§ 171.101 PERFORMANCE OBJECTIVES FOR SOIL BASED ONSITE WASTEWATER TREATMENT SYSTEMS.

   (A)   Performance objectives. Soil based onsite wastewater treatment systems shall meet the performance objectives described in this section, as the objectives apply to the system type, and shall perform so as not to create an imminent health hazard or a public nuisance.

      (1)   Long term wastewater treatment and infiltration. Proposed soil based onsite wastewater treatment systems shall be designed to best facilitate the long term treatment and infiltration of wastewater employing the most appropriate soil and linear loading rates taking into consideration vertical and horizontal water movement through the soil, and application methods.

      (2)   System capacity. Proposed soil based onsite wastewater treatment systems shall be designed to be of adequate capacity to treat and infiltrate the projected daily wastewater flow.

      (3)   Wastewater treatment. Proposed soil based onsite wastewater treatment systems shall be designed to treat wastewater to the following standards prior to the wastewater coming into contact with a limiting layer: BOD5 and TSS < 10 mg/l; and Fecal Coliform < 3,000 cfu/100 ml. It is recognized that septic tank effluent, solely or comingled with exterior grease interceptor effluent, subjected to the following treatment processes shall meet or exceed the treatment standards specified in this section:

         (a)   Unsaturated flow through at least 24 inches of year-round unsaturated soil, as determined in accordance with the requirements of §§ 171.085 through 171.089.

         (b)   Unsaturated flow through at least 16 inches of year-round unsaturated soil, as determined in accordance with the requirements of §§ 171.085 through 171.089 and after receiving treatment by a pretreatment component certified by an ANSI accredited third party testing and certification organization to meet NSF ANSI Standard Number 40, maintained as follows:

            1.   Service, inspection and necessary maintenance shall be performed in accordance with the requirements of §§ 171.220 through 171.224 by a service provider licensed in accordance with the requirements of § 171.184.

         (c)   Unsaturated flow through at least 12 inches of year round-unsaturated soil, as determined in accordance with the requirements of §§ 171.085 through 171.089 and after receiving treatment by a pretreatment component certified by an ANSI accredited third party testing and certification organization to meet NSF ANSI Standard Number 350, maintained as follows:

            1.   Service, inspection and necessary maintenance shall be performed in accordance with the requirements of §§ 171.220 through 171.224 by a service provider licensed in accordance with the requirements of § 171.184.

(Ord. [Bd of Health Ord., Art. V], passed 11-12-1996; Ord. [Bd of Health Ord., Art. V], passed 11-12-2013; Ord. 17-0605, passed 6-13-2017)