1.1.1 Incident Category

OPA Emergency Response

1.1.2 Site Description

At approximately 1915 on September 4, 2016 EPA Region 10 received notification that the Sinclair Products Terminal (Sinclair) facility in Burley, Idaho had overflowed one of their above ground tanks and spilled 33,600 gallons (800 barrels) of gasoline into secondary containment. The Sinclair facility is located on the Tesoro pipeline that runs near the Snake River. EPA Region 10 mobilized On-Scene Coordinator (OSC) Weigel, who was accompanied by a visiting new hire employee, on September 5, 2016 after concerns regarding the adequacy and urgency of the Sinclair's response efforts necessary to keep spilled gasoline from migrating to the nearby Snake River. OSC Weigel met with Sinclair personnel and IDEQ Bobby Dye on site and agreed on a preliminary cleanup plan with IDEQ providing primary oversight of continued cleanup and monitoring by Sinclair and their contractors. EPA personnel demobilized evening of September 5, 2016.

1.1.2.1 Location

The Sinclair Burley Products Terminal is a bulk refined products terminal that includes seven 20,000 barrel (840,000 gallon) above ground storage tanks that are filled from the Tesoro pipeline that passes through the facility.  The facility is located approximately 1,000 feet south of the Snake River, approximately 3 miles west of the City of Burley, Idaho.

1.1.2.2 Description of Threat

On September 4, 2016 a spill of an estimated 800 barrels (33,600 gallons) of gasoline occurred when a tank was overfilled during a transfer operation from the Tesoro pipeline.  The spilled gasoline was contained within the facility's secondary containment system.  At the time of the spill, Sinclair was in the process of installing a liner within the previously unlined containment area.  The liner is comprised of a bentonite clay mat overlain by approximately 8 inches of gravel.   Most of the spilled gasoline reportedly remained in the lined area of the containment.  Some of the spilled gasoline reportedly migrated off of the bentonite-lined area into an as yet unlined area in the northwest corner of the containment system.  A spill response contractor was mobilized evening of September 4 and reportedly recovered an estimated 243 barrels (10,206 gallons) of product, which was trans-loaded into an empty 20,000 barrel tank at the facility.  On September 6, 2016 Sinclair issued a revised spill estimate of 647 barrels (28,308 gallons), meaning that an estimated 18,102 gallons remains unaccounted for.  A significant portion of that 18,000 gallons of unrecovered gasoline has likely been lost to evaporation, with the remainder likely remaining in saturated and contaminated soils on top of the liner, and off of the liner in native soils within the secondary containment system. 

The facility is only approximately 1,000 feet from the Snake River to the north.  Groundwater at the site is reportedly at approximately 50 feet below ground surface, and groundwater flow gradient is north towards the Snake River.  Gasoline in saturated and contaminated soils at the site within the secondary containment system, if not quickly remediated, may migrate vertically to groundwater, and then migrate laterally with groundwater flow to the Snake River.

1.1.3 Preliminary Removal Assessment/Removal Site Inspection Results

 EPA OSC met with Sinclair and IDEQ personnel on 9/7/2016 and agreed on a monitoring and cleanup plan that would be overseen primarily by IDEQ.

2.2.1 Anticipated Activities

IDEQ will continue to oversee Sinclair-lead response efforts, including excavation of contaminated soil and shipment to an approved land farm or landfill facility and continued groundwater monitoring in existing on-site monitoring wells.

2.2.1.1 Planned Response Activities

2.2.1.2 Next Steps

2.2.2 Issues

9/5/2016

EPA - 2

IDEQ - 1

Sinclair - several