NR 503.10(3)(e)8.8. The landfill shall be designed with a system which allows gas venting from the entire landfill surface unless the landfill will utilize an active gas recovery system. An analysis shall be performed to determine the spacing needed between gas venting trenches for an effective system. The system shall be designed with a continuous layer below the capping layer which allows surficial venting from the waste final surface. This layer may be part of the grading layer required in subd. 1. if the specifications in this subdivision are met. This layer shall consist of a minimum of one foot of granular soil with a minimum hydraulic conductivity of 1x10-3 cm/sec, a series of flexible, perforated pipes connected to a series of outlets. A minimum of one gas monitoring well shall be located on each side of the landfill. The wells shall be constructed in accordance with s. NR 507.11. NR 503.10(3)(f)(f) All landfills regulated under this section shall be designed with storm water drainage ditches, structures and sedimentation basins designed to control rainfall runoff and limit entrained sediment from reaching surface water bodies. At a minimum, the storm water control system shall comply the following: NR 503.10(3)(f)1.1. All landfills shall incorporate the following concepts in the design of both temporary and permanent erosion and sediment control measures: NR 503.10(3)(f)1.d.d. Runoff shall be diverted away from disturbed areas and active fill areas. NR 503.10(3)(f)1.f.f. Drainageways and outlets shall be prepared to handle concentrated or increased runoff. NR 503.10(3)(f)2.2. Storm water drainage ditches, structures and sedimentation basins shall be designed to be constructed during the initial stages of construction. NR 503.10(3)(f)3.3. All temporary and permanent storm water drainage ditches, swales, conveyance channels, channel linings, outlet protections, culverts and other storm water control structures shall be designed using a 25 year, time of concentration storm event to determine peak flow rates. The design calculations shall each be performed for the period in the landfill’s development where the combination of surface conditions and contributing acreage would result in the greatest runoff volume. NR 503.10(3)(f)4.4. Temporary and permanent sediment control measures shall be designed to settle 0.015 mm size particles for all storms up to and including the 25 year, 6-hour storm event. The surface area for sediment basins shall be calculated using the average rainfall intensity over the 25 year, 6-hour storm event for the landfill. Principal spillway, emergency spillway and outlet protection for sediment basins shall be designed to pass a 25 year, time of concentration storm event. Emergency spillways for sedimentation basins shall be designed to pass a 100 year, time of concentration storm event. The design of the dewatering structures for sediment basins shall be selected such that the basin is dewatered in no less than 3 days. An analysis shall be performed to document compliance with this requirement. The design calculations shall be performed for the period in the landfill’s development where the combination of surface conditions and contributing acreage would result in the greatest runoff volume. NR 503.10(3)(f)5.5. Storm water shall be diverted away from the active fill area of the landfill and any borrow areas to a sedimentation control structure. The design calculations shall be performed for the period in the landfill’s development where the combination of surface conditions and contributing acreage would result in the greatest runoff volume. NR 503.10(3)(f)6.6. Containment berms placed around active fill areas shall be designed to control and collect the liquid volume resulting from the 25 year, 24-hour storm event. The design shall consider the volume of liquid generated from active fill areas which shall include areas with exposed solid waste or areas with waste covered by daily cover. Storm water in contact with active fill areas shall be handled and treated as leachate in accordance with ch. NR 506. NR 503.10(3)(f)7.7. Storm water drainage ditches, structures and sedimentation basins shall discharge along existing drainage patterns capable of accepting the anticipated flow volume. An analysis shall be performed to determine the amount and velocity of runoff prior to landfill development and to document compliance with this requirement. NR 503.10(3)(f)8.8. Storm water diversion and construction at a landfill shall be designed to minimize impacts on adjacent property, such as erosion, sedimentation and flooding. NR 503.10 NoteNote: Design of storm water management features shall include consideration of other applicable requirements of the department. Requirements include, but are not limited to, ch. NR 103, and permits required by ch. 30, Stats. NR 503.10(3)(g)(g) All landfills regulated under this section shall be designed with an inspection pad and storage areas for salvageable material as follows: NR 503.10(3)(g)1.1. The inspection pad shall be located outside of the landfill’s lined area. It shall consist of a permanent, all weather surface which is not readily permeable. The surface of the pad shall be concrete, asphalt or an alternative material approved by the department. NR 503.10(3)(g)2.2. The pad shall be designed to be of sufficient size to allow dumping of waste material directly from waste hauling vehicles and prevent delaying subsequent trucks waiting to dump loads. NR 503.10(3)(g)3.3. Storage areas for salvageable material shall be designed adjacent to or in close proximity to the inspection pad. At a minimum, storage areas shall be designated for clean soil, broken concrete and pavement, and clean wood. NR 503.10(3)(g)4.4. The department may require the construction of storage pads and storm water control structures for the salvageable material storage areas. NR 503.10(3)(h)(h) All landfills regulated under this section shall be designed to meet the following requirements: NR 503.10(3)(h)1.1. A method of controlling any dust or windblown debris shall be included in the landfill design. The factors which will be considered by the department when evaluating alternative provisions for controlling dust and windblown debris include the remoteness of the landfill, natural screening, windbreaks and waste types. NR 503.10(3)(h)2.2. All access roads which are used by over the highway vehicles shall be designed with a maximum grade no greater than 10%. The intersection of the landfill access road with an existing highway shall be designed to provide sufficient sight distance and minimum interference with traffic on the highway. NR 503.10(3)(h)3.3. The landfill shall be designed so that final grades in each phase are reached as soon as possible, and the open area used for waste filling is minimized. NR 503.10(3)(h)4.4. The final slopes shall be equal to or greater than 5%, but may not exceed 25%.