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Sea Empress Environmental Evaluation Committee
Spill Science & Technology Bulletin, Vol. 3, No. 3, pp. 103 106, 1996
Pergamon PII: S1353-2561 (96)00020-5
(~ 1997 SEEEC. Published by Elsevier Science Ltd All rights reserved. Printed in Great Britain 1353 2561/96 $15.00+0.00
Sea Empress Environmental Evaluation Committee Initial Report
July 1996
SEEEC
Sea Empress' Environmental Evaluation Committee, Rivers House, St Mellons Business Park, St Mellons, Cardiff CF3 0LT, UK (Tel." O0 44 1222 770088; Fax: O0 44 1222 798555)
The Sea Empress oil spill off Milford Haven, South West Wales, U K occurred in February 1996. At the start of the incident, swift action was taken by many organisations to assess environmental damage, to clean up the shoreline, to protect sensitive areas and to save as many birds damaged by the oil as possible. This led to the need to establish whether there were gaps in the information being collected or undue replication of effort through lack of co-ordination and to assess the effectiveness of the efforts taken to minimise the damage to amenity and wildlife. It is also very important to identify the lessons to be learned from this unfortunate incident for future oil spills which may occur. For these reasons, the U K Government set up the independent Sea Empress Environmental Evaluation Committee (SEEEC), under the Chairmanship of Professor Ron Edwards, to evaluate the environmental impact of the oil spill and the subsequent clean-up and remedial activities. The SEEEC Initial Report was published in July 1996 and provides a description of the committee's role, the monitoring and other environmental studies undertaken by a wide variety of organisations following the grounding of the tanker, and of the proposals the SEEEC makes for more than 80 additional studies. The funding for these studies will come mainly from government and public bodies, much of which has already been found. The committee intends to publish a final report around the autumn 1997. The following is the Summary of the Initial Report.
The Committee • The committee's terms of reference include coordinating environmental monitoring work, ensuring that a comprehensive set of environmental data is obtained, assessing the overall environmental impact of the incident, and publishing the principal findings with recommendations as appropriate. • SEEEC consists of a main committee and three task groups: Marine, Shoreline and Terrestrial, and Pollutant Behaviour. The task groups include experts from a wide range of organisations including public and voluntary bodies, academic institutions and technical companies working in the region. • The task groups identified studies that were required to fill gaps in the monitoring programme established after the spill. These studies eventually formed the work plan.
The Oil Spill and Response • The Sea Empress released approximately 72 000 t of crude oil and about 360 t of heavy fuel oil in the period 15-21 February 1996 when it grounded off Milford Haven in south-west Wales, and while it was at the jetty. Some further fuel oil leaked out as the tanker was moved out of Milford Haven on the way to Belfast. 103
SEEEC
• South-west Wales has a coastline o f outstanding beauty and scientific interest, well-studied in the past. The area includes around 35 Sites of Special Scientific Interest (SSSIs), a national park, one of the United Kingdom's three Marine Nature Reserves, two potential European Special Areas of Conservation, and other specially designated areas. The region is also important for fishing and tourism. • The coastline within Milford Haven was heavily oiled, and outside the Haven much o f the oil moved south and then eastwards parallel to the south coast of Pembrokeshire, affecting this coastline as far as Pendine Sands in Carmarthen Bay. Some oil reached Skomer Island north west of the Haven, but no oil has been observed north of St David's Head. Lundy Island in the Bristol Channel received light oiling, and some pellets of oil reached the Irish coast; no oiling of the coast of mainland Devon and Cornwall has been reported. • The Sea Empress spill is the third largest tanker spill in U K waters, though volume of oil is not necessarily the best indicator of environmental impact. • Some oil was recovered mechanically at sea, and between 17 and 25 February 445 t of chemical dispersants were used to break up the oil into dispersed droplets in order to reduce the risk to the coastline and to birds at sea. A policy was adopted of not using dispersants within 1 km o f the shoreline so as to avoid shallow water (where the dispersed oil would be less readily diluted, thereby increasing the risk to marine life). • Around 200 km of coastline were affected by the spill, and a major clean-up operation was mounted. Beaches were cleaned mostly using mechanical methods, but with some use of dispersants to remove weathered oil from rocks next to selected beaches where amenity value was judged to take priority. • The main recreational beaches were cleaned by Easter, though some clean-up activity continues. The beaches now attract many visitors. There has been occasional re-oiling--mostly tar balls--on some of the beaches, but these incidents have been dealt with rapidly. • A considerable amount of monitoring and research activity started almost immediately the tanker went aground. • The RSPCA (Royal Society for the Prevention of Cruelty to Animals) set up an emergency facility for live oiled birds. This handled more than 3100 birds, of which around 2500 were common scoter Melanitta nigra. More than 2000 cleaned birds were released. • The incident has had adverse effects on the local fishing and tourism industries. 104
The Effects on Fisheries and the Marine Environment • The two key concerns initially were to establish the size of the area affected by the oil and to determine how badly individual fin fish and shellfish had been contaminated. Research vessels were used to map concentrations of oil in water and sediment, and over 500 samples of fish and shellfish have been analysed for hydrocarbon content. • A fishing exclusion order was applied to the region. This banned the catching o f fish and shellfish--both commercially and for sport--within a designated area. Fin fish, however, were found to have little or no contamination, and the ban on salmon and sea trout was lifted on 3 May, and on other fin fish on 21 May. Shellfish, especially the bivalve molluscs (such as cockles Cerastoderma edule and mussels Mytilus edulis), were more heavily contaminated and have recovered more slowly, though it is likely that the ban on these will be lifted progressively. The ban was lifted for Burry Inlet on 3 July. • As well as studies on commercial species such as salmon Salmo salar and sea trout Salmo trutta, the task group has recommended studies for assessing impact and recovery for a range of key species, particularly those which are important for food chains or in assessing the effect of the spill on SSSIs and Skomer Marine Nature Reserve.
The Effects on Shoreline and Terrestrial Environments • Rocky shores. Heavy limpet Patella spp mortality-generally 5% to 50%, but as much as 90% on one site--has been recorded, and there have been significant effects on periwinkles Littorina spp, barnacles Cirripedia and sea slaters Ligia spp. Pink encrusting coralline algae Lithophyllum incrustans and Phymatolithon purpureum have been extensively bleached in some areas. Fewer than 20 of the previous 150 rare cushion starfish Asterina phylactica remain in West Angle Bay, the area in which they were first identified. • Sediment shores. There have been mass strandings of lower shore bivalves, urchins and starfish, with some species washed up in their hundreds on south Pembrokeshire beaches. • Saltmarshes, shingle, sand dunes and cliff vegetation. Significant patches of vegetation have been oiled, with some damage to the rare narrow-leaved eelgrass Zostera angustifolia and sea purslane Atriplex portulacoides. To avoid further damage, oil has not been cleaned from saltmarshes. Foliage of thrift Armeria maritima and red fescue Festuca rubra has been affected, as have some lichens. Spill Science & Technology Bulletin 3(3)
SEEEC
• Agriculture. Samples of grass, crops and sheep tissue showed that contamination by airborne oil decreased rapidly and had no agricultural food safety implications. • Birds. By 1 June, more than 6900 oiled birds of at least 28 species had been recovered dead or alive. 66% were c o m m o n scoter Melanitta nigra and 28% were guillemots Uria aalge and razorbills Alca torda. The peak period was 24 February to 4 March. Most were found along the south coast o f Pembrokeshire and adjacent Carmarthenshire. • Mammals. Grey seals Halichoerus grypus around Skomer Island have been oiled, but none has been found dead or significantly distressed. Although there have been strandings of seals and cetaceans, none of these has directly been associated with the oil spill. There does not seem to have been any significant effect on the greater horseshoe bats Rhinolophus ferrumequinum in the Castlemartin sea caves. • Recreation and amenity. It is too early for an accurate assessment o f the effect of the spill.
The Fate and Behaviour of the Oil, and the Effectiveness of the Clean-up • A significant percentage of the oil, at least one third, will have evaporated from the sea surface.
Spill Science & Technology Bulletin 3(3)
• Initial estimates suggest that 50% of the spill volume dispersed into the water column as the result of a combination of natural and chemical dispersion. The ultimate fate of this dispersed oil needs to be assessed. • Recent samples show very low levels of total hydrocarbons in water. • The quantity of oil recovered at sea and from beaches is estimated to have been a relatively small percentage of the oil that was spilled. • The amount of oil trapped in inaccessible parts of the coastline and in sand and shingle beaches needs to be estimated. • An independent expert will be appointed to assess the effectiveness of the clean-up operation.
Copies of the SEEEC Initial Report can be obtained from: Dr Tim Kirby Secretary of the Sea Empress Environmental Evaluation Committee Rivers House St Mellons Business Park St Mellons Cardiff CF3 0LT United Kingdom
105
SEEEC
SOUTH WEST WALES
\ i i
Skomer
i
Island
Carmarthen
..
‘.
Bay
..
BRISTOL CHANNEL
I .-
.-
.-
.-
‘-
--
.-
.-
.-
__
__
__. I
Wiseman’s
Bri
SAUNDERSFOO Skokholm
PEMBROKE Freshwater
n
SITE OF SPECIAL SCIENTIFIC
0
MARINE
: _:
NATURE
NATIONAL
INTEREST
RESERVE
NATURE
SPECIAL PROTECTION CANDIDATE
West
RESERVE AREA
SPECIAL AREA
OF CONSERVATION St. Govan’s
Head
Fig. 1
106
Spill Science & Technology Bulletin 3(3)
Pergamon PII: S1353-2561 (96)00020-5
(~ 1997 SEEEC. Published by Elsevier Science Ltd All rights reserved. Printed in Great Britain 1353 2561/96 $15.00+0.00
Sea Empress Environmental Evaluation Committee Initial Report
July 1996
SEEEC
Sea Empress' Environmental Evaluation Committee, Rivers House, St Mellons Business Park, St Mellons, Cardiff CF3 0LT, UK (Tel." O0 44 1222 770088; Fax: O0 44 1222 798555)
The Sea Empress oil spill off Milford Haven, South West Wales, U K occurred in February 1996. At the start of the incident, swift action was taken by many organisations to assess environmental damage, to clean up the shoreline, to protect sensitive areas and to save as many birds damaged by the oil as possible. This led to the need to establish whether there were gaps in the information being collected or undue replication of effort through lack of co-ordination and to assess the effectiveness of the efforts taken to minimise the damage to amenity and wildlife. It is also very important to identify the lessons to be learned from this unfortunate incident for future oil spills which may occur. For these reasons, the U K Government set up the independent Sea Empress Environmental Evaluation Committee (SEEEC), under the Chairmanship of Professor Ron Edwards, to evaluate the environmental impact of the oil spill and the subsequent clean-up and remedial activities. The SEEEC Initial Report was published in July 1996 and provides a description of the committee's role, the monitoring and other environmental studies undertaken by a wide variety of organisations following the grounding of the tanker, and of the proposals the SEEEC makes for more than 80 additional studies. The funding for these studies will come mainly from government and public bodies, much of which has already been found. The committee intends to publish a final report around the autumn 1997. The following is the Summary of the Initial Report.
The Committee • The committee's terms of reference include coordinating environmental monitoring work, ensuring that a comprehensive set of environmental data is obtained, assessing the overall environmental impact of the incident, and publishing the principal findings with recommendations as appropriate. • SEEEC consists of a main committee and three task groups: Marine, Shoreline and Terrestrial, and Pollutant Behaviour. The task groups include experts from a wide range of organisations including public and voluntary bodies, academic institutions and technical companies working in the region. • The task groups identified studies that were required to fill gaps in the monitoring programme established after the spill. These studies eventually formed the work plan.
The Oil Spill and Response • The Sea Empress released approximately 72 000 t of crude oil and about 360 t of heavy fuel oil in the period 15-21 February 1996 when it grounded off Milford Haven in south-west Wales, and while it was at the jetty. Some further fuel oil leaked out as the tanker was moved out of Milford Haven on the way to Belfast. 103
SEEEC
• South-west Wales has a coastline o f outstanding beauty and scientific interest, well-studied in the past. The area includes around 35 Sites of Special Scientific Interest (SSSIs), a national park, one of the United Kingdom's three Marine Nature Reserves, two potential European Special Areas of Conservation, and other specially designated areas. The region is also important for fishing and tourism. • The coastline within Milford Haven was heavily oiled, and outside the Haven much o f the oil moved south and then eastwards parallel to the south coast of Pembrokeshire, affecting this coastline as far as Pendine Sands in Carmarthen Bay. Some oil reached Skomer Island north west of the Haven, but no oil has been observed north of St David's Head. Lundy Island in the Bristol Channel received light oiling, and some pellets of oil reached the Irish coast; no oiling of the coast of mainland Devon and Cornwall has been reported. • The Sea Empress spill is the third largest tanker spill in U K waters, though volume of oil is not necessarily the best indicator of environmental impact. • Some oil was recovered mechanically at sea, and between 17 and 25 February 445 t of chemical dispersants were used to break up the oil into dispersed droplets in order to reduce the risk to the coastline and to birds at sea. A policy was adopted of not using dispersants within 1 km o f the shoreline so as to avoid shallow water (where the dispersed oil would be less readily diluted, thereby increasing the risk to marine life). • Around 200 km of coastline were affected by the spill, and a major clean-up operation was mounted. Beaches were cleaned mostly using mechanical methods, but with some use of dispersants to remove weathered oil from rocks next to selected beaches where amenity value was judged to take priority. • The main recreational beaches were cleaned by Easter, though some clean-up activity continues. The beaches now attract many visitors. There has been occasional re-oiling--mostly tar balls--on some of the beaches, but these incidents have been dealt with rapidly. • A considerable amount of monitoring and research activity started almost immediately the tanker went aground. • The RSPCA (Royal Society for the Prevention of Cruelty to Animals) set up an emergency facility for live oiled birds. This handled more than 3100 birds, of which around 2500 were common scoter Melanitta nigra. More than 2000 cleaned birds were released. • The incident has had adverse effects on the local fishing and tourism industries. 104
The Effects on Fisheries and the Marine Environment • The two key concerns initially were to establish the size of the area affected by the oil and to determine how badly individual fin fish and shellfish had been contaminated. Research vessels were used to map concentrations of oil in water and sediment, and over 500 samples of fish and shellfish have been analysed for hydrocarbon content. • A fishing exclusion order was applied to the region. This banned the catching o f fish and shellfish--both commercially and for sport--within a designated area. Fin fish, however, were found to have little or no contamination, and the ban on salmon and sea trout was lifted on 3 May, and on other fin fish on 21 May. Shellfish, especially the bivalve molluscs (such as cockles Cerastoderma edule and mussels Mytilus edulis), were more heavily contaminated and have recovered more slowly, though it is likely that the ban on these will be lifted progressively. The ban was lifted for Burry Inlet on 3 July. • As well as studies on commercial species such as salmon Salmo salar and sea trout Salmo trutta, the task group has recommended studies for assessing impact and recovery for a range of key species, particularly those which are important for food chains or in assessing the effect of the spill on SSSIs and Skomer Marine Nature Reserve.
The Effects on Shoreline and Terrestrial Environments • Rocky shores. Heavy limpet Patella spp mortality-generally 5% to 50%, but as much as 90% on one site--has been recorded, and there have been significant effects on periwinkles Littorina spp, barnacles Cirripedia and sea slaters Ligia spp. Pink encrusting coralline algae Lithophyllum incrustans and Phymatolithon purpureum have been extensively bleached in some areas. Fewer than 20 of the previous 150 rare cushion starfish Asterina phylactica remain in West Angle Bay, the area in which they were first identified. • Sediment shores. There have been mass strandings of lower shore bivalves, urchins and starfish, with some species washed up in their hundreds on south Pembrokeshire beaches. • Saltmarshes, shingle, sand dunes and cliff vegetation. Significant patches of vegetation have been oiled, with some damage to the rare narrow-leaved eelgrass Zostera angustifolia and sea purslane Atriplex portulacoides. To avoid further damage, oil has not been cleaned from saltmarshes. Foliage of thrift Armeria maritima and red fescue Festuca rubra has been affected, as have some lichens. Spill Science & Technology Bulletin 3(3)
SEEEC
• Agriculture. Samples of grass, crops and sheep tissue showed that contamination by airborne oil decreased rapidly and had no agricultural food safety implications. • Birds. By 1 June, more than 6900 oiled birds of at least 28 species had been recovered dead or alive. 66% were c o m m o n scoter Melanitta nigra and 28% were guillemots Uria aalge and razorbills Alca torda. The peak period was 24 February to 4 March. Most were found along the south coast o f Pembrokeshire and adjacent Carmarthenshire. • Mammals. Grey seals Halichoerus grypus around Skomer Island have been oiled, but none has been found dead or significantly distressed. Although there have been strandings of seals and cetaceans, none of these has directly been associated with the oil spill. There does not seem to have been any significant effect on the greater horseshoe bats Rhinolophus ferrumequinum in the Castlemartin sea caves. • Recreation and amenity. It is too early for an accurate assessment o f the effect of the spill.
The Fate and Behaviour of the Oil, and the Effectiveness of the Clean-up • A significant percentage of the oil, at least one third, will have evaporated from the sea surface.
Spill Science & Technology Bulletin 3(3)
• Initial estimates suggest that 50% of the spill volume dispersed into the water column as the result of a combination of natural and chemical dispersion. The ultimate fate of this dispersed oil needs to be assessed. • Recent samples show very low levels of total hydrocarbons in water. • The quantity of oil recovered at sea and from beaches is estimated to have been a relatively small percentage of the oil that was spilled. • The amount of oil trapped in inaccessible parts of the coastline and in sand and shingle beaches needs to be estimated. • An independent expert will be appointed to assess the effectiveness of the clean-up operation.
Copies of the SEEEC Initial Report can be obtained from: Dr Tim Kirby Secretary of the Sea Empress Environmental Evaluation Committee Rivers House St Mellons Business Park St Mellons Cardiff CF3 0LT United Kingdom
105
SEEEC
SOUTH WEST WALES
\ i i
Skomer
i
Island
Carmarthen
..
‘.
Bay
..
BRISTOL CHANNEL
I .-
.-
.-
.-
‘-
--
.-
.-
.-
__
__
__. I
Wiseman’s
Bri
SAUNDERSFOO Skokholm
PEMBROKE Freshwater
n
SITE OF SPECIAL SCIENTIFIC
0
MARINE
: _:
NATURE
NATIONAL
INTEREST
RESERVE
NATURE
SPECIAL PROTECTION CANDIDATE
West
RESERVE AREA
SPECIAL AREA
OF CONSERVATION St. Govan’s
Head
Fig. 1
106
Spill Science & Technology Bulletin 3(3)