GRESCO is a locally owned and established Guam company. GRESCO is comprised of several divisions including a Refinery, Environmental, LP Gas Products and Supply, Wastewater, Plumbing, Electrical Supply & Lighting, and Chemical Supply Division each with a dedicated staff, equipments, and resources to address any of your needs.

GRESCO is a leader on Guam, the Marianas, and Micronesia in the proper management of Regulated Waste, Environmental Consulting, Site Assessments, Petroleum Transportation, Waste Oil Management/Collection/Mitigation, Wastewater Management/Collection/Mitigation, Bio-Fuel Production, LP Gas Supply, Electrical Supply, Lighting, and Chemical Supply. more...