Fuel Oil Impact Beneath and Adjacent to Airport Parking Garage
Remedial Alternatives ​Pilot Study
Warwick, Rhode Island

Background:
Environmental Strategies & Management, Inc. was subcontracted to strengthen the remediation evaluation, design and operation capabilities for work at the T.F. Green InterLink facility.  We reviewed documents that described previously implemented remedies, previous site conditions, and current site conditions.  We worked with RIDOT project managers and environmental advisors to develop plans to evaluate in-situ chemical oxidation, a remedy that the previous consultant had recommended to RIDOT and RIDEM. 

Project Description:
ES&M developed a pilot study plan to test the effectiveness of in-situ chemical oxidant injections and in-situ chemical reduction injections. We were challenge to determine if this remedial alternative could be conducted efficiently and safely. This remedy requires careful consideration into work area constraints,  equipment and materials that would be needed, and how to safely store and transport the chemicals that would be used. In addition we were challenged to minimize disruption to the use of the parking facility.
 
Pre-Injection Work Plan included:
• Installation of replacement groundwater monitoring wells
• Development of existing wells to remove sediment and promote better aquifer communication
• Collection of groundwater samples for measurement of certain field parameters and laboratory analysis
• Hydraulic testing (clean water injection) of certain wells to determine if they were suitable for injection of oxidant solution

Injection and Monitoring
• Injection of oxidant (sodium persulfate) and activator (sodium hydroxide) into select wells
• Injection of oxidant (unactivated) into select wells 
• Monitoring of groundwater elevation, measurement of certain parameters in the field, and collection
of groundwater samples for laboratory analysis

Based on the results of the pilot tests, documented in a Limited Design Investigation (LDI), a RIDEM Remedial Action Work Plan (RAWP) was developed to describe a remedy that includes injection of sodium hydroxide activated sodium persulfate (in-situ oxidation) into the north and south source areas and injection of EHC® solution (in-situ chemical reduction) into downgradient wells.