About the Authors: Richard C. Ringwald, PE, brought 30 years' experience as a heavy construction/highway contractor and engineer to this publication. He was an American Institute of Constructors board member, an arbitrator for the American Arbitration Association, and taught heavy construction at Iowa State University in the Department of Civil and Construction Engineering. Mr. Ringwald received numerous awards, including Outstanding Educator from the AGC and Outstanding Professor from the ISU Engineering Council. Francis J. Hopcroft, PE, is a noted expert on hazardous waste management and disposal, a consultant to numerous firms and government agencies, and a professor of Environmental Engineering at Wentworth Institute of Technology in Boston, MA. For over 60 years, RSMeans has been the leading publisher of construction cost data and reference books. The company services over 250,000 construction professionals throughout North America. Clients include contractors, architects, engineers, facility managers, developers, appraisers, educators, and municipal and government agencies. Means also provides electronic data, consulting services, and seminars.