THE PROBLEM OF OIL POLLUTION OF THE SEA
23 1
p.p.m. I n Milford Haven, the limit is 50 p.p.m. and, by adopting aircooling instead of the more normal water-cooling of plant, effluent
flows are relatively small. However, there is still an appreciable effect
on the vegetation and sedentary animal life of the shore in the vicinity
of one refinery outfall (G. B. Crapp, personal communication, 1969).
At Fawley in Southampton Water, the oil concentration in a refinery
effluent is as low as 10-20p.p.m. but the rate of discharge is over
100 000 gal (455 000 litres) per minute, so at least 1 500 gal (6 825 litres)
of oil are discharged daily. The result is that in the area of saltmarsh
surrounding the outfall, all vegetation is dead and even normal bacterial
decomposition of the remains appears to have been arrested (Baker,
1969). As a result, erosion of the mud-flats is taking place. Petrochemical works are often sited within or adjoining refineries and, as
far as oil is concerned, the sources and control of pollution are much the
same. The range of products is much wider, so the variety of compounds which might occur in waste waters is enormous ; their origins,
removal from effluents and effects in receiving waters have been considered by Huntress (1953), Montes et al. (1956) and Gloyna and
Malina (1 963).
Oil wells, loading and unloading terminals, refineries and bulk users
of oil are often interconnected by pipeline. Nation-wide or international systems have been used in North America and the Near East
for many years and are now being extended throughout Europe. In
many instances they connect with marine installations or cross waterways near the coast. The volumes and distances involved render a
large pipeline an important potential source of pollution. One of the
largest, the 30 inch (760 mm) Trans Arabia pipeline, carried an average
of 10 million gal (nearly 50 million litres) per day in the early 1960s
but is potentially capable of twice that performance. The 18 inch
(460mm) pipe from Angle Bay (Milford Haven) to Swansea carries
250 000 gal (about one million litres) per hour at an initial pressure of
800 p.s.i. (56 atmos) (OECD, 1961 ; B.P. Llandarcy, personal communication, 1969). Standards for construction and operation have been laid
down by the Institute of Petroleum (1964, 1967) and their significance
to possible pollution is discussed by Henderson (1967). The Ohio River
Valley Water Sanitation Commission (ORSANCO) guidebook (1950)
and Meyer (1967) consider the causes, detection and control of pollution
from pipelines. Leak-detection techniques have an accuracy of 0.03%
of the flow ; in the example given by Meyer, a 30 gal (140 litre)/h leak
in the 100000gal (450 000litre)/h flow of a 12 inch (300mm) pipe
would be detectable by discrepancy after 24 h pumping or by pressuredrop within 2 h of shutdown. Even such a small leak should be located
23 1
p.p.m. I n Milford Haven, the limit is 50 p.p.m. and, by adopting aircooling instead of the more normal water-cooling of plant, effluent
flows are relatively small. However, there is still an appreciable effect
on the vegetation and sedentary animal life of the shore in the vicinity
of one refinery outfall (G. B. Crapp, personal communication, 1969).
At Fawley in Southampton Water, the oil concentration in a refinery
effluent is as low as 10-20p.p.m. but the rate of discharge is over
100 000 gal (455 000 litres) per minute, so at least 1 500 gal (6 825 litres)
of oil are discharged daily. The result is that in the area of saltmarsh
surrounding the outfall, all vegetation is dead and even normal bacterial
decomposition of the remains appears to have been arrested (Baker,
1969). As a result, erosion of the mud-flats is taking place. Petrochemical works are often sited within or adjoining refineries and, as
far as oil is concerned, the sources and control of pollution are much the
same. The range of products is much wider, so the variety of compounds which might occur in waste waters is enormous ; their origins,
removal from effluents and effects in receiving waters have been considered by Huntress (1953), Montes et al. (1956) and Gloyna and
Malina (1 963).
Oil wells, loading and unloading terminals, refineries and bulk users
of oil are often interconnected by pipeline. Nation-wide or international systems have been used in North America and the Near East
for many years and are now being extended throughout Europe. In
many instances they connect with marine installations or cross waterways near the coast. The volumes and distances involved render a
large pipeline an important potential source of pollution. One of the
largest, the 30 inch (760 mm) Trans Arabia pipeline, carried an average
of 10 million gal (nearly 50 million litres) per day in the early 1960s
but is potentially capable of twice that performance. The 18 inch
(460mm) pipe from Angle Bay (Milford Haven) to Swansea carries
250 000 gal (about one million litres) per hour at an initial pressure of
800 p.s.i. (56 atmos) (OECD, 1961 ; B.P. Llandarcy, personal communication, 1969). Standards for construction and operation have been laid
down by the Institute of Petroleum (1964, 1967) and their significance
to possible pollution is discussed by Henderson (1967). The Ohio River
Valley Water Sanitation Commission (ORSANCO) guidebook (1950)
and Meyer (1967) consider the causes, detection and control of pollution
from pipelines. Leak-detection techniques have an accuracy of 0.03%
of the flow ; in the example given by Meyer, a 30 gal (140 litre)/h leak
in the 100000gal (450 000litre)/h flow of a 12 inch (300mm) pipe
would be detectable by discrepancy after 24 h pumping or by pressuredrop within 2 h of shutdown. Even such a small leak should be located