Maryland Code, Environment § 4-413

(a) Except as provided in subsection (b) of this section, or except as authorized by a permit issued under § 9-323 of this article, it is unlawful for any person to add, introduce, leak, spill, or otherwise emit soil or sediment into waters of the State or to place soil or sediment in a condition or location where it is likely to be washed into waters of the State by runoff of precipitation or by any other flowing waters.

(b) A person engaged in agricultural land management practices, as defined by the Department for the purposes of Subtitle 1 of this title, may not add, introduce, leak, spill, or otherwise emit soil or sediment into waters of the State unless that person is implementing and maintaining a soil conservation and water quality plan approved by the local soil conservation district. If a person engaging in agricultural land management practices without a district approved soil conservation and water quality plan complies with an order for corrective action issued under § 4-412(a) of this subtitle, that person shall not be subject to penalties as provided under § 4-417 of this subtitle.

(c) With the approval of the Department of Agriculture, the Department of the Environment shall adopt regulations to implement subsection (b) of this section.