To combat or stop oil leakages from sources on the ocean floor is far too complex to be covered by this presentation. However there are examples of very successful operations where wrecks have been emptied of oil. Reports from such operations are available.
D. Clean-up Equipment Employed by Oil Spill Response Bodies, Specifications and Reasons for Choice
When exploration for oil started on the Norwegian Continental Shelf, followed by production in the late 70s/early 80s, the authorities introduced their requirements for contingency against oil spills. The requirements are mentioned earlier in this presentation. The authorities further directed the oil industry to document that they were able to meet the issued requirements. To enable the industry to achieve this the Pollution Control Authorities in Norway granted spill permits for the purpose of testing- and development of oil recovery equipment. It soon became obvious that there was no equipment available on the market which was suitable for the conditions in the North- and Barents Sea and which could satisfy the standards set by the government.
A development- and test program was started. Tests/exercises, where oil was released, were arranged offshore once or twice a year. Both independent contractors and the pollution control authorities monitored the release and recovery of the test oil. In 1987/-88 the Transrec unit had been developed and the industry could document a recovery rate of 300 m3/hour under favourable conditions. Even though the offshore tests had proven the recovery rate to fall sharply with worsening weather conditions they showed that the requirement of 8,000m3/day in significant wave height up 2.5 m had been met.
Brief Description of Transrec
The Transrec system is electro-hydraulically operated and driven by the OR vessels' hydraulic power unit. Transrec consists mainly of the following parts:
・ Lower baseplate with towing attachment and hydraulically operated wheels that can be lowered for low-speed transportation over short distances.
・ Upper, revolving baseplate with drum and control panel.
・ Floating hose with f 150 mm transfer hose and hydraulic hoses and electrical cables for the control and operation of the skimmer functions.
・ Skimmer head with pump.
・ Emulsion-breaker system for continuous injection of oil/water emulsion-breaking chemicals during the recovery process.
・ The Transrec system can be operated from the control panel or by remote control by radio from the bridge.
・ A tension system that automatically pays out or reels in the hose during a transfer operation if the distance between the vessels increases or decreases.
Framo NOFO Transrec systems are designed to operate in seas with waves with a significant height of up to 4.0 m, and have a maximum capacity of 300 m3per hour against a 55 m water column and viscosity of 1,500 cSt.
The system can be operated by I person. When installed, the Transrec system serves 2 purposes:
1. Recovery of oil from the boom systems.
2. Transfer of recovered oil to another vessel or to a tank onshore.
Parallel with and after the development of the Transrec unit, a boom suitable for offshore conditions was developed/selected. After numerous tests, an existing boom which was modified to meet NOFOs requirements was selected. The main characteristics of this boom is a depth of 1.5 m and a flotation chamber which has a diameter of 1.3 m. Each length of boom is 400 m.
Requests/Orders for Operations
Any member of NOFO has the right to activate the whole organisation in an emergency. As part of the contingency organisation, NOFO has an alarm centre where qualified personnel are on duty at all times. NOFO's resources may be activated by telephone, provided the operations order is confirmed as soon as possible in writing.
Chain of Commands
According to Norwegian law the responsibility to take action when an oil spill has occurred lies with the polluter.
