Environmental Impacts of a Major Marine Oil Spill

Prepared by

Stafford ReidEnvironmental Emergency Planner

Enforcement and Environmental Emergencies Branch

BC Ministry of Water, Land and Air Protection

Presentation Outline

Major Marine Oil Spill Incidents Oil Spill Risk In British Columbia Oil Types and Characteristics Oil Behaviour (Fate and Effects) Oil Impacts A Case Study - Exxon Valdez Coastal Inventory and Oil Sensitivity Mapping Shore Cleanup and Assessment

Torrey Canyon - England (March 1967)

A Liberian-registered tanker en route from the Persian Gulf was stranded by an error in ship manoeuvring, releasing 93,000 tonnes of crude oil. Contaminated 300 kilometres of both England and France.

Amoco Cadiz - France (1978)

A Liberian-registered tanker en route to England grounded on a reef off the coast of Brittany (France) and releasing 260,000 tonnes of crude oil. Contaminated 400 km of coast. Took six months to collect and dispose of the drifting oil.

Sea Empress - Wales (February 15, 1996)

The single-hulled Liberian oil tanker ran aground on St. Ann’s Head at the mouth of Milford Haven estuary, Wales, rupturing several tanks. It released 72,000 tonnes of light North Sea Crude.

Braer - Scotland (January 5, 1993)

An 18 years old, American owned, but Liberian-registered, oil tanker that ran aground at Garth Ness in the Shetlands in severe weather conditions. Cause was complete engine failure. Spilled its entire cargo of 85,000 tonnes of North Sea Crude.

Exxon Valdez - United States (March 24, 1989)

A US-flagged tanker en route to Long Beach California wrecked on Bligh Reef in Prince William Sound, Alaska due to Captain error. Eight of the eleven tanks damaged, releasing 41,000 tonnes of Alaska Northslope Crude Oil. Contaminated 1,900 kilometers of coast.

Nestucca - United States (December 23, 1988)

The fuel barge Nestucca and its tender tug Ocean Service collided of the mouth of Grays Harbour, State of Washington. An estimated 890 tonnes of heavy Bunker C oil spilled from the ruptured barge. The oil drifted past Cape Flattery and stranded along the west coast of Vancouver Island, British Columbia.

Tenyo Maru - United States (July 22, 1991)

Off the entrance to the Juan de Fuca Strait, the Japanese fishing vessel Tenyo Maru and Chinese freighter Tuo Hai collided. The Tenyo Maru sank, releasing 365 tonnes of bunker fuel. The slick travelled southwest to the State of Washington’s Cape Flattery

New Carissa - United States (February 3, 1999)

A Japanese-owned, but Panamanian-flagged bulk carrier on its way to Coos Bay, Oregon (US) lost anchor during storm conditions and grounded outside of Coos Harbour. It held 1,490 tonnes of bunker fuel, spilling 268 tonnes when it broke in half.

Kuroshima - United States (November 26, 1997)

A 368 foot seafood freighter broke away from its anchorage during a severe storm and ran aground spilling 145 tonnes of Bunker C oil. Contaminated approximately 10 kilometres of shoreline of Summer Bay on the Aleutian Island of Unalaska.

Quantities of Oil Spilled 1970 - 1999

Spill Trend - 1970 to 1999

Oil Barge & Tanker Routes

Nestucca

Exxon Valdez

The Great Circle Route - Major Vessels

New Carissa

Kuroshima

Tenyo Maru

Relative Spill Risk - British Columbia

Oil Tankers (e.g. US TAPS)

Risk = Function of Probability & Consequences

Major Vessels (e.g.Cargo, Container, Bulk Carriers)

Bulk Oil Barges

Fuel Handling Facilities

High Probability, Low Consequences

Low Probability, High Consequences

Spill Scenario 1 - Outer Juan de Fuca Strait

Spill Scenario 2 - Rosario Strait

Fate and Effect of Spilled Oil

Fate & Affect by Oil Type

DENSITY EXAMPLES

Group I less than 0.8 Gasoline, Kerosene

Group II 0.8 - 0.85 Gas Oil, Abu Dhabi Crude

Group III 0.85-0.95 Arabian Light Crude, North Sea Crude

Group IV greater than 0.95 Heavy Fuel Oil, Venezuelan Crude Oils

Impacts of a Major Oil Spill

Destroys Marine Life Destabilizes Marine Communities Degrades Shore Amenities Harms Economic Activities Impacts Human Welfare

Destroys Marine Life

Physical contamination and smothering are primary mechanisms that adversely affecting marine life - particularly inter-tidal organisms. Oil can also change the physical characteristics of a habitat.

Clean-up activities can add to these effects by crushing, removing, and damaging marine life.

Birds and mammals suffer the greatest acute impact when they meet the oil/water interface and become contaminated. Reduction in thermal capability, and directed toxicity from fumes and ingestion are the greatest causes of mortality.

Destabilizes Marine Communities and Populations

Marine communities, such as planktonic waters, wetlands (estuaries/marshes), kelp-beds and mud-flats, and marine populations such as seabirds, seals sea otters, and whales have variable resiliency to oil spills - from highly tolerant (plankton, kelp beds) to very intolerant (estuaries and sea otters).

Impacts to communities and populations are very difficult to measure due to lack of scientific methods to measure, long-term, sub-lethal, and chronic ecological impacts

Degrades Shore Amenities

Contamination of coastal amenity areas is a common feature with many marine oil spills, leading to public disquiet and concern regarding impacts to boating, sun-bathing, swimming, angling and other recreational pursuits.

The prevailing question is how much and how long of an impact? The degree of impact to recreation is largely based on the season it occurred.. Summer being the highest impact period due to recreation and tourism.

Harms Economic Activities

Economic activities that can be adversely affected by an oil spill include: tourism, hotel and restaurant businesses, dive and fishing charters, rentals, marina operations. There can also be direct impacts to commercial fishing and aquaculture due to closures or concerns about tainted products.

The impacts to a coastal communities economic activities can be accentuated by media press, beyond the actual impacts to the recreational and commercial opportunities.

Impacts Human Welfare

A spill’s impact to human welfare is often under-rated. Coastal communities, and public in general, are deeply passionate about a safe, clean marine environment. There is no tolerance for accidental spills of oil of any quantity. As such a marine oil spill accentuates this passion, often beyond rationale thinking.

During an incident, public stress and anxiety prevail over the long-term economic uncertainty of lost welfare. In addition, a large influx of spill money can divide a communities from those the volunteer from their “hearts” and those the offer their services for a “fee”.

Spill Impact Recovery

The recovery of the marine environment from the effects of a spill is generally thought to be “a return to the precise conditions that preceded the oil spill”. However, this is very unlikely to happen. As such, the measurement of spill recovery is based on a comparison of unoiled sites with oiled sites of similar ecological characteristics.

A Case Study - Exxon Valdez

This 1989 crude oil spill occurred in the most biological active season

More than 1,900 kilometres of coast oiled

3,500 to 5,500 sea otter died

200 harbour seals

144 species of dead birds collected

Estimated bird loss ranges from 260,000 to 580,000

60 to 70% colony reduction in Common and Thick-billed Murres

Case Study - Oil Reduction in Intertidal Shorelines

Intertidal habitats of the Prince William Sound have shown surprisingly good recovery. Many shorelines that were heavily oil and then cleaned now appear much as they did before the spill. There are, however, still oil vestiges 10 years later.

Surface oiling a study sites in Prince William Sound

Case Study - Remaining Impacts to Intertidal Habitats

Remaining impacts include:

some deeply penetrated oil continue to leach from a few beaches, and weathered remnants of oil in a few sites

some intertidal animals, such as mussels, are still contaminated

some rock sites stripped by aggressive (e.g. high-pressure, hot-water) cleaning are still bare

a few rich clam beds that suffered high mortality have not fully recovered.

Case Study - Remaining Impacts to Wildlife

Though a high number of individual animals may have been killed, the actual initial impacts to communities (populations) of salmon, sea otters, harbour seals and sea bird was low. Indications show that wildlife species populations have recovered within their natural range of variability.

Case Study - Restoration Focus

The marine environment with its natural resiliency and ability to recover required little work in restoration, beyond initial cleaning. The bird and wildlife populations are more threatened by upland activities such as logging, which destroyed Marbled Murrelet nesting areas, bear foraging sites, and salmon habitats.

Settlement funds - billions of dollars - enable purchase of a million acres of forest lands to ensure a sustainable environment. These purchases recognized that one can't draw a line at the ocean’s edge.

Case Study - Some Lessons Learned

Natural flushing action of waves and storms is far more efficient and better in restoration than mops, hoses, and rakes.

Wildlife rescue and rehabilitation efforts had a marginal beneficial effect on the recovery of bird and mammal populations.

Conventional wisdom is that habitat protection is a better cure than damage mitigation, no matter how extensive or tender.

Case Study - Conclusions

From an ecological perspective, the impacted area of the Prince William Sound from the Exxon Valdez has shown surprising resiliency - an ability to return to its natural state within the range of natural variability. There are still environmental scarring.

From a social perspective, the impact of the Exxon Valdez oil spill on those people who lived and experienced the event remains as fresh in their minds as the day it happened. People still hurt.

In conclusion, the environment has a greater resiliency to an oil spill than people.

British Columbia’s Ecological Approach to Marine Oil Spill Management

The Exxon Valdez as well as many other major oil spills has enable British Columbia to learn from the experiences of what to do, or more importantly what not to do.

These lessons are reflected in two main areas that the Province focuses on:

•Coastal Inventory and Shoreline Oil Sensitivity Mapping

•Shore Cleanup and Assessment

Coastal Inventory and Shoreline Oil Sensitivity Mapping

British Columbia has one of the most extensive and sophisticated coastal inventory and shoreline sensitivity mapping program in the world.

Red = High Oil Sensitivity

Coastal Mapping

Shoreline Oil Sensitivity Mapping ensures the most environmentally-sound and effective methods are used. Based on technical, not political evaluations

Shoreline Cleanup and Assessment

When a spill occurs, Canada utilizes the Shoreline Cleanup and Assessment Team (SCAT) process adopted from Alaska to determine when and how each individual shoreline will be cleaned based on geomorphological, ecological and archaeological factors.