Language selection

Archived Content

Information identified as archived is provided for reference, research or recordkeeping purposes. It is not subject to the Government of Canada Web Standards and has not been altered or updated since it was archived. Please contact us to request a format other than those available.

Voisey's Bay Mine and Mill Environmental Assessment Panel Report

5 Air Quality

The main sources of the Project's effects on air quality would include dust generated in the open pit and along haul roads, and emissions from vehicles and power generators. VBNC's baseline studies consisted of meteorological measurements taken at two locations at Edward's Cove and Camp Pond, and a series of air quality studies measuring total suspended particulates, dustfall, nitrogen oxides and sulphur dioxide. VBNC characterized the existing air quality in the Voisey's Bay area as "relatively pristine." This was consistent with VBNC's observation that the site is far from any significant sources of air pollution.

To mitigate the Project's effects on air quality, VBNC plans to

  • generate power efficiently, using exhaust gas heat recovery systems, a preventive maintenance program and other tools;
  • use low sulphur fuels;
  • apply water and dust-reducing agents to haul roads, and take other proactive measures to manage dust;
  • promptly reclaim disturbed areas to reduce wind erosion;
  • use dust collectors and scrubbers in the milling process; and
  • use closed conveyors and transfer points.

In addition, the Environmental Protection Plan will include noise control measures, but these are not specified in the Environmental Impact Statement (EIS).

In predicting residual air quality impacts, VBNC looked at four of the six so-called "common air pollutants": total suspended particulates, sulphur dioxide, nitrogen dioxide and carbon monoxide. The only aspect of toxic air pollutants it addressed was the contribution of heavy metals in dustfall to possible contaminant uptake by plants, animals and humans. VBNC quantified the Project's maximum annual emission of carbon dioxide, one of the most significant greenhouse gases. It also briefly addressed potential microclimate changes in areas of direct physical disturbance.

VBNC modelled noise contours for various sources, both separately and in combination, and then addressed the implications of these predicted noise levels for individual valued ecosystem components (VECs), such as birds.

According to the modelling results, the Project would meet both the provincially regulated standards and the federal maximum desirable objectives for air quality at the Claim Block boundary in all time periods. Within the boundary, air quality would also easily meet these standards, with the exception of short-term particulate matter, which could exceed provincial standards within 2 to 3 km of the open pit during open pit mining.

The Project's annual contribution of carbon dioxide is estimated to represent an increase of 1.2 percent in the total annual emissions of Newfoundland and Labrador, which are currently 4 percent of the Canadian total.

VBNC therefore predicts that residual air quality effects would be minor (not significant) during construction and operation because elevated levels of air pollutants would either fall within regulated standards or be confined to a limited area within the Claim Block, and would be of short duration. The company considers the Project's carbon dioxide emissions to be insignificant in comparison to national or global totals.

VBNC proposes to monitor emissions and ambient air quality. This would presumably be compliance monitoring, to be reviewed by the Newfoundland Department of Environment and Labour (NDOEL). If required, further mitigation measures could include upgraded dust collection systems or scrubbers and changes in dust suppression processes.

5.1 Baseline Information, Modelling and Regulatory Requirements

VBNC used two different models developed for the US Environmental Protection Agency to predict air quality impacts from point sources (for example, the open pit and the power generators) and from linear sources (the haul roads). The models used information about emission sources, site activities, equipment specifications, fuel specifications and emission controls; hourly meteorological data from the Camp Pond weather station; and local terrain data.

The Province regulates ambient air quality through the Air Pollution Control Regulations under the Environment Act. Schedule B to these regulations sets standards for air quality that must be met at the boundary of an industrial site. In an urban setting, this would generally be the property line. Within that boundary, air quality falls within the purview of the provincial Occupational Health and Safety Regulations.

NDOEL asserted that VBNC's baseline air quality studies and air modelling were not carried out in accordance with departmental policies and protocols, so they did not accurately represent either existing or future conditions. NDOEL was concerned that worst case scenarios (for example, maximum equipment usage or upset conditions) were not modelled. VBNC replied that it did not model upset conditions, such as baghouse ruptures, because process control systems would detect the breakdown and immediately shut down the system. It also said that modelling scenarios were "worst case" in the sense that they assumed least favourable weather conditions.

NDOEL also stated that the Claim Block boundary was not an appropriate "property line" with respect to meeting point-of-impingement air quality standards for two reasons. First, project employees would be living on site; therefore, air quality near the accommodations complex must meet the higher standards set by the Air Pollution Control Regulations to ensure health protection, rather than the somewhat lower standards set by the Occupational Health and Safety Regulations. Second, the Claim Block also includes a large area, beyond the actual work site, in which air quality should remain unaffected.

At the hearings, VBNC confirmed that it would meet all regulatory requirements, including data collection and dispersion modelling requirements, and the air quality criteria established by the Air Pollution Control Regulations at the accommodations complex. The Province has indicated that it would negotiate a more appropriate boundary for compliance than the edges of the Claim Block. This boundary would adhere more closely to the locations of Project facilities and activities. The permit process would also establish and enforce ambient air quality compliance monitoring.

The Panel is confident that the baseline information and modelling results were sufficient for environmental assessment purposes and concludes that the current regulatory system will provide for an appropriate level of compliance monitoring.

5.2 Dust Management

The sources of suspended particulates from the Project would include land clearing and site preparation, blasting and other activities in the open pit, wind erosion from rock and overburden storage areas, operation of the crusher plant and conveyors, truck haulage along unpaved roads, concentrate loading at the port, combustion of fuel to operate vehicles or to generate power or heat, and underground mining activities. Depending on the concentrations, suspended particulates can cause or aggravate respiratory problems or reduce visibility. The particulates may also carry persistent contaminants, such as heavy metals or toxic chemicals, that will eventually settle out onto soil, water or plants.

Of all these sources, VBNC estimates that the open pit, truck haulage, the hot water boilers and the power generators would contribute the largest amount. Blasting was not considered to be a key factor in causing ambient air quality impacts, except for very short periods. It was not included in the air quality modelling, although its contributions through dustfall to the movement and accumulation of contaminants were taken into consideration in the contaminants modelling.

Many people addressed dust deposition issues in connection with watercourses, such as Reid Brook. Some Inuit presenters also expressed concern that airborne particles would be deposited on the surface of the snow and could then be transported long distances by wind-driven snowdrift.

The Panel concludes that dust management should be an essential component of VBNC's environmental management throughout the life of the Project, and that it is an area to which VBNC must vigorously apply its policy of continuous improvement.

5.3 Emission Reduction

Under the Canadian Environmental Protection Act (CEPA), the federal government has established ambient air quality objectives at three levels. The most stringent is termed the maximum desirable level. This objective is intended to prevent degradation of air quality in pristine or unpolluted areas. The Panel believes this clearly applies to the Voisey's Bay area, and notes that the CEPA objective is stricter than the provincial ambient air quality standards for sulphur dioxide and total suspended particulates.

The Panel understands that ambient air quality standards would be met, often easily, except within a fairly small area of the Claim Block. This is, however, no reason for complacency. The Panel believes that VBNC should make every effort, through the use of best environmental management practices, a vigorous energy conservation program, and appropriate pollution control equipment, to continuously reduce emissions at source throughout the life of the Project and to minimize the contributions of greenhouse gases. There are four main reasons behind this conclusion.

  • The Voisey's Bay area has nearly pristine air quality. In keeping with the national policy reflected in the maximum desirable objectives for air quality, the goal should be to keep degradation to an absolute minimum.
  • Air emissions would be a potential source of adverse impacts to watercourses in the area and particularly to Reid Brook.
  • Like other northerners, Labrador residents are already seeing the effects of airborne contaminants travelling long distances, and they would need to be reassured that the Project would not add to their concern.
  • While the contribution of the Project to regional or global atmospheric problems, such as acid precipitation and climate change, may seem insignificant, these problems are in fact caused by the combined effects of many seemingly insignificant contributions.

There are no regulated emission standards for carbon dioxide. However, if the Kyoto Protocol to the United Nations Framework Convention on Climate Change is ratified, Canada will have made an international commitment to reduce its greenhouse gas emissions to 6 percent below 1990 levels over the period 2008-2012. This reduction will be no easy task, given that Canada's emissions are projected to be 19 percent above 1990 levels by the year 2010. The Panel therefore believes that VBNC has a responsibility to minimize carbon dioxide emissions through careful attention to energy conservation, which will also help maintain ambient air quality.

Recommendation 6

The Panel recommends that VBNC, as part of its environmental protection plan, do the following.

  • VBNC should develop a dust management plan that incorporates best management practices derived from other mining and related operations, to minimize the creation and mobilization of dust. This plan should include preventive measures, such as appropriate speed limits for truck traffic on haul roads and dust suppression techniques.
  • VBNC should develop a comprehensive energy conservation program, to prevent air pollution effects by reducing the combustion of fossil fuels. The program should include an energy review of the planned Project design before construction starts.