BALTIC SEAENVIRONMENT PROCEEDINGS No. 59 - Helcom

tanks are loosing oil or further damage with outflow can be anticipated
lightering operations preferably in co-operation with tug-boat assistance
(grounding) should be imnediately initiated. The lightering operation must
include also endangered neighbouring tanks.
2.1 The Operational Control Authority (OCA) must denominate a well trained and
experienced expert, to coordinate its decisions at sea (On-scene-coordinator
OSC).
Lightering capacity and tug-boat assistance must be ensured in close cooperation
with tank ship owners association and salvage companies. Agreements
with annexed models of charter contracts must be settled prior to
eventual incidents in order to avoid wasting of valuable time when negotiating
the terms and conditions of the contract(s).
2.2 The OCA with its overall responsibility for oil spill control needs a
comunication centre with telephone, telefax, telex and radio comnunicattions
in order to maintain a permanent link to the OSC and preferably also
to the surveillance plane or surveillance helicopter, and to a patrol ship
which also should be used for other logistic support.
2.3 Pollution response at sea should always have priority in order to avoid
beaching of the slick(s) or shoreline pollution.
2.4 Helcom-recommendation 11/13 on "Development of National Ability to Respond
to Spillages of Oil and Other Harmful Substances" in connection with the
provisional guidelines on its application forms the basis for the national
preparedness with adaequate reaction at sea, details are annexed to this
document, see annex 2.
2.5 If a spill ats sea has occured one has to avoid further spreading with retention
booms to be deployed by tugs or auxiliary vessles; current or tug
speed should not exceed 0,7 kts (0,35 m/s) otherwise the oil would escape
beneath the skirt. Loss of retained oil can also be induced by turbulences
along a boom.
Booms can be used as containment and deflection booms. The rapid spread of
oil at sea over a large area poses the most serious problem in attempting to
tow booms to contain floating oil.
In an effort to prevent spreading and maximise encounter rate, long booms of
300 m or even more in U-, V- or J-configuration may be towed using two
vessels. The collection device is either towed with the boom array or preferably
deployed from a third vessel behind the boom with an opened apex at
the center of the U-Formation. Skimner vessels with integrated skimmer devices
like twin hull vessels, skimning catamarans using weir separation,
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