1601 FLORIDA DR Geotech Report 2022-10-25

February 13,2018 Page 3 of 3 Stormwater Management Recommendations We recommend placement of Tensar TX5 geogrid over the resulting subgrade prior to rock placement. Geogrid should be placed on level ground and clean angular rock may be used to fill in any voids that result from root removal. For this site,we understand that the proposed pavement section consists of 4 inches of permeable asphalt over 2 inches of 5/8" clean angular rock (grading course) placed over 6 inches of 1-1/2" clean angular rock (base course). We recommend placing an additional 3 inches of base course below the overall section for stability purposes. We understand that an drain system will be installed within the base course rock near Florida Drive to remove excess runoff when necessary. We analyzed two soil samples of the near surface native soils for organic content and Cation Exchange Capacity. The results of these analyses are as follows: Test/Sample Organic Cation Exploration Elevation Content Exchange Soil Classification NumberCapacity USCS) (Feet Below (USDA/ Grade) HB-2 2 5.5% 8.7 meq Loamy Sand/SM HB-4 2 6.1% 9.2 meq Loamy Sand/SM The near surface soils are suitable to provide water quality treatment of the anticipated runoff. We recommend keeping all construction traffic off of any pervious concrete or asphalt once it has been placed. It is important to keep heavy loads and any silt/dust from the new concrete/asphalt. Closure The information presented herein is based upon professional interpretation utilizing standard practices and a degree of conservatism deemed proper for this project. We emphasize that this report is valid for this project as outlined above and for the current site conditions,and should not be used for any other site. Sincerely, Cobalt Geosciences,LLC "4, 3,i C , I 1 1a f HABERMAtfl Phil Haberman,PE,LG,LEG Principal