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Standards for culvert installation. Design will safely convey a Qzs storm event across the Access Road. ITEM NO. 8 RESPONSE: Refer to Item No. 7 Response above in part for the response to this comment. The typical section was Intended to ' demonstrate general conditions and minimum criteria. Culverts will each require site specific design as previously indicated and the design and construction criteria will be CDOH Standards for a Qzn storm event. ' Profiles will be generated to identify all pertinent design fe::lures including HW/D and cover. ' The subsurface soil conditions will to some extent dictate the rross- section. In the case of 30"-36" pipes the bottom oP pipe may be into existing sandstone making excavation extremely difficult. If this condition is encountered, an alternate equivalent design of a pipe arch section or t twin culverts may be necessary. The Operator commits to install six (s) culvert crossings in locations shown on the CAP. The installations grill be in accordance with the Preliminary Designs to CDOH Standard, and ' adequate to convey a Qze storm event. ITEM NO. 9 RESPONSE: Each culvert Installation exceeding 100 feet in length will include an adequate number oP anti seep collars to result In an ' equivalent flow path length oP 1.2 times the total culvert length. The collars will be identified on the culvert cross-sections and inspected during construction. '' Preliminary design Indicates only culvert HR-3 will require a:t anti seep collar. The Operator commits to installation of all required anti-seep collars. ' ITEM NO. 10 &, 11 RESPONSE: The drainage system below Culvert HR-6 was initially identified in the Cedar Heights Drainage' Master Plan. 1~he proposed 24" CMP under Cedar Heights Drive East (the receiving culvert for HR-6 proposed) was originally designed to be installed at the natural drainage crossing. It is obvious from a field inspection that the culvert, as installed, functions with a definite purpose: that of low point drainage ' in Cedar Heights Drive. It was likely installed as a roadway draiinage facility, not across-culvert. Apparently the low point system was also intended to accommodate the natural runoff which would travel some 400 ' feet In Cedar Heights Drive. There has not been a significant flow <<t this point to date because HR-6 doesn't exist. Flows are currently being intercepted by the Quarry Access Road and carried to the exlstliig 54" ' culvert. -- Installation of the HR-6 facility will Impact Cedar Heights Road by outfalling runoff onto the roadway and this condition is not currently ' occurring. Installation of a culvert larger than 24" will allow runoff in excess of the capacity of the existing system to enter the roadway. This will likely cause flooding and possible roadway overtopping and ero:~lon in ' the area oP the low point. ~'he Operator will commit to installing only a Ll 24" culvert at HR-6 unless all parties of Interest relieve the Operator of 4 1