Const Materials Extraction

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CONSTRUCTION MATERIALS EXTRACTION-

QUARRIES

Environmental issues during the operational, construction, and decommissioning phases of construction materials extraction

primarily include the following:

Air Emissions

Noise and Vibrations

Water

Waste

Land Conversion

Air Emissions

The primary air pollutants are dust and vehicle emissions.


The main sources of noise and vibration are drilling and earth-moving equipment and blasting.

Water

Diamond-wire cutting activities, aggregate-washing plants, and dimension stone quarrying activities typically involve significant

use of water resources. Surface water regimes may be altered because of flow diversions, water intake, and changes to the

drainage pattern.

Waste

Rock waste and removed topsoiloverburden are the main inert wastes produced by quarrying activities. Hazardous wastes maybe generated from impurities and trace components included in the exploited (waste) rocks (e.g. asbestos or heavy metals or

minerals that could result in acidic runoff).

Land Conversion

Excavation activities at construction materials extraction sites often involve major topographical and land-cover changes to allow

extraction activities, often including clearing of preexisting vegetation.

Key Actions to Manage Environmental Risk

Air Emissions

Land clearing, location of haul roads, tips and stockpiles, and blasting should take into account weather and location of sensitive

receptors. Dust emissions from drilling, crushing, and grinding should be controlled by dust extractors, collectors, filters, and wet

drilling and processing. Locate the processing plant at the quarry, and use simple materials handling operations. Covered

conveyor belts are preferable to truck transfer. Internal roads should be compacted and water sprays used. Exposed stockpiles

should be covered or planted in grass.



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Reduce noise by using downhole drilling or hydraulic drilling; enclose and clad processing plants, and install sound barriers;

construct berms and plant vegetation for visual and noise screening.

Water

Water needs should be limited through recirculation and reuse. If water use is significant, especially in arid or semi-arid regions,

a water-resource availability and impact assessment should be conducted. Quarrying activities should be designed not to impact

surface or groundwater. Prevent discharge of wastewater with suspended solids by using lined settlement ponds and a

dedicated drainage network.

Waste

Topsoil, overburden, and low-quality materials should be removed, stockpiled near the site, and preserved for rehabilitation.

Hazardous and non- hazardous waste management plans should be developed and adopted during the design and planning

phase. Hazardous waste plans should address potential acid rock drainage, which can occur if minerals containing sulphides or

sulfur are exposed to air and water.

Land ConversionDevelopment of quarry sites should strive to minimize land conversion. This requires assessments up front of the quality and

thickness of the deposit and the development of reclamation plans. Elements that should be included in these plans are

preference for thicker deposits, ongoing reclamation of smaller deposits, avoidance of ecologically valuable areas, and

restoration of the site to its condition prior to excavation.

Occupational Health and Safety

Occupational health and safety hazards occur during the operational phase of construction materials extraction projects and

primarily include the following:

Respiratory hazards Noise

Physical hazards

Respiratory Hazards

Occupational exposure to dust and fine particulates is associated with all phases of quarrying activities (e.g. shoveling, ripping,

drilling, blasting, flame-jet cutting, transport, crushing, grinding, screening, and stockpiling operations). Workers with long-term

exposure to fine particulate dust can develop benign pneumoconiosis, emphysema, bronchitis, and fibrosis. Long-term exposure

to silica dust may cause silicosis

Noise

Workers may be exposed to excessive noise levels during quarrying activities that can lead to hearing impairment.

Physical Hazards

Physical injuries may occur during construction material quarrying operation and maintenance activities (e.g. slips, trips and falls,

falling rocks, impact with moving machinery such as front loaders, drillers, crushers, and belt conveyors). Portable drilling

machines; cutting tools and other machinery can cause injuries. Blasting activities can in accidental explosions and injuries.


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Protective Measures

Respiratory Hazards

Excavators, dumpers, dozers, wagon-drills, and other automated equipment that requires an operator should be equipped with

air conditioned, dustproof, and soundproof cabs; an use of personal breathing protection available on an as needed basis.

Noise

To the extent possible, machinery should be shielded. Personal protective equipment should be provided.

Physical hazards

Employees require ongoing training programs on machinery and explosive use, and appropriate machinery (e.g., no portable

drills) needs to be provided. Implement a consistent blasting schedule with warning procedures and after-blast inspections to

identify unexploded charges.

Initial Due diligence Site Visit

Use the opportunity of visiting the facility to assess environmental, social, health, and safety status. This will involve walking the

site, visiting all of the production areas, and reviewing documents. For complex facilities, technical environmental staff may be

needed.

Develop an understanding of the history of the site, the facility, and the surrounding properties to understand whether there might

be historic contamination, permitting issues, or community issues. Check:

History of the site

Age of the facility

Surrounding properties and the kinds of activities that occur on them

Current status of environmental permits and land use permits, and any restrictions placed on the facility, including environmental

and social impact assessment and reclamation plan

Signs of spills, soil subsidence, or stressed vegetation

Water in pits

Talk to neighbors and request information on the facility

Develop an understanding of the excavation processes, existing pollution controls, and potential for improvement and cost

savings. Check:

Housekeepingis the facility clean, are materials stored, etc. (Housekeeping is often an important indicator of the capacity and

drive for environmental compliance)

Age and type of equipment

Pollution control equipment and the maintenance schedule

Types of waste produced, where and how disposed

Types of liquid effluents, where and how disposed

Develop an understanding of the facilitys health and safety regime. Check:

Availability and use of personnel protective equipment such as goggles, hard hats, safety gloves, and the like.


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Content and frequency of employee health and safety training

History of accidents

Frequency of health and safety audits

Annex A: General Description of Industry ActivitiesConstruction Materials Extraction

Extraction activities for construction materials (e.g. limestone, clay, gypsum, and feldspar) typically involves quarrying and

mining, site transport and storage of raw material, crushing, milling, grinding, and shipping to final users including cement plants,

other manufacturer industries, and the construction industry. In the case of aggregates (e.g. gravel and sand) the extracted

material is commonly divided into size classes, stockpiled, and directly shipped to consumers (e.g. concrete mixing plants).

To minimize transportation cost, exploitation sites of limestone, sand, and gravel are commonly located close to processing

plants and the final markets. Because of their relatively higher value and lower availability, other materials such as feldspar, silica

sands, clay, and gypsum, may be economically extracted at greater distances from their intermediate processing facilities and /or final markets. If an exploitation site is located on or near a riverbank and transportation can be accomplished with barges,

materials can be shipped for a long distance.

Construction activities associated with construction material extraction typically include the removal of topsoil, overburden

ground, trees, and vegetation. Stockpiles of these materials are stored in stable, protected, and monitored areas for use in

reinstatement activities. Other preparatory work leading up to exploitation activities includes design and construction of water

drains and ditches, access and internal roads, benches, and preparations for use of explosives. Upfront planning is undertaken

during this phase to ensure acceptable pit slopes during operational and rehabilitation phases.

Activities characteristic of the operations phase include excavation by means of mechanical methods such as shoveling, ripping,

dredging and / or drilling and blasting, in addition to transport, crushing, grinding, milling, and stockpiling of materials.

Management and monitoring of drilling and blasting, including minimization of impacts caused by dust, noise, vibrations, andflyrocks is necessary during the construction and operation phases. Continued planning and implementation of site rehabilitation

is conducted during operations activities.

Activities associated with site closure and reinstatement / rehabilitation include the demolition of building structures, removal of

aboveground and underground utilities, and ensuring the closure and reinstatement of internal and access roads. Slope

stabilization and recontouring of surface ground are typically undertaken, in addition to topsoil reinstatement, revegetation,

including seeding with commercial seed mixes and / or preferably native species. Opportunities to create ecologically valuable

habitats should be exploited. Restoration of the local hydrological network is necessary. Dredging or excavation below the local

water table should generally be reinstated, including appropriate creation of water ponds.

Dimension Stone Quarrying

Dimension stone extraction involves quarrying using explosives and / or diamond wire cutting, site transport and storage of raw

blocks, sorting, cutting and shipping to consumers for direct use, or cutting and polishing. Most of the issues relevant to the

design, construction, operations, and decommissioning phases of construction materials extraction are applicable to dimension

stone quarrying. Basic operations include quarrying by means of mechanical methods (e.g. wire / diamond cutting and sawing) or

drilling and blasting (e.g. smooth blasting and cushion blasting), block splitting, sorting, block moving by lift rigs, and block

transport.


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Construction Materials Extraction Quarries

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