274
A. NELSON-SMITH
spilt in calm conditions. Castellanos (1968) advocated the use of
paraffin waxes or waste wax residues, sprayed at a temperature of
70°C. The addition of 15-20% wax will solidify crudes, although as
much as 50-60% is needed for thinner oils. Similarly, spraying the
slick with polyvinyl plastic in a volatile solvent covers the oil with a
web of fine fibres; the necessary 15% ratio of plastic to oil is expensive,
but the cost can be reduced by incorporating cheaper material such as
waste textile fibre into the oil befors spraying it (Department of
Scientific and Industrial Research, 1963b). During experimental use
of this “ plastic moss ” in France, much of the spray blew away.
Agglomeration was very efficient but difficulty was experienced in
collecting the resultant raft (Rocquement, 1968). Such methods seem
better suited to use on inland or drinking waters than at sea. Mechanical collection a t sea has been discussed in an earlier section (p. 227),
but it should be mentioned that the French collected an appreciable
amount of “ Torrey Canyon ” ‘‘ mousse ” by aligning a coastal tanker
(the ‘‘ Petrobourg ”) at the downwind end of a V-boom. The emulsion
accumulated in a layer about 2 f t (60 cm) thick along the ship’s side
and was pumped aboard from a floating weir device (Holdsworth, 1968,
and Spooner in the following discussion). A similar method of collection
was tried in the Santa Barbara Channel early in 1969.
C. Problem8 in cleansing shores
One of the main lessons of the “ Torrey Canyon ” disaster is the
value of advance planning. Although British government laboratories
had been investigating methods of dealing with coastal oil spills for
years before this (Department of Scientific and Industrial Research,
1961, 1963a; Zuckerman, 1968) the necessity of cleaning so much oil
from so many miles of coast had never previously arisen. In retrospect, it can be seen that some inaccessible coves need never have been
treated. On most shores, far less of the solvent-emulsifiers could have
been used and on others, mechanical methods would have been more
effective. Since that event, local authorities throughout, Britain have
been instructed to prepare oil-pollution plans (Beaumont, 1968 ;
Ministry of Housing and Local Government, 1968). That other governments have need of similar contingency plans is revealed, for example,
by statements of U.S. Senator Muskie (1968) on the “ Ocean Eagle ”
spill in Puerto Rico. Rocquement (1968) has referred to the French
“ Plan Offset ”. British coastal laboratories and marine stations have
been selected to act as emergency scientific or technical bases and maps
have been drawn up defining those sections of coast which are of
special value to biologists, fishermen or holidaymakers (Natural
A. NELSON-SMITH
spilt in calm conditions. Castellanos (1968) advocated the use of
paraffin waxes or waste wax residues, sprayed at a temperature of
70°C. The addition of 15-20% wax will solidify crudes, although as
much as 50-60% is needed for thinner oils. Similarly, spraying the
slick with polyvinyl plastic in a volatile solvent covers the oil with a
web of fine fibres; the necessary 15% ratio of plastic to oil is expensive,
but the cost can be reduced by incorporating cheaper material such as
waste textile fibre into the oil befors spraying it (Department of
Scientific and Industrial Research, 1963b). During experimental use
of this “ plastic moss ” in France, much of the spray blew away.
Agglomeration was very efficient but difficulty was experienced in
collecting the resultant raft (Rocquement, 1968). Such methods seem
better suited to use on inland or drinking waters than at sea. Mechanical collection a t sea has been discussed in an earlier section (p. 227),
but it should be mentioned that the French collected an appreciable
amount of “ Torrey Canyon ” ‘‘ mousse ” by aligning a coastal tanker
(the ‘‘ Petrobourg ”) at the downwind end of a V-boom. The emulsion
accumulated in a layer about 2 f t (60 cm) thick along the ship’s side
and was pumped aboard from a floating weir device (Holdsworth, 1968,
and Spooner in the following discussion). A similar method of collection
was tried in the Santa Barbara Channel early in 1969.
C. Problem8 in cleansing shores
One of the main lessons of the “ Torrey Canyon ” disaster is the
value of advance planning. Although British government laboratories
had been investigating methods of dealing with coastal oil spills for
years before this (Department of Scientific and Industrial Research,
1961, 1963a; Zuckerman, 1968) the necessity of cleaning so much oil
from so many miles of coast had never previously arisen. In retrospect, it can be seen that some inaccessible coves need never have been
treated. On most shores, far less of the solvent-emulsifiers could have
been used and on others, mechanical methods would have been more
effective. Since that event, local authorities throughout, Britain have
been instructed to prepare oil-pollution plans (Beaumont, 1968 ;
Ministry of Housing and Local Government, 1968). That other governments have need of similar contingency plans is revealed, for example,
by statements of U.S. Senator Muskie (1968) on the “ Ocean Eagle ”
spill in Puerto Rico. Rocquement (1968) has referred to the French
“ Plan Offset ”. British coastal laboratories and marine stations have
been selected to act as emergency scientific or technical bases and maps
have been drawn up defining those sections of coast which are of
special value to biologists, fishermen or holidaymakers (Natural