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Comments: 1. Overall Capacity.The wastewater system is of conventional design for a limited wastewater flow,based on a fixed number of toilets, urinals and sinks (32)and the assumption of each toilet/urinal being used once per hour,ten hours per day. Based on a typical average of three restroom uses per worker per workday,this would equate to a workforce of approximately 100 people in Buildings A&B combined. While the buildings may be used and operated with this number of employees, the overall size of the buildings would allow a much greater occupancy. Under greater(allowable) occupancy wastewater generation volumes could easily increase beyond the capacity provided in the proposed wastewater facilities. In order to anticipate and provide appropriate adjustment for possible future increases in activities/occupancy, I recommend the following: a. Identify a contingency plan including additional area for future expansion of wastewater treatment and disposal facilities,demonstrating sufficient capacity to accommodate the maximum reasonable use/occupancy of the buildings. b. Implement an on-going monitoring program to measure and record actual wastewater flows on a monthly or quarterly basis for comparison with system design capacity and assumptions. The information would be used in the future to determine if and when measures should be taken to expand the wastewater system capacity. APPENDIX A—NITRATE LOADING STUDY(Chesney Consulting,dated May 6, 2019) The appended Nitrate Loading Study by Chesney Consulting utilizes an annual chemical-water mass balance analysis (per Hantzsche-Finnemore Equation)to estimate the nitrogen loading impact on groundwater from onsite disposal of wastewater from Buildings A&B. The analysis projects a resultant percolate concentration of 6.29 mg-N/L reaching the groundwater table,averaged over the 10-acre footprint of Buildings A&B. This is compared against the drinking water nitrate-nitrogen standard of 10 mg-N/L to conclude that the discharge is within appropriate limits and will not significantly degrade groundwater quality. Comments: 1. Methodology. The mass balance analysis per the Hantzsche-Finnemore Equation is a simplified method for assessing wastewater-nitrogen loading for typical rural residential properties served by septic systems. It doesn't explicitly account for large amounts of impervious surface, nor drainage retention facilities,as proposed for this proposed project. The improvement plans indicate nearly the entire site will be covered with buildings and paving, leaving very limited amount of open land area for deep percolation/recharge. The rainfall-runoff from impervious surfaces is planned to be collected and routed to an adjacent detention/retention basin for percolation and downstream discharge. The concept and principles of Hantzsche-Finnemore Equation are still valid, but a rearrangement of terms and 2