Environmental Engineering in Illinois

Illinois is the sixth-largest environmental engineering market in the nation — 2,052 employed professionals ranked #6 nationally at a $94,000 average salary — reflecting the state's deep industrial history, Great Lakes water quality responsibilities, highly sophisticated environmental regulatory program, and the environmental compliance demands of Chicago's massive industrial and commercial economy. Illinois environmental engineering is shaped by legacy industrial contamination from steel, chemical, and petroleum refining operations; Lake Michigan water quality and shoreline protection; and the ongoing remediation of thousands of leaking underground storage tank (LUST) sites and Superfund properties across the state. Major Employers: The Illinois Environmental Protection Agency (IEPA) is the state's primary environmental regulatory agency — one of the nation's most sophisticated state EPAs — employing environmental engineers across its Bureau of Water (NPDES permitting, water quality standards, source water protection), Bureau of Air (stationary source permitting, air quality monitoring), Bureau of Land (Superfund, LUST, solid and hazardous waste), and the Site Remediation Program (SRP). The Illinois Pollution Control Board (IPCB) serves as the state's independent environmental adjudicatory body. Major consulting firms have their largest Illinois offices in Chicago and surrounding suburbs — AECOM, Arcadis, Tetra Tech, CDM Smith, Stantec, and Brown and Caldwell collectively employ hundreds of Illinois environmental engineers. Industrial employers are significant — Marathon Petroleum (Robinson refinery), Exelon (nuclear power plant fleet), Caterpillar (Peoria), U.S. Steel (former South Works area environmental work), and the extensive Chicago-area chemical distribution industry employ in-house environmental engineers. The Metropolitan Water Reclamation District of Greater Chicago (MWRD) — the wastewater utility serving 5.2 million people in the Chicago metro — is one of the nation's most sophisticated environmental engineering employers, managing complex nutrient reduction, combined sewer overflow control, and biosolids management programs. Key Practice Areas: LUST and petroleum remediation is Illinois's single largest environmental engineering practice — the state has approximately 28,000 LUST cases on record, and while many are completed, thousands remain active under IEPA's LUST program. Illinois's "tiered approach" to cleanup (TACO — Tiered Approach to Corrective Action Objectives) is one of the nation's most technically sophisticated risk-based cleanup frameworks, requiring environmental engineers with strong risk assessment skills. Site remediation under IEPA's Site Remediation Program (SRP) governs voluntary cleanup of thousands of Illinois contaminated sites — brownfield redevelopment in Chicago and the surrounding collar counties drives enormous environmental engineering demand for Phase I/II ESAs and SRP-governed cleanups. Lake Michigan water quality engineering is a major Illinois practice — the state's NPDES permits for Chicago-area industries and municipalities must protect Lake Michigan water quality under the Great Lakes Water Quality Agreement and Illinois's Antidegradation Policy, creating technically demanding permit development and compliance engineering work. Air quality engineering is enormous in the Chicago nonattainment area — major stationary sources require complex air quality permits (Title V, NSR) under Illinois's federally approved State Implementation Plan, creating significant technical demand for air quality modeling and compliance engineering.

Illinois environmental engineering careers benefit from one of the nation's most sophisticated regulatory environments — IEPA's programs, particularly TACO for contaminated site cleanup and the Lake Michigan NPDES program, create technical credentials that are recognized across the Midwest and nationally. Chicago's large corporate and consulting market provides career depth and breadth available in few Midwestern cities. Typical Career Trajectory:

• Staff Environmental Engineer (0–3 years): $64,000–$80,000 — Entry-level roles at IEPA, MWRD, consulting firms (AECOM, Arcadis, CDM Smith), or industrial environmental departments. Illinois entry-level environmental engineers often specialize early in LUST/petroleum remediation (the dominant practice) or water quality given the volume of work in each area. TACO certification training is typically completed in the first 1–2 years of practice.
• Project Environmental Engineer (3–6 years): $80,000–$102,000 — Managing SRP cleanup projects or LUST remediation programs. Illinois TACO expertise — the ability to develop risk-based cleanup objectives and remediation completion reports for IEPA review — is the defining technical credential for Illinois environmental engineers in the contaminated site practice area. PE licensure pursued.
• Senior Environmental Engineer (6–12 years): $102,000–$130,000 — Leading major SRP projects, large-scale brownfield remediation programs, or MWRD technical programs. Senior environmental engineers at Chicago's major consulting firms (Arcadis has one of its largest U.S. offices in Chicago) manage multi-million-dollar remediation programs for Fortune 500 industrial clients.
• Principal / Practice Director (12+ years): $130,000–$170,000+ — Consulting firm practice leadership or IEPA division director roles. The most senior positions in Illinois environmental engineering are at the largest Chicago-area consulting firms and at IEPA's central offices in Springfield and Chicago.

Brownfield Redevelopment as Career Differentiator: Chicago's massive brownfield inventory — former steel mills, rail yards, manufacturing plants, and gas stations across the South and West Sides — creates a distinctive environmental engineering career pathway in brownfield redevelopment. Environmental engineers who specialize in IEPA SRP navigation, brownfield grant program management (EPA Brownfields Assessment and Cleanup Grants), and mixed-use development environmental permitting develop a career credential that is highly valued by Chicago's active real estate development and urban planning community.

Illinois's $94,000 average environmental engineering salary is well above the national average and reflects the premium that Chicago's sophisticated regulatory environment, large corporate client base, and high cost of living command. Illinois has a flat 4.95% income tax — moderate nationally. Chicago Metro (Cook and Collar Counties): Illinois's dominant environmental engineering market. Consulting firm and corporate environmental engineering salaries of $92,000–$140,000 for experienced engineers. Cost of living in Chicago is approximately 20–35% above the national average. Median home prices of $280,000–$500,000 in Chicago neighborhoods and collar county suburbs — a wide range reflecting Chicago's geographic diversity. Springfield / Central Illinois: IEPA headquarters and state agency environmental engineering at $68,000–$98,000. Significantly more affordable cost of living than Chicago. Peoria / Quad Cities: Industrial and consulting environmental engineering at $75,000–$108,000 with cost of living below the national average. IEPA Government Salaries: IEPA environmental engineering roles follow state of Illinois pay grades — approximately $62,000–$88,000 for environmental engineers, with senior technical and supervisory roles reaching $88,000–$110,000. Illinois state employees receive access to the Illinois State Employees' Retirement System (SERS) — a defined benefit pension — and comprehensive state health insurance. MWRD Salaries: The Metropolitan Water Reclamation District pays environmental engineers $78,000–$120,000+ for experienced engineers, with strong union-negotiated benefits including defined benefit pension access — one of the better total compensation packages for environmental engineers in the Chicago metro outside major consulting firms.

The Illinois Department of Professional Regulation (IDFPR) administers professional engineering licensure for environmental engineers. Illinois's PE requirements are standard with state-specific regulatory elements that are important for Illinois environmental practice. Illinois PE Licensure Pathway:

• FE Exam: Standard NCEES format. University of Illinois Urbana-Champaign (one of the nation's top engineering schools, with a national reputation in environmental and water resources engineering), Northwestern University, Illinois Institute of Technology (Chicago), and University of Illinois Chicago prepare Illinois's environmental engineering pipeline. UIUC's environmental engineering alumni network is particularly influential in Chicago's consulting market and at IEPA.
• 4 Years of Progressive Experience: Under PE supervision across water quality, contaminated site remediation, and environmental compliance disciplines.
• PE Environmental or Civil Engineering Exam: Standard NCEES exams accepted. Illinois environmental engineers in the dominant contaminated site and water quality practices most commonly pursue the Environmental Engineering PE exam.

Illinois-Specific Regulatory Credentials: TACO (Tiered Approach to Corrective Action Objectives) proficiency — Illinois's risk-based cleanup standard framework is central to LUST and SRP environmental engineering practice. Understanding Tier 1 default cleanup objectives, Tier 2 generic remediation objectives calculated using IEPA's formulas, and Tier 3 site-specific risk assessment approaches is the essential technical foundation for Illinois contaminated site engineering. IEPA SRP Licensed Professional Engineer of Record (LPER) qualification — environmental engineers serving as the PE of Record for SRP projects must understand SRP procedural requirements, No Further Remediation (NFR) letter processes, and institutional controls. Illinois NPDES permit conditions including Great Lakes Water Quality Guidance anti-degradation requirements. Key Professional Certifications: Licensed Environmental Professional (LEP) — Illinois does not have an LEP equivalent, but CHMM is widely held. LSRP (Licensed Site Remediation Professional) — New Jersey's LSRP concept has influenced Illinois policy discussions, though Illinois has not adopted a similar program. Professional Geologist (PG) — dual PE/PG is valued in Illinois's contaminated site practice. Certified Groundwater Professional (CGP) — useful in Illinois's large groundwater monitoring and remediation market.

Illinois's environmental engineering outlook is positive, anchored by the large and long-running LUST remediation program, active brownfield redevelopment, Lake Michigan water quality investment, and emerging PFAS regulatory response. Chicago's active economy provides broad non-cyclical demand for environmental engineering services. PFAS Regulatory Response: Illinois is one of the most proactive states in PFAS regulation — the state has adopted groundwater quality standards for PFOA and PFOS and has an active PFAS investigation program at industrial and military sites. Chicago O'Hare International Airport's PFAS contamination from firefighting foam, multiple Illinois National Guard airfield sites, and industrial PFAS users across the Chicago metro are generating significant new environmental engineering investigation and remediation workscopes. Lake Michigan Shoreline Restoration: The Great Lakes Restoration Initiative (GLRI) — federal funding for Great Lakes water quality improvement — has directed hundreds of millions of dollars to Illinois for shoreline restoration, combined sewer overflow reduction, and tributary sediment remediation. Environmental engineers supporting GLRI-funded projects are in demand at MWRD, IEPA, and the Chicago Department of Environment. Chicago Brownfield Redevelopment: Chicago's urban revitalization — including major projects in the former U.S. Steel South Works area, the Lincoln Yards development site, and numerous former industrial sites on the North Side and Northwest Side — is driving consistent demand for environmental engineering in Phase I/II assessment, SRP-governed cleanup, and brownfield grant program management. Each major Chicago development project requires years of environmental engineering from site acquisition through cleanup completion. Lead Service Line Replacement: Illinois's mandatory lead service line replacement program (one of the nation's most ambitious) requires environmental engineering for service line inventory assessment, replacement prioritization, and water quality monitoring — a new environmental engineering practice area that will sustain employment for years. Workforce Projection: Environmental engineering employment in Illinois is expected to grow 6–9% over the next five years.

Environmental engineering in Illinois is defined by the density of Chicago's industrial legacy — virtually every block of Chicago's former industrial neighborhoods conceals contamination from a century of manufacturing, gas stations, dry cleaners, and rail yards — and by the sophistication of the state's regulatory programs, which demand technical rigor and regulatory fluency from practicing environmental engineers. At a Major Environmental Consulting Firm (Chicago — Loop or Near North Side): A senior environmental engineer on a Monday might start the day preparing for a critical IEPA SRP review meeting — reviewing the draft Remediation Completion Report (RCR) for a former printing facility in the West Loop where chlorinated solvents contaminated the building soil and groundwater. The RCR documents the completion of an in-situ chemical oxidation (ISCO) treatment program and proposes a No Further Remediation (NFR) designation with an institutional control limiting the site to commercial/industrial use. The afternoon involves a site visit to a North Side brownfield where a real estate developer is planning a mixed-use residential project on a former auto body shop — conducting a Phase II ESA and evaluating whether the PCE and petroleum contamination from the site's historical use requires SRP enrollment before the developer can proceed with permits. Before leaving the office, the engineer reviews a TACO Tier 2 analysis prepared by a junior engineer for a LUST site in the western suburbs, checking whether the risk-based soil cleanup objectives are correctly calculated using IEPA's TACO spreadsheet tool. At IEPA (Springfield or Chicago): An IEPA environmental engineer in the Bureau of Land SRP section might spend a morning reviewing a Remedial Action Plan submitted by a consultant for a large industrial Superfund-equivalent site in East St. Louis — evaluating whether the proposed engineered barrier system meets IEPA's technical specifications and whether the institutional controls proposed in the plan are enforceable. Afternoon involves reviewing a LUST Annual Report for a major gas station chain, assessing whether the remediation progress at 20 Illinois sites justifies the proposed natural attenuation monitoring approach. Illinois Lifestyle: Chicago is one of America's genuinely great cities — world-class restaurants, architecture, music, and museums alongside an extensive lakefront park system, professional sports, and some of the most diverse neighborhoods in the nation. Environmental engineers in Chicago consistently rate the city's urban vitality as a major quality-of-life asset, offset partially by Illinois's high property taxes and cold winters that limit outdoor recreation to roughly six months of the year.