7 Del. Admin. Code § 7103-13.0

Current through Register Vol. 28, No. 4, October 1, 2024

Section 7103-13.0 - General Design Principles

13.1 The wastewater must be characterized, and the available land must be evaluated to calculate the allowable loading rate of each constituent in the waste, including the hydraulic loading. For certain heavy metals, the loading rate is determined from maximum allowable accumulative applications for a chosen life expectancy over which the system should operate without any irreversible degradation of the soil for agricultural purposes. From the calculated loading rates, the limiting constituent (the one requiring the most land) is determined.

13.2 As this point, pretreatment options can be considered to reduce the amount of land required. Management of the land treatment system must also be considered in setting loading rates and application limitations. Management of vegetation and sale or disposal of crops or trees must be considered. Application equipment must be chosen appropriate for the site, application rate and overall system operation, including crop or forest management. Storage should also be designed to provide safe retention during periods when application may not be possible.

13.3 The design should also preclude runoff of wastewater during application, minimize surface runoff transport from the site, preclude extended ponding, allow for appropriate buffer zones at the site perimeter, and allow for operation during freezing weather (unless it is opted to store wastewater during winter months), and include alarms and safety features that prevent over application and system failure. Also, odors must be controlled. Good standard operating procedures and monitoring plans should be designed to insure safety of workers and prevent environmental degradation of soil and water resources.

7 Del. Admin. Code § 7103-13.0