A. Slope Restriction. No area which exceeds the maximum allowable slope per Table I, shall be included in the ½ acre of suitable soils or the designated septic system and future replacement areas.
B. Required Setbacks. The ½ acre of non-critical soils and the designated septic system and future replacement areas shall be exclusive of all areas which fall within the setback distances listed in Table IV.
C. Stormwater Drywells. There shall be a 200 foot well restriction from all existing and proposed stormwater drywells (Class V injection wells) shown on the tentative and final plats.
D. Small Lot Size. Where ½ acre and smaller lot size dictates, designated locations of wells and septic systems shall be shown on the lots (on the final plat) to eliminate future conflicts between wells and septic systems.
E. Easements. The ½ acre of non-critical soils, and areas designated for private sewage disposal systems and replacement septic systems, are exclusive of all easements (i.e. drainage, road construction, utility, landscape, etc.).
F. Flood Hazard. Land designated as Flood Hazard is not acceptable for the installation of a septic system and cannot be included as part of the ½ acre of non-critical soils, or the designated septic system and future replacement areas. All areas within the subdivision which are located within the Flood Hazard area shall be designated on the final plat.
G. Dimensions. All dimensions, linear, curvilinear, and angular, necessary to properly re-survey, shall be shown, with linear dimensions in feet and decimals of a foot.
H. Scale Of Plats. Tentative and Final Plats shall be drawn at a scale of 1 inch to 100 feet or larger.
I. Community Sewer And Water. Documentation shall be provided to the Department that community water and sewer are not available and accessible to the property.
J. Cutting/Filling Of Soils. All areas of filling and/or cutting must be clearly delineated on an engineering plan. It should be known that this may influence septic suitability and additional soil work may be required.
K. The use of fill and/or cutting of soils is strongly discouraged and usually results in at least as critical if not more critical soil limitations for onsite domestic wastewater systems. The primary controlling factor to be considered is that the natural soils must be unencumbered by a limiting layer within 30 inches of the natural soil surface. Fill can only be used if that criterion is met. In this event, fill would have to be limited to carefully controlled situations, accompanied by detailed engineering. The lower portion, if not all of the sewage disposal system, must be a minimum of six inches into natural (undisturbed), uncompacted soils and no deeper than thirty-six (36) inches from a final grade. At the time, the separation below the trench bottom to the top of the limiting layer shall be maintained as required in Table I.
L. Made Land. Removal of native soils and replacement with suitable soils shall be considered a “made land” situation, and is not usually acceptable for on-site, domestic wastewater disposal purposes. Any such consideration of this approach should be only after consultation with Department personnel prior to preparing any plans. In addition to the normal soils evaluation in areas of made lands, the following factors will also influence soil suitability: length of time fill has been in place; degree of compaction; stratification of soil texture; re-establishment of soil structure and depth; predictable extent of materials; and integrity of the fill/natural soil interface.
M. Artificial Drains. Use of artificial drains to lower seasonal high groundwater tables shall be in compliance with § 8.04.430 F.
N. Hydrogeological Assessment. The proposal shall comply with § 8.04.610 of this Ordinance. When rapid or very rapid permeable soils are present in the top thirty six (36) inches of a proposed subdivision utilizing subsurface domestic wastewater disposal, a hydrogeological investigation report will be required. This report shall be completed by a licensed professional geologist and contain, at a minimum, the following information:
1. An evaluation as to the availability of sufficient quantity of water to serve the proposed subdivision; and
2. Shallow groundwater depth(s) and flow direction(s) at the proposed subdivision.
3. An evaluation of upgradient negative groundwater influences on the proposed subdivision. Potential influences for consideration shall include but not be limited to known groundwater contamination sites and upgradient land uses which may impact groundwater quality;
4. An evaluation of downgradient negative groundwater influences by the proposed subdivision. The cumulative impact of chlorides, nitrates, phosphates and bacteria on groundwater, and any downgradient sensitive environments (i.e. surface water, wetlands, fens, etc.) shall be evaluated at a minimum, and
5. Recommended actions to minimize impact of upgradient groundwater on the subdivision or the subdivision's impact on downgradient groundwater.
(Ord. O-201711-51-031, passed 11-14-2017)