501 N. Santa Fe Site
The 501 North Santa Fe Site (Site) is a former grain handling facility located at the northwest corner of the intersection of North Santa Fe Avenue and North Street in Salina, Kansas, which is in Saline County. The facility property is zoned for light industrial use by the City of Salina. Land use to the north, south, east, and west of the facility includes a mix of industrial, commercial, and agricultural properties. Residential properties are located more than 1,200 feet to the north and southwest of the facility. The Site property is currently owned by Earlco, Inc., and is used as a warehouse and storage yard. The Site also includes areas in which contaminants of concern (COCs) have been released and/or have migrated or emanated off the property.
Public Notice
KDHE is soliciting public comments regarding a proposal to address environmental contamination at the Site. A draft Corrective Action Decision (CAD) document that outlines the proposal for cleanup is available for public review on this webpage, at the KDHE offices in Topeka, and at the Salina Public Library. Appointments to review documents in Topeka may be made by calling Pamela Green at 785-296-1935.
Public comments can be submitted by email or in writing to Pamela Green, KDHE Bureau of Environmental Remediation, 1000 SW Jackson Street, Suite 410, Topeka, KS 66612. Comments will be accepted from November 1 – 30, 2023.
Site History
The Site historically operated as an active grain storage and milling facility from the 1940s until 1991. The facility originally consisted of a large mill to the north; a series of grain storage elevators to the northeast; an office building to the east; and a brick building located along the southern site boundary, which was used as a laboratory and then as a power plant for milling operations. The Site property currently consists of the former powerhouse building, which is now used to store warehousing building materials and concrete construction equipment. The historic elevators and milling building are still in place but are considered off-site for the purposes of this CAD.
Site Investigation
In March 2001, carbon tetrachloride, chloroform, and 1,2-dichloroethane (1,2-DCA), as well as several other chlorinated hydrocarbons and petroleum compounds, were detected in groundwater during KDHE’s preliminary assessment of the Elm and Front Street Site. The distribution of contaminants in groundwater suggested that a grain handling facility located on the northwest corner of Santa Fe Avenue and North Street was a source area. A leaking above-ground storage tank (AST), formerly located at the northeast corner of a brick building at the Site, released grain fumigants composed primarily of carbon tetrachloride in late 1969 or early 1970's and is believed to have contributed to the groundwater contamination.
After no active, viable responsible party for the grain fumigant release could be found, the Site was transferred to the Orphan Sites Unit in 2005. KDHE conducted a series of investigations to delineate and characterize the source area and to evaluate possible source removal options. Results of a 2005 investigation identified elevated concentrations of carbon tetrachloride, 1,2-DCA and other constituents in soil at the former location of the AST. Groundwater sampling identified a long narrow plume of carbon tetrachloride and 1,2-DCA originating from the source area towards the City of Salina's downtown public water supply well field.
In 2007, Koch Agriculture Company (KAC) entered into a Settlement Agreement and Consent Order with KDHE under the State Cooperative Program to conduct a Comprehensive Investigation (CI) and Corrective Action Study (CAS) at the Site. The CI was conducted in phases from 2007-2009 and included collection of soil and groundwater samples, installation of monitoring wells and membrane interface probes, and hydraulic testing. A CI Report and CI Addendum 1 Report were approved by KDHE in 2009 and 2010, respectively.
Interim Remedial Measures
- In 2005 KDHE initiated source area interim remedial measure (IRM) activities, which included installing five large diameter borings (LDB) to depths of 40 feet. KDHE removed and properly disposed of more than 220 tons of contaminated soil from the source area. The LDBs were completed with air sparge (AS) and soil-vapor extraction (SVE) wells to address remaining soil and groundwater issues. In 2006 an Environmental Use Control Agreement (EUCA), No. 06-EUC-0002, was recorded to document land use controls associated with the remaining impacts. KAC continued operation of the AS/SVE system through 2012.
- In 2010 a groundwater extraction system was installed downgradient of the source area in order to provide hydraulic control of impacted groundwater and mitigate migration to the public water supply wells. The system consisted of three extraction wells with two treatment buildings where groundwater passed through an air stripper. The treated effluent was discharged through the City’s storm sewer to a National Pollutant Discharge Elimination System-permitted outfall.
- In 2012 an IRM pilot study for Electrical Resistivity Heating (ERH) thermal treatment in the source area was implemented. Due to its success, a full-scale ERH system was constructed in December 2014, and the AS/SVE system was decommissioned. The ERH system continued operation until July 31, 2015. Post-ERH monitoring began in November 2015 and continues to date. An ERH Completion Report was submitted and subsequently approved in March 2018.
The groundwater extraction treatment system operated at full capacity through 2018, when KDHE approved the shutdown of recovery well RW-1. RW-1 is closest to the source area. Ceasing operation had an overall beneficial effect in flushing the remaining plume by eliminating the stagnation point. Recovery wells RW-2 and RW-3 continued operation to ensure maintenance of control of the dissolved plume.
Downgradient recovery well RW-3 had captured approximately 39 million gallons, but only approximately 0.22 pounds of VOCs in 2019. A 6-month trial shutdown of RW-3 was conducted starting in July 2019. It appeared that most of the recoverable mass from the distal portion of the plume had been removed. Decreasing concentrations observed in downgradient wells following shutdown suggest that mass is not migrating downgradient of RW-3, so RW-3 has remained offline.
Operation of recovery well RW-2, also located downgradient, continued until 2022. A dramatic reduction of 1,2-DCA concentrations from 500 micrograms/Liter (g/L) in 2010 to 3.6 g/L in October 2021 demonstrates successful source mass reduction. KDHE approved the shutdown of RW-2, and extraction ceased in January 2022.
Current Activities
Evaluation of results from recent sampling events supported the permanent shutdown of the hydraulic containment system. Residual contaminants in groundwater continue to be monitored.
KDHE Site Documents
- Draft Corrective Action Decision, November 2023 (pdf)
- First 2023 Semi-Annual Progress Report for January – June 2023 (pdf)
- Corrective Action Study, May 2021 (pdf
- Electrical Resistance Heating Completion Report, March 2018 (pdf)
- Comprehensive Investigation, June 2009 (pdf)
- Administrative Settlement Agreement and Consent Order, April 2007 (pdf)