bayou bonfouca

BAYOU BONFOUCA

The Bayou Bonfouca Superfund Site is in Slidell , St. Tammany Parish, Louisiana . The site occupies 54 acres and is located south of West Hall Avenue and north of and adjacent to Bayou Bonfouca. The site is bordered on the west by a creek and wooded land, on the east by a drainage ditch and commercial property, and wooded land/residential areas to the north (across West Hall Avenue) and south (across the bayou). In 1882, a creosote plant began operating at the Bayou Bonfouca site. Over the years, the plant operated under several owners including the New Orleans and North Eastern Railroad, Southern Creosoting Company, Gulf States Creosoting, American Creosote Company, and American Creosote Works, with final ownership residing with the Braselman Corporation. During the plant’s operation, numerous releases of creosote occurred through spills, runoff, and possibly discharges. In the early 1970s, a fire occurred at the plant; during the fire, several large storage tanks were ruptured, causing creosote to flow onto the site and into the bayou. Between 1970 and 1972, the plan t was disassembled, leaving behind a few building shells and foundation slabs. Wood - treating operations at the site ceased at this time. Approximately 1.5 miles of scenic Bayou Bonfouca were biologically sterile due to severe creosote contamination in bayou sediments and in the water column. Creosote contamination was so concentrated that it injured or killed aquatic animals and waterfowl, and posed a significant hazard to recreational users. The principal pollutants found at the site were PAH compounds associated with creosote. The contaminants of concern we re: benzo(a)pyrene, benzo(a)anthracene, benzo(b)flouranthene, benzo(k)flouranthene, indeno(1,2,3 - cd)pyrene and chrysene. These constituents were identified in surface soils, onsite ground water, offsite ground water, and in bayou sediments. Dense Non - Aqueous Phase Liquids (DNAPLs) were also identified in the ground water beneath the southern portion of the site, beneath the east drainage ditch, and on the south side of the bayou under portions of the residential subdivision. Approximately 750 residents live within one mile of the site . The nearest residence to the site is a bout 400 feet across the bayou to the southwest. The nearest drinking water well is approximately 1/4 mile northeast of the site. Two RODs (August 15, 1985 and March 13, 1987) , one ROD Amendment (July 20, 1995) , and one Explanation of Significant Differences (February 5, 1990) have been issued for the Bayou Bonfouca site. The remedy included the dredging of Bayou Bonfouca contaminated sediments , onsite incineration of contaminated soils and sediments , and extraction and treatment of contaminated ground water . An Explanation of Significant Difference was released to reflect significantly greater waste volumes than previous estimates resulting in remedy selection of onsite incineration of wastes after careful examination of bio treatment , underwater capping, and other alternatives. The cleanup detoxified over 170,000 cubic yards of contaminated sediment, treated approximately 17,600,0 00 gallons of contaminated ground water, and recovered about 44,500 gallons of creosote oil. A mile and a half of the Bayou was restored for aquatic life, as well as human recreational and residential use. A public boat launch was installed by the City t o allow public access to this beautifully restored area.