Which of the following is not considered a standard disposal system?

A gravelless pipe system is considered a proprietary technology, which means it is a specific design or brand that may not universally meet all standard disposal criteria. In contrast, conventional septic systems, drip irrigation systems, and absorption trenches are widely recognized and accepted standard practices for the disposal of effluent in on-site sewage facilities.

Conventional septic systems consist of a septic tank and a drain field, both of which are traditional and well-regulated methods for treating household sewage. Drip irrigation systems use low-pressure tubing to evenly distribute treated effluent into the soil, designed for more efficient absorption and nutrient distribution. Absorption trenches are a method of dispersing effluent over a wider area, promoting proper filtration and absorption into the soil. All of these methods are established practices in the field of on-site sewage management, while gravelless pipe systems represent an innovative approach that may not yet be classified as standard.