12VAC5-610-470. Physical features.
A. Physical features including soil features, slope, depth of rock, the location of rock outcrops, drainage ways, marshes, swamps, sink holes, flood plains, artificial drainage systems, and various structures and topographic features found in Tables 4.1 through 4.4 shall be fully and accurately documented in writing as part of the site and soil evaluation.
B. Drainage way. A drainage way is a concave portion of the landscape in which surface water or rain water run-off gathers intermittently to flow to a lower elevation.
C. Fill material. Fill material means soil transported and deposited by man as well as soil recently transported and deposited by natural erosion forces. Recent natural soil transportation and deposit is evidenced by one or more of the following.
1. No or indistinct soil horizons;
2. Depositional stratification;
3. Presence of a buried organic layer; and
4. Position in the landscape.
D. Minimum depth to seasonal water table. As used herein, "seasonal water table" means that portion of the soil profile where a color change has occurred in the soil as a result of saturated soil conditions or where soil concretions have formed. Typical colors are gray mottlings, solid gray or black. The depth in the soil at which these conditions first occur is termed "seasonal water table."
E. Artificial drainage. Where soils are artificially drained, soil coloration may no longer be an accurate indicator of the position of the seasonal water table. Three types of artificial drainage systems which are generally considered are as follows:
1. A water table depressor system of buried conduits, i.e., agricultural drainage tile;
2. A lateral ground water movement interceptor is a buried conduit for the purpose of intercepting lateral ground water movement, i.e., a French drain; and
3. Open ditches with the bottom elevation of the ditch below the seasonal water table.
Statutory Authority
§§ 32.1-12 and 32.1-164 of the Code of Virginia.
Historical Notes
Derived from VR355-34-02 § 3.3, eff. February 5, 1986; amended, eff. May 11, 1988; Virginia Register Volume 16, Issue 16, eff. July 1, 2000.