Sec. 1. 12 MRSA §6001, sub-§34-B is enacted to read:

34-B.__Process water.__"Process water" means the water used in the depuration process.

Sec. 2. 12 MRSA §6856, sub-§9 is enacted to read:

9.__Chlorination or ultraviolet radiation.__If a shellfish growing area is closed to the taking, washing and possessing of shellfish due to runoff related to heavy rainfall pursuant to section 6172, subsection 2, a holder of a depuration certificate pursuant to subsection 3 that applies additional water purification treatment to process water through chlorination or ultraviolet radiation is exempt from the shellfish emergency rainfall closures provided the following conditions are met.

A.__If chlorination treatment is used:

(1)__Wash water must contain 0.1 parts per million of residual chlorine for at least one hour of contact time prior to use;

(2)__Treated process water may be used only for wash water; and

(3)__The holder of a depuration certificate pursuant to subsection 3 shall take samples of source water, chlorine-treated water and washed shellfish.__ Shellfish samples must be analyzed for fecal coliform and water samples must be analyzed for total coliform at a laboratory certified under the National Shellfish Sanitation Program.__The holder of a depuration certificate shall monitor chlorine and salinity levels in the treated process water.

B.__If ultraviolet radiation treatment is used:

(1)__Turbidity may not exceed 20 nephelometric units;

(2)__Turbidity must be measured using a method endorsed by a national organization of public health professionals;

(3)__Process water must contain no detectable coliform bacteria.__The holder of a depuration certificate pursuant to subsection 3 shall continuously treat process water and verify that the disinfection system produces process water with no detectable coliform