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RCA Exhibit A 15� emergency vehicle access. Ms. Romanowski suggested that Mr. Mueller keep his existing beautiful home 15 � and build one additional home on the extra lot, similar to that done by others in that neighborhood. 15�: Engineer Chuck Plowe 15� Regarding concerns raised during public comment about the level of groundwater in basins, Mr. Plowe 15� reported that soil boring information indicated to engineers designing them, that their design should be 3' 155 or more below water basins for infiltration and for the drain tiles to function properly. Mr. Plowe noted that 156 all of these designs would require review and approval by the City Engineer as well as engineers with the 15r Watershed District. Regarding those levels, Mr. Plowe advised that they were typical for down water 158 streams, with water infiltrating and percolating onto adjacent properties with tight soils, thus the reason for 15� drain tiles without the advantage of sandy soils, negating the need for the drain tile system. Mr. Plowe 16C clarified that engineered soil materials would be installed above those drain tiles with the intent to make 16` the water drain down into that system. �6�: In response to Mr. Ramalingam's questions related to the ponds, and whether they would be dry before 16i the next rainfall event begins, Mr. Plowe responded that typically they would be as the soil media and 16� drain tile draws that water level down over a 48-72 hour period; but again noted the City Engineer and 165 Watershed District engineers would also review and ultimately approve the stormwater management 166 plan. 167 Specific to groundwater levels, Member Murphy sought clarification that in order for this design as 168 proposed to pass muster, it needed to be at least 3' less than the number needed; with Engineer Plowe 169 responding affirmatively. 17o Specific to the removal of trees and impacts to the soil evaporation rate, Member Murphy asked Mr. 171 Plowe if that was a common consideration in site drainage plans. 17% Mr. Plowe advised that it was, and in developing the whole design, both existing condition calculations 173 and redesigned or proposed calculations were taken into consideration, including taking into account 17� added impervious surfaces and how much additional runoff would occur and not be infiltrated; providing 175 the overall system design. 176 At the request of Member Murphy, Mr. Plowe stated that removal of trees for grading and other 17i redevelopment needs could not be specifically calculated at this time, but evaporation and runoff is taken 178 into account. 17� Chair Boguszewski asked if Mr. Plowe was confident that the 8" drain on Acorn Road would suffice. 180 Mr. Plowe responded that he was confident; and when reviewing the basins and infrastructure, there 18� would continue to be some overflow as there is today, but the intent was not to have a lot of flow go 18� through the 8" infrastructure system, but available to handle a 2-year rain event. Mr. Plowe opined that 18:� the system would prove adequate for short-term ponding and with smaller storm events that would not be 1 s� much water for any length of time, but that it was taken into consideration in designing the stormwater 1 s5 management system. 186 As noted in the staff report, and confirmed by Mr. Plowe, Member Murphy stated that the City Engineer's 187 review of the plan and his input indicated the new pipe would still be accommodated by the existing 188 downstream system on Acorn Road; with a minimal amount of additional water added to that storm sewer 189 system and not creating any additional problem. 19C� Chair Boguszewski closed the public hearing at 7:15 p.m.; no one else spoke. 191 Member Cunningham noted that she had supported the last four proposals, and opined that this latest 192 proposal from the applicant provided even more significant improvements and commended Mr. Mueller 193 for listening to his neighbors and addressing their concerns. Member Cunningham stated her main � 9� concern in the past was with the road width and tree issues, as well as significant drainage issues; but 195 again noted Mr. Mueller appeared to have addressed those concerns and improved upon them. 196 Therefore, Member Cunningham stated she would be hard pressed not to support this request. 197 MOTION 198 Member Murphy moved, seconded by Member Cunningham to recommend to the City Council 1�9 approval of the proposed PRELIMINARY PLAT of the property at 2201 Road; as detailed and Page 13 of 15