Site Narrative:
On July 24, 1989, a Kansas Turnpike Authority tractor mower struck and sheared off a valve on the Phillips Pipeline, resulting in a release of unleaded gasoline, occurring immediately south of the eastbound entrance ramp onto I-70 at 57th Street in Kansa City, approximately 200 feet west of Brenner Heights Creek. Product was released onto the interstate, onto the ground surface in the immediate vicinity of the release, and into a ditch north of the release area.
In response, U.S. EPA mobilized a response team to oversee initial response efforts. Water flushing activities conducted on highway overpasses performed by the local fire department during initial response efforts resulted in some of the product being flushed into nearby Brenner Creek. Product observed in the Creek was contained with hydrophobic booms and removed by vacuum trucks. An estimated 400 barrels of product was recovered and approximately 460 cubic yards of hydrocarbon-impacted soil was removed as part of the initial site remediation/response activities. EPA concluded that petroleum products may have been released to groundwater and that additional investigation was necessary.
Phillips Pipe Line (PPL) Company (now Phillips 66 Company-Respondent) entered into an agreement with KDHE on April 3, 1997, to address contamination at the Site. Prior to and after entering into this agreement, PPL implemented multiple phases of investigations and evaluation assessments at the Site between 1990-1999 to further characterize site physical conditions and determine the extent of petroleum hydrocarbons in groundwater downgradient of the release area. Site activities performed in the 1990's are reported in the following documents: Preliminary Site Characterization Report (dated Jan. 24, 1991), Follow-On Field Investigation and Site Investigation Report (August 1991), Site Characterization Report (July 1992), and Subsurface Site Investigation Report (March 1995).
A Corrective Action Study Plan and Monitoring Work Plan was submitted in January 1996 to evaluate several potential remedial technologies, including soil vapor extraction (SVE) and aquifer air sparging (AS). This remedy was selected and a pilot test was conducted later in 1996. Two studied followed the remedy test and implementation of groundwater monitoring: Site Conceptual Model and Natural Attenuation Assessment Report (April 1999), and Intrinsic Bioremediation Evaluation Report (January 2000). A second SVE/AS pilot test was conducted in 2003 to evaluate the effectiveness of the SVE/AS for the remediation of petroleum-contaminated material. The SVE system was installed in March 2006 and continued operating until 2009, when operations were discontinued due to decreasing hydrocarbon soil vapor recovery. Additional data was collected in late 2011 to determine if remedial actions at the Site could be optimized.
In June 2012, Interim Remedial Measures Work Plan was submitted to deliver oxygen to groundwater in order to enhance bioremediation of the dissolved-phase contaminants through the SVE System. A more aggressive approach for oxygen injection systems, in-situ ISOC treatment, was proposed and approved in August 2012 in a second IRM work plan, Interim Remedial Measures Work Plan- Matrix Injection System. The system was implemented in October 2012 and operated until December 2019.
In April 2015, a Groundwater Monitoring Plan was approved to conduct long term groundwater quality monitoring at the Site. Semi-annual groundwater monitoring and sampling was conducted to provide consistent evaluation of site conditions. This semi-annual schedule continued until 2023.
The Corrective Action Study was submitted in July 2025 and evaluated potential remedial alternatives using a standardized framework to assess effectiveness, implement ability, and investigate whether pursuing reclassification is appropriate. KDHE is currently drafting an Agency Decision Statement (ADS) which has to be submitted for public comment prior t o finalization. The public comment period for the document will be August 25, 2026, through September 9, 2026. |