Interim Stabilization Measures (ISMs) are those activities which can be initiated in advance of, or supplemental to, implementation of the final corrective action for a Solid Waste Management Area, necessary to achieve the goal of stabilization.

Interim Stabilization Measures initiates cleanup and controls, or eliminates, the release or potential release of hazardous wastes or hazardous constituents at or from the Gary Works facility.

Interim Stabilization Measures that have been completed at Gary Works include:

- SWD-1 Cell IIB Expansion—Mitigation of multiple Solid Waste Management Units (SWMUs) within the footprint of the landfill expansion. Installation of bottom liner in 2018 eliminated potential for direct contact and leaching of soil to groundwater.

- East Side Benzene—Includes installation of an approximately 2,800-foot long slurry cut-off wall installed in 2013 and supplemental groundwater extraction system installed in 2014 (Phase I) and 2016 (Phase II). Extracted groundwater is conveyed and treated at the Coke Plant Wastewater Treatment Plant.

- N-Yard Coke Unloading Station—Included excavation of approximately 4,700 cubic yards of soil from East End SWMA in 2015 where a coke unloading station was to be constructed. Soil was disposed of in the CAMU following approval by USEPA.

- Shoreline West of the Vessel Slip—Includes stabilization measures implemented in 2012 on the west side of the facility to reduce shoreline erosion.

- AOC for ELA1 and ELA3—Specific areas of soil impact within these Areas of Concern (AOCs) were excavated and hauled to the CAMU for disposal.