Region 5 Superfund (SF)

U.S. EPA REGION 5
HENNEPIN COUNTY
MINNEAPOLIS

Congressional District # 05

TWIN CITIES AIR FORCE RESERVE BASE (SMALL ARMS RANGE LANDFILL)

EPA ID# MN8570024275
Last Updated: July, 2008

Site Description

The Twin Cities Air Force Reserve Base, Small Arms Range Landfill site is a two-acre landfill, located between the Minnesota River and the Minneapolis-St. Paul International Airport. The site was used as a landfill from 1963 until 1972 for the disposal of general base refuse and industrial wastes, including 100 gallons of painting waste sludge, 800 pounds of paint filters, and between 100 to 200 gallons of sludge from leaded aviation gasoline. Groundwater discharges to the Minnesota River, and the site is within the 100-year flood plain of the Minnesota River. Approximately 64,700 people, living in the Minneapolis-St. Paul metropolitan area, depend on public and private wells for drinking water within a three-mile area of the landfill. The northern boundary of the Minnesota Valley National Wildlife Refuge lies 500 feet from the landfill.

Site Responsibility

This Site is the responsibility of the United States Air Force, and has been addressed by the Air Force pursuant to the requirements of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA).  Per the federal facility agreement between the Air Force and U.S. EPA, EPA has exercised approval authority over the work that the Air Force has performed at the site.

Threats and Contaminants

Groundwater monitoring results showed that arsenic, beryllium, cadmium, lead, nickel, selenium, and vanadium contamination exceeded the Safe Drinking Water Act / maximum contaminant levels (MCLs) and the State of Minnesota groundwater standards.  

Cleanup Progress

After the U.S. Air Force Reserve (USAFR) completed the remedial investigation and feasibility study (RI/FS), a record of decision (ROD) was signed on March 31, 1992, which selected natural attenuation, site maintenance, site access restrictions, and groundwater and surface water monitoring, as the remedy for the site. The United States Environmental Protection Agency (U.S. EPA) and USAFR concluded that, due to site characteristics, natural attenuation of contamination would readily occur through adsorption, biodegradation, physical/chemical degradation and dispersion. Bimonthly groundwater and surface water monitoring were necessary to assess the quality of groundwater and surface water downgradient from the landfill and to evaluate the effectiveness of natural attenuation. 

Both groundwater well installation and construction of a fence were completed in September 1992. After results were obtained from the 1993 and 1994 sampling events and from a review of all the data that was collected during the investigative history of the site, USAFR concluded that natural attenuation has proven to be an effective remedial alternative. The site was deleted from the National Priorities List in December 1996. 

The remedy for the Small Arms Range Landfill allows hazardous wastes to remain onsite after the remedy is complete; therefore,  five-year reviews of the remedy are conducted to verify that the remedy remains protective. So far two five-year reviews have been completed at the site in 1998 and 2003. Based on the results of these reviews, the remedy remains protective of human health and the environment. Because several constituents still appear to be elevated, five-year reviews will continue to be conducted.  The USAFR has prepared the third Five Year Review, which is currently under review by U.S. EPA.  The Third Five Year Review for the TCAFR SARL will be completed in July 2008.

Property Reuse

The property belongs to the USAFR.  Public access is prohibited, the site is fenced and signs are posted.  The USAFR has no plans to dispose of the property and the institutional controls that are in place will continue.  The USAFR's site access restrictions and site maintenance program will continue.

Contacts

Remedial Project Manager, U.S. EPA
thomas barounis (barounis.thomas@epa.gov)
(312) 353-5577

Community Involvement Coordinator, U.S. EPA
dave novak
(312) 886-7478

Aliases

USAF TWIN CITIES RES SAR
TWIN CITIES AIR FORCE BASE (SMALL ARMS
SMALL ARMS RANGE LDFL
TWIN CITIES USAF RESERVE BASE
TWIN CITIES AIR FORCE BASE(SAR LANDFILL)
US AIR FORCE MINNEAPOLIS ST PAUL IAP
TWIN CITIES AF RESERVE (SAR LANDFILL)

 

Site Profile Information

This profile provides you with information on EPA's cleanup progress at this Superfund site.