2025 – 2026: The Tucson Airport Authority (TAA) conducted field activities for the per- and polyfluoroalkyl substances (PFAS) Remedial Investigation.

2025: The Tucson International Airport Final Quality Assurance Project Plan, Remedial Investigation of PFAS was prepared.

2024: The TAA and the U.S. Environmental Protection Agency (EPA) entered into an agreement to address PFAS in groundwater. The TAA issued a Final Preliminary Assessment Report for Aqueous Film-Forming Foam (AFFF) Areas at Tucson International Airport.

2023: EPA issued the Third Five-Year Review Report for the Tucson International Airport Area (TIAA) Superfund site. A Revised Conceptual Site Model was published for the Airport Property.

2019: TAA issued the In-Situ Chemical Oxidation Pilot Test Closure Report for the Samsonite Building Area.

2018: EPA issued the Second Five-Year Review Report for the TIAA Superfund site.

2016: TAA issued the Remedial Action Completion Report for the polychlorinated biphenyls (PCBs) soils remedy.

2015: A vapor intrusion investigation was completed for the neighborhood immediately west of the Airport Property Three Hangars area. Results showed that vapor intrusion was not a significant health concern.

2013: At the urging of the Arizona Department of Quality (ADEQ), and with EPA approval, the Settling Defendants performed soil boring and groundwater investigations under and near the Three Hangars Building and in Off-Airport Property areas directly west of the Airport Property. EPA issued the First Five-Year Review Report for the TIAA Superfund site.

2012: At the Three Hangers area, pipeline sludges contaminated with PCBs above 0.76 milligrams per kilogram were excavated and removed.

2011: The Tucson Airport Area Landfill was capped.

2007: EPA provided an Operational and Functional Determination for the Shallow Groundwater Zone remedy and soil vapor extraction remedy. The Airport Property started operating a groundwater and soil vapor treatment system (operates to present). 

2005: Proposal submitted to characterize carbon tetrachloride in the Shallow Groundwater Zone at West End of Runway 3. Between July 26, 2005, and Aug. 11, 2005, as part of a pilot test, approximately 7,276 pounds of potassium permanganate solution was pumped into injection wells at Samsonite Building Area.

2004: The final Shallow Groundwater Zone remedy and soil vapor extraction remedy design report (Final Report) and a Remedial Action work plan were submitted and approved.

2003: ADEQ provided funding, from EPA, for the Pima Department of Environmental Quality to perform an ongoing private well monitoring program called the South-Side Private Well Monitoring Program, for 1,4-dioxane and other contaminants.

2002: ADEQ sampled and analyzed private water wells for 1,4-dioxane as part of the South-Side Private Well Monitoring Program. Five extraction wells were installed in gravel subunits to cut off the shallow groundwater zone from the Tucson Airport Remediation Project plume.

2001: EPA issued an Explanation of Significant Differences to the September 1997 Record of Decision (ROD): Airport Property — Soils and Shallow Groundwater Zone; Burr-Brown Property — Soils; Former West-Cap Property — Soils.

2000: A Consent Decree was signed between EPA and the potential responsible parties for cleanup.

1997: EPA issued a ROD which covered soils at Burr-Brown, West-Cap, and soils and shallow groundwater at the Tucson Airport Area. The ROD concluded, EPA has determined that the low levels of volatile organic compounds in soils at the Burr-Brown Property do not pose a risk to human health or groundwater quality, and, therefore, no soil cleanup action is needed. Burr-Brown Corporation will continue to operate its groundwater treatment system pursuant to the Groundwater ROD, dated 1988. Between March and May, excavation of PCB‐contaminated soil (El Vado Residential Neighborhood and Three Hangars Area) was performed.

1996: A Final Remedial Investigation report for soil and shallow groundwater zone was issued.

1995 – 1996: Daniel B. Stephens & Associates completed the Remedial Investigation of the shallow groundwater zone and vadose zone.

1995: Tucson community members formed a Community Advisory Group called the Unified Community Advisory Board.

1992: EPA issued a Unilateral Order (UAO; Docket No. 92‐09, July 9, 1992) to Tucson Airport Authority, City of Tucson, General Dynamics Corporation, and McDonnell Douglas Corporation, for performance of a Remedial Investigation/Feasibility Study of the TIAA Superfund site.

1988: The Feasibility Study for Groundwater Remediation in the Tucson Airport Area report was released for public review and comment.

1987: EPA sent general notice letters to the potentially responsible parties, officially notifying them of their potential liability for groundwater remedy north of Los Reales Road.

1985: The Arizona Department of Health Services completed the draft final Remedial Investigation for the area north of Los Reales Road. The Arizona Department of Water Resources conducted a feasibility study.

1983: The TIAA Superfund site was added to the National Priorities List (NPL) on Sept. 8, 1983. Soon thereafter, the Air Force began an extensive investigation of groundwater contamination at the Air Force Plant 44 site, which revealed high levels of trichloroethylene in the groundwater.

1982: The TIAA Superfund Site was listed on Expanded Eligibility List, a preliminary NPL.

1954 – 1958: The Douglas Aircraft Company occupied the hangars. The plant's primary function was the modification of new aircraft, although some overhauling of older commercial planes took place.

1952: A groundwater sample from a municipal supply well indicated elevated levels of chromium. Residents complained of foul‐smelling water.

1950: From 1950 to 1954, the Grand Central Aircraft Company occupied the hangars. The company's work was defense-related, consisting largely of de-mothballing and refurbishing World War II-vintage 8-29 bombers for use in the Korean War.

1948: The Tucson Airport Authority was formed.

1942: Industrial use and disposal of metals, chlorinated solvents and other hazardous wastes began. From approximately 1942 to 1948, Consolidated Aircraft Company occupied space in the airport hangars. Between 1942 and 1945 it operated as a new-airplane modification facility. The primary plane worked on was the B-24 Liberator; other planes included the P-51 Mustang fighter and some B-29 Superfortress bombers.

1941: Around this time, large hangars were built west of the runways; these hangars were enlarged later.

1940: The Tucson International Airport was constructed in 1940 as the Tucson Municipal Airport.