Skip to main content

PUBLIC NOTICE | Proposed Leaking UST Case Closure for Case File 4769.01-.03

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

LUST Case File No.: 4769.01-.03     

Facility ID No.: 0-009063
Yavapai County

Facility address: 
McGuireville Mini-Mart
2105 E. Beaver Creek Road
Rimrock, AZ 86335


The property is located at 2105 East Beaver Creek Road in Rimrock, Arizona. The site is currently occupied by a convenience store with fuel sales. The underground storage tank (UST) system was reportedly installed in the 1960s.  A release of petroleum hydrocarbons was discovered and three LUST releases were assigned in September 1997.  LUST release 4769.01 was assigned to the 24,000 gallon gasoline UST, LUST release 4769.02 was assigned to gasoline product piping/north of building and LUST release 4769.03 was assigned to gasoline fuel dispenser piping. LUST release 4769.04 was reported in March 2005 and was closed in August 2008.

The ADEQ State Lead Unit conducted corrective actions between 1999 and 2008. Activities included the advancement of soil borings, a groundwater monitoring and sampling program and active remediation.  A soil vapor extraction (SVE) system operated between 2001 and 2002 and remediated the soil contamination to below applicable regulatory standards. The State Lead Unit proposed to use chemical oxidation for remediation of the groundwater. The UST Owner/Operator, Reamax Oil Company, Inc. terminated their agreement with the State Lead Unit in 2008. The Site Characterization Report was approved in December 2009.  Corrective actions continued under the direction of the UST Owner/Operator.

The UST Owner/Operator contracted with O&M Inc. in 2012 to continue site activities. These activities included the advancement of shallow soil borings, groundwater remediation, a groundwater monitoring and sampling program and a soil vapor survey.

Historic boring logs indicate that a consolidated silty sandstone at 6-10 feet underlies a clayey sand.  Below the silty sandstone is a 3-6 foot clay layer over limestone. Regionally, groundwater flow is southwestward toward the Verde River, which is perennial.  Local groundwater flows westerly to southwesterly. The depth to groundwater in October 2016 was between 25 and 38 feet.

Fourteen monitoring wells were installed on and off site. Groundwater data has been collected semi-annually since July 2009. Methyl tertiary butyl ether (MTBE) and benzene have been the only Volatile Organic Compound (VOC) reported over an applicable regulatory standard since 2009.  In August 2012 and May 2013 sodium persulfate was used to treat the groundwater.  Groundwater sampling in July 2013 indicated that both benzene and MTBE concentrations were reduced in most wells but remained over the applicable regulatory standard in some of the wells.

A site specific risk assessment and detailed file/information search were also completed.  MTBE analytical groundwater results in MW-1, MW-3, MW-4 and MW-5 remain above the applicable regulatory standard of 94 µg/L.

Review Document 

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

Public Comment Period 

Dates: March 21, 2017  April 21, 2017

Comments may be submitted as follows:
     By Email | Send Email > 
     By Mail (Must be postmarked or received by April 21, 2017):

       Scott 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 >