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TBT-free anti-fouling developments
Volume22/Number9/September 1991 ships pass daily. Mr Mitsatsos outlined that few facilities exist and where they do they are largely unknown due to poor organization and coordination. HELMEPA had developed a strategy after a 16 month study which not only included the beach clean-ups, but a seafarers training programme, to ensure that facilities are not neglected by shipping, and the establishment of a Federation of Marine Protection Associations in the Mediterranean. Other countries may soon be forced to follow their example as the lack of facilities may prevent them being granted special area status by the IMO. LAURENCE WRIGHT
Contamination of Flooded Tin Mine Tin mine water containing significant concentrations of heavy metals is posing a threat to 70 boreholes and private water wells in southwest Britain although the public water supply should remain safe. The National River Authority (NRA) have tested water samples from the flooded abandoned Cornish tin mine, Wheal Jane, and have found it to be acidic and to contain iron, zinc, copper, cadmium, arsenic, aluminium, cobalt nickel, mercury, and selenium. The Wheal Jane mine was opened by Consolidated Goldfields in 1969 and worked by Rio Tinto Zinc between 1978 and 1988. It is now owned by Carnon Consolidated who were forced to close operations as tin price levels have continued to drop and when, in February 1991, the Department of Trade and Industry withdrew its financial support. The cessation of pumping within the mine means that the water level is returning to its natural levels and is already only 40 m from an outflow from which it will join underground water courses. The water is expected to reach this overflow in 4 to 10 weeks time. The NRA is now working with Carnon Consolidated to prevent contamination of local water supplies probably by the reintroduction of pumping operations. Who will pay for this has not yet been made clear. With the drop in tin prices there are now hundreds of flooded abandoned tin mines in Cornwall. The heavy metal contamination in the water should equilibrate with time but careful control will need to be maintained over some of the mines to prevent contamination. PHILIPPA AMBROSE
TBT-free Anti-fouling Developments Increasing pressure from international legislation on TBT (tributyltin) anti-fouling paints has led many manufacturers to desire TBT-free materials. TBT is now well known for its harmful effect on the environment but until recently TBT-free paints have not come up to the required standards for large ships. Manufacturers are now, however, coming up with viable alternatives and such is the faith of BP in a new paint
from Joton's that they have coated their 270 000 t dwt tanker British Resolution in Joton's Seaguardian. Their decision came after increasing legislation banning TBTbased products and the discharge of waste water containing TBT from ships being washed down in dry dock. The anti-fouling had undergone extensive tests on ferries, Royal Naval Ships and cargo vessels and had, only recently, been actively marketed. BP had also tested the product themselves on small areas of its own ships prior to making the decision. The British Resolution's hull was blasted and given a full coat of tar epoxy anticorrosive system before being coated with two layers of Seaguardian. The operation was carried out at Singapore Sembawang yard. As the hull was stripped to bare steel, it will mean that the product has a very fair test as it is not competing with any old paints left on the hull. The product is expected to last for 3 years rather than the usual 5-year life of TBT-based products but BP have decided to pay the price to be environmentally friendly. International (formerly International Paints) have also developed a new TBT-free antifoul coating which incorporates the long polishing and smooth performance of self polishing polymers (SPCs). It is the first TBT-free paint to be developed which is capable of incorporating this efficient smooth coating which reduced hull friction and International will not give away its secret ingredients. A breakthrough in copolymer alloy technology has made active-zone control (AZC) possible and this is the key to self-polishing systems. Normally in a TBT product, the seawater forms a soluble surface with copolymer bound TBT and this is removed by the selfpolishing action of the passing water on the vessel's hull thus exposing fresh antifouling. The new alloy allows this to be achieved without TBT. Three vessels have been coated with it and International are awaiting feedback on its performance although the results so far have been successful enough for the company to launch the marketing of the product. It is expected to have a current lifespan of around 4 years.
Round-the-World News Hong Kong Shipowners are seeking a limit on compensation awards in Hong Kong to prevent the city being used by US pollution victims attempting to gain far higher damages awards than they would receive in their own courts. The US abandoned international oil pollution liability conventions when it passed its Oil Pollution Act in August 1990 and the Hong Kong shipowners want their own courts to limit liability to these original levels. In Hong Kong, ship managers may not have liability in a pollution incident and this, together with liability awards limits, would make it an attractive maritime centre. The request for these limits is being backed by the Marine Department which runs the Hong Kong registry 427
Contamination of Flooded Tin Mine Tin mine water containing significant concentrations of heavy metals is posing a threat to 70 boreholes and private water wells in southwest Britain although the public water supply should remain safe. The National River Authority (NRA) have tested water samples from the flooded abandoned Cornish tin mine, Wheal Jane, and have found it to be acidic and to contain iron, zinc, copper, cadmium, arsenic, aluminium, cobalt nickel, mercury, and selenium. The Wheal Jane mine was opened by Consolidated Goldfields in 1969 and worked by Rio Tinto Zinc between 1978 and 1988. It is now owned by Carnon Consolidated who were forced to close operations as tin price levels have continued to drop and when, in February 1991, the Department of Trade and Industry withdrew its financial support. The cessation of pumping within the mine means that the water level is returning to its natural levels and is already only 40 m from an outflow from which it will join underground water courses. The water is expected to reach this overflow in 4 to 10 weeks time. The NRA is now working with Carnon Consolidated to prevent contamination of local water supplies probably by the reintroduction of pumping operations. Who will pay for this has not yet been made clear. With the drop in tin prices there are now hundreds of flooded abandoned tin mines in Cornwall. The heavy metal contamination in the water should equilibrate with time but careful control will need to be maintained over some of the mines to prevent contamination. PHILIPPA AMBROSE
TBT-free Anti-fouling Developments Increasing pressure from international legislation on TBT (tributyltin) anti-fouling paints has led many manufacturers to desire TBT-free materials. TBT is now well known for its harmful effect on the environment but until recently TBT-free paints have not come up to the required standards for large ships. Manufacturers are now, however, coming up with viable alternatives and such is the faith of BP in a new paint
from Joton's that they have coated their 270 000 t dwt tanker British Resolution in Joton's Seaguardian. Their decision came after increasing legislation banning TBTbased products and the discharge of waste water containing TBT from ships being washed down in dry dock. The anti-fouling had undergone extensive tests on ferries, Royal Naval Ships and cargo vessels and had, only recently, been actively marketed. BP had also tested the product themselves on small areas of its own ships prior to making the decision. The British Resolution's hull was blasted and given a full coat of tar epoxy anticorrosive system before being coated with two layers of Seaguardian. The operation was carried out at Singapore Sembawang yard. As the hull was stripped to bare steel, it will mean that the product has a very fair test as it is not competing with any old paints left on the hull. The product is expected to last for 3 years rather than the usual 5-year life of TBT-based products but BP have decided to pay the price to be environmentally friendly. International (formerly International Paints) have also developed a new TBT-free antifoul coating which incorporates the long polishing and smooth performance of self polishing polymers (SPCs). It is the first TBT-free paint to be developed which is capable of incorporating this efficient smooth coating which reduced hull friction and International will not give away its secret ingredients. A breakthrough in copolymer alloy technology has made active-zone control (AZC) possible and this is the key to self-polishing systems. Normally in a TBT product, the seawater forms a soluble surface with copolymer bound TBT and this is removed by the selfpolishing action of the passing water on the vessel's hull thus exposing fresh antifouling. The new alloy allows this to be achieved without TBT. Three vessels have been coated with it and International are awaiting feedback on its performance although the results so far have been successful enough for the company to launch the marketing of the product. It is expected to have a current lifespan of around 4 years.
Round-the-World News Hong Kong Shipowners are seeking a limit on compensation awards in Hong Kong to prevent the city being used by US pollution victims attempting to gain far higher damages awards than they would receive in their own courts. The US abandoned international oil pollution liability conventions when it passed its Oil Pollution Act in August 1990 and the Hong Kong shipowners want their own courts to limit liability to these original levels. In Hong Kong, ship managers may not have liability in a pollution incident and this, together with liability awards limits, would make it an attractive maritime centre. The request for these limits is being backed by the Marine Department which runs the Hong Kong registry 427