Noise
Introduction
Sound can simply be considered as any variation in air pressure that is detected by the human ear. The simplest definition of noise is "unwanted sound".
Noise is an inevitable consequence of the working of minerals and is an important health and safety consideration for those working on the site. Whether it becomes "environmental noise" depends on whether it disrupts or disturbs people outside the site boundary.
The extraction process for any material will contain a number of potential noise generating processes. In most cases, there will be a need to remove soil and overburden to expose the mineral. The mineral is then excavated (possibly after having been blasted) and transported from the quarry face to a processing area. The mineral will then be transported from the quarry site for further processing or direct use. These activities usually involve the use of high powered, heavy machinery for excavation and transport of materials within the site. Processing plants will usually include crushing and screening equipment, which will have the inherent noise of the machine, combined with the noise of the material passing through it.
One feature of the activities at mines and quarries is that much of the activity is carried out in the open (Photograph 1). This has implications for the amount of noise attenuation that is possible, as discussed in the following sections.
Photograph 1. Open aspect of quarry and processing plant
Noise is generally one of the main concerns addressed in the planning application for a new or extended mine or quarry. Issues associated with the reaction of a community will include the site location, the existing ambient noise levels, the duration of the operation and hours of work, the characteristics of the noise emitted and the attitude to the operator. As with all environmental issues, the local residents will tend to be more accepting if they believe the operator is sympathetic to their concerns, and doing everything possible to minimise the impact.
As part of the application process, operators will be required to provide information on existing ambient noise levels, predicted noise levels at different stages of the working of the mine or quarry, and details of noise mitigation measures.
In England, government guidance is now contained within Mineral Policy Statement 2: Annex 2 – Noise L0180, which has replaced MPG 11 L0178. In Wales, the Minerals Technical Advice Note (Wales) 1: Aggregates L0214 briefly covers all aspects of the environment, including noise, and is very slightly different to MPS2 as will be shown later. PAN50 Annex A L0294 is the document which should be referred to in Scotland to assess whether noise levels from a proposed mine or quarry are acceptable.
BS 5228-1:2009 445 gives guidance on the control of noise from open sites, and has a specific section relating to quarries. It also has a good summary (in Annex A) of the legislative background for the control of noise, which is not considered in detail here.
This section was originally written in 2004, but has been reviewed and updated using information gathered for the thematic review of ALSF projects, published in 2008 (Reducing the Environmental Effect of Aggregate Quarrying: Dust, Noise and Vibration L0089). The move to Mineral Policy Statement 2 and the update of the British Standards relating to noise at open sites have also been incorporated.
Continued with Units of Measurement TOP Return to Introduction