Petroleum Releases from Underground Storage Tanks in Northwest Indiana: Successful Remediation
Techniques and Implications of Cost Effectiveness
Lenz, Richard J.
ABSTRACT: Prior to the passage of the 1976 Resource Conservation and Recovery Act (RCRA) 1.6 million
bare steel Underground Storage Tanks (UST) were in use in the United States. Many of them were
leaking. In Indiana approximately 13,000 UST remain but have been upgraded to meet current industry
and regulatory standards. Cleaning up the petroleum releases from leaking UST has continued since it
became evident that bare steel underground tanks leaked. In Northwest Indiana glacial moraine and
outwash deposits from the Wisconsin Ice Age that retreated 10,000 years ago left 200 feet of glacial till
above the underlying bedrock. Soil Vapor Extraction (SVE) and Air Sparging (AS) have proven to be
effective and provide significant cost savings for remediation in the glacial deposits in Northwest
Indiana. Indiana also has the Excess Liability Trust Fund (ELTF) to help pay for and to expedite clean-up
of releases from registered UST. Cleaning up petroleum releases requires the appropriate technology for
the localized geology, adequate funding, and appropriate guidance from state and federal regulations.
This paper discusses these issues at three sites in Northwest Indiana and how technology, funding, and
regulatory compliance must collaborate to work in the field.
KEY WORDS: Air Sparging, Excess Liability Trust Fund, Glacial End Moraines, Glacial Outwash Deposits,
Indiana, Regulatory Compliance, Soil Vapor Extraction, Underground Storage Tanks