Site Narrative:
Refining operations at the Coastal Derby Refinery Site began in 1920 (under the name Derby Oil Company) and continued until July 1993. In September 2004, El Paso Merchant Energy – Petroleum Company (El Paso) initiated refinery demolition activities, with major structures and associated piping being decontaminated, demolished and removed from the Site; demolition activities were completed in January 2009. On October 19, 2012, El Paso transferred ownership of the Site to Environmental Liability Transfer, Inc. (ELT). On November 29, 2012, KDHE entered into a Consent Order (CO) with El Paso and ELT to conduct a Corrective Action Study (CAS), Corrective Action Plan (CAP), and Corrective Action (CA). Prior to the execution of the November 2012 CO, a previous CO was in place, which was established in 1992.
Numerous investigations have been conducted at the Site since 1992. The investigations identified elevated concentrations of refinery-related contaminants in soil, groundwater, surface water and sediment. Light non-aqueous phase liquids (LNAPL) have been identified across much of the Site; further assessment of LNAPL characteristics, distribution and recoverability is ongoing. A Baseline Ecological Risk Assessment was approved by KDHE in July 2010 and a Human Health Risk Assessment was approved by KDHE in October 2011. Investigation results and risk assessment findings facilitated the evaluation of remedial alternatives in the CAS.
Several remediation systems have been installed to recover groundwater and LNAPL. Until demolition activities were initiated, a network of vertical recovery and injection wells were operated. LNAPL was recovered and managed off-site. Groundwater was either re-injected into upgradient injection wells or was treated before being discharged to an unnamed tributary to the West Fork of Chisholm Creek. Many of the vertical recovery wells remain at the Site; however, a majority of the associated piping was removed during demolition activities. In 2007, a series of three seep interceptor trenches were installed along the east side of the Site (both north and south of 21st Street) parallel to the East Fork of Chisholm Creek to mitigate hydrocarbon seeps into the creek. Two product recovery trenches are operating, one located on the north side of 21st Street; the other located south of 21st Street.
In May 2013 KDHE approved an Interim Measure Product Recovery Work Plan and Design, which began implementation in the Fall of 2013. Groundwater, surface water, and remedial system performance monitoring is currently ongoing at the Site. A CAS was approved in July 2016.
KDHE developed the Draft Corrective Action Decision (CAD) that was available for public comment July 25 through August 23, 2017. No comments were received. The CAD was finalized and signed by the Secretary on Sept. 12, 2017. A CAP will be developed, and a CA for the Site will be implemented.
Multi-phase extraction was conducted near trenches 2 and 5. Additional soil investigation to evaluate metals in soil for excavation has been completed and the Soil Waste Management Plan was revised based on the results. Soil containing hazardous levels of lead has been excavated (final report 2022). A seep investigation was conducted in Oct. 2020 and the area continues to be monitored.
KDHE approved the Redevelopment Plan in December 2020. Groundwater sampling continues to be conducted quarterly and trenches for hydraulic containment at the east side of the Site continue to operate. Multi-phase extraction resumed in fall 2023. |