|
PPSSD PUBLIC HEARING The meeting was opened by Chairman
Nevalainen at The purpose of the addendum is to
provide an update to the treatment system with respect to the Minnesota Pollution
Control Agency nitrogen policy and treatment system suitability and to further
evaluate an alternative for seasonal woodland irrigation. The addendum includes these updates to the Design
Basis Update; In section 4.3
wastewater design loadings of the Nitrogen Removal Component; The MPCA has a Large Subsurface Treatment System (LSTS) ground water nitrate nitrogen policy. This policy requires every new LSTS to achieve a 10 milligram per liter or less nitrate nitrogen concentration in ground water at the property boundary or nearest receptor. The policy includes two permitting options. Option No. 1 requires an abridged hydrogeologic assessment.. Option No. 2 requires a complete hydrogeologic assessment and a ground water monitoring well network The project has a projected design
flow that is above 10,000 gpd and therefore the system is classified as an
LSTS. AS an LSTS, the treatment system
will need to be designed to meet the MPCA nitrate nitrogen removal policy. The Treatment System Suitability; because of the reliability of the aerobic treatment units to provide treatment throughout the year, the aerobic treatment unit is recommended over the constructed wetland. Seasonal Woodland Irrigation; the use of a woodland irrigation system during summer would preclude the system from falling under the design requirements of an LSTS. However, nitrogen treatment would be addressed in the design as well as the requirements for disinfection. The woodland irrigation system would be designed to minimize environmental disturbance. Recommendations; The recommended system includes a STEP collection, aerobic treatment, seasonal woodland irrigation with offseason infiltration beds. Comment Period: Questions asked were about the timeline for the work to be done and cost. Brett Balavance commented on the permitting process. EDU versus monitoring of business parcels. Mr. Balavance stated that Debt service and operating and maintenance stated individually on a statement works very well. Respectfully Submitted, Mary Manninen, Clerk See attached attendance list |