The Grand Isle and Vicinity, Louisiana, project is located at Grand Isle, a low-lying inhabited barrier island located along the Gulf of Mexico in Jefferson Parish, Louisiana, approximately 50 miles south of New Orleans, LA, Appendix B, Plate 1. The island extends approximately 7.5 miles along the gulf shore generally in a northeast to southwest direction, and is approximately 0.75 mile wide at its center. Natural elevations range from approximately three to five feet National Geodetic Vertical Datum (NGVD) along the gulf shore to sea level marsh along the bay shore of the island. The population of the town is 1,541 (circa 2000 census); during fishing season the population swells to over 12,000 people. Major businesses are fishing, tourism and oil exploration. Grand Isle serves as ExxonMobil's primary marine and helicopter base for its eastern Gulf of Mexico oil and gas operations. ExxonMobil Pipeline Company, a subsidiary of ExxonMobil, also has operations on the island. This represents an important link in the nation's energy supply.