The Guam EPA may promulgate separate regulations for monitoring and other requirements specifically for rainwater catchment systems. For the purpose of this Chapter, a rainwater catchment system is classified as a surface water system unless it meets requirements as may be specified by Guam EPA by regulation to allow classification as a groundwater system.

10 Guam Code Ann. HEALTH AND SAFETY
CH. 53 GUAM SAFE DRINKING WATER ACT