O
VE R VIE W OFM
E THODOL OG YThe most widespread cause of incidental take associated with mining is the clearing of land.
Because land clearing is essentially the same no matter what metal, mineral, or stone is to be mined, the same basic approach to the calculation of incidental take was followed for all components of mining. In addition, for the activities associated with aggregate pits, there were additional calculations of the within-pit mortality of killdeer and bank swallows.
This section provides an overview of the methodology for calculating the incidental take associated with land clearing for the development or expansion of mines, pits and quarries.
The key data required are:
• Area cleared per year, by broad habitat type and region
• % of area cleared during nesting season
• Density of nesting birds and average clutch size
• % of birds and eggs killed per ha of land cleared during nesting season
Mining activities are undertaken in each province and territory, but the activity is not evenly distributed across the country. In metal and mineral mining, five provinces and territories are dominant. Therefore for each mining sub-sector, detailed analyses were undertaken for the most important jurisdictions, and the results extrapolated to other provinces and territories based on the level of activity in those jurisdictions.
Bird IT mortality was calculated for two general habitat types – grassland/scrubland and forest.
No data were found specifying the amount of area cleared by habitat type – while a reasonable estimate of area cleared could be developed from available data, the author used a combination of his knowledge of the country and discussion with experts to estimate the proportion of each habitat type cleared. In addition, mining for metals and diamonds, and related exploration, is being undertaken in Nunavut and Northwest Territories, and a “sub-arctic habitat” IT figure was derived for this segment of the mining sector.
In the case of metal and mineral mines, the basic calculation was to estimate the number of new mines /major mine expansions per province or territory per year, the associated footprint, and the timing of clearing and type of habitat involved. Information on new mine types and locations was readily available, and information on footprint size was obtained from government and industry personnel, and from literature in some cases.
The nature of the mining process is important from the perspective of incidental take, since the area disturbed to create and operate an open pit mine is more extensive than the area requirements for an underground mine. Moreover, in the classic strip-mining process, a strip of land is cleared, the resource excavated, and the process is repeated on successive strips of land. In contrast, the footprint for the latter type of mine is essentially established when the mine starts up, unless a future expansion takes place. Frequently mines start out as open pit operations and then convert to underground mines once the excavation depth exceeds what is feasible to be extracted from an
Estimating the incidental take associated with exploration was perhaps the most difficult task, in that there was no systematic information available on the amount of area disturbed. Where a deposit is found and there is considerable resource delineation activity, much of this will fall on what turns out to be the mine footprint, should a mine be built. Seasonality also played a major role in the assessment of impacts, as well as discussions with those in the sector regarding the introduction of low impact (and also low cost) methods of exploration.
All aggregate pits, whether they be on public or private land, must be permitted. Most jurisdictions tabulate, or have access to, the area covered by the leases, licences and permits.
However, the area covered under any individual authorization is generally larger than the area of the actual pit, and there was much less information available regarding actual pit area. The Ontario Aggregate Resources Corporation (TOARC) was the only source that was located of annual new pit area. In other jurisdictions, an estimate of area cleared per annum was made based on the term of the licence. Some licence types were only valid for pits of a defined size, and where this was so, this information was considered in estimating annual new disturbance area. In general, there was less information about pits on private land, which is unfortunate since that is where the majority of pits are located.
The seasonality of operations is critical – if most land clearing takes place outside of the nesting season, there will be no incidental take, or certainly negligible amounts. There were no published data on this, and it was through discussions with industry and government staff that an estimate was determined. Reasonable data were available regarding average clutch size however little information was available regarding what proportion of the eggs, young and adult birds are killed when land is cleared during nesting season.
There were also some intangible factors that were taken into account as well. Pits on public land are more closely regulated, and can be inspected by government staff from time to time. This created the impression that operators were less likely to cause incidental take of bank swallows in pits on public land. In addition, the Ontario industry members that were contacted were all aware of the Migratory Bird Convention Act and stated that there were best practices to not operate where there were nesting colonies. Provincial government staff were also aware of the MBCA.
This created the impression that at least some operators to try to avoid causing incidental take. In contrast, pit operators on private land in Alberta operate with fair less constraint. The Alberta Sand and Gravel Association was unable to collect basic operational information from its own members. In addition, none of the interviewees in the province mentioned the MBCA. This created the strong impression that there was considerable IT associated with the operation of existing pits, and a factor was added to account for this.
The within-pit incidental take of killdeer and bank swallows was based on the number of pit licences and permits (as a proxy for the number of pits), an estimate of the number of nests (killdeer) and colonies (bank swallows) in each pit and the number that are destroyed by regular extraction operations.
Incidental Take Associated with Metals &
Minerals
This section covers much of what is considered to be traditional mining, namely the extraction of precious metals such gold and silver, and base metals such as copper, zinc, and nickel. Also
included are coal, uranium, potash, and diamonds. There are numerous mines in Canada, and from 2004 onwards there was a tremendous amount of exploration that ended abruptly in 2008 when commodity prices declined sharply, credit became difficult to find, and the world economy went into recession. However, from the initial discovery of a potentially mineable resource, it will take a minimum of 4-6 years to develop an understanding of the nature and grade of the deposit, to formulate a mine plan and assess of the economics of the project. If the project appears to be able to generate a favourable rate of return, permitting may take several more years, since new mines and major mine expansions require environmental assessments. If a mine passes through the EA process, another 2-3 years are generally required to construct the facilities and bring it into production. Thus, mine development is a long-term undertaking, and while recessions can and do derail the process in some cases (especially when the mine developer is a small company), in most instances, once the resource has reached the permitting stage, mine development will proceed regardless of economic fluctuations.
To give the reader an idea of the number of mines, Figure 1 is a map of active mines and development projects in British Columbia, which has traditionally been among the top three mining provinces. As of 2008, there were 10 active metal mines, 9 coal mines and 35 industrial material mines in the province, with 3 metal mines and 1 coal project in an advanced stage.
Another 10 metal mines, 7 coal mines and two industrial mineral quarries were in the EA process, and there were 118 major exploration projects. The more numerous early stage exploration projects are not shown.
The ratio of active mines to mines in development is low in British Columbia, since the province experienced a hiatus of exploration and development in response to the provincial government’s 1997 decision to bar the development of a promising large mine in northwest B.C. due to its location in an environmentally sensitive zone. As a result, since 1997 there has been only one moderately sized molybdenum mine opened in B.C. (Chalmers, pers. comm.).
While many of the mines are underground, a surprisingly large number are open pit mines. In part this reflects the more appealing economics associated with this approach, including a more rapid mine start-up once all of the permits have been obtained. A review of the ten operating metal mines in British Columbia indicates that 6 are open pit mines, yielding minerals ranging from gold to copper to molybdenum (Source 2009 Map of Major Mining Projects in BC). Of four mines in advanced development, three are open pit projects (see Table 5).
Many of the non-metallic resources are extracted from open pit mines. Of the 9 active coal mines in the province, only one, the Quinsam Coal Mine near Campbell River, British Columbia, is an underground mine. In fact, it is Canada’s last operating underground coal mine – all of the others are open pit/strip mines. Many of the uranium and diamond mines are open pit as well.
Many metal mines are also of the open pit variety, or begin with an open pit process before transitioning to an underground operation once the upper layers of the resource have been removed.
F igure 1. Ins ert map B C major projects maps OF 2009.pdf
There is some level of mining in almost all provinces and territories, with Prince Edward Island being the exception. Figure 2 below shows the distribution of mining expenditures by province and territory in 2008. Ontario attracted the greatest total expenditure, with 20 % of the total.
Saskatchewan and Quebec were close behind, attracting 17.7 and 16.6 % of total expenditures, respectively. Saskatchewan attracted the highest share of mine development expenditures, at 20%. British Columbia attracted 13.6% of total expenditures, and the distribution of spending was notable in that 30% of all deposit appraisal expenditures were in that province. This suggests that B.C. will be the location of a greater proportion of future incidental take than its share of overall expenditures would indicate. Nunavut and Northwest Territories have attracted
significant capital in recent years, and they account for 8.7 and 10.1 % of all expenditures. There is a significant gap between the expenditures in the next most active provinces – Alberta,
Manitoba and Newfoundland and Labrador each attracted between 2-4% of total spending.