Casino Storm Water Impacts

Exhibit D-4 Storm water Improvements.   
 The proposed improvements in this section are boiler plate statements that refer to ”Detailed storm water calculations will be provided during the Milford Conservation Commission and Planning Board reviews and approvals.”  Basically this means that they know what they are required to do, but they don’t know how they are going to do it yet. These proposed controls and designs will also be subject to state and federal approvals as well. 
    These studies are different than traffic and water use studies in that, simply, those studies rely on estimated future potential impacts, using generalized, accepted standards.  Storm water impact review requires detailed site information and detailed final site designs for evaluation. These probably have not been done yet for the Casino….. I would be surprised if they were. 
   The design of storm water management of this site will be very challenging. Bedrock ranges from exposed outcrops to an average of 2.5 feet below grade, according to Town Soil Survey. The Draft Plans indicate proposed infiltrative BMP’s, (designed areas where the water will infiltrate into the soil) ranging from 3-4 feet in depth.   
  There is a reason that there is a business removing stone and gravel near the location of the proposed Rte. 16 access road…..There is rock at or near the surface….Have you looked at our quarries?   Once you get below a shallow soil layer, the granite layer is very deep and very solid.    Infiltration does not very well in rock.   
   Town Consultant comments indicate that some proposed storm water controls could be closer than 10 feet to wetlands. Some larger basins “may yield further additional encroachment.”  Acceptable protective encroachments to wetlands range closer to 100 feet and not less than 10 feet.     As stated in the Town’s consultant, Beals and Thomas, Inc. report…”Given the limited space allotted between the site work and the wetlands, it may be challenging for the Proponent to meet the criteria of the CGP” (EPA 2012 Construction General Permit).
     The Milford Conservation Commission has the ultimate authority to approve such close encroachments to the Town’s wetlands and should ensure that these encroachments will not severely impact these wetlands and the state designated vernal pools. The critical habitat area of vernal pools includes the upland habitat area surrounding the pool itself. Impacts to these areas will be subject to review of local, state ,and federal agencies.     Storm water management could provide a greater challenge to the project than anticipated…