UK agency and legislative context - Introduction to Environmental Impact Assessment - page 72

• the site area of the scheme is more than 5 ha; or

it would provide a total of more than 10,000 m 2 of new commercial floorspace; or

•

• the development would have significant urbanizing effects in a previously non-

urbanized area (e.g. a new development of more than 1,000 dwellings).

(c) Intermodal transhipment facilities and intermodal terminals. In addition to the physical

scale of the development, particular impacts for consideration are increased traffic, noise,
emissions to air and water. Developments of more than 5 ha are more likely to require
EIA.

(d+f+j) Construction of roads, railways (including elevated and underground) and tramways
(unless included in Schedule 1). For linear transport schemes, the likelihood of significant
effects will generally depend on the estimated emissions, traffic, noise and vibration and
degree of visual intrusion and impact on the surrounding ecology. EIA is more likely to be
required for new development over 2 km in length.

(e) Construction of airfields (projects not included in Schedule 1). The main impacts to be

considered in judging significance are noise, traffic generation and emissions. New
permanent airfields will normally require EIA, as will major works (such as new runways
or terminals with a site area of more than 10 ha) at existing airports. Smaller scale
development at existing airports is unlikely to require EIA unless it would lead to
significant increases in air or road traffic.

(g) Construction of harbours and port installations , including fishing harbours. Primary

impacts for consideration are those on hydrology, ecology, noise and increased traffic.
EIA is more likely to be required if the development is on a major scale (e.g. would cover
a site of more than 10 ha). Smaller developments may also have significant effects where
they include a quay or pier which would extend beyond the high water mark or would
affect wider coastal processes.

(h) Construction of inland waterways, canalization and flood relief works. The likelihood of

significant impacts is likely to depend primarily on the potential wider impacts on the
surrounding hydrology and ecology. EIA is more likely to be required for development of
over 2 km of canal.

The impact of flood relief works is especially dependent upon the nature of the location
and the potential effects on the surrounding ecology and hydrology. Schemes for which
the area of the works would exceed 5 ha or which are more than 2 km in lengtb would
normally require EIA.

(i) Dams and other installations designed to hold water or store it on a long-term basis. In

considering such developments, particular regard should be had to the potential wider
impacts on the hydrology and ecology, as well as to the physical scale of the development.
EIA is likely to be required for any major new dam (e.g. where the construction site
exceeds 20 ha).

(k +1) Installation of oil pipelines, gas pipelines and long-distance aqueducts (including water

and sewerage pipelines). For underground pipelines, the major impact to be considered
will generally be the disruption to the surrounding ecosystems during construction, while
for overground pipelines visual impact will be a key consideration. EIA is more likely to
be required for any pipeline over 6km long. EIA is unlikely to be required for pipelines
laid underneath a road, or for those installed entirely by means of tunnelling.