Environmental impacts and regulatory policy Implications of spray disposal of dredged material in Louisiana wetlands

Abstract

The capabilities of a new wetland dredging technology were assessed along with associated newly developed state and federal regulatory policies to determine if policy expectations realistically match the technological achievement. Current regulatory practices require amelioration of spoil bank impacts upon abandonment of an oil/gas well, but this may not occur for many years or decades, if at all. Recently, a dredging method (high‐pressure spray spoil disposal) was developed that does not create a spoil bank in the traditional sense. Its potential for reducing environmental impacts was recognized immediately by regulatory agencies for whom minimizing spoil bank impacts is a major concern. The use of high‐pressure spray disposal as a suitable alternative to traditional dredging technology has been adopted as policy even though its value as a management tool has never been tested or verified. A qualitative evaluation at two spoil disposal sites in saline marsh indicates that high‐pressure spray disposal may indeed have great potential to minimize impacts, but most of this potential remains unverified. Also, some aspects of current regulatory policy may be based on unrealistic expectations as to the ability of this new technology to minimize or eliminate spoil bank impacts.

Keywords:

• dredging
• environment
• Louisiana
• policy
• wetland

Notes

Current Address: Louisiana Geological Survey, P.O. Box G, Baton Rouge LA 70893.

Current Address: Chesapeake Biological Laboratory, University of Maryland Center for Environmental and Estuarine Studies, Box 38, Solomons, MD 20688–0088.