Incident
Name: STC-101
Subject:
USCG Case History
Incident Date:
2/2/1976
Incident Location:
Chesapeake Bay, Northampton County, Virginia
Author:
USCG Case History
Latitude:
37 49 N
Longitude:
076 11 W
USCG District:
5
Product:
No. 6 Fuel Oil
Type: 4
Volume:
5959
Source:Tank Vessel
RAR: Diving coastal birds, waterfowl, shorebirds, wading birds, gulls, oysters, mussels.
Dispersants:
No
Bioremediation:
No
In-Situ Burning:
Yes
Special Interest
Topic(s): Habitat impact due to oil, wildlife impacts, volunteer response and organization, unusual or experimental cleanup techniques.
Shoreline Type(s)
Impacted: Salt marshes, riprap, piers, sand/gravel beaches.
Summary:
On February 2, 1976, the petroleum transport barge STC-101, under tow by the Allied Towing Company Tug Falcon, partially sank during stormy weather in Chesapeake Bay approximately 3.5 miles off Smith Point Light. The bow, protruding at a 30° angle, was approximately 30 to 40 feet out of the water while the stern rested on the bottom in approximately 105 feet of water. The STC-101, loaded with 19,531 barrels of No. 6 Fuel Oil, was en-route from the AMOCO Refinery in Yorktown, Virginia, to the AMOCO Terminal in Baltimore at the time of the incident.
Initially, only a small rainbow sheen, believed to be from deck machinery diesel and lube oil, was observed around the barge. Clean Water Inc. was contracted by Steuart Transportation, the barge owner, to stage pollution abatement equipment near the scene in the event of a spill during salvage operations. An underwater survey of the barge on February 4 reported no oil leaking from the barge, however, oil patches and light sheen were reported in the surrounding area on February 5. After the STC-101 was refloated on February 6 by the McLean Construction Company, the barge was intentionally grounded in Ingram Bay for dewatering operations. Extensive damage to the port side was discovered. Severe wind and weather conditions as well as poorly maintained and improperly secured cargo hatches may have contributed to the oil spillage.
After the U.S. Coast Guard Marine Safety Office Hampton Roads received several reports of oil and birds washing up on surrounding shorelines, a Federal spill was declared on February 8. On February 19, the AMOCO Terminal in Baltimore, Maryland, concluded that 5,959 barrels of oil were missing from the STC-101 barge.
Beach and marsh areas of both the eastern and western shores of Chesapeake Bay were contaminated. Large areas of dormant oiled marsh grasses were cut, leaving the root systems intact. Virginia authorities estimated that between 20,000 and 50,000 waterfowl were killed as a result of the spill.
The bulk of the cleanup was completed by mid-March. A final inspection on November 5 revealed little evidence of oil remaining in the affected areas.
Behavior:
No. 6 fuel oil is a heavy product with an API gravity that ranges from 7 to 14. A light horseshoe-shaped sheen observed around the vessel the day of the incident was believed to be diesel and lube oil from the deck machinery. An aerial survey on February 5 revealed several areas of scattered light sheen in the water between Bluff Point and Smith Point Light. Also, a sheen measuring 1 mile wide by 3 miles long with widely scattered patches of black oil was observed approximately 8-10 miles due south of the barge. On February 7, approximately 800 gallons of oil washed ashore east of the Windmill Point Marina. A large slick impacted the eastern side of the bay between Nadua Creek and Cherrystone Creek on February 8. This 71-mile distance consisted of creeks, marshes, and irregular shoreline, of which 27 miles suffered some oiling . The most adversely affected area was a 15-mile stretch between Hungar's Creek and Nassawadox Creek. Observers on a February 9 overflight reported heavy concentrations at Fleet Island on the western shore. Oil also pooled in localized areas such as Windmill Point, Cameron Marsh, and Gwynn's Island on the western shore.
Since no heavy oil impacts were observed until February 7, the heavy No. 6 oil was believed to be submerged just below the surface of the water until it reached the shore. Adverse weather conditions made the oil difficult to observe from the air. Approximately 3,980 of the 5,959 barrels of oil spilled were recovered during cleanup operations. Much of the missing oil was believed to be on marsh grass roots on the eastern shore.
Countermeasures/Mitigation: Heavy pools of oil on the sand beaches were removed using front-end loaders. This cleanup method was used only at low tide and in daylight hours. The effort was complicated by tidal exchanges covering the oiled areas with new layers of sand that created oil and sand mixtures.\\Boom was deployed around the vessel during salvage and towing operations. Containment boom was also used around the Windmill Point Marina. Booms were ineffective because of strong wind, wave, and tidal action. Vacuum trucks also proved ineffective because the oil was viscous and plugged the suction hoses. Consequently, shovels were the predominant beach cleanup tool.\\High-pressure washing was effectively used to remove oil on rocky areas, piers, and groins. High-pressure washing was also tested on marsh grass, but quickly proved ineffective due to the viscosity of the oil.\\Salt marshes on the eastern side of the bay were severely impacted. After all responsible parties agreed that it was not advisable to remove the marsh grass root system, the On-Scene Coordinator (OSC) decided to cut and remove the marsh grass while leaving the root system intact. Grass cutting was done by hand or with "weedeaters." Dry grass was spread over areas where thick oil remained in the root system, walked on to compact it into the soil, and removed using rakes and pitchforks. This slow, labor intensive process was used on ten miles of shoreline. The contaminated grass was transported to a landfill for disposal.\\Disposing of 4,000 barrels of recovered oil in landfills was not a viable option on the eastern side of the bay since the water table is close to the surface and groundwater is the primary source of drinking water in this area. The State Water Control Board, State Department of Health, and State Air Pollution Control Board decided the landfills could be used as burning sites. A brush- and tree stump-burning device consisting of a gasoline-powered forced draft blower hooked to a tractor was used to burn recovered oil. The burned residue was disposed of in the landfill. Sand/oil mixtures recovered during beach cleanup on the eastern shore were used as road fill and repair material for damage done by heavy cleanup machinery. The sand/oil mixture collected on the western shore was given to the Lancaster County Raceway for dust control use.
Other Special
Interest(s): The Chesapeake Bay Oil Spill Task Force was organized as an investigative group after the oil spill. The purpose of the Task Force was to assess cleanup activities and environmental damage, consider preventive measures, and provide input to the Attorney General's office to support potential litigation. Preliminary reports indicated that environmental damage was not as great as initially expected. A small loss of habitat in marsh grass areas resulted, but finfish and benthic organisms did not appear to be severely affected.\\The U.S. Fish and Wildlife Service estimated that 20,000 birds died as a result of this incident. A total of 8,469 dead waterfowl, mostly Horned Grebes and Old Squaw, were recovered. Forty-six dead Whistling Swan, an endangered species, were recovered. Several problems were experienced in the cleaning of live, oiled waterfowl: volunteer groups were given little or no direction or assistance in their efforts to save the birds; and the contingency plan for the area did not include provisions for bird cleaning operations. Under the National Oil and Hazardous Substances Pollution Contingency Plan, the Department of Interior's representatives and state liaison to the Regional Response Team were assigned the task of waterfowl rehabilitation. Due to poor planning and coordination by the predesignated agencies, the OSC, who did not have lead responsibility for bird cleanup operations, was constantly questioned by the public and media about bird cleanup operations.
References:
Hershner, C. and Moore, K. 1977. Effects of the Chesapeake Bay Oil Spill on Salt Marshes of the Lower Bay, Oil Spill Conference Proceedings 1977, pp.529-533.
Roland, et al. 1977. The Chesapeake Bay Oil Spill-February 2, 1976: A Case History, Oil Spill Conference Proceedings 1977, pp.523-527.
USCG On-Scene Coordinator's Report
Last Edit:
9/19/92
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