Compositon, fate and effects of producedwater discharges to nearshore marine waters

Abstract

From Conclusions: “Produced water from two platforms in Louisiana coastal waters were hypersaline brines containing complex mixtures of low concentrations of several metals, petroleum hydrocarbons, and other organic compounds. However, metals concentrations in sediments near both produced water discharges were not elevated compared to concentrations in sediments further away.

At Eugene Island, Block 105, sediments from stations 100 m or further from the produced water discharge did not contain greater than trace or background quantities of petroleum hydrocarbons. Sediments from stations 20 m from the platform contained low concentrations of petroleum hydrocarbons. Thus, chronic discharges of about 1,570 bbl/day of produced water to inner continental shelf waters with a depth of about 8 m has resulted in a low to moderate level of contamination of surficial sediments with petroleum hydrocarbons out at least to 20 m but not to 100 m from the platforms. Benthic communities may have been affected by the chronic discharges out to 20 m from the platform but not at distances of 100 m or more.

At Lake Pelgo, Tank Battery No. 1, sediments out to at least 100 m but not as far as 300 m from the platform contained petroleum hydrocarbons, probably derived from more than 40 years of produced water discharges at a rate of about 2,750 bbl/day to the shallow (2 m) protected waters of a coastal bay. Benthic communities may have been affected at distances of 20 m but not at distances of 100 m or more from the platform by the produced water discharges.”