Land Application: an alternative to discharge
The Kilmer’s Point and Cedar Point subdivisions have been using land applications via a spray irrigation system for over a decade. It is a viable alternative to discharging effluent into rivers and creeks. The following are DEQ’s requirements for that system, which is permitted to treat up to 32,500 gallons per day. Middlesex County is seeking a permit for 39,900 GPD.
- The design flow of the facility is 32,500 gallons per day and receives wastewater from both the Kilmer’s Point Subdivision and Cedar Point Subdivision.
- The design consists of two aerated lagoons for the primary & secondary treatment, and a third lagoon that serves as a polishing pond. The treated wastewater flows from the polishing pond to the chlorine contact tank where it is disinfected. From there, it is pumped to a 14 acre field via a diesel-powered pump and applied to the land with a “rolling spray nozzle”.
- The application rates cannot exceed the following: 0.25 inches per hour, 1 inch per day, or two inches per week.
- The wastewater itself is tested daily and monthly for 7 parameters.
- Since groundwater contamination is a potential problem with spray irrigation systems, there are four groundwater monitoring wells onsite which must be tested on a once per three month basis. There are 7 different parameters that are tested.
- The soils within the spray field are tested on a once per six month basis for 18 different parameters.
- The facility must have a Class IV operator (same requirement as the proposed Middlesex Courthouse Treatment Plant).
- There are buffer distances that must be kept from drinking water wells, occupied dwellings, improved roadways, surface water drainage patterns, property lines, and from agricultural drainage ditches that are built to keep groundwater tables down (like the ones you see through the middle of the fields in Mathews County).
- The vegetation that currently grows within the field must be maintained, which means cutting it seasonally.
- Wastewater cannot be applied during periods of wet weather or on frozen ground.
Download Middlesex County’s application for a waste water treatment plant that will discharge into an unnamed tributary of Urbanna Creek. Just click here.