Jan 23, 2016

The great Long Cove spill of 1971


March 16, 1971  LONG COVE SPILL
From:  An Historical Review of Oil Spills Along the Maine Coast. 
Institute of the Gulf of Maine  May 14 1974

"Culminating years of minor spills presumed common to any fuel handling facility, the Long Cove spill at Searsport constitutes one of the outstanding examples of a chronic condition that has virtually eliminated a once normal and health clam community. 

A spill of volatile JP-5 (jet fuel) mixed with No. 2 fuel was discovered on March 16, 1971. Although initially reported by the U. S. Coast Guard to be "small and less  than a barrel" large quantities were found by DMR personnel flowing into tidal waters at Long Cove through a culvert and a  ditch.  By March 22 between 5,000 and 10,000 gallons had been recovered while oil covered the Little River flats some  five miles across Penobscot Bay. Aerial photographs of the slick progress were taken to show the rate of slick movement.

By March 26, the mortality area of clams in Long Cove increased from 1/3 of an acre to two acres.  During the same period sampling at Little River indicated 5 to 10 percent of the clams were dead. Only three days later, Long Cove mortalities covered 10 acres or 30 percent of the standing crop while the  Little River  area had risen to 50 percent mortalities.

Subsequently, the U. S. Air Force. owner of the oil terminal which pipes jet fuel to Limestone APB, contracted with theDepartment of Marine Resources to conduct a detailed study of the clam mortalities at Long Cove. This study estimated that the standing crop of soft clams was 23,000 bushels prior tothe spill. Sustained yield was estimated at 10,000 bushels.

By August, 1972, the reported mortality was 12,000 bushels. Oil was present in 23 percent of the 130 intertidal samples. All clams were unmarketable due to prolonged oil contamination. The Department of Marine Resources estimated that this condition may persist for many years.

As the market value of the clams in this area is estimated at $150,000 to the diggers annually on a sustained yield basis,the value of the standing crops is $345,000. Using an accepted EPA shellfish multiplier of retail value (Wong, 1969) the yearly crop would be worth as much as $4 million at 1973 values. Thus, there is a total loss of $4 million each year to the State of Maine based on the Department of Marine Resources files.

Analysis of the sediment samples at this location using gas chromotography indicates that the light fractions of oil work down into the sediments contaminating all forms of marine organisms. Also this analysis indicates that the spills have been continuing since the first spill in 1971. Unlike clams affected by sewage pollution which can be cleansed in as little as 48 hours, these clams are unsalvageable through any known techniques. Assessment of such damage to an entire community is extremely difficult since prior baseline studies rarely exist.

Histological studies of clams from Long Cove conducted by Paul Yevich of the Environmental Protection Agency for the Department of Marine Resources, showed an incidence of abnormal growths have been reported more recently in two other locations in the state where clams have been contaminated by oil. (Dow, personal communication)

According to the Director of Research at the Department of Marine Resources experiments conducted during 1973 with planting clams in both Long Is land and Long Cove and similar clam plants in uncontaminated areas show a marked increase in; mortalities in the two oil contaminated sites.


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