4.1 & 4.2 PCSR 01-14-2014 - Laserfiche WebLink

Home Browse Search

Based on a review of the information we have received thus far, a number of comments and questions have been generated. Please review and address: General Comments 1. As noted in the attached File Closure letter from the MPCA,the applicant shall notify the MPCA of the presence of petroleum odor which was encountered and noted in Soil Borings 4 and 5. The MPCA may require additional testing and remediation as part of redevelopment. Additional contamination may be present and an environmental construction contingency plan should be developed. 2. Locate the rooftop HVAC units on the plans and provide line of sight drawings to verify screening from the street. • 3. The landscape plan must be prepared by a registered landscape architect. Drainage Comments 4. Both existing and proposed stormwater models should be run using updated ATLAS 14 precipitation data. 5. 3-feet of separation between the seasonally high groundwater table and the bottom of an infiltration device is required. It appears from the site borings and plan details that the bottom of the infiltration rock storage will be less than 3-feet from groundwater.This should be revised as necessary. 6. The new MS4 permit requires redevelopments to maintain/reduce existing discharge quantities of runoff volume,Total Suspended Solids (TSS),and Total Phosphorus (TP) on an average annual basis. The State has developed policy for meeting this requirement one of two ways.Applicants can either show calculations showing the reduction of volume,TSS, and TP on an average annual basis or design the improvements to infiltrate of the first 1.1" of rainfall over the.new impervious. (This 1.1" amount is accepted as the standard required to meet the limits for pollutant loads thus not requiring the pollutant load calculations) 7. The calculation should be provided indicating the required infiltration volume is met by the proposed infiltration system. 8. The continuity error in the drainage calculation simulation should be corrected for Pond 3. 9. Consistent with new MPCA regulations,the applicant should develop and submit a written maintenance program describing the post construction stormwater maintenance operations to ensure the continued function of the infiltrating system as designed and expected. Sheet 2 of 12—SWPPP 10. Sweeping of adjacent public streets shall be accomplished with 1 hour notice of the engineer or regulating agency. Failure to meet this requirement may result in the work being done by the City and billed directly to the owner of the project. 11. Inspector Log/Maintenance section,second sentence. This should be reworded to include State and City right of way,not county. 2