Page images
PDF
EPUB
[blocks in formation]

Oil slicks from unidentified sources are not positively related to

offshore drilling, transportation, or production.

There is evidence

of natural oil seepage in the Gulf of Mexico, first recorded in 1906, long before oil development activities were initiated, and seepage still persists in oil prone areas. It is possible that these natural seeps could be the source of some slicks classified as being from an "unidentified source". Other possibilities are ships bilges and

tanker cleanings.

We are optimistic about the industry's performance in cleaning up its routine operations and decreasing the amount of chronic spillage. The trend becomes obvious when total minor spills in barrels per month are plotted against time, as has been done in Figure 49 . The smooth curve represents a constant percentage (1.93%/mo.) decline based on the plotted data. During the period 1970-73, total oil and condensate production varied by less than 13%, whereas the constant percentage decline curve represents a decrease in minor spill volume of almost 60% over the same period.

[blocks in formation]

If a total of 8,680 bbl. of petroleum liquids were spilled during the

years 1970-73, and 1,488,242,300 bbl. were produced during the same period, the spillage rate would be 0.000583%.

Projecting this rate

to the present proposal, where maximum production is estimated at 4,380,000 bbl./year, it seems valid to predict a maximum minor spill level at less than 25 bbl./yr. If the downward trend of minor spill volumes, as shown in Fig. 49, continues, the figure will be somewhat smaller. By definition, the maximum size of a single minor spill, of course, is less than 50 bbl.

[ocr errors][merged small]

During the period July 1, 1962 through June 30,

1971, the Coast Guard recorded 24 incidents of collisions

between vessels and fixed platforms.

Total damages were estimated

to be about $0.4 million to vessels and $3.4 million to the structures. Only four injuries and no deaths were reported. Of these, eight accidents involved vessels of over 1,000 gross tons. These eight accidents accounted for $87 thousand of vessel damage (only four vessels reported damage) and over $3.2 million damage to platforms and no injuries or deaths reported. Five of these accidents occurred at night (three within two hours of midnight) and two during day-light. All of the eight major accidents

occurred outside established shipping fairways and anchorage areas and only three were less than five miles from these established areas. At least five of the accidents involved foreign flag vessels. The worst of these eight accidents occurred in 1967 when a 11,600 ton foreign flag cargo vessel collided with a platform in Ship Shoal Area Block 214 at 1:30 a.m. during heavy rain, poor visibility, 45 knot winds and 15-20 foot seas. The vessel escaped with damages estimated at $12,000 but damages to the platforms were of the order of $1.1 million or 1/3 of the total damages to platforms in all eight accidents.

Nearly

one year following this collision a blowout of gas and condensate

occurred on this platform.

There was a minimal amount of oil

spilled because the well was producing gas.

The remaining 16 incidents of collision between vessels (less than 1,000 gross tons) and platforms caused more damage ($290 thousand) to the vessel than to the platforms ($100 thousand). Causes were assigned as 2-weather, 8-vessels and 6-platforms; the platforms causes were further defined as 3-equipment failures, 2-insufficient or improper lighting and l-improper maintenance.

During the time period 1957-1973, the Geological Survey recorded only one significant spill of oil, 2,560 bbl., associated with ship-platform collisions, as discussed in subsection 2.b. (6) above.

e.

Accidental Deaths and Injuries on Oil Industry
Structures and Vessels

Information supplied by the U.S. Coast Guard

reveals that a total of 101 individuals were killed as a result
of accidents involving construction, supply, and drilling
vessels, workboats, mobile drill rigs, and artificial islands
in the Gulf of Mexico and adjacent navigable inland waters
during the period 1964-1973. Of these 101 deaths, approximately
67 occurred in water approximately equal to the Federal OCS area.
Table 37 on the following page, provided by the Coast Guard,

shows these casualties by source and year. These figures do not
include deaths resulting from accidents in which no vessel or
rig damage occurred (i.e., persons falling or knocked overboard,
crushed by drilling equipment, etc.). Partial figures for fiscal
year 1967 through 1973 indicate that approximately 36 persons
were killed in oil operations in the Gulf of Mexico (both inland.

« PreviousContinue »