Weeks Island Strategic Petroleum Reserve Storage Site, Louisiana

Once part of the nation's emergency oil stockpile, until it was decommissioned beginning in 1994, due to concerns over the structural integrity of the storage cavern's roof. The site was purchased in the 1970's from the Morton Salt Company. Morton's salt mining operations produced a series of underground caverns and rooms, making the Weeks Island site the only mechanically mined storage facility within the larger Strategic Petroleum Reserve system. The resulting two-level rooms were up to 70 feet high, with 100-foot salt pillars supporting the roof. Steel-reinforced concrete bulkheads separated the oil storage levels from the equipment areas. The mine was over half a mile wide at an average depth of 700 feet below sea level. Oil filling began in October of 1980, and was completed by 1982, by which time 72.5 million barrels of oil had been stored. Gradually over a number of years, various symptoms began to appear (e.g. sinkholes), which suggested that the stability of the salt dome's roof was at risk, due to increasing groundwater infiltration caused by mining-induced fractures in the salt. In 1994, the decision was made to decommission the site, and by 1999, the majority of the oil had been transferred to other SPR facilities, at a total cost of almost $100 million. The site connects to the St. James terminal by pipeline. Most of Weeks Island is owned by the Morton Salt Company, which continues to mine salt there. Dow Chemical Company operates a chemical vapor deposition facility on the island, which is part of its Optical and Ceramic Technologies division. In addition, Alta Mesa Holdings, LP, a privately held oil and gas exploration company, operates a number of wells on the island, which had previously been owned by Shell Oil Company. These businesses  represent the island's only development.