Maryland Code, Environment § 9-331

(1) To keep records;

(2) To make reports;

(3) To install, calibrate, use, and maintain monitoring equipment or methods, including, where appropriate, biological monitoring methods;

(4) To sample discharges in accordance with the methods, at the locations, at the intervals, and in the manner the Department requires; and

(5) To provide to the Department any information that the Department reasonably requires about: