perry

us & ministry

aerial application of oil dispersant

(due to the large file size, a number of great pictures had (due to the large file size, a number of great pictures had to be removed from this presentation. We apologize.)to be removed from this presentation. We apologize.)

present fleet

TURF & EYES : the story continues

pause

the Sea Empress incident :

dispersant spraying at its most effective

case study : Sea Empress

Workshop on the application of dispersant in the Dutch part of the North SeaWorkshop on the application of dispersant in the Dutch part of the North Sea

success due to number of factors

The success of the spraying operation The success of the spraying operation at the Sea Empress incident at the Sea Empress incident

was due to a number of factors : -was due to a number of factors : -The primary ‘clean up’ response for dealing with oil spillage

in UK waters was (and still is) aerial dispersant spraying, due to the length and nature of the coastline

Legislation for the use of dispersants had been in place for several years; the method and rules of approval had been well established, practised and refined during exercises and incidents

So only local approval and confirmation was required

Equipment was readily available close at hand

Personnel were an experienced & motivated team

Size of the spill, location and type of oil were optimal

Weather conditions were suitable for effective spraying

EQUIPMENT AND PERSONNELEQUIPMENT AND PERSONNEL

Centrally-located surveillance and spray aircraft together Centrally-located surveillance and spray aircraft together with crews ( with crews ( including engineers and ground loading

teams) were available on permanent standby:) were available on permanent standby: 30 minutes 30 minutes call during the day, call during the day, and 2 hours at nightand 2 hours at night

Aircraft arrived at the forward base loaded with Aircraft arrived at the forward base loaded with dispersant, and sufficient stock was stockpiled dispersant, and sufficient stock was stockpiled

locally to enable operations to continue without delaylocally to enable operations to continue without delay

Forward operating airfields near to the incident Forward operating airfields near to the incident had been pre-identifiedhad been pre-identified

equipment & personnel 1

EQUIPMENT AND PERSONNELEQUIPMENT AND PERSONNEL

Loading pumps and safety equipment were held permanently on the spray aircraft and functionally checked weekly

equipment & personnel 2

Three main, centrally located, dispersant stockpiles were mobilised and the IBC tanks moved to the forward base

Aircrew and ground support teams were well trained and practised – in addition to operations, drills were held monthly and deployment exercises twice a year

size & nature of spillsize & nature of spill9 discrete oil spills over a period of 6 days9 discrete oil spills over a period of 6 days

Biggest was 20,000t and the smallest 2,000tBiggest was 20,000t and the smallest 2,000t

Total spillage 72,000 tonnes of Forties blend crude and Total spillage 72,000 tonnes of Forties blend crude and 360 tonnes of heavy fuel oil360 tonnes of heavy fuel oil

The oil was amenable to dispersant size of spill

location & weather

LOCATION AND WEATHERLOCATION AND WEATHER

Tanker ran aground at the entrance to the harbour

Forward airfield was available close by

Weather was mostly good for dispersant use : wind speed - more than 10 knots.

sea state - breakers present (up to state 7/8)

STRATEGYSTRATEGY

Because dispersant works more efficiently on freshly spilled oil and there were regular discharges from the tanker, the strategy was :

Concentrate on freshly spilled oil first

Spray ‘weathered’ oil later, if required

STOP spraying when :-- sufficient dispersant applied- no longer effective due emulsification- slick too broken for effective spraying- weather unfavourably calm or too windy

Monitor and spray again as necessary

strategy

oil stats +PO spraying

SEA EMPRESS

70,000 tonnes spilled in total

37,000 tonnes37,000 tonnes(52%) of spilled crude oil (52%) of spilled crude oil

DISPERSEDDISPERSED

10,000 tonnes10,000 tonnesNATURALLYNATURALLY

27,000 tonnes 27,000 tonnes AFTER AERIAL AFTER AERIAL

DISPERSANT APPLICATIONDISPERSANT APPLICATION

SEA EMPRESS

70,000 tonnes spilled in total

37,000 tonnes37,000 tonnes(52%) of spilled crude oil (52%) of spilled crude oil

DISPERSEDDISPERSED

10,000 tonnes10,000 tonnesNATURALLYNATURALLY

27,000 tonnes 27,000 tonnes AFTER AERIAL AFTER AERIAL

DISPERSANT APPLICATIONDISPERSANT APPLICATION

general guidelines & SOPs

general guidelines and operating proceduresfor spraying operations

general guidelines and operating proceduresfor spraying operations

Workshop on the application of dispersant in the Dutch part of the North SeaWorkshop on the application of dispersant in the Dutch part of the North Sea

control & guidance

Control & GuidanceControl & Guidance

From start to finish, control of spraying is under the From start to finish, control of spraying is under the guidance and direction of the surveillance aircraft, guidance and direction of the surveillance aircraft, usingusing standard operating procedures.standard operating procedures.

safety of airspacesafety of airspacesafety of airspacesafety of airspace

The surveillance crew and dispersant spraying team initially determine the dimensions of the ‘safe’ operating area

Control over the ‘safe’ area is established by national emergency controlling authorities requesting restrictions over the airspace and sea area

Ideally the operating area should be kept completely clear of all other aircraft, vessels and obstructions

All spray operations are strictly daylight VFR

For example in the UK, the Secretary of State is enabled through an act of parliament to declare a ‘temporary exclusion zone’ (TEZ) around a ship or structure at sea

The National Air Traffic Services have the authority to establish a temporary danger area (TDA) to restrict flying

All aircraft movements within the TEZ and TDA are controlled by the surveillance aircraft crew

safety of airspace

initial role of surveillance crew

Initial role of surveillance aircraft crewInitial role of surveillance aircraft crew

Establish, survey and control the ‘safe’ operating area

Obtain & confirm approval to use dispersant

Confirm dispersant type

Confirm geographic & water depth constraints

Locate position of thickest oil

Determine ‘spray’ pattern

Brief, guide & direct the test spray

Assess and report the effectiveness of test spray

efficient application

The surveillance aircraft crew determine position of the thick oil within the slick either visually (seen as true colour, discontinuous true colour, or metallic appearance) or using the IR detector.

The spray pattern is then oriented to ensure that the dispersant is applied only to the thick oil, not sheens.

Visual observation can confirm the dispersant is working. The oil will spread rapidly and there will be a ‘milky’ plume

mainly at the edges.

efficient application

application

ApplicationApplication

Dispersant is delivered by aircraft fitted with approved spray systems. Aircraft normally fly

into wind at low level, 20-50 feet above the surface, at about 140 knots, depending on aircraft type

Normal dose rate 1 t of dispersant to 10 / 20 t of oil

THICK OILTHICK OIL

SHEENSHEEN

SURVEILLANCE AIRCRAFTSURVEILLANCE AIRCRAFT(700 FT – 1000 FEET)(700 FT – 1000 FEET)

SPRAY ‘OFF’ SPRAY ‘OFF’ CLIMB STRAIGHT AHEAD TO 300 FEETCLIMB STRAIGHT AHEAD TO 300 FEET

SPRAY ‘ON’SPRAY ‘ON’ LEVEL AT 30 FEETLEVEL AT 30 FEET

spray patternspray pattern

SPRAY CIRCUITSPRAY CIRCUIT

SPRAY AIRCRAFTSPRAY AIRCRAFT

CIRCUIT HEIGHTCIRCUIT HEIGHT300 FEET300 FEET

WINDWIND

spray pattern

DISPERSANT MONITORINGDISPERSANT MONITORINGVESSEL’S TRACKVESSEL’S TRACK

EffectivenessEffectiveness

THICKTHICK OILOIL

SHEENSHEEN

After the spray aircraft has cleared the area the dispersant monitoring vessel is called in by the surveillance aircraft. Data is collected in clear water, the sprayed area, and the oiled area,using UV fluorescence spectroscopy.Data is analysed and the results passed back to the surveillance aircraft

SURVEILLANCE AIRCRAFTSURVEILLANCE AIRCRAFT

AREA SPRAYEDAREA SPRAYED

If the dispersant monitoring team are not available, the dispersant effectiveness is assessed visually by the surveillance crew and passed to the response authorities

If the results are positive i.e. the dispersant is working – spraying continues and monitoring takes place at regular intervals between deliveries

effectiveness

role of surveillance aircraft crew

during main spraying operationsduring main spraying operations

Brief & direct the spray aircraft in the pattern

Direct the in-situ monitoring vessel

Monitor the area and spill between spray applications

Stop spraying when sufficient dispersant has been delivered or as required by the response authorities

main role of surveillance crew

questions

‘‘DANK U WEL’DANK U WEL’THANK YOUTHANK YOU

QUESTIONS ?QUESTIONS ?