Portal de Periódicos da CAPES

AERIAL APPLICATION OF DISPERSANTS AT THE IXTOC I SPILL

1981; Atlantis Press; Volume: 1981; Issue: 1 Linguagem: Inglês

10.7901/2169-3358-1981-1-259

2169-3366

Gordon P. Lindblom, Bruce D. Emery, Miguel A. Garcia Lara,

Oil Spill Detection and Mitigation

ABSTRACT Chemical dispersants were a valuable part of the response to the Ixtoc I blowout and spill. Use of these chemicals effectively prevented floating oil from entering near-shore environments, particularly those areas that represent the main migration routes for shrimp larvae. Selective aerial treatment of oil masses that threatened locations 20 to 25 miles (32 to 40 km) from shore was carried out along over 1,000 miles (1,600 km) of coastline. Oil treated ranged in thickness from about 50 to 75 μm to 0.15 to 0.2 mm. This oil appeared from the air as vast silver sheets, orange-brown emulsions, and darker brown accumulations, and represented oil concentration of about 800 to over 3,000 bbl/mi2 (49 to 184 m3/km2). All were successfully treated even after being on the water for 4 to 6 months. The aircraft used were Douglas DC-6B and DC-4 spray planes which had previously been tested in dispersant spraying during overland projects. These airplanes, capable of carrying over 3,000 gal (11,356 l) per flight, operated from 5 different bases during the work, and flew more than 1,000 hours on 493 missions, with an average coverage of about 2 mi2 (5.1 km2) per spray flight. Dispersant dosage varied from 2 to 4 gal/acre (18 to 37 l/ha) over approximately 1,000 mi2 (2,590 km2) of sea surface. This paper presents details of the spraying operations, the logistical concerns of the project, and aircraft operating and navigational procedures. It also addresses the economic implications of this operation for future contingency planning and spill response.