Results of a survey of horizontal environmental well installations

Horizontal environmental wells have been installed at various hazardous waste sites for the purpose of remediating contaminated soils and ground water. Horizontal wells provide the means to access a greater surface area of the contaminated zone and to access zones that are inaccessible by traditional remediation technologies. A survey of the horizontal environmental well industry was performed during June 1993 to determine the extent that the environmental industry has applied the new technology. The study is, in essence, an inventory of the horizontal environmental wells that have been installed. The initial results of the survey indicate that over 100 horizontal wells have been installed. Approximately 26 ground water pump and treat wells have been installed, 25 soil vapor extraction wells, and 55 other types of wells (including product recovery, air sparging, in situ stripping wells, and drains). The majority of the wells have been installed at depths of less than or equal to 8-m. vertical depth. The cost of the horizontal wells is directly related to the vertical depth of the installation, site geology, well materials, and the length of the well.