topographic
features are a series of eroded basaltic lava flows that commonly form cliffs up to 100
metres (m) high. Topography rises quickly from tidewater at Alice Arm to an elevation of
600 m above mean sea level (amsl) at the existing Kitsault open pit, and then up to
approximately 900 m amsl on a lava flow that forms a plateau known as Widdzech
Mountain, where the new Process Plant is proposed to be located.
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The climate in the Kitsault area is temperate coastal, verging on rainforest, and is controlled
by four major factors:
Westerly winds cause atmospheric disturbances that cross the area from west to
east;
Proximity to the Pacific Ocean results in moderate temperatures and an abundant
moisture supply;
The North Pacific semi-permanent high-pressure cell controls the seasonal
distribution of precipitation by forcing the major storm tracts to migrate over the area,
moving south during October and north during March; and
The rugged topography creates distinct solar radiation balances and wind
circulations.
The mean monthly temperature values were estimated based on a long-term synthetic
record developed for the proposed Project site. The available site data were correlated to
the concurrent monthly temperature data at Stewart using a simple linear regression
analysis. The resulting synthetic temperature record has a mean annual temperature of
3.2 degrees Celsius (°C), with minimum and maximum mean monthly temperatures of
-6.0°C and 11.6°C occurring in January and July, respectively.
No regional wind speed or relative humidity data are currently available in the Project area,
so the mean monthly values were based on the measured records from site. The mean
annual wind speed is approximately 1.9 metres per second (m/s), with the predominant wind
direction from the east-southeast in winter and north-northeast in summer. The mean
annual relative humidity is approximately 81 percent (%).
The mean annual precipitation for the site is estimated to be 2,000 millimetres (mm) at an
elevation of 650 m, with 45% falling as rain and 55% falling as snow. This estimate was
based on limited site data and long-term regional data, and included consideration of the
calibration results of a watershed model completed for the proposed Project site, which
translates inputs of regional precipitation into corresponding values recorded in the
proposed Project area. The historical record at Stewart was used as input to the watershed
model used to complete the effects assessment.
The landscape is typical of glaciated mountainous terrain with widespread isolated glaciers
commonly found in the upper elevations. During the last glaciation, the area was dominated
by coalescent valley glaciers, which occupied the majority of the landscape, except for the
highest peaks. Alice Arm was the dominant drainage, likely supporting a large valley
glacier. With sea level rise, the fiord at Alice Arm was inundated by the rising sea.
Bedrock is generally blanketed by a few metres of glacial till and commonly overlain by a
layer of peat bog up to 1 m thick. Outcrop in the area, except for the basalt cliffs, averages
less than 1%.
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The bedrock-controlled landscape also contains widespread undulating and hummocky
terrain, which supports localised wetland complexes. Valley bottom positions contain fluvial
sediments associated with the sedimentation along modern channels and fans. On the mid
to upper slopes, local till and colluvial deposits are identified. In general, the surficial
sediments are thin, commonly not exceeding a few metres, except for those locations where
colluvial cones are found. Local bedrock outcropping is common within the regional area.
Surface soils generally do not exceed Canadian Council of Ministers of the Environment
(CCME) (CCME 2002) or BC Contaminated Sites Regulation (BC CSR) (Government of BC
1996) guidelines, except for a small number of outliers. These outliers appear to be both
naturally occurring with non-disturbed soil units and the result of possible influence from
previous mining activities. Deeper in the soil profile, several metals exceed both BC CSR
and CCME guidelines in many locations.
The proposed Project is predominantly within the Lime Creek Watershed, which drains
directly into Alice Arm. The Lime Creek Watershed is approximately 40 kilometres squared
(km2). Lime Creek is a 5th order tributary of Alice Arm. It drains a steep, mountainous
watershed characterised by waterfalls and canyonised valleys. Patsy Creek, a tributary of
Lime Creek, drains into Lime Creek approximately 7.4 kilometres (km) upstream from Alice
Arm and has a drainage area of approximately 4.5 km2. A small portion of the proposed
Project infrastructure is within the Clary Creek Watershed, adjacent and north of the Lime
Creek Watershed. The Clary Creek Watershed drains into the much larger Illiance River
about 1 km upstream of Alice Arm.
The annual hydrographs for the creeks in the proposed Project area typically have a bi-
modal shape, with the highest peak occurring in the spring freshet period and a secondary
peak occurring in the late fall or early winter. The mean annual unit runoff for Lime Creek at
the mouth is 45.7 litres per second per kilometre squared (L/s/km2), for Patsy Creek at its
confluence with Lime Creek it is 45.1 L/s/km2, and for Upper Clary Creek (near Clary Lake) it
is estimated to be 45.1 L/s/km2. The 200-year peak flow values are 140 cubic metres per
second (m3/s), 22 m3/s, and 112 m3/s for Lime Creek at the mouth, Patsy Creek at the Lime
Creek confluence, and Upper Clary Creek, respectively. The respective 10-year 7-day low
flow values are estimated to be 0.08 m3/s, 0.01 m3/s, and 0.06 m3/s.
The streams in the proposed Project area are generally typical of dilute British Columbia
(BC) coastal streams. They have low alkalinity and hardness, slightly acidic to slightly basic
pH, and low nutrient and metal concentrations. Exceptions to this are Lime Creek and Patsy
Creek, as they receive drainage from highly mineralised areas including the existing Kitsault
Pit formed by previous mining operations.
Patsy Creek, downstream of the existing pit, receives runoff from the Kitsault Pit as a result
of historic mining operations. Water quality parameters in Patsy Creek are generally high,
with several parameters consistently exceeding guidelines for freshwater aquatic life. These
parameters include fluoride, nitrite-nitrogen, sulphate, total cadmium, total copper, total
molybdenum, and total zinc.
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Lime Creek, both upstream and downstream of the Kitsault Townsite, receives drainages
from the Lime Creek upstream areas including the existing Kitsault Pit area and from the
tributaries in undisturbed areas. Total cadmium, molybdenum, and zinc concentrations are
generally high with exceedances to guidelines. The set of chemical parameters of elevated
concentrations at these locations is similar to those exceedances in Patsy Creek, indicating
that upstream water quality is likely contributing to the elevated concentrations found in Lime
Creek.
Lake 901 outlet stream water is slightly acidic. Water samples are consistently outside the
CCME (2007) guideline for the protection of freshwater aquatic life (pH 6.5 to 8.5).
Concentrations of total and dissolved aluminum, total cadmium, total iron, and total zinc
exceed BC Ministry of Environment (BC MOE) (2006) guidelines at times. Clary Creek
water parameters are generally within guidelines for the protection of freshwater aquatic life.
Water quality within the Illiance River downstream of where Clary Creek enters is generally
of good quality.
The fish community of lower Lime Creek below an impassable waterfall about 1 km from
Alice Arm is dominated by an anadromous population of Dolly Varden. Mature adults enter
Lime Creek from the ocean in mid to late September. These spawning fish are typically at
least 4 years old and greater than 200 mm long. Large adults are not present in Lime Creek
during the summer months and the only Dolly Varden present in the creek at this time are
young-of-the-year (KITSAULT MINE PROJECT
ENVIRONMENTAL ASSESSMENT
ENVIRONMENTAL BACKGROUND
previous Kitsault mine operations after the road from Kitsault to Clary Lake was built in
1967.
The proposed Project is located within the Meziadin Mountains Ecosection of the Nass
Ranges Ecoregion (Demarchi 1996). Ecologically, the general area falls within six
biogeoclimatic (BGC) units (Banner et al. 1993), including: Coastal Western Hemlock Wet
Submaritime Submontane Variant (CWHws1), Coastal Western Hemlock Wet Submaritime
Montane Variant (CWHws2), Mountain Hemlock Moist Maritime Windward Variant
(MHmm1), Mountain Hemlock Moist Maritime Leeward Variant (MHmm2), Mountain
Hemlock Moist Maritime Parkland Subzone (MHmmp) and Coastal Mountain-heather Alpine
Zone Undifferentiated (CMAun).
The Coastal Western Hemlock (CWH) is the zone of low- to middle-elevation forests
occupying the river valleys of the Coast Mountain Range, and is located below the Mountain
Hemlock (MH) zone. The vegetation of the CWH is dominated by western hemlock (Tsuga
heterophylla), western redcedar (Thuja plicata), and amabilis fir (Abies amabilis). Western
redcedar is more prevalent in the CWHws1, while Sitka spruce (Picea sitchensis) occurs
mainly on alluvial soils. Deciduous trees, red alder (Alnus rubra), and black cottonwood
(Populus balsamifera ssp. trichocarpa) are uncommon and occur mainly on floodplains. The
understorey vegetation on zonal sites is dominated by blueberries (Vaccinium spp.), and
false azalea (Menziesia ferruginea) in the CWHws1 only. A low cover of herbs and a carpet
of feather mosses cover the forest floor.
The MHmm1, the windward variant, occurs on the western slopes of the Coast Mountains,
while the MHmm2 is found on the central and eastern slopes of the Coast Mountains, lying
between the CWH and CMAun zones. Mountain hemlock (Tsuga mertensiana) and
amabilis fir are the characteristic dominant tree species. Yellow-cedar (Chamaecyparis
nootkatensis) occurs in the MHmm1, mainly on seepage sites. Subalpine fir (Abies
lasiocarpa var. lasiocarpa) is absent from the MHmm1, except in areas of severe cold air
ponding, but is widespread in the MHmm2. The understory vegetation lacks diversity; on
zonal ecosystems blueberry species dominate, forming a well-developed shrub layer,
accompanied by a low cover of herbs and a moderate moss layer.
Above the forested MH is a parkland subzone MHmmp, which occupies the transition from
treeline to true alpine tundra. The parkland subzone is characterised by discontinuous
forest, mainly composed of MH, interspersed with subalpine heath, herb meadows and
subalpine wetlands.
Above the parkland subzone MHmmp lies the CMAun, which occurs along the windward
side of the Coast Mountains. At the treeline, the interface between subalpine parkland and
the true alpine, a mosaic of stunted “krummholtz” tree patches and meadows are common
(MacKenzie and Meidinger 2006). On deeper soils or moister sites, herb meadows
consisting of a variety of herbs occur.
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The region supports a wide range of wildlife species and habitat. Common species or
groups that occur throughout the region include ungulates (e.g., moose, mountain goat,
deer), omnivores / carnivores (e.g., grizzly bear, black bear, wolf), furbearers (e.g., marten,
fisher, wolverine), birds (songbirds, wetland birds, raptors, marine birds), and amphibians.
Moose commonly occur throughout the forested areas of BC and are rated as apparently
secure and not at risk of extinction (BC CDC 2011). However, the moose population within
the Nass Wildlife Area has declined significantly from 1,595 moose in 2001 to 517 moose in
2011 (Demarchi and Schultze 2011). Moose winter habitat throughout the region typically
includes the CWHwm, CWHws1, and CWHws. In the proposed Project area, moose winter
on slopes adjacent to the Kitsault River and estuary. Steep, coastal topography and deep
snow in combination with intermediate-aged dense conifer stands limit moose forage and
likely restrict wintering moose to low elevation riparian areas near the coast.
The population of mountain goats in BC is estimated between 39,000 to 65,000 (Mountain
Goat Management Team 2010), of which 16,000 to 35,000 occur in the Skeena Region
(Blood 2000; Côté and Festa-Bianchet 2003; Mountain Goat Management Team 2010).
This species is on the provincial yellow list and is considered apparently secure and not at
risk of extinction (BC CDC 2011). Mountain goats are usually found near escape terrain,
such as rocky bluffs and cliffs that provide good visibility and are generally inaccessible to
predators (Shackleton 1999). Suitable mountain goat habitat is predominantly not found
within 5 km of the proposed Project area. A few goats were observed in low elevation
forested habitat near the Illiance River during summer, suggesting low-elevation forested
habitats are important for goats in the region.
Sitka black-tailed deer is a subspecies of mule deer that occurs in the coastal area of
northwestern BC and Alaska. In BC, they occur in continuous distribution from north of
Rivers Inlet to Portland Canal. The availability of suitable winter range is key to managing
the Sitka black-tailed deer. Winter range is typically associated with old growth conifer
forest (Hanely 1984) at elevations of less than 300 m (Schoen and Kirchhoff 1990). The
proposed Project area does not appear to support a large number of deer during the winter.
The absence of large tracts of mature and old growth conifer stands (structural stage 6 and
7) at lower elevations likely reduces the suitability of the area as winter range for deer.
Grizzly bears are found throughout the majority of BC across a broad elevational range,
from sea level to high alpine regions; an estimated 13,800 grizzlies occur in the province
(Gyug, Hamilton, and Austin 2004). The distribution of grizzly bears is often related to food
supply, with higher densities in areas with abundant food (Hamilton 1987), such as along
streams during salmon runs and on alpine and subalpine slopes when berries are abundant.
Much of the proposed Project site is of moderate value for grizzly bear (MacHutchon 2011).
This is mainly due to the bog / fen complexes northeast of the old Kitsault mine which is of
moderate suitability for grizzly bear. Grizzly bears may occasionally use the area, most
likely in the late summer or fall when food availability declines at low elevations and some
bears move to higher elevations to feed on late phenology graminoids and forbs or
huckleberries and blueberries. There may also be seasonal movement through the area in
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spring as some grizzly bears, particularly adult males, move between the Kitsault River and
the Nass River valley (MacHutchon 2011).
There are two human-created bear habitats within the proposed Project area that are now
well-used by bears. The old Kitsault mine pit was seeded with grass, clover and alfalfa
when the mine was shut down. These seeded areas are now well-used by black bears for
feeding on the graminoids and forbs, particularly in spring. There is a cleared power
transmission line right-of-way (ROW) for the old Kitsault mine that goes over the divide
between Alice Arm and the Nass River valley. This ROW, in places, is thick with berry-
producing shrubs used by both black bears and grizzly bears (MacHutchon 2011).
Furbearers are important both socially and economically to hunters and trappers. The
harvest of furbearers is culturally significant to the Nisga’a Nation and Aboriginal groups.
Six furbearer species (not including bears) were observed throughout the proposed Project
area, including: American marten, American mink, fisher, gray wolf, lynx, and red fox. Of
these, the American marten is of particular importance to local residents, including Nisga’a
Nation trapline holders and Aboriginal groups. American marten use mature and old growth
conifer forest as winter habitat.
Songbirds, wetland birds, raptors, and marine birds occur throughout the proposed Project
area. Areas with the most diverse songbird species communities were located along the
Kitsault / Alice Arm Forest Service Road (FSR) within the MH Biogeoclimatic Ecosystem
Classification (BEC) and within the CWH BEC of the Lime Creek watershed. Two species of
conservation concern occur in the proposed Project area: federally threatened olive-sided
flycatcher and provincially Blue-listed sooty grouse. Olive-sided flycatchers were found
exclusively in the MH BEC zone and generally prefer open coniferous forests near wetlands
or meadows Committee on the Status of Endangered Wildlife in Canada (COSEWIC) 2007;
Altman and Sallabanks 2000). Sooty grouse were found in both the MH and CWH BEC
zones and typically prefer relative open habitat such as shrubby areas, meadows, and open
canopied forests (Zwickel and Bendell 2005) with well-defined ground vegetation layers.
Raptors, in particular northern goshawks, are considered regionally significant as they are
an indicator of forest ecosystem health and are identified in the North Coast Land and
Resource Management Plan (LRMP) General Management Direction (BC ILMB 2005).
There are two subspecies of northern goshawk in BC. A. g. atricapillus is considered secure
and A. g. laingi is provincially Red-listed and federally designated as threatened on
Schedule 1 under Species at Risk Act (SARA). The proposed Project area borders the
Northern Goshawk North Coast Conservation Region and occurs within the possible range
overlap of A. g. laingi and A. g. atricapillus (as per Figure 1 of the Recovery Strategy for the
Northern Goshawk, laingi subspecies; BC MOE 2008). The range of A. g. laingi is thought
to follow the distribution of the CWH and Coastal Douglas-fir (CDF) BGC variants with the
drier CWH variants (CWHds1, CWHds2, CWHms1, CWHms2, CWHws1, CWHws2),
forming the transitional zone where both A. g. laingi and A. g. atricapillus overlap (BC MOE
2008). Northern goshawk nesting habitat typically includes mature to old-growth forests
(structural stage 6 and 7) at elevations below 900 m with high structural diversity, moderate
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canopy closure, large trees, and open understorey with high amounts of coarse woody
debris (Cooper and Stevens 2000; McClaren 2003; BC MOE 2008).
Wetland birds include groups such as diving and dabbling ducks, loons, geese, swans,
shorebirds, and gulls that use lakes, ponds or wetlands for foraging, breeding, and staging
during the year. Overall, relatively few wetland species were observed throughout the
proposed Project area. Breeding was confirmed for six species: Canada goose, Barrow’s
goldeneye, northern shoveler, mallard, Pacific loon, and red-throated loon. Marine birds
include those birds which use coastal waters and shores for life history activities, such as
breeding, foraging, wintering, and migration. Alice Arm provides wintering, staging, and
breeding habitat for marine birds, including 11 species of conservation concern.
Although some amphibians spend the majority of their life cycle in terrestrial areas, they
depend upon wetland habitat for breeding. Four species of amphibians were found in the
Project area: western toad, Columbia spotted frog, long-toed salamander, and
rough-skinned newts. Of these species, the western toad is of conservation concern; it is
provincially Blue-listed and nationally designated as a species of special concern by
COSEWIC and listed under Schedule 1 of SARA. Western toad observations were
concentrated along Alice Arm Road near the port, near Clary Lake and between Clark Lake
and Killiam Lake. Evidence of reproduction was observed for both the Columbia spotted
frog and the long-toed salamander, although not for western toads. Western toads
generally breed in wetlands with open canopy, shallow sloping edges, and muddy substrate
with shallow, warm, and often slow-moving water. The majority of wetlands (classified as
bog-mire complex) are considered not optimal western toad breeding habitat because they
are usually deep and have a steep dropoff into the water from the surrounding terrestrial
vegetation, and cooler water temperatures.
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