Monitoring of Mine Environment

Introduction

Every Environment Impact Statement and mine permit must include a requirement for mine environment before, during, and after the mining process. The government will monitor the environmental parameters, as stated in the permit. The monitoring program should be a part of the company’s overall environmental management system. The monitoring program should be developed using a set of objective commitments of the existing conditions. Monitoring programmes begin with a baseline sampling program performed to characterize the predevelopment environmental conditions. Environmental issues addressed in and management by the plan generally to issues such as land clearing and top soil, water, waste rock, tailings, hazardous wastes, biology (species, health, biodiversity ), dust, noise, and transportation.

The Environmental Monitoring Plan (EMP) needs to provide details about where, when, what, and how often a mining company will monitor the quality of water, air, and soil in the vicinity of the mining project, and the quantity of pollutants in effluents and emissions being released. The EMP must specify how this information will be provided to government decision makers and to the general public so as to ascertain that the mining company is complying all of its promises, and environmental standards and regulations.

Water Quality Monitoring

Monitoring changes in water quality within a mine site is very important for the protection of water quality. A comprehensive water quality monitoring program is essential so as to ensure that the mining company is fulfilling promises in its Environmental Monitoring Plan. According to the Department of Minerals and Energy, Western Australia:

Monitoring of mine site water quality is an essential part of the environmental management of the mining operation. It enables water quality performance to be assessed. Undesirable impacts can thus be detected at an early stage and remedied.

Surface Water Quality monitoring should be conducted for the following:

  • 1. Discharge or seepage existing mine site sources
  • 2. Discharge or seepage exiting the property boundary
  • 3. On-site water bodies and water bodies downstream from the site
  • 4. Background reference sites

According to the IFC/World Bank Group: “Monitoring frequency should be sufficient to provide representative data for the parameter being monitored.”

Groundwater quality monitoring is one of the most important aspects of protecting groundwater resources. This is best achieved by constructing a network of bores. Assessing groundwater quality before an operation commences can set the environmental management needs of a project. Monitoring undertaken during the Environmental Impact Assessment (EIA) process can also establish the baseline data by which the important environmental performance of an operation can be assessed. Undesirable environmental impacts can thus be detected at an early stage and remedied effectively.

Bores are commonly required upstream and downstream, in the direction of groundwater flow to monitor changes in water level and quality across a site and to monitor the performance and stability of tailings facilities. In hard rock areas, bores must be located within geological features that are most likely to transmit groundwater, such as along fault lines, within weathered zones with coarse granular soil or in alluvial sand.

Monitoring bores should be sampled at least once in three months for likely key pollution indicators associated with the project. Surface water chemical monitoring should be conducted for the following.

  • 1. Discharge or seepage exiting on-site sources.
  • 2. Discharge or seepage exiting the property boundary
  • 3. On-site water bodies and water bodies downstream from the sites

Water quality monitoring parameters for mining projects typically include: pH, conductivity, total suspended solids, total dissolved solids, alkalinity, acidity, hardness, cyanide ammonium, sulphates, aluminium arsenic, cadmium, calcium, copper, iron lead, mercury, molybdenum, nickel, and zinc.

A mining company can demonstrate that a particular parameter is not relevant to the mining project. Otherwise, the environmental management plan should require all the above parameters.

Air Quality Monitoring

A mining operation must have an air quality plan to record the emissions of the most significant air pollutants. The selection and location of monitoring equipment should comply with technical assessment and specifications. Weather conditions, topography, residential areas, and wildlife habitat should be considered in order to determine the best location of air quality monitoring equipment. Key issues include:

Air quality monitoring plan as detailed in the EIA, equipment and methods to be used, criteria that were to select the location of the monitoring points, frequency of data collections, whether an independent agency will assess the calibration and implementation of the air quality monitoring plan, whether the results would be available to the public.

Vegetation and Soil Quality Monitoring

Key issues include:

The methods would be used to quantify the excavated or disturbed land, erosion and disturbance of surface soils, etc.

Monitoring Impacts on Wildlife and Habitat

Key issues include:

  • • How are primary effects on fauna, flora, and habitats going to be monitored?
  • • Is any independent agency going to assess the potential effects, including cumulative effects on terrestrial and aquatic wildlife and habitat?

What methods would be used to report and monitoring data?

Monitoring of key species:

Large-scale mining operation activities that could significantly affect the natural functions of terrestrial and aquatic ecosystems. Ideally, an environment monitoring plan for a large-scale mining project would include periodic assessments of impacts on key wildlife species, with support from an independent group of qualified professionals. The baseline section of the EIA should identify wildlife species listed by national or local authorities and/or endemic species.

Key issues include:

• Evaluation of habitat loss, key species as identified in the baseline section, surveys to assess the reduction or alteration of key specific populations, overview' of changes in the ecosystem and potential exposure of key species to hazardous pollutants.

Monitoring habitat loss:

An environmental plan must include plans to perform regular surveys to assess the state of the habitat. The key issues include:

  • • Habitat types should have been adequately identified and mapped previously.
  • • The persons responsible for habitat monitoring. This activity requires qualified independent experts.
  • • Surveys must determine habitat density changes in several locations.
  • • Assessment of the current status of key species based on field work (count and observe species, densities) population.

Monitoring Impacts on Affected Communities

Mineral development can cause serious disruption in local communities related to benefits and costs that may be unevenly shared. The economic gains of a national or a foreign mining corporation do not necessarily contribute to local development. However, environmental degradation affects the livelihood of local people.

Community health:

Key issues include:

  • • Incidence of pollution-related disease and deaths
  • • Assessment of water quality and availability for domestic use, agriculture, and other activities
  • • Results of air quality assessment in populated areas.
  • • Records of regular or episodes of high air pollution
  • • Incidence of alcoholism, prostitution, and sexually transmitted diseases related to the presence of mining workers in the area.

Monitoring of Threats to Public Safety

If a mining project chooses to dispose of its tailings in a w'et tailings’ impoundment, then the failure of the impoundment would constitute one of the most serious threats to public safety. For example, in 1966 in England, the Aberfan disaster w'here a collapse of a coal mine spoil tip claimed the lives of 144 people including 116 school children, mostly between the ages of 7 and 10. The failure of an impoundment would constitute one of the most serious threats to public safety. For this kind of risk, the Environmental Monitoring Plan should include details about how the operation and structural integrity of the tailing’s impoundment would be monitored to promptly detect possible structural problems and prevent potential disasters.

Bibliography

  • 1. Meriam A. Bravante and William N. Holden, Going through the motions: The environmental impact assessment of nonferrous metals mining projects in the Philippines, https://www.tandfonline.com/doi/ abs/10.1080/09512740903128034 (2009).
  • 2. United States Environmental Protection Agency 40 CFR Part 440, Effluent limitation guidelines for metallic minerals mining, https://www.elaw.org/content/us-epa-effluent-limitation-guidelines-metallic- mineral-mining-40-cfr-part-440.
 
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