These exemptions do not mean that a permit is not required for the specific activity if required by other federal, state, County or local law, ordinance, rule or regulation. The following categories of development are exempted from the requirements of providing a stormwater management plan:
A. 
Agricultural land management practices.
B. 
All new development on sites where no previous development has occurred conducting a land disturbing activity of no more than 5,000 square feet (0.1148 acre) which are not located within the Buffer Area of the County's Critical Area Overlay Zones as established in the Charles County Zoning Ordinance[1] shall be exempt from providing stormwater management. Any cumulative disturbance exceeding 5,000 square feet shall not be exempt. If the initial disturbance occurred prior to 1985, then stormwater management shall only be provided for a new development. If the initial disturbance of the site occurred after 1985 and the site qualified for an exemption for disturbance of less than 5,000 square feet, then stormwater management shall be provided for the entire disturbance (initial and proposed) once the disturbance on the site exceeds 5,000 square feet.
[1]
Editor's Note: See Ch. 297, Zoning Regulations.
C. 
Additions or modifications to existing single-family detached residential structures that do not disturb more than 5,000 square feet of land area.
D. 
Land disturbance activities or developments which the Administration determines will be regulated under specific state laws that provide for the management of stormwater runoff.