r and has published on that topic. Since 1984, he has expanded his interests and activities to include devel- opment of a broader range of ground water quality protection poli- cies and programs. Acknowledgments I would like to thank engineers Duff, Rosenberger, Fagan, Breese, and McGuiness for developing materials which have enhanced the substance of this book. Preface About one in every four new houses being constructed makes use of an onsite septic system to treat and dispose of household waste- water. Too many of these systems do not do the job they are built to do. Failure takes the form of unpleasant and health-threatening sewage on the surface of the ground. It takes the form of sewage backing up into the plumbing fixtures inside the house. It takes the form of polluting the ground water destined to enter someone's well. Failed onsite household wastewater disposal systems are becom- ing an increasing problem over much of the country as homes are constructed in rural areas unsuitable for conventional onsite sys- items. Two-thirds of the nation's land area is unsuitable for septic system installation and use. The septic tank installer who constructs a septic system inadequate for these sites may be asking for a critical review of his contractor's license. The homeowner who puts in an expensive but "environmentally responsible" system may be throw- ing money down the drain. The land developer who sells lots in these areas without providing a warning to consumers may spend some time in court. The governmental regulator who approves inadequate systems may spend some unpleasant time in his or her supervisor's office. The information herein is presented to prevent these sorts of problems as well as to expand the land area which can be safely developed through the use of modern septic system technology. Even the most experienced installer of septic systems may not be able to put in a functional system which is significantly different in form and substance from those he has been installing all his life, particularl