In addition to the evaluation of the shellfish growing waters, and before establishing a classification for the beach, the department shall conduct a sanitary survey of the shoreline and upland areas located adjacent to recreational shellfish beaches. The sanitary survey shall be updated as necessary to reflect changes in shoreline and upland sanitary conditions. A sanitary survey shall consist of:

(1) Identifying and evaluating point source discharges in the vicinity of the beach;

(2) Evaluating all on-site sewage disposal systems in the survey area; and

(3) Evaluating impacts from other nonpoint sources in the area, such as animal waste and stormwater.