Cooperative Environment Projects, High Island Block 24 L, Offshore, Texas
Authors: Thompson Roger R. , Honeycutt Baxter D. , Parker Jack C. 
Published: October 2008

Atlantic Richfield's concern for environmental protection has led to participation in several interesting ecological experiments. Space, along with engineering and operational assistance, is currently provided on its offshore Texas platforms in the High Island Block 24-L Field for three experiments involving shrimp and oysters. These experiments are being conducted by Texas A&M University, Ralston Purina Company and the National Marine Fisheries Service from gas production platforms that have associated brine discharges and submerged gas flares. They involve reproduction and maturation studies with shrimp, the feasibility of trapping gravid (pregnant) shrimp beneath the platforms and the feasibility of rearing oysters attached to strings suspended from the platforms. Success in these endeavors could provide a boon to commercial shrimp farming and a possible source of easily raised salt water oysters. Successful or not, they will help provide additional knowledge concerning the interaction of the offshore oil industry with its environment. This paper describes the experiments, their implications, and Atlantic Richfield's involvement.

INTRODUCTION

In the Spring of 1970, Atlantic Richfield was approached by Dr. Jack C. Parker of Texas A&M concerning possible cooperative endeavors in mariculture (the commercial culture of marine organisms). He felt that oil companies involved in offshore operations could work with mariculture researchers for their mutual benefit. In his opinion, offshore oil platforms in the Gulf offered a base from which a number of unique mariculture experiments could be conducted. The success of some of these experiments could lead to the development of other commercial uses for offshore platforms. After consultation with biologists from the National Marine Fisheries Service, Texas A&M University and Ralston Purina, Atlantic Richfield agreed to provide space on offshore structures, along with engineering assistance, for several mariculture experiments.

These experiments, involving oysters and shrimp, are being conducted on and under Atlantic Richfield's "B-EX" production platform complexes in the High Island Block 24-L Field, offshore Texas. This platform, approximately seven miles offshore and 13 miles east of High Island, Texas (Figure 1), currently produces between 90 and 100 MMCFPD and associated condensate at a rate of 450-500 BCPD. As noted in Figure 2, the shrimp and oyster experiments are located on platforms which contain brine and deck wash sumps and submerged gas flares in which small amounts of gas are dissipated by being bubbled through the water. The onshore facilities include a brine disposal line.

Table I shows an average analysis of the various brine discharge points in the field. Both average and standard deviations are given. The period considered covers 12 water analyses done between January 1, 1971 and December 31, 1971. Platform "B" discharges approximately 100 barrels of brine per day, Platform "A" approximately 550 barrels of brine per day, and the onshore production facilities 200-300 barrels of brine per day into the High Island Block 24-L Field area. Table II gives a further analysis of each discharge point and compares that to an average seawater.

The gas discharged is bubbled up through the water from a point approximately 200 feet southwest of the "B" platform.