Environmental testing for Arizona construction projects involves the laboratory analysis of soil, groundwater, surface water, and air samples to identify contamination, assess regulatory compliance, and verify site safety before, during, and after construction activities. Required under federal and Arizona Department of Environmental Quality (ADEQ) regulations, this testing covers contaminants including heavy metals, petroleum hydrocarbons, volatile organic compounds, PFAS, pesticides, and asbestos in soils.

Why Environmental Testing Is Essential for Arizona Construction

Arizona’s construction industry is among the fastest growing in the nation. The Phoenix metropolitan area alone issued over 40,000 residential building permits in 2024, and commercial and industrial development continues to expand across Tucson, Prescott, Flagstaff, and communities throughout the state. This growth means new construction is increasingly occurring on land with prior industrial, agricultural, or military use, sites where environmental contamination may be present.

Environmental testing protects construction projects from several critical risks:

• Regulatory liability: Under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), property owners can be held responsible for contamination cleanup costs regardless of whether they caused the contamination. Proper environmental testing before acquisition or development is the primary defense against inheriting legacy liability.
• Worker safety: OSHA requires that construction workers be protected from exposure to hazardous substances. Without environmental testing to characterize site conditions, contractors cannot implement appropriate health and safety measures, potentially exposing workers to harmful contaminants.
• Project delays and cost overruns: Discovering contamination mid-construction is exponentially more expensive and disruptive than identifying it during the planning phase. Environmental testing during due diligence allows project teams to account for remediation costs, adjust construction methods, and plan realistic timelines.
• Lender and investor requirements: Banks, SBA lenders, and commercial real estate investors routinely require Phase I and Phase II Environmental Site Assessments before financing property transactions. Projects without adequate environmental testing may be unable to secure financing.
• Public health protection: Construction on contaminated land can mobilize contaminants through dust generation, excavation, and changes to groundwater flow patterns, potentially affecting neighboring properties and communities.

Phase I Environmental Site Assessments

A Phase I Environmental Site Assessment (ESA) is the standard first step in evaluating a property’s environmental condition. Conducted in accordance with ASTM Standard E1527-21, a Phase I ESA is a non-invasive investigation that identifies recognized environmental conditions (RECs) through historical research, regulatory database review, site reconnaissance, and interviews.

What a Phase I ESA Includes

The Phase I ESA process involves several components:

• Historical use research: Review of historical aerial photographs, fire insurance maps (Sanborn maps), city directories, building permits, and other records to determine how the property and surrounding area have been used over time. In Arizona, this research often reveals prior agricultural operations (with associated pesticide and fertilizer use), mining activities, military operations, gas stations, dry cleaners, and industrial facilities.
• Regulatory database review: Search of federal, state, and local environmental databases to identify documented contamination sites, underground storage tanks, hazardous waste generators, and enforcement actions on or near the property. Key databases include the EPA’s CERCLIS and Brownfields lists, ADEQ’s Water Quality Assurance Revolving Fund (WQARF) sites, and the ADEQ underground storage tank registry.
• Site reconnaissance: Physical inspection of the property and accessible adjoining properties to identify visible evidence of current or past contamination, including stained soil, distressed vegetation, abandoned drums or containers, fill material, and evidence of underground storage tanks.
• Interviews: Conversations with current and past property owners, occupants, and local government officials to gather information about property use and any known environmental issues.

When a Phase I ESA Triggers Further Investigation

If the Phase I ESA identifies recognized environmental conditions, the environmental consultant will typically recommend a Phase II ESA to investigate the identified concerns through actual sampling and laboratory analysis. Common Phase I findings that trigger Phase II investigation in Arizona include:

• Historical use as a gas station, auto repair facility, or dry cleaner
• Proximity to a documented ADEQ WQARF or EPA Superfund site
• Evidence of fill material of unknown origin
• Historical agricultural use with potential pesticide contamination
• Former mining operations or ore processing
• Military base proximity with potential PFAS or munitions contamination
• Presence of registered or suspected underground storage tanks

Phase II Environmental Site Assessments: Where Laboratory Testing Begins

A Phase II ESA involves the collection and laboratory analysis of soil, groundwater, soil vapor, and sometimes indoor air samples to determine whether contamination identified as a potential concern in the Phase I actually exists and at what concentrations. This is where the quality of your analytical laboratory directly affects project outcomes.

Soil Testing for Construction Projects

Soil sampling is the most common component of Phase II investigations in Arizona. Samples are collected from borings advanced to various depths depending on the contaminants of concern and the planned construction activities. Common soil analyses for Arizona construction projects include:

• RCRA 8 metals (arsenic, barium, cadmium, chromium, lead, mercury, selenium, silver): Required for virtually every Phase II investigation. Arizona soils naturally contain elevated levels of arsenic, which complicates the interpretation of results and requires comparison to both regulatory standards and local background concentrations.
• Total petroleum hydrocarbons (TPH): Analyzed by methods such as EPA 8015 for gasoline-range and diesel-range organics. Essential for sites with former fuel storage, vehicle maintenance, or industrial operations.
• Volatile organic compounds (VOCs): Analyzed by EPA Method 8260. Includes compounds like benzene, toluene, ethylbenzene, xylenes (BTEX), trichloroethylene (TCE), and tetrachloroethylene (PCE). TCE contamination from aerospace and electronics manufacturing is a significant issue in the Tucson area, particularly near the Tucson International Airport Superfund site.
• Semi-volatile organic compounds (SVOCs): Analyzed by EPA Method 8270. Includes polycyclic aromatic hydrocarbons (PAHs), phenols, and phthalates. Relevant for sites with former industrial operations, fuel spills, or waste disposal.
• Pesticides and herbicides: Analyzed by EPA Methods 8081 and 8151. Critical for former agricultural land, which is increasingly common in Arizona’s expanding suburban and exurban development areas. Organochlorine pesticides like DDT and its breakdown products can persist in Arizona soils for decades due to the arid climate.
• PFAS in soil: An emerging concern analyzed by modified EPA Methods. Sites near military installations, fire training areas, and industrial facilities where aqueous film-forming foam (AFFF) was used may have significant PFAS soil contamination.

Groundwater Testing

Groundwater sampling is required when contamination may have migrated below the soil surface to reach the water table, or when the construction project involves dewatering, foundation work, or any activity that will interact with groundwater. Arizona’s complex hydrogeology, including perched aquifers, fractured rock aquifers, and basin-fill alluvial aquifers, requires careful consideration of groundwater flow patterns and contamination transport pathways.

Common groundwater analyses mirror the soil parameters listed above, with the addition of dissolved metals, general chemistry parameters (pH, conductivity, dissolved oxygen), and water quality indicators that help characterize groundwater conditions and contaminant mobility.

Soil Vapor Testing

Vapor intrusion assessment has become an increasingly important component of Phase II investigations, particularly for sites with volatile organic compound contamination. Soil vapor samples are collected from probes installed in the subsurface and analyzed for VOCs that could migrate through building foundations and accumulate in indoor air. ADEQ has adopted vapor intrusion screening levels that construction projects must consider when VOC contamination is present.

Arizona-Specific Environmental Considerations for Construction

Several environmental factors are unique to Arizona or significantly more prevalent in the state than elsewhere, and construction project teams need to account for them in environmental testing programs.

Naturally Occurring Arsenic

Arizona’s geology produces naturally elevated arsenic levels in soil and groundwater across much of the state. Background arsenic concentrations in Arizona soils commonly range from 5 to 30 milligrams per kilogram (mg/kg), with some areas exceeding 50 mg/kg. The ADEQ residential soil remediation level for arsenic is 10 mg/kg, which falls within the range of natural background in many Arizona locations.

This creates a complex regulatory and practical challenge for construction projects. When soil testing reveals arsenic above the remediation level, project teams must determine whether the arsenic is naturally occurring or anthropogenic (caused by human activity) because the regulatory implications differ significantly. AATLS can analyze soil samples for arsenic speciation and compare results against established Arizona background databases to support this determination. Visit our testing services page for details on our soil analysis capabilities.

Former Agricultural Land

Arizona’s agricultural heritage means that much of the land now being developed for residential and commercial use was previously farmed. Decades of pesticide and herbicide application, fertilizer use, and irrigation with potentially contaminated water can leave residual contamination in soils. Organochlorine pesticides (DDT, DDE, dieldrin, chlordane) are particularly persistent in Arizona’s arid soils, where limited rainfall and biological activity slow degradation.

Construction on former agricultural land should include pesticide analysis as part of the Phase II investigation, particularly if the planned use involves residential development, schools, childcare facilities, or other sensitive land uses.

Mining Legacy

Arizona’s rich mining history has left a legacy of contamination at sites across the state. From the copper mines of Globe-Miami and Bisbee to the uranium mines of the Arizona Strip and the gold and silver operations throughout the central highlands, mining activities have distributed heavy metals, acid mine drainage, and processing chemicals across vast areas. Construction projects in or near historic mining districts should include comprehensive metals analysis and may require site-specific risk assessments based on the mining activities that occurred.

Military Installation Contamination

Arizona hosts numerous active and former military installations, many of which have documented environmental contamination. The most common contaminants associated with military sites include PFAS from AFFF use, TCE and other chlorinated solvents from degreasing operations, petroleum hydrocarbons from fuel storage and distribution, and in some cases munitions constituents and unexploded ordnance.

Construction projects on or near military installations should incorporate PFAS testing and expanded VOC analysis into their environmental testing programs. The Department of Defense’s Environmental Restoration Program maintains information about known contamination at active and closed military sites.

ADEQ Brownfield Program and Voluntary Remediation

Arizona’s Brownfield Redevelopment Program, administered by ADEQ, provides a framework for the investigation and cleanup of contaminated properties to facilitate redevelopment. Understanding this program is essential for construction projects on sites with known or suspected contamination.

What Are Brownfields?

Brownfields are properties where the presence or potential presence of contamination complicates expansion, redevelopment, or reuse. The EPA estimates that there are more than 450,000 brownfield sites across the United States. In Arizona, brownfields are concentrated in older urban areas of Phoenix, Tucson, Mesa, and other cities where historical industrial and commercial activities occurred.

ADEQ’s Voluntary Remediation Program (VRP)

ADEQ’s VRP allows property owners and prospective purchasers to voluntarily investigate and clean up contaminated properties under ADEQ oversight. Key benefits of the VRP include:

• Regulatory certainty: ADEQ provides written approval of investigation and remediation work plans, ensuring that the cleanup meets state standards.
• Liability protection: Upon successful completion of the VRP, ADEQ issues a No Further Action (NFA) letter or a closure letter that provides assurance to lenders, investors, and future property owners that the environmental issues have been adequately addressed.
• Flexibility: The VRP allows risk-based cleanup standards that account for the planned land use, potentially reducing cleanup costs compared to generic residential standards.
• Tax incentives: Arizona offers tax credits and incentives for brownfield redevelopment that can offset investigation and remediation costs.

WQARF Sites and Construction

The Water Quality Assurance Revolving Fund (WQARF) is Arizona’s state Superfund program for sites with groundwater contamination. There are currently over 30 active WQARF sites in Arizona, with additional sites in various stages of investigation. Construction projects near WQARF sites require careful environmental assessment because contamination plumes may extend beyond the boundaries of the listed site.

ADEQ maintains a registry of WQARF sites that developers and project teams should review during the planning phase. If your construction project is located within or adjacent to a WQARF site, early coordination with ADEQ is essential to understand any restrictions or requirements that may apply.

Remediation Verification Testing

When contaminated soil or groundwater must be removed or treated as part of a construction project, remediation verification testing confirms that cleanup goals have been achieved. This testing is a critical regulatory requirement and must be performed by an accredited laboratory using approved methods.

Confirmation Sampling After Soil Removal

After contaminated soil is excavated, confirmation samples are collected from the floor and sidewalls of the excavation to verify that remaining soil meets applicable cleanup standards. The number and location of confirmation samples depends on the size of the excavation, the contaminants of concern, and the regulatory program overseeing the cleanup. Typical requirements include one sample per 25 linear feet of sidewall and one sample per 900 square feet of excavation floor, with additional samples at any visible staining or odor.

Post-Remediation Groundwater Monitoring

Groundwater remediation verification typically requires multiple rounds of sampling over months or years to demonstrate that cleanup levels have been achieved and are sustained. This monitoring may be required as a condition of ADEQ VRP closure or as part of an ongoing environmental management plan for the property.

Waste Characterization

Contaminated soil and groundwater removed during construction must be characterized for proper disposal. Waste characterization testing determines whether the material is hazardous waste under RCRA, which affects disposal options and costs. Testing typically includes toxicity characteristic leaching procedure (TCLP) analysis for RCRA hazardous characteristics and may include additional parameters required by the receiving disposal facility.

Construction Stormwater and Erosion Control Testing

Arizona construction projects disturbing one or more acres of land require coverage under the Arizona Pollutant Discharge Elimination System (AZPDES) Construction General Permit. This permit includes monitoring requirements for stormwater discharges from the construction site.

Stormwater Monitoring Requirements

While Arizona’s arid climate means that stormwater events are infrequent, when they occur, particularly during the monsoon season from June through September, they can be intense. Construction stormwater monitoring typically includes visual inspections of all stormwater control measures after each qualifying rain event, benchmark monitoring for pH, turbidity, and total suspended solids, and analytical monitoring for sites with potential exposure to specific contaminants.

Monsoon storms can mobilize large quantities of sediment from disturbed construction sites in a short period, making effective erosion and sediment control measures critical for permit compliance. Turbidity levels in construction stormwater discharges during monsoon events can exceed thousands of nephelometric turbidity units (NTU) if controls are inadequate.

Dewatering Discharge Testing

Construction projects that encounter groundwater during excavation may need to pump and discharge groundwater. If the groundwater may be contaminated, or if it is discharged to a surface water or storm drain, analytical testing is typically required to demonstrate that the discharge meets applicable water quality standards. ADEQ or the receiving municipality may require testing for metals, VOCs, petroleum hydrocarbons, and other parameters depending on site conditions.

Choosing an Environmental Testing Laboratory for Arizona Construction

The quality and reliability of environmental testing data directly affects project decisions, regulatory outcomes, and liability exposure. Selecting the right laboratory is a critical decision for any construction project involving environmental work.

Key Selection Criteria

• ISO/IEC 17025 accreditation: This international standard for laboratory competence is the baseline requirement for environmental testing. Results from non-accredited laboratories may be rejected by ADEQ, lenders, and other stakeholders.
• Method coverage: The laboratory must be accredited for the specific EPA methods required for your project. Environmental testing involves dozens of different methods, and no laboratory is accredited for all of them. Verify that the methods you need are on the laboratory’s scope of accreditation.
• Arizona experience: A laboratory that understands Arizona’s unique environmental challenges, from naturally occurring arsenic to the specific regulatory requirements of ADEQ’s VRP and WQARF programs, can provide more relevant guidance than one operating entirely out of state.
• Turnaround time: Construction schedules are unforgiving. A laboratory that can deliver results within 3 to 5 business days for standard analyses, with rush options available, helps keep your project on track.
• Data deliverables: Environmental projects typically require Electronic Data Deliverables (EDDs) in specific formats for import into environmental databases. Confirm that the laboratory can provide data in the format required by your consultant and by ADEQ.

Why AATLS for Construction Environmental Testing

AATLS is an ISO/IEC 17025 accredited analytical laboratory based in Tucson, Arizona, with specific expertise in the environmental testing needs of Arizona construction projects. Our capabilities include full RCRA metals analysis with Arizona-specific arsenic background data knowledge, TPH analysis by EPA Methods 8015 and 8260 for petroleum-impacted sites, VOC and SVOC analysis for solvent and industrial contamination, pesticide and herbicide analysis for former agricultural sites, PFAS testing by EPA Methods 533 and 537.1 for military-adjacent sites, waste characterization and TCLP analysis for disposal determination, and stormwater and dewatering discharge analysis.

Our Tucson location at 9030 S Rita Rd, Suite 320 means shorter shipping times for Arizona projects, and our team has direct experience working with ADEQ programs including the VRP and AZPDES permitting. We understand the regulatory context behind the numbers on your report, and we are available to discuss results and their implications for your project. Learn more about our accreditations and testing services.

AATLS is led by Dr. Glenn Cherry, an Air Force veteran and scientist committed to providing Arizona’s construction industry with the reliable, timely environmental data needed to build with confidence. Learn more about us.