Pre-operational Stage

The main steps in identifying and evaluating a potential mineral working site and securing the necessary permissions are:

Exploration
Securing mineral working rights
Establishing whether the site is suitable for extraction
Planning of possible extraction
Applying for planning consent and environmental permits

Exploration

Photograph 1. Test drilling rig Because the geology of England is fairly well known, target areas for possible mineral working can be readily identified. The priority for investigation is normally given to sites or areas where permission for extraction is more likely to be secured because these have previously been identified by mineral planning authorities as being generally suitable for properly controlled mineral working.

Mineral deposits are investigated using:

invasive techniques such as digging of trial pits and drilling and recovering samples for testing; and
non-invasive techniques using geophysics

Most exploration for aggregates is short term with minimal impacts and is therefore regarded by the regulatory authorities as permitted development that can proceed after notifying the minerals planning authority. But there are exceptions where deeper drilling of rock deposits near environmental sensitive locations is required that require separate planning permission.

Samples are tested to determine whether they have the right physical and chemical characteristics to perform well as aggregates and to establish the types and amount of processing that would be required.

Securing mineral working rights

Mineral operators must secure access to land for mineral working by either buying it or leasing the mineral rights. This usually happens only of the landowner is willing to sell or enter into an arrangement although a legal provision under the Mine Working Facilities Support Act does allow for compulsory purchase in certain limited circumstances in the National interest. Some sites that might be suitable for mineral extraction in social, economic and environmental terms remain unavailable because landowners do not wish to sell or lease rights therefore operators may sometimes have to consider alternative sites that are less ideal.

Establishing whether a site is suitable for extraction

When a deposit has been adequately investigated the thickness, lateral extent, volume, tonnage and quality of mineral is known. This provides a basis for estimating the costs of working, processing, transport and market value of the products establishing whether the operation would be economically viable. However that does not mean that permission for extraction would be given. The site must also be suitable in environmental and social terms. Therefore potential impacts are, in most cases, investigated in a process known as environmental impact assessment. This considers matters such as:

nuisance from dust, noise, vibration, and traffic
discharges to surface water
changes to flow and quality of underground water
visual intrusion
impacts on habitats, biodiversity and protected species
impacts on the cultural heritage (e.g. ancient monuments and archaeological sites)
potential instability of the ground
loss of public access to land and footpaths

The necessary information is secured by compiling existing material on the site and its vicinity and undertaking site surveys (e.g. of ecology, archaeology, water quantity and quality, climate etc) some of which require monitoring over a suitable period of time (e.g. seasonal variations in groundwater, use by nesting birds etc). The information is compiled and analysed to identify potential significant environmental impacts and to propose ways in which these can be overcome or minimised. Much of the work is usually done under contract by experienced independent consultancies and experts.

Planning of possible extraction

Planning of possible extraction includes assessment of:

stripping, handling and storage of soil and geological materials resting above the useable mineral
methods, depths and directions of extraction of mineral
water management e.g. pumping and discharges
haulage and handling of materials within the site
methods of processing and location of plant
reduction of emissions and other impacts
access for transport
suitable haulage routes
options for decommissioning and rehabilitating the site.

Applying for planning consent and environmental permits

The prospective operator must apply to the relevant Mineral Planning Authority for planning permission and to the Environment Agency for permits covering discharges to air and water and handling of mining waste. Commonly, the application for environmental licensing is made after planning consent has been given, because both steps are costly. But both types of consent must be in place before any operation can commence. Each planning permission and environmental permit is accompanied by legally enforceable conditions that must be observed during operations at the site. Environmental licence conditions take precedence over planning conditions although planning conditions may sometimes be more stringent than environmental licence conditions.

When all of the consents are in place, operations can commence at the site.