SoundEarth began managing the environmental investigations for Andeavor, formerly known as Tesoro Corporation, for active retail gasoline stations and former fuel storage sites in 2001. SoundEarth has entered more than 10 Andeavor facilities into the Voluntary Cleanup Program, receiving NFAs of many of them. Environmental work conducted across multiple sites have included subsurface investigations, groundwater sampling, pilot studies, Remedial Design and system installation, operation of groundwater remediation systems, LUST File Review/Path Forward including UST decommissioning and installation, and remedial excavation. Remedial Action methods include groundwater pump and treat, in situ chemical oxidation (ISCO), Air-Sparge/Soil Vapor Extraction (AS/SVE), and Multi-Phase Extraction (MPE). Other tasks have included Phase I and II ESAs, RIs, FSs, CAPs, Conceptual Site Models, Alternative Cleanup Technology, Groundwater monitoring, and Remedial Design and system operation. SoundEarth has achieved regulatory closure on one site and anticipates closing another two sites within 5 years.

Remedial Action operations and maintenance activities include equipment maintenance, responding to system alarms, performance sampling, and system optimization. SoundEarth performs pilot studies to evaluate Remedial Design technologies, prepares system design specifications and drawings and requests for bid, evaluates bid responses, and manages the installation of selected remedial technologies. Other tasks include operation and maintenance of various Remedial Action systems, collecting permit compliance samples, completing quarterly Monitoring reports, and ensuring compliance with permit reporting requirements. Public Involvement/Stakeholder coordination activities include coordination with multiple local municipalities for wastewater discharge permits and regional air quality permits, state discharge permits for air and water, and reporting under the guidance provided by Ecology. SoundEarth also conducted an emergency response at a Tesoro site in 2016 that involved coordination with the public and stakeholders. The emergency response work included interfacing with emergency responders, municipal agencies, and Ecology, as well as oversight of the emergency Remedial Action activities. For another site, SoundEarth installed a system for Source Control Action to reduce the potential for off-property migration of petroleum-contaminated groundwater. Three USTs were decommissioned and 2,723 tons of petroleum contaminated soil was exported during the UST removal. SoundEarth also observed the installation of a new fueling system to replace the former USTs.