Island Rincon --ARCO production island--man-made, approximately 1/2 

 mile off shore, 10 miles north of Ventura, California. It is connected to 

 shore via a pile supported trestleway. Power is supplied via electrical lines 

 from shore. Measurements included airborne, structureborne, and underwater 

 sound. Underwater measurements were made from a hydrophone lowered from the 

 trestleway, and also overside from a small, drifting boat. All measurements 

 were near the island in water depths less than 50 feet. Here also, the 

 interim recorder-measurement system used at Platform Holly was used. 



2. Cook Inlet, Alaska, June 1980 



Ocean Bounty --ODECO operated, leased by ARCO, semi-submersible, 

 located in Lower Cook Inlet, approximately 40 miles southwest of Homer. The 

 platform is mounted on eight legs supported by a pair of submerged cylindrical 

 hulls 26 feet in diameter. The rig is anchored by chains in an eight point 

 moor in water 300 feet deep. Platfot^n elevation is maintained by adjusting 

 water level in ballast tanks. Prime power is derived from unmuffled diesel 

 engines. Measurements included airborne, structureborne, and underwater 

 sound. Underwater measurements were from a drifting 50 foot trawler, at 

 ranges from 10 to 400 yards from the platform. Hydrophone depths varied from 

 20 to 110 feet. 



Platform King Salmon --ARCO production platform located in Upper Cook 

 Inlet, near Kenai, Alaska. It is a quadripod with legs 10 feet in diameter. 

 Water depth is approximately 60 feet. Primary power is gas turbine. 

 Measurements included airborne, structureborne, and underwater sound. 

 Underwater measurements were obtained during periods near slack tide by 

 lowering the hydrophone from the structure about midway between legs 1 and 2. 

 Hydrophone depths varied from 10 to 35 feet. 



Pl atform Spark --ARCO production platform located in Upper Cook Inlet 

 near Kenai, Alaska. It is a tripod with legs 15 feet in diameter. Water 

 depth is approximately 75 feet. Primary power is gas turbine. Measurements 

 included airborne, structureborne, and underwater sound. Underwater 

 measurements were taken during near slack tide with the hydrophone suspended 

 from the edge of the platform approximately midway between legs 2 and 3. 

 Hydrophone depths were varied from 20 to 50 feet. 



3 . Atlantic City, New Jersey, August 1980 



Oc ean Victory --ODECO operated, leased by Tenneco, semi-submersible, 

 located near Baltimore Canyon approximately 100 miles out of Atlantic City, 

 New Jersey. This rig is nearly identical to the Ocean Bounty described 

 earlier. It is anchored in approximately 500 feet of water. Measurements 

 were made during drilling at a depth of approximately 15,000 feet. Primary 

 power was from unmuffled diesel engines. Measurements were made of airborne 

 sound (one location) and underwater sound. Underwater sound measurements were 

 made by a hydrophone suspended from the deck edge at the bow location, 

 approximately equally distant from the two submerged hulls. Hydrophone depths 

 were 20 and 120 feet. 



E-4 



