Motorola, Inc. (52nd Street Plant)

OU1

In 1988, the EPA and ADEQ selected an interim remedy for the site, called OU1, to clean up a portion of the Motorola facility through soil gas extraction (SVE) and groundwater pump and treatment methods. The remedy was selected to prevent further contamination to groundwater by recovering the contaminated on-site soil gas and groundwater and also capturing off-site groundwater at 44th Street.

Motorola, under ADEQ oversight, completed construction of a full-scale groundwater extraction and treatment facility, and it has been operating since 1992. On-site and off-site (at 44th Street) contaminated groundwater is being pumped and treated at an on-site treatment facility by air stripping, and the air emissions are treated with granular activated carbon. The treated groundwater is then used in the manufacturing processes, replacing water that was previously supplied by the City of Phoenix. Motorola also completed soil vapor extraction (SVE) pilot studies on the Courtyard and Southwest Parking Lot areas of the facility in 1993. Design and construction of a full scale pilot Air Sparging/SVE system in the Southwest Parking Lot area (SWPL) was completed in 1996 and operated in 1997.

STATUS: Motorola is currently evaluating the long-term effectiveness of the groundwater treatment system, and submitted an addendum to the Feasibility Study for OU1 in December 2005. Freescale is currently conducting a Bedrock Extraction Pilot Study to determine how to extract contamination from bedrock structures. This Pilot Study will occur throughout 2009-2010. The 3rd Five Year Review for the OU1 treatment system was conducted in September 2006. The purpose of the Five Year Review was to determine whether the OU1 system continues to meet the remedial action objectives and is protective of human health and the environment. Several followup actions and recommendations were identified in the Five Year Review that need to be resolved before a final determination on the system's protectiveness can be made. Freescale has worked with EPA and ADEQ to address many of these followup actions and recommendations. The remaining issues will be addressed as part of the Final Feasibility Study and Final Remedy Selection Process.

Over the past several years, ON-Semiconductor used the treated groundwater at OU1 for on-site manufacturing purposes. EPA and ADEQ recently learned that ON-Semiconductor plans to close its plant operations by October 2010. This means the company will no longer be able to use the treated groundwater. Freescale is currently developing a proposal for beneficial future use of the treated groundwater. Freescale is working with EPA and ADEQ to develop a range of short-term and long-term water use options. Freescale will continue to operate the treatment plant to ensure continued containment of the plume. EPA and ADEQ will provide more information to the community on this issue once we receive the proposal from Freescale.

EPA has the lead for the vapor intrusion to indoor air pathway investigation in OU1. Vapor intrusion is the migration of volatile organic compounds from contaminated groundwater and/or soil into overlying buildings. EPA is in the final stages of negotiating an Administrative Order on Consent (AOC) and a Statement of Work (SOW) with Freescale to perform soil gas sampling and, if needed, indoor air sampling in the residential neighborhood west of the former Motorola 52nd Street facility. Once the AOC and SOW are signed, Freescale will submit a draft Work Plan that will be shared with the community for comment. The Work Plan will identify locations where soil gas sampling is proposed. Soil gas sample data will be compared to health-based screening levels to determine if indoor air sampling is needed. EPA will work closely with the community.

OU2 Motorola, under ADEQ oversight, conducted an investigation of the groundwater contamination in the area downgradient of OU1. The contamination was discovered to extend to at least 20th Street, several miles west of the Motorola facility. Contamination from the Honeywell (formerly AlliedSignal) facility at 34th Street, and possibly other facilities, is suspected to be contributing to the groundwater contamination in the area. In 1994, ADEQ and EPA selected an interim groundwater pump and treatment remedy to contain the plume near 16th Street and treat the water to drinking water standards. This remedy was selected to prevent further spreading of contamination and to begin cleaning the groundwater in the area. The remedy is described in the 1994 Interim Record of Decision for OU2.

Motorola began the design for the OU2 remedy in late 1996 and completed the design in 1999, under ADEQ oversight. During the design process, EPA and ADEQ made two significant changes to the 1994 Record of Decision: 1) the planned end use of the treated water was changed from reinjection into the aquifer to discharge to the Salt River Project (SRP) Grand Canal for agricultural irrigation purposes, and 2) the treatment technology was modified from air stripping to granular activated carbon and ultraviolet oxidation. These changes are documented in a September 1999 Explanation of Significant Differences.

The final design was approved by ADEQ and EPA in December 1999. The system was designed to acheive capture of the plume at 20th Street in it's first year of operation. Under an EPA Unilateral Administrative Order, Honeywell and Motorola completed construction of the treatment system in August 2001 and have been operating the system since September 2001. The current system consists of 3 extraction wells, conveyance piping from the wells to the treatment plant at 20th Street and Washington, treatment (VOC removal) using granular activated carbon, piping of the treated water to the SRP Grand Canal discharge point at 35th Street east of Roosevelt, and a monitoring well netowork to evaulate system effectiveness. A UV/Ox system has also been installed at the treatment plan to address treatment of vinyl chloride should it be necessary in the future.

Over 3 million gallons of water is treated and discharged per day. The system is shut down for 1 month annually to allow for the SRP canal maintanance period. The length of time the groundwater treatment system will need to be operated has not yet been established, and will be established after final cleanup goals and a final cleanup strategy for OU 2 have been selected by EPA and ADEQ.

STATUS: The first Effectiveness Report evaluating OU2 operations was submitted to EPA in April 2003, and has been submitted to EPA annually thereafter. The treatment plant has been effective in removing contamination from the groundwater. However, since the system has been operating, groundwater levels have been declining, and extraction rates at the system have reduced overtime, particularly in the south well. The system appears to have achieved capture of the majority of the plume at 20th Street, however there is some uncertainty regarding the exact location of capture near the south extraction well. Motorola and Honeywell installed additional monitoring wells in 2007 to better define the location of capture and fill some of the data gaps identified in the 2nd Five Year Review for OU2.

Honeywell 34th Street

Facility Investigation: The Honeywell 34th Street facility is an 118-acre an aerospace manufacturing plant located at 34th Street and Air Lane, in the OU2 area. Honeywell used chlorinated solvents in its operations, including TCE and 1,1,1-TCA. Investigations to date have determined that on-site soil and groundwater, as well as off-site groundwater west of the facility, have been contaminated.

Honeywell has been conducting investigations at their site since 1992 to characterize soil and groundwater contamination on portions of the facility. They have installed approximately 33 on- and 25 off-site groundwater monitoring wells and have conducted several shallow soil gas investigations. They have also have designed, constructed and operated a pilot soil vapor extraction (SVE) system in an area of the site since 1997. Under a 1999 Administrative Order on Consent (AOC) with ADEQ, they are completing characterization of the potential soil sources at their entire facility, and installing about 31 additional groundwater monitor wells to characterize the extent of the off-site groundwater contamination. This site characterization work will support a cleanup strategy for the sources at the Honeywell facility.

STATUS: In 2007 and 2008, Honeywell conducted a field investigation of subsurface structure content on their facility. Honeywell conducted this investigation in response to: (1) the discovery of chlorinated solvent contamination in the Building 112 interceptor during an evaluation of the Facility's interceptors requested by the City of Phoenix (COP); (2) the findings of the subsurface potential source surveys conducted in March and May 2007; and (3) the environmental self-audit completed by the Facility in 2007. The complete results of this investigation will be included in an addendum to the Final Focused Remedial Investigation (FRI) Report. This report is currently being revised by Honeywell at EPA and ADEQ's request.

Honeywell is also working with ADEQ's Underground Storage Tank (UST) program to address jet fuel releases at the facility, discovered in 1999. In 2006, Honeywell applied for a revision to their existing Title V Permit to permit the air emissions from a new Biologically Enhanced Soil Vapor Extraction (BSVE) system. The BSVE System is currently operating.

OU3

Operable Unit 3 extends from 20th Street on the east to 7th Avenue on the west, and is between McDowell Road on the north and Buckeye Road on the south. EPA has the lead for oversight of PRP work to investigate and cleanup contaminants in OU3. EPA installed groundwater monitoring wells in late 2001 and in February - May 2003 in order to determine the extent of groundwater contamination from the Motorola 52nds Street Superfund site. A total of 28 new monitoring wells at 13 locations were installed. The results of this investigation are contained in a Groundwater Investigation Report dated January 2005. EPA sampled the new wells quarterly for the first year and then semi-annually (March and September). Groundwater Monitoring Reports are prepared after each sampling event.

STATUS: EPA, Honeywell International and Arizona Public Service signed a Statement of Work (SOW) and an Administrative Order on Consent (AOC) for an OU3 Remedial Investigation and Feasibility Study in September 2009. The SOW requires the installation of the final phase of groundwater monitoring wells, installation of soil vapor monitoring wells to evaluate the vapor intrusion to indoor air pathway and an in-situ treatability study. The SOW also contains tasks for determining clean-up options and performing a Baseline Groundwater Risk Assessment. The PRPs have submitted a draft Work Plan for EPA and ADEQ approval . Once the Work Plan is approved, field work to install the groundwater monitoring wells and soil vapor monitoring wells will begin.

Additional Facility Investigations: EPA seeks to identify additional companies that may have contributed to the contamination in the OU2 and OU3 areas. Since July 2000, EPA has sent over a hundred information request letters to various companies that may have information about solvent use at industrial facilities in the area. In September 2003, and again in September 2005, EPA identified additional potentially responsible parties (PRPs) to the site, and is working with the PRPs to investigate the potential contamination at these facilities. EPA initiated negotiations for facility investigations with the PRPs in March 2004 and has negotiated six agreements in OU3 to date. Additional facility investigations are planned.
ADEQ began negotiating with PRPs in the OU2 area in June 2004 and has issued one order to date. ADEQ has recently initiated additional facility investigations in the OU2 area.