At-sea oil spill response options. Oil spill response options for use at sea Monitor and EvaluateMonitor and Evaluate Contain and recover at seaContain.

At-sea At-sea oil spill response optionsoil spill response options

Oil spill response options for use Oil spill response options for use at seaat sea

• Monitor and EvaluateMonitor and Evaluate

• Contain and recover at seaContain and recover at sea– Booms and skimmersBooms and skimmers

• Use oil spill dispersantsUse oil spill dispersants

Monitor and EvaluateMonitor and Evaluate

• Use surveillance aircraft to monitor oil slick Use surveillance aircraft to monitor oil slick movementmovement

• Aircraft are equipped with:Aircraft are equipped with:– Cameras and videoCameras and video– SLAR (Side looking Airborne Radar) 20 km SLAR (Side looking Airborne Radar) 20 km

range either side of track range either side of track – Infra-RedInfra-Red– Ultra-VioletUltra-Violet

Surveillance aircraftSurveillance aircraft

Monitor and EvaluateMonitor and Evaluate

• If oil is moving away from the shore there If oil is moving away from the shore there may be no need to respondmay be no need to respond– Small oil slicks are eventually broken up by Small oil slicks are eventually broken up by

the effects of wind and currentsthe effects of wind and currents

• Aerial surveillance is used to find oil slicks Aerial surveillance is used to find oil slicks or illegal oil discharges from shipsor illegal oil discharges from ships

Contain and recover at seaContain and recover at sea

• Booms can be used to contain oil around Booms can be used to contain oil around sourcesource

• Booms can be towed by ships in various Booms can be towed by ships in various configurations to concentrate the spilled oil configurations to concentrate the spilled oil into smaller areainto smaller area

• Skimmers can then be used to collect the Skimmers can then be used to collect the oiloil

Various boom configurationsVarious boom configurations

““J-boom” configurationJ-boom” configuration

““U-boom” configurationU-boom” configuration

Difficulties with booming at seaDifficulties with booming at sea

• Getting to the site of the spill quicklyGetting to the site of the spill quickly– Ships are relatively slowShips are relatively slow

• Wave and weather constraintsWave and weather constraints– Booming is not possible in rough seasBooming is not possible in rough seas

• Laws of hydrodynamicsLaws of hydrodynamics– Booms towed faster than approximately Booms towed faster than approximately

0.7 knots will allow oil to pass under them0.7 knots will allow oil to pass under them

• Storing the recovered oil and waterStoring the recovered oil and water

Use oil spill dispersantsUse oil spill dispersantsLockheed Electra carries 15 tonnes of dispersant

Cessna F406Cessna F406 1.5 tonnes dispersant1.5 tonnes dispersant

Dispersant sprayingDispersant spraying

• Dispersants can be sprayed from ships Dispersants can be sprayed from ships and aircraftand aircraft

• Spraying dispersant from aircraft is the Spraying dispersant from aircraft is the MCA’s preferred active oil spill response MCA’s preferred active oil spill response optionoption– Aircraft can get to anywhere in the UKPCZ Aircraft can get to anywhere in the UKPCZ

quicklyquickly– Large areas of spilled oil can be sprayed Large areas of spilled oil can be sprayed

rapidlyrapidly

The purpose of using dispersantsThe purpose of using dispersants

• Oil spill dispersants are used to rapidly Oil spill dispersants are used to rapidly disperse the spilled oil into the sea before disperse the spilled oil into the sea before it drifts into shallow water or hits the it drifts into shallow water or hits the shoreline where most damage occurs shoreline where most damage occurs

• Dispersants have limits: Dispersants have limits: – They will not ‘work’ in some cases,They will not ‘work’ in some cases, – They are not an appropriate oil spill They are not an appropriate oil spill

response method in other casesresponse method in other cases

The BENEFITS of dispersant useThe BENEFITS of dispersant use

• The successful use of oil spill dispersants The successful use of oil spill dispersants will transfer spilled oil from the surface of will transfer spilled oil from the surface of the sea into the water column as fine oil the sea into the water column as fine oil droplets droplets

• Most, but not all, of the dispersed oil will Most, but not all, of the dispersed oil will eventually be biodegraded by naturally eventually be biodegraded by naturally occurring organismsoccurring organisms

• Dispersant use can be Dispersant use can be more rapidmore rapid, , more more effectiveeffective and and less costlyless costly than other options than other options

The RISKS of dispersant useThe RISKS of dispersant use

• Marine organisms will be exposed to Marine organisms will be exposed to elevated concentrations of dispersed oilelevated concentrations of dispersed oil

– The consequences depend on degree of The consequences depend on degree of exposure(dispersed oil concentration and exposure(dispersed oil concentration and exposure time) and species affectedexposure time) and species affected

– There must be room (water volume) and time There must be room (water volume) and time for dilution of dispersed oil to low levelsfor dilution of dispersed oil to low levels

Regulations about dispersantsRegulations about dispersants

• Dispersants cannot be sold or used in the Dispersants cannot be sold or used in the UK unless they have first been tested for UK unless they have first been tested for toxicity and effectivenesstoxicity and effectiveness

• DEFRA is licensing authority for England DEFRA is licensing authority for England and acts on behalf of National Assembly and acts on behalf of National Assembly for Wales. In Scotland, the FRS (Fisheries for Wales. In Scotland, the FRS (Fisheries Research Service) act on behalf of Research Service) act on behalf of SEERADSEERAD

Toxicity issuesToxicity issues

• Modern dispersants are less toxic than the Modern dispersants are less toxic than the oil they are used to disperseoil they are used to disperse

• Oil dispersed into the water column may Oil dispersed into the water column may cause toxic effects on some marine cause toxic effects on some marine creaturescreatures– Risk is very small if water is more than a few Risk is very small if water is more than a few

metres deep and if there is good water metres deep and if there is good water exchangeexchange

Regulations about dispersant useRegulations about dispersant use

• It is illegal under FEPA85 to put chemicals It is illegal under FEPA85 to put chemicals into the sea anywhere in the UK EEZ. into the sea anywhere in the UK EEZ. Exemptions are made for the use of oil Exemptions are made for the use of oil spill dispersantsspill dispersants

• DEFRA (or SEERAD – FRS) must be DEFRA (or SEERAD – FRS) must be informed during oil spill contingency informed during oil spill contingency planning to ensure dispersant use will be planning to ensure dispersant use will be approved. They will consult with other approved. They will consult with other relevant organisationsrelevant organisations

Regulations about dispersant useRegulations about dispersant use

• DEFRA / SEERAD must give prior DEFRA / SEERAD must give prior approval for every use of dispersant that approval for every use of dispersant that occurs within 1 nautical mile of the 20 occurs within 1 nautical mile of the 20 metre depth contourmetre depth contour

• All dispersant use must be documented All dispersant use must be documented and reported to DEFRA / SEERAD - FRSand reported to DEFRA / SEERAD - FRS

Will dispersants work?Will dispersants work?

• Dispersant will disperse most crude oils for Dispersant will disperse most crude oils for a period of timea period of time– The spilled oil “weathers” and becomes The spilled oil “weathers” and becomes

resistant to the action of dispersantsresistant to the action of dispersants– This is known as the “window of opportunity” This is known as the “window of opportunity”

for dispersant use and depends on oil type for dispersant use and depends on oil type and prevailing conditionsand prevailing conditions

• Dispersant will not work on some Heavy Dispersant will not work on some Heavy Fuels Oils in calm conditionsFuels Oils in calm conditions

Summary on dispersantsSummary on dispersants

• Modern oil spill dispersants can be very Modern oil spill dispersants can be very effective, but they do have limitseffective, but they do have limits

• Dispersant toxicity is not an issue, but Dispersant toxicity is not an issue, but dispersed oil toxicity might bedispersed oil toxicity might be

• Dispersants should be used rapidly, Dispersants should be used rapidly, sprayed accurately and used with sprayed accurately and used with professional adviceprofessional advice