(2) If the commission finds a threat to drinking water exists within the territory and the conditions could be removed or alleviated by the construction of treatment works, the commission shall order the governing body to proceed with construction of the treatment works.

(3) If the commission finds that a threat to drinking water exists in only part of the affected area or that treatment works would remove or alleviate the conditions in only part of the affected area, the commission may reduce the affected area to the size in which the threat to drinking water could be removed or alleviated. The findings shall describe the boundaries of the affected area as reduced by the commission.

(4) In determining whether to exclude any area, the commission must consider whether or not exclusion would unduly interfere with the removal or alleviation of the threat to drinking water and whether the exclusion would result in an illogical boundary for the provision of services.

(5) If the commission determines that a threat to drinking water exists but that the proposed treatment works are not the most economical method of removing or alleviating the conditions, the commission may issue an order terminating the proceedings under ORS 454.275 to 454.380, or referring the resolution or ordinance to the municipality to prepare alternative plans, specifications and financing methods.

(6) At the request of the commission the municipality or a boundary commission shall aid in determining the findings made under subsections (3) and (4) of this section.

(7) The commission shall file its findings and order with the governing body of the municipality. [1981 c.358 §7]