The value of such resources to society as a whole must, therefore, be weighed against the positive benefits of job creation and the site should be rejected if there are particular impacts for instance to endangered species.
3.2.3. Existence of adverse natural conditions
A number of adverse natural conditions will need to be examined, such as slope of the land, unstable soil and subsurface conditions, land prone to landslide activity and land prone to volcanic or seismic activity. Availability of water supply is considered separately. The main considerations for industrial sites in relation to natural conditions is to avoid:
poorly drained low lying land and particularly land in flood plains which are liable to
coastal zones liable to inundation from tidal and storm activity,
Industrial estates are attracted to large areas of flat land and such land is often most available in flood plain and coastal locations. Care must therefore be taken to assess the likely impacts of regional flooding and the incidence of coastal inundation. The impact of the surface water drainage from the site on the existing drainage pattern must also be considered.
At site selection level, the aim should, therefore, be to avoid project locations subject to severe natural constraints and particularly land subject to:
flooding - particularly flood plains,
Where mitigation is viable then measures will be required at both the site and infrastructure level and at estate design level. Adverse conditions such as low lying land can increase the costs of water supply and waste disposal services. Pumping stations may be required for water-supply and sewerage systems to be effective.
These design measures are relevant to the layout and design phase of the project; but the costs associated with such mitigation measures must also be factored into the overall project costs to determine the viability of individual sites and allow the realistic consideration of alternative sites.
Impact on adjoining land users
The assessment of environmental impacts on land uses immediately adjoining the proposed site will be important in assessing the relative merits of alternative sites. There may be high population concentrations in the immediate area or there may be agricultural production or other resources which could be affected by heightened levels of pollution. The quantification of environmental impact should be incorporated in the alternative site assessments. This should be done in terms of any health impacts and any human welfare impacts (e.g. loss of income from reduced crop yields) which will result from increased levels of pollution. The reduction in adjoining land and property values that may result from the placing industrial users next to other users, and particularly the affect on residential land values in the area, should be assessed.
Existing background levels of pollution in the area may already be high and the advisability of adding new potential sources in such a situation may be unacceptable. Background levels of air, water and noise pollution resulting from adjoining land users should all be measured to allow assessment of cumulative impacts.
Local micro-climatic conditions can result in temperature inversion. Such climatic conditions can exacerbate atmospheric pollution, and lead to the formation of photochemical smog. The likely effects of air pollution on local communities should be assessed.
If health and human welfare impacts are great, proper quantification and costing of impacts can make certain sites totally unacceptable e.g. those close to high population