On-site septic system technology is undergoing dramatic changes and advances with increased effort and thought placed on the effective and economical design of on-site systems. STP 1324 addresses these changes with 25 peer-reviewed papers in three sections:

Septic System Operation and Evaluation -- 7 papers, including a comprehensive inspection procedure for evaluation of septic systems; distribution box performance in septic tank-soil absorption systems; domestic wastewater and the sodium factor; and the use of low-pressure systems to provide even distribution of septic tank effluent in septic filter fields.

Septic System Site Characterization and Design -- 9 papers, including a pressure system design spreadsheet; problems associated with disturbed soils; man-made materials used to produce high-quality effluent; and an empirical procedure for analysis of mounding in the vadose zone in the evaluation of the viability of large septic systems.

Alternative Systems and Component Design -- 9 papers, summary of a study to determine the suitability of used tires as a substitute for drainfield aggregate in standard sewage disposal systems; field performance of chamber leaching systems ; alternative design for wastewater treatment