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11 10 years, and 100-year storm event, provide water quality mitigation, and ground water recharge requirements. Hence the need for the additional storm water system. • Additionally, the applicant is proposing to demolish and replace the exiting asphalt driveway with pervious pavers. • The void space of the subsurface stone provides additional storm water storage capacity. • The applicant is also proposing to construct a scour hole at the terminus of the 36-inch covert in the south east corner of the site along with the outlet control structure on the pipe. • There is also a 2-foot-wide curtain drain proposed at the perimeter of the flatter lawn area to promote infiltration. • The calculations for the sizing of the scour hole including the outflow from the dry well system shall be added to the report as requested by Matrix in their January 8th review letter. • Together the measures bring the site into compliance with the required storm water regulations. • As the driveway is reducing the motor vehicle surface and providing porous pavement and a slight reduction from the existing configuration, the water quality requirement is met. • Through proposed infiltration practices, the site is designed to maintain 100% of the average annual ground water recharge vine. • As can be seen on page 3 of the Storm Water Report, the proposed practices are designed to meet and/or exceed the required peak runoff reduction for the 2, 10, and 100-year storm events. • The storm water report includes the modeling and mapping used to calculate and demonstrate the compliance as just outlined. • Matrix’s January 8th letter includes some minor technical comments about the drainage report which they can state they have no issue in addressing as a conditional approval should the board sees fit. • Soil movement calculations shall be added to the plans and a permit shall be sought from HEPSCD. • They do not intend to remove any additional trees. • The plans also propose the construction of a tier boulder wall in the rear of the property. • On page 3, the layout plan, you can see the grayer wall is under construction, that is the wall as it is today. They are proposing to add a second wall stepped back hence the term tier to reduce the overall height of the wall. • On page 4, the grading plans, identified at the north end, the wall is non-existent, not even a foot high and as it progresses

pped back hence the term tier to reduce the overall height of the wall. • On page 4, the grading plans, identified at the north end, the wall is non-existent, not even a foot high and as it progresses south, the wall gets to a height of about 2 ½ feet and that will be the height of the existing wall and then there shall be a little bit of grading in between to the next wall which will also have a maximum height of 2 ½ feet at its highest point. • The distance between the two proposed tiers is about 4 to 5 feet. • Mr. Cokeley’s office can supply the requested details and supported calculations from a licensed structural PE requested by Matrix as a condition of final approval should the board sees fit. • On page 2, the existing condition of the driveway has a little bit of inconsistent edge on some spots and flares out whereas on page 3, you can see it is a smoother curve and that allows for a reduction on the pervious surface overall. • Once the system is approved by the board, then they will generate the storm water