of Contaminated Lands Adjacent to Lead-Zinc Smelter
DUNCAN SLOPE PHASE III and IV
I and II
to Lead-Zinc Smelter in Trail, BC
Cominco Metals Limited
contaminated land adjacent to lead-zinc smelter by capping
with soil suitable for plant growth. Control accelerated
soil erosion and establishment of native vegetation.
Duncan Slope Phase III and IV project area covers approximately
1 ha. The site is located immediately adjacent to the
Phase I and II project
area and was therefore subjected to similar levels
of sulphur fumigation and metal depositions from the
smelter. In 2005 Terra Erosion Control Limited was retained
to develop and implement a reclamation prescription
for this area. Katherine
A. Enns, RPBio., M.Sc., PBiol., Delphinium Holdings
Inc., collaborated in development of the planting
prescription and is using this area as a research site.
March 2006 a sandy-loam soil capping material was placed
to a depth of approximately one meter over the Phase
III area. Prior to soil spreading, lime was applied
to the site to ameliorate the highly acidic native soil
biosolids from the Celgar pulp mill in Castlegar was
used as an organic amendment in the soil capping material
applied to the top 0.3 meters. The quantity of biosolids
used was calculated so as to obtain 7.5 % organic matter
in this surface layer.
soil placement using a small bulldozer, the machine
tracked up and down the slope to create cleat marks
(surface roughness) for seed microsites and rain catchment.
Straw wattles were also installed across the slope to
control surface erosion until grasses became established.
The site was seeded with native grasses, using both
bunch forming and sod forming species, along with legumes.
The seed mix was developed by Dave Polster R.P.Bio of
Polster Environmental Services Ltd.
IV, which was simply the completion of a small area
not finished in March (Phase III), was completed in
variety of native coniferous, deciduous trees and shrubs
were planted in the fall of 2006. Grass/brush mats were
installed around seedlings during planting to help reduce
the composting process the biosolids used on this project
became heavily infested with weed seeds (windrows were
not covered). This resulted in heavy weed growth on
the site, necessitating an intensive hand weeding treatment
in June 2006.
cover was very good in the spring of 2007, which effectively
stopped soil erosion from the site. Survival of the
planted seedlings was, however, very poor.