ADEQ is considering closure of the following leaking underground storage tank (LUST) case:

LUST Case File No.: 5410.01

Facility ID No.: 0-009574
Maricopa County

Facility address: 
Circle K Store #2706664 (former Shell Station #120768)
17125 E. Shea Boulevard
Fountain Hills, AZ 85268

Information

The Circle K Store #2706664 is located at 17125 E. Shea Boulevard in Fountain Hills. The facility currently operates as a retail petroleum station with a car wash and convenience store. This facility was the former Shell Station #120768. The UST owner/operator was identified as Shell Oil Products US (Shell).   According to documentation, there have been an estimated six above ground storage tanks (ASTs) and two USTs were in service from 1978 until they were removed in 1998. UST closure activities were completed by the property owner in 1998. An investigation of the UST tank pit and associated piping was completed in 2000. LUST release .01 was assigned in 1999.  

Shell and its consultants have conducted corrective actions at the site since July 1999. In 2004 and 2005, Miller Brooks Environmental installed numerous soil confirmation borings in the vicinity of the LUST release and also conducted other site investigations.  No chemicals of concern (CoCs) were reported over applicable residential Soil Remediation Levels (rSRLs), or Groundwater Protection Levels (GPLs). The deepest detected CoC was methyl tert butyl ether (MTBE) at 25 feet below ground surface (bgs) in SB19-25.   In November 2007, URS Corporation (URS) assumed groundwater monitoring and other remedial activities at the site. Quarterly groundwater monitoring and sampling events occurred between November 2007 and February 2015.  URS also installed two off-site monitoring wells (MW-8 and MW-9) across Shea Boulevard east of the site in 2013.  In 2014, MW-8 was abandoned due to property development at that location, but MW-9 was retained.

GES became Shell’s consultant in February 2015. PersulfOx®, which promotes rapid and sustained in situ oxidation of a wide-range of organic contaminants like petroleum hydrocarbons, was used to remediate groundwater. Injections into specific monitoring wells occurred in May and August 2017. Groundwater results show that MTBE concentration remains above the applicable Tier 1 Corrective Action Standard of 94 µg/L in MW-1 and MW-5. The results for all other monitoring wells show no contamination present over applicable regulatory standards and the data is available in the LUST file.

Data provided by GES, and all other available site information has been used by ADEQ to determine whether remaining levels of contaminants at the site are adequately protective of human health and the environment.  A site-specific risk assessment and detailed file/information search were also completed. 

Based upon the results of remedial activities and site-specific information, the above-referenced LUST site is eligible for alternative LUST closure under Arizona Revised Statutes (A.R.S.) §49-1005(E).  Arizona Administrative Code (A.A.C.) R18-12-263.04 allows case closure of a LUST site with groundwater contamination above the Arizona AWQS or Tier 1 Corrective Action Standards.

Review Document 

Review results of remedial activities and entire public notice | View/Print >

Public Comment Period 

Dates: Sept. 26, 2018 – Oct. 26, 2018

Comments may be submitted as follows:
     By Email | Send Email > 
     By Mail (Must be postmarked or received by Oct. 26, 2018):

       ADEQ
       Debi Goodwin
       Waste Programs Division
       1110 W. Washington Street
       Phoenix, AZ  85007 

Documents may also be reviewed in person at the ADEQ Record Center | Learn More >