Landfill Cleanup

Cleanup of the Cave Creek Landfill site has been approved by the Arizona Department of Environmental Quality and it is underway.

Please read the fact sheet (PDF) and the Remedial Action Plan (RAP) (PDF) document if you would like more information than what is provided in the "Background" and "Plan Phases" sections below.


The groundwater is not a drinking water source, but the Remedial Action Plan (RAP) (PDF)can give you more detail as to why Maricopa County and the state feels it is important to clean the site. The county has been monitoring the site since the late 90s for a common solvent often dumped in older landfills, known as TCE. We have detected vapors in the soil and in the groundwater 600 feet below the ground surface. This groundwater is not currently used a drinking source, but we want to protect it for future use. The contaminated area is spreading south from the old landfill at approximately 6 inches per year.


Plan Phases 

The approved Remedial Action Plan has led the county to drill wells in strategic areas around the landfill. Some of these are for monitoring water quality while others will pull contaminated water to the surface where it will be filtered and cleaned in a Groundwater Treatment System. The well planned for 4050 E Sleepy Ranch Rd in early 2020 is an injection well. 

Water cleaned in the Groundwater Treatment System will be piped to the injection well site and pumped deep below the surface to return clean water to the aquifer and slow the migration of contaminated water towards water supply wells.

It is important to understand this is a long-term project. Please see phase details for more information.

Phase Details

Phase One - Well Drilling
Expected Construction Time: July through November 2019  

A truck-mounted drilling rig will drill, develop, and test the well. At the well site property, the drilling company will construct a24-foot noise barrier panel system (see picture 1) to completely surround the drilling area and reduce noise and light pollution as much as possible. The drilling portion of this phase will last 3 to 4 weeks, 24 hours per day. After drilling, work will be less noisy and occur intermittently on a 24-hour schedule. Site work will include pumping the well for hydrogeologic testing. A temporary pipeline will run from the well site to a wash on the Sonoran Preserve for the discharge.

20180306_Wall-Rendering-Looking-NW-from-Sleepy-Rnch-Rd(Conceptual rendering of wall and access gate on injection well property.)

Phase One(Typical noise barrier system surrounding drill site.)

Phase Two - Pipeline Construction
Expected Timeframe: October 2019 through January 2020

A sub-grade, 8-inch diameter pipe will be installed from the off-site Groundwater Treatment System to the injection well in your neighborhood. Access to your property will be maintained. The construction will only take place during the day, but there may be times when traffic flow is interrupted. The crews will take all necessary safety precautions to cover trenches and direct traffic.

Phase One(Typical well site during well installation.)

Phase Three - Well Site Security
Expected Timeframe:  Winter 2019

A wall and gate will be built around the property. Everyeffort will be made to restrict equipment and parking to the property.

Well-Site-Layout-Map(Planned injection well site layout.)

Phase Four - Well Equipping
Expected Timeframe: Early 2020

Construction at the well site will include installation of apermanent pump with mechanical and electrical components. This will take a smallnumber of people and every effort will be made to keep activities within theproperty walls.


(Typical wellhead piping at an injection well site.)

  1. Cave Creek Landfill Project

    Physical Address
    301 W Jefferson
    Phoenix, AZ 85003


    Phone: 602-506-6453