(1) In developing on-site program management plans required under RCW 70A.110.030, the local health officer shall propose a marine recovery area for those land areas where existing on-site sewage disposal systems are a significant factor contributing to concerns associated with:

(a) Shellfish growing areas that have been threatened or downgraded by the department under chapter 69.30 RCW;

(b) Marine waters that are listed by the department of ecology under section 303(d) of the federal clean water act (33 U.S.C. Sec. 1251 et seq.) for low-dissolved oxygen or fecal coliform; or

(c) Marine waters where nitrogen has been identified as a contaminant of concern by the local health officer.

(2) In determining the boundaries for a marine recovery area, the local health officer shall assess and include those land areas where existing on-site sewage disposal systems may affect water quality in the marine recovery area.

(3) Determinations made by the local health officer under this section, including identification of nitrogen as a contaminant of concern, will be based on published guidance developed by the department. The guidance must be designed to ensure the proper use of available scientific and technical data. The health officer shall document the basis for these determinations when plans are submitted to the department.

(4) After July 1, 2007, the local health officer may designate additional marine recovery areas meeting the criteria of this section, according to new information. Where the department recommends the designation of a marine recovery area or expansion of a designated marine recovery area, the local health officer shall notify the department of its decision concerning the recommendation within ninety days of receipt of the recommendation.