Our History

Clean Soils Environmental, Ltd. (CSE) was founded in 1989 by Denise M. Prosser who was then attending New Hampshire College to obtain her MBA. Ms. Prosser’s final project entailed researching new business horizons to develop a family business. Through her research, she discovered an opportunity in the environmental consulting field, which was approximately 5 years old at the time with a vast growth potential. Taking her research project a step further, Ms. Prosser subsequently teamed up with Mr. William H. Mitchell, Jr., who had previous environmental engineering experience, and CSE was organized and incorporated. Mr. Mitchell now serves as the president of CSE, with Ms. Prosser in the role of Business Manager and Chief Financial Officer. In 1993, the Massachusetts Department of Environmental Protection (MassDEP) restructured the oil and hazardous waste cleanup program. In an effort to reduce government oversight and speed up the remediation of contaminated sites, MassDEP partially privatized the cleanup program by developing the Licensed Site Professional (LSP) program. The LSP program and subsequent LSP Association has streamlined the cleanup process by allowing LSPs to conduct assessments and oversee cleanups at contaminated sites while minimizing delays associated with MassDEP. Mr. Mitchell was among the first in the country to obtain a full LSP designation from the Massachusetts Board of Hazardous Waste Site Cleanup Professionals. Since 1993, CSE has successfully completed hundreds of projects and has serviced a large and diverse client base.