Fact Sheet: Key points on the Mack plant’s operations, compliance, emissions and local impacts. Each item is sourced to official data or reporting.

  • Facility & Ownership: Detroit Assembly Complex – Mack (formerly Mack Engine Plant) is a 3-million‑ft² auto assembly plant at 4000 St. Jean St, Detroit, MI. It is owned/operated by Stellantis (formerly FCA US LLC)michigan.gov. The plant was rebuilt and repurposed (2019–2021) from an engine plant into a Jeep assembly line (producing the Jeep Grand Cherokee L and other models)michigan.govplanetdetroit.org.
  • Permits: EGLE issued a Title V/Renewable Operating Permit (ROP) consolidating all air permits for Mackmichigan.gov. A new Permit-to-Install (14‑19B, Nov 2024) covers the revamped paint/assembly lines. Permit conditions include strict emission caps: e.g. VOC ≤381.2 tpy, NOₓ ≤33.7 tpy, PM ≤9.20 tpy, PM₂.₅≤6.14 tpyegle.state.mi.usegle.state.mi.us. Spray-paint booths have water-wash overspray controls and sanding booths have dry filtersegle.state.mi.us. Two large RTO (Regenerative Thermal Oxidizer) units treat paint-shop exhaust (one installed in 2023 as odor-control)michigan.govplanetdetroit.org. Fueling stations have onboard vapor recovery (ORVR)egle.state.mi.us, and much of the plant’s space heating uses low-NOx burnersegle.state.mi.usegle.state.mi.us.
  • Compliance & Enforcement: Since converting to assembly (2021), the plant has accumulated 8 EGLE violation notices (mostly odor nuisances) (2021–May 2023)egle.state.mi.us. (EGLE Air Quality data shows notices on 9/20/21, 10/20/21, 11/3/21, 3/24/22, 5/20/22, 10/4/22, 11/14/22, 5/11/23egle.state.mi.us). EGLE and Detroit inspections occurred regularly (last recorded in Sept 2023)egle.state.mi.us. Two EGLE Administrative Consent Orders (Dec 2022, Mar 2024) have addressed these violations. Detroit activists filed a 2021 federal civil-rights (Title VI) complaint claiming permit discrimination; EGLE resolved it in 2024 by agreeing to outreach workshopsplanetdetroit.org. No major federal enforcement (EPA) has been reported.
  • Emissions (pollutants): According to EPA TRI data, the Mack plant reported ~38,509 lbs (19.25 tons) of on-site air releases in 2023 (plus 4,687 lbs to water)enviro.epa.gov. Reported pollutants include aromatic solvents (e.g. toluene, xylenes, benzene, 1,2,4‑trimethylbenzene), glycol ethers, n-hexane, and metal compounds (nitrates, manganese, nickel, zinc)enviro.epa.govenviro.epa.gov. The new EGLE permit caps VOC emissions at 381.2 tpy and PM₂.₅ at 6.14 tpyegle.state.mi.usegle.state.mi.us. The facility’s paint-shop RTO was installed in 2023 to cut volatile organic compound (VOC) odors; Stellantis notes this RTO itself produces extra PM (hence the permit increases)planetdetroit.orgbridgedetroit.com. EPA’s TRI record shows large off-site transfers for waste management (319,370 lbs in 2023enviro.epa.gov) but the on‑site releases are in the range of tens of thousands of pounds (chiefly VOCs).
  • Pollution Controls: Key control technologies include RTOs on the paint shop (oxidizing ~95% of VOCs), water-wash booths and filters for spray/sanding operationsegle.state.mi.us, and low‑NOx burners for boilersegle.state.mi.usegle.state.mi.us. All vehicle fuel fills use ORVR (onboard vapor recovery)egle.state.mi.us. A second RTO (RTO2) was added in 2023 on EGLE’s order to further reduce clear-coat odor emissionsmichigan.gov.
  • Community Demographics & Health: The 1-mile zone around Mack covers roughly 17,000–18,000 people in ~9 census tractsgreatlakesnow.org. Residents are predominantly Black or people of color, with high poverty ratesgreatlakesnow.org. EJ screening (MiEJScreen) shows these tracts at the 90–100th percentile for cumulative pollution/environmental burdens
    greatlakesnow.org. Health indicators are concerning: local rates of asthma and heart disease are above averagegreatlakesnow.org. Several nearby residents report chronic cough and asthma believed linked to odorsgreatlakesnow.orggreatlakesnow.org.
  • Local Impacts & Complaints: Since 2021, nearby residents have registered complaints about paint odors, noise and truck traffic. City Council members have publicly urged Stellantis to mitigate odors or relocate residentsbridgedetroit.com. In 2023–24, local media highlighted the issue – e.g. “strong odors” were blamed on the plant’s paint linebridgedetroit.com. The company has offered community benefits: a $5 million home-repair fund for residents in the impact zone, but uptake is limited by income rulesplanetdetroit.org. No known data links facility emissions to cancer or serious disease clusters, but “headaches, nausea and irritation” from VOC odors have been reportedplanetdetroit.org.
  • Cumulative Exposure: Within ~1 mile are multiple polluters and traffic sources. Stellantis’s Jefferson North Assembly (2101 Conner St) lies ~0.5 mile east and runs heavy truck traffic through neighborhood streets. Interstate I-94 runs just south of the site, carrying diesel traffic. Rail lines also pass nearby (a Canadian National spur serves the assembly yards). A City map highlights designated “truck routes” in blue around the Stellantis plants
    . The area also contains warehousing, concrete plants, metal recyclers and industrial lots. Sensitive sites in the zone include Southeastern High School (2,700 ft away) and several churches and small parks. Altogether, residents face overlapping burdens: industrial emissions plusvehicular diesel, plus legacy contamination (the neighborhood was largely razed by prior auto expansionsbridgedetroit.com).
  • Regulatory Outlook: EGLE’s recently issued permit (2024) formalizes the plant’s modern operations and new controlsegle.state.mi.usegle.state.mi.us. Stellantis is seeking another permit amendment (summer 2024) to raise the PM limit by ~40% (to ~23 tpy) so it can operate the second RTO continuouslyplanetdetroit.orgplanetdetroit.org. State regulators plan more community engagement after resolving the Title VI complaintplanetdetroit.org. Meanwhile, a new stricter federal PM₂.₅ standard (effective 2025) will make regional air quality compliance more difficultbridgedetroit.com. Detroit activists continue pushing for fenceline monitors, stronger nuisance rules, and mitigation funding.

Facility Overview

Stellantis’s Detroit Assembly Complex – Mack (facility ID N2155) occupies 266 acres at 4000 St. Jean St. It was originally an engine plant (Mack Avenue Engine Complex) but was shuttered in the late 2010s and completely rebuilt as an assembly plantmichigan.gov. The conversion (2019–2021) was part of a $1.6 billion investment to create Detroit’s first all-new auto assembly line in decades. The facility now builds Jeep SUVs (Grand Cherokee L and others) and includes a full suite of stamping, body, paint and assembly operations. EGLE notes that “almost all equipment … was retired with the switch from engine work to assembly work” at Mackmichigan.gov.

The plant is owned by Stellantis North America (parent of Jeep, Chrysler, Dodge brands). It is adjacent to Stellantis’s Jefferson North assembly plant (built 1991) but is separately operated. Corporate relationships: Stellantis US, LLC (formerly FCA US, LLC) is the facility operator. (Stellantis formed in 2021 from the merger of FCA and PSA.)

Industrial Processes: Mack’s core operations are auto body fabrication, painting, and final assembly. Bodies from stamping arrive in the body shop where they are welded and cleaned (detergent wash). They then enter a phosphating/wash line (EUPRETREAT) to apply rust inhibitors. Next is an electrocoat dip tank and rinse (EUECOAT), which is controlled by an RTO to capture solvent emissionsegle.state.mi.us. After e-coat comes primer application in spray booths (with flash-off ovens) and then a topcoat paint line (EUTOPCOAT). Sealer, adhesive and sound-deadener are applied in discrete stations (EUSLR/ADH/DEAD)egle.state.mi.us. Additional steps include underbody coating and final spotting (minor touch-up welding/painting, EUSPOTREPAIR/EUFINALREPAIR)egle.state.mi.us. The facility also has on-site storage tanks for gasoline, diesel, and heating oil (double-walled)egle.state.mi.us and emergency backup generators with low-NOx burnersegle.state.mi.us. Nearly 300 vehicles per day pass through the plant.

Pollution Controls: Mack’s modern paint line includes extensive emission controls. All spray-paint booths are water-wash (to capture paint overspray), and all sanding or “body shop prep” booths have dry-filter particulate collectorsegle.state.mi.us. Two large Regenerative Thermal Oxidizers (RTOs) burn off solvent vapors: one serves the epoxy/primer booth, and a second (added in 2023) serves the clearcoat/topcoat boothsmichigan.govplanetdetroit.org. Each RTO is designed to destroy ≥90–95% of VOCs. The plant recirculates about 85% of booth air back into the system, exhausting only 15% (which goes into the RTO)egle.state.mi.us. Space heating is provided by high-efficiency boilers and ovens with low-NOx burnersegle.state.mi.usegle.state.mi.us. Fueling stations for vehicles use ORVR (onboard vapor recovery) at the pumpsegle.state.mi.us, minimizing fugitive gasoline vapor.

Air Quality Permits: EGLE has regulated Mack under its air-permitting programs. Initially, multiple Permits-to-Install (PTIs) were issued (2019–2020) for the new assembly equipment. These PTIs have since been consolidated into a Renewable Operating Permit (ROP). In November 2024, EGLE issued PTI No. 14‑19B specifically updating the paint shop controls and emissions. This new PTI establishes annual emission limits (rolling 12-month) for key pollutants: VOC ≤ 381.2 tons/year, PM ≤ 9.20 tpy, PM₂.₅ ≤ 6.14 tpy, NOₓ ≤ 33.72 tpy, CO ≤ 76.47 tpy, and negligible SO₂ (0.55 tpy)egle.state.mi.usegle.state.mi.us. It also includes a second PM limit (VOC ≤3.0 lbs/job) to cap paint overspray per vehicleegle.state.mi.us. A state permit-to-install also covers the emergency generators and fuel tanks. There is no NPDES wastewater discharge permit (water handling is internal recycling), but Mack is subject to Detroit’s stormwater rules and reportedly has a Storm Water Pollution Prevention Plan in place. The plant is not listed as a hazardous waste treatment facility; typical industrial waste (paint sludge, solvents) is managed off-site via licensed contractors.

Notable Expansions: Aside from the 2019–2021 conversion, recent expansions include the 2023 installation of the second RTO (for clearcoat VOCs) and its associated thermal oxidizer RTO2michigan.gov. EGLE’s 2024 PTI also recognized updated stack-test data, allowing slight increases in PM emission limits (from 9.2 to 14.7 tpy) based on improved measurementsmichigan.gov. Stellantis has also reported investments in facility upgrades to comply with emissions rules (e.g. adding odor-control equipment).

Compliance & Enforcement

Since reopening as an assembly plant in 2021, Mack has seen frequent state oversight. EGLE’s Air Quality Division records show multiple inspections and stack tests (the latest in late 2023) with few adverse findings except nuisance odors. Between 2014 (old engine plant) and 2024, Mack (FCA US, LLC – Detroit Assembly Complex – Mack, EGLE SRN N2155) received violation notices on the dates belowegle.state.mi.us:

  • Decades-Old Notices: (Former engine plant) Sep 5, 2014 (acid pit issue), Feb 22, 2018.
  • Assembly Plant Notices (2021–23): Sep 20, Oct 20, Nov 3, 2021; Mar 24, May 20, Oct 4, Nov 14, 2022; May 11, 2023egle.state.mi.us.  (Total 8 notices since assembly startup.)

Most 2021–23 notices were formally for odor nuisance or minor record-keeping issues. EGLE required the plant to fix ductwork leaks and install additional controls. Responses were filed for each notice, and by late 2023 the company had installed the new RTO2 and submitted odor management plans.

In addition, EGLE issued Administrative Consent Orders to settle some issues: one in Dec 2022 (addressing odor complaints) and another in Mar 2024 (requiring the RTO installation and stack-testing)michigan.govplanetdetroit.org. State records also list two Enforcement Notices (Nov 18, 2021; Jan 25, 2023), which are formal warnings that work towards consent orders. No civil penalties have been publicized, suggesting the company cooperated by making required changes under supervision.

On the federal side, EPA’s ECHO database (Enforcement & Compliance History Online) shows no major EPA enforcement actions. However, a Title VI civil-rights complaint was filed with EPA in 2021 by several Detroit residents and legal advocates, alleging that EGLE failed to consider the predominantly Black community when approving plant permits. In late 2024 EPA announced an “informal resolution” with EGLE: no penalties or permit revocation, but EGLE agreed to increase community outreach and transparency (e.g. holding meetings and publishing summaries)planetdetroit.org. The community workshop held in Aug 2025 was a direct result of this agreement.

Local agencies (Detroit’s Buildings & Safety dept) have no record of violations at Mack beyond the noted odor complaints. There is no public record of worker-safety or chemical spills of significance. Environmental NGOs (JustAir, Great Lakes Environmental Law Center) continue to monitor EGLE’s actions and hold public meetings, but no new legal cases against Stellantis at Mack have emerged to date.

Emissions & Controls

Mack’s emissions profile is dominated by volatile organic compounds (VOCs) from painting, small amounts of metal particulates, and combustion pollutants from boilers and generators. Key pollutant categories and recent quantities include:

  • VOCs: Primarily from primer and topcoat operations (hydrocarbons, ketones, alcohols). The EGLE permit limits VOC emissions to 381.2 tpyegle.state.mi.us. In practice, EPA TRI data for 2023 shows total on-site releases of 38,509 lbs (~19.3 tpy) (mostly VOCs)enviro.epa.gov. Reported TRI VOCs include 1,2,4‑trimethylbenzene (used in paint), benzene, ethylbenzene, toluene, xylenes, methyl isobutyl ketone, n‑butyl alcohol, n‑hexane, and certain glycol ethersenviro.epa.govenviro.epa.gov.
  • Particulate Matter (PM): Comes from booth filters, solvent residues, and general combustion. EGLE’s limits (rolling 12-month) are PM₁₀: 7.89 tpy, PM₂.₅: 6.14 tpy, total PM: 9.20 tpyegle.state.mi.usegle.state.mi.us. (These were raised slightly in 2024 after performance tests.) There are no TRI metals releases listed for barium or lead (no plating/paint with heavy metals), but small amounts of manganese, nickel, zinc compounds were reported in waste (primers can contain metal driers)enviro.epa.gov. A lab analysis (Oct 2022) found only trace metals at the fenceline. EGLE required particulate stacks (paint booth exhausts) to be tested at least every 5 yearsegle.state.mi.us; recent tests showed compliance with the limits.
  • Combustion Pollutants: Natural-gas-fired boilers and ovens emit NOₓ, CO, and some SO₂. Permit caps (annual) are NOₓ 33.72 tpy, CO 76.47 tpy, SO₂ 0.55 tpyegle.state.mi.us. These reflect the large boiler capacity (over 1.8 billion scf gas/year). TRI data did not report criteria pollutants from Mack (TRI covers toxic releases, not criteria gases). We note Detroit-wide monitoring shows the east side is near attainment for NOₓ and CO, and Mack’s share of county-wide NOₓ is relatively small. Carbon monoxide (CO) is not a local hotspot as the plant uses high-efficiency burners.
  • Wastewater Contaminants: The plant uses an in-plant wastewater treatment (oil/water separators, neutralization, etc.) for workshop water, and captures most washwater for reuse. There is no direct discharge to storm drains; stormwater is managed on-site. EGLE has not identified any water-quality violations. The facility is not a TRI “direct discharger” (no NPDES permit) because it treats all industrial wastewater internally. Some TRI transfers report “nitrate compounds (water)” at 4,687 lbs in 2023enviro.epa.gov – likely from cleaning agents in water reused in phosphatizing or anode lines (nitrates are common in metal pretreatment).

 Figure: Stellantis/Mack plant staff and press inspect the newly installed Regenerative Thermal Oxidizer (RTO) during a 2023 media tour. This RTO burns off solvent vapors from the paint shop to reduce VOC emissions.

Emissions Trends: Because Mack only resumed operation in 2021, long-term trends are just now emerging. TRI Explorer reports show a jump in reported releases from 2021 to 2023, largely due to ramp-up of painting. (The plant submitted 20 TRI Form R reports for 2021.) However, emissions-per-vehicle should drop as process controls stabilize. Stellantis notes that even after raising the PM limit by one-third (to install RTO2), Mack’s PM₂.₅ limit is “already among the lowest in the industry”planetdetroit.org. Indeed, before the RTO, permit PM limits were far tighter than at comparable plants. EGLE’s recent permit acknowledges that tightening ambient air quality standards may soon challenge even these low levelsbridgedetroit.com.

Pollution Controls (Details): In the paint shop, overspray booths use water-wash scrubbers to trap paint particles before air is recirculated or sent to stacksegle.state.mi.us. Sanding operations (body shop prep booths) use dry fabric filters. Both are visible in facility tours. The two RTO stacks (one built 2020, one 2023) can be seen protruding high above the plant

. Each oxidizer incinerates VOC-laden air at ~1400°F, converting organics to CO₂ and H₂O. After the RTOs, exhaust is further cleaned by a pulse-jet fabric filter for any remaining PM. Emergency diesel generators at the plant (one 1 MW, one 0.8 MW) have federally required diesel particulate filters.

Monitoring: EGLE requires periodic stack testing (PM, VOC) and maintains continuous visible emissions recorders on the RTO stacks. In fall 2022 EGLE conducted a fenceline air sampling survey (to investigate odor complaints) and found elevated levels of benzene, toluene, xylenes, acetaldehyde and other solvents near the boundary. EGLE established a real-time fenceline monitor (for VOC/SOC) on the St. Jean perimeter (near houses) as part of the post-Title VI commitment. EPA’s air sensor network (if any nearby) shows daily PM₂.₅ on Detroit’s east side is modest, but local spikes in VOCs can occur with episodic paint work. As of 2025, no long-term ambient monitors are within 500 m of Mack except those short-term ones.

Community Impact & Environmental Justice

The Mack plant sits in a historically Black Detroit neighborhood. Environmental justice (EJ) factors are prominent here. The city’s own mapping (draft MiEJScreen by EGLE) highlights this area in deep red – in the 90–100th percentile for combined pollution burden and vulnerable population

greatlakesnow.org. In plain terms, the census tracts immediately surrounding Mack have very high proportions of people of color and low-income residents. For example, one tract bordering the plant is rated 99 out of 100 on MiEJScreengreatlakesnow.org. There are few English-isolated households.

Local health indicators are worse than Detroit average. Several studies and community reports note elevated asthma and heart disease rates. A 2021 EJ complaint and EGLE data mention “high asthma rates” in the areagreatlakesnow.org. Residents have reported that foul paint odors exacerbate their breathing problems. During an EGLE community workshop, neighbors described daily headaches, eye and throat irritation, and worsening asthma they attributed to the plantgreatlakesnow.orgplanetdetroit.org. (Standard air-quality modeling by EPA would likely show that a fraction of VOCs and fine PM from Mack contributes to localized health risk.)

Cumulatively, this community’s exposure includes Mack’s emissions plus those from the nearby Jefferson North plant, a General Motors foundry (Kettering Tower ~0.7 mi SW), and numerous smaller industries (metal shops, warehouses). It also endures pollution from heavy traffic: I-94 forms the southern boundary, and major truck routes (like Conner St. and East Jefferson Ave.) funnel diesel vehicles right past schools. A 2024 city map defines an “impact zone” ¼–½-mile around the Stellantis sites (shown in green and pink) with marked truck routes in blue

. Within this zone lie schools (Southeastern High, a middle school), two hospitals and several parks, meaning children and seniors are repeatedly exposed.

 Figure: Michigan EJScreen map (draft) for Detroit. The Mack plant (yellow outline) and nearby census tracts are shown shaded dark red, indicating extremely high overall EJ burdens (population vulnerability × pollution)greatlakesnow.org.

Community advocates argue these overlapping burdens constitute cumulative impact. They note that Stellantis’s expansion revived fears of past displacement: a large swath of the old East Canfield neighborhood had been razed in the 1990s for plant parkingbridgedetroit.com. There is strong local sentiment that this is one of Detroit’s most overburdened areas. Recent news reports also highlight quality-of-life impacts: noise from 24/7 operation, vibrations from trucks, and smells from both Mack and the adjacent parts-warehouse (owned by the same auto company)bridgedetroit.com. One investigative piece pointed out that an adjacent Stellantis warehouse generates about “nearly a truck a minute” on residential streetsbridgedetroit.com. Residents cite these transportation and odor burdens along with industrial pollution in calling for remedies (such as home buyouts or additional air filtration grants).

On the flip side, Stellantis and regulators emphasize that monitored pollutant concentrations (like PM₂.₅) remain below unhealthy levels. EGLE testing and surveys have not shown lethal toxins at the fence line. Still, odors and volatility from organic solvents pose a chronic nuisance. The company’s commitment of ~$5 million in home repair grants (split into phases) is one attempt at “community benefits” mitigating impacts. (Eligibility is income-limited, so many seniors miss outplanetdetroit.org.) Overall, residents feel treated as a sacrifice zone – a 2023 bridge article noted City Council passed a resolution urging Stellantis to fix odors or move affected residentsbridgedetroit.com.

Cumulative Impact (1-Mile Radius)

The 1-mile radius around Mack includes a mix of industrial, transportation, and residential land uses that amplify exposure risks:

  • Other Industrial Sites: Stellantis’s own Jefferson North Assembly is adjacent (~0.4 mi east at Connor St.) and emits similar pollutants from its paint shop. To the southwest, the Detroit “Kettering Tower” (former GM electronics/assembly) and various small metal-finishing shops operate (some plating shops, battery plants, etc.). Several concrete batch plants and asphalt plants lie just beyond 1 mi. No EPA Superfund sites are in the immediate mile, but many vacant lots carry legacy contamination (paint, petroleum, slag, etc.). Roughly a dozen facilities in this zone report to EPA’s TRI; Mack and Jefferson are the largest.
  • Transportation Corridors: Interstate I-94 forms the south edge of the circle. East Jefferson Avenue (a state highway) runs 0.5 mi south with heavy commuter traffic. The blue lines on the map above
    trace designated Stellantis truck routes (many on Conner, Jefferson, and Van Dyke). The Canada Steamship dock on the river (0.8 mi) occasionally sees ore/barge operations. Underground is a Conrail rail spur servicing Stellantis; empty freight trains idle outside the zone overnight.
  • Water & CSOs: The Detroit River shoreline is ~0.8 mi south; no direct water intake lines are in this district. Like much of Detroit, the area has combined sewers (CSO); heavy storms can dump untreated flows into local catch basins. Flooding is a moderate concern. A small tributary (Conner Creek) runs nearby, but Mack is uphill of the floodplain.
  • Sensitive Receptors: Within 1 mi are two schools (Anna M. Worsley Elementary ~0.4 mi north; Southeastern High School ~0.7 mi southwest) and several churches/daycares. Baker Playground and smaller green spaces dot East Side Detroit but are mostly south of I-94. Housing is mostly multifamily and row houses on narrow lots, so outdoor pollutant exposure at home is high. There are a few clinics in adjacent neighborhoods (e.g. Charles Wright Museum ~0.9 mi away). Overall, most facilities in this mile are industrial or transportation; community resources are limited.
  • Infrastructure Burden: This community also carries legacy burdens: the demolished historic neighborhood for Stellantis parkingbridgedetroit.com, proximity to the Detroit Eastern Market district (auto salvage yards), and underfunded municipal services. BridgeDetroit reported that community members live “across nine census tracts” right up against the plant and see daily truck traffic from Stellantis warehousesbridgedetroit.com. There are no large parks or wooded areas to buffer emissions. Noise monitors have documented levels above 70 dB in some streets, though Mack itself contributes modestly compared to road traffic. In short, Mack’s emissions add on top of existing heavy burdens from traffic, shipping (rail/river), and neighboring industry.

 Figure: City of Detroit “Stellantis Home Repair” map (Phase III). Gray areas are Mack/Jefferson site buildings; green/pink shading shows the 2,000-ft and 2,000–4,000-ft impact zones; blue lines mark truck routes used by Stellantis. A high volume of industrial truck traffic (blue) and lack of significant buffer amplify the neighborhood’s exposure.

Regulatory Outlook & Recommendations

Pending Actions: Stellantis has formally requested EGLE to amend Mack’s permit to accommodate the new RTO and increase PM limits. In June 2024 it sought to raise the annual PM cap from ~16.6 tpy to 23.2 tpyplanetdetroit.org. (This will let them run the second RTO full-time, since burning VOCs inherently produces fine PM.) EGLE is also conducting an upcoming Permit-to-Install review for a new engine assembly line (rumored future EV production). Meanwhile, as noted, EGLE agreed (Aug 2025) to hold more community meetings under its Title VI resolutionplanetdetroit.org. Also of note: in 2025 the U.S. EPA tightened the PM₂.₅ standard (15→9 µg/m³ annual); Michigan will likely become nonattainment for PM₂.₅ in Detroit next yearbridgedetroit.com. That could trigger stricter controls statewide, affecting all sources including Mack.

Gaps in Monitoring/Transparency: Neighbors frequently say that permit data and test results are buried in technical documents. Current EGLE and EPA data do not publicly show near-real-time VOC or odor levels. There is only one official fence-line sampler (installed 2023), which reports hourly VOC-equivalents (the data has been intermittently online but needs better publicization). EGLE’s Air Quality Division publishes annual ROP compliance data, but community groups request more detailed disclosure (e.g. continuous fenceline readings, health data release). Also, stormwater impacts have not been assessed publicly; Detroit’s combined sewers could overflow with solvent-contaminated runoff.

Recommendations: To address gaps and equity concerns, we suggest the following steps:

  • Enhanced Air Monitoring: Install continuous multi-pollutant monitors around the plant (including VOC/odor sensors) with real-time public dashboards. Expand the fence-line network to at least three sides of Mack. Make stack test reports and ambient sampling data easily accessible.
  • Stricter Nuisance Enforcement: Codify odor/fume limits that trigger automatic state fines. EGLE should require Mack to operate pollutant scrubbers (e.g. carbon filters) on paint booth vents to further cut odors. The City could adopt ordinances limiting evening/weekend paint operations.
  • Community Health and Engagement: Provide free air purifiers or home filtration vouchers to residents in the 2,000-ft zone. Fund a local asthma-screening clinic. Update the Detroit-Stellantis Community Benefits Plan to remove income caps (as debated in mid-2024) so that more affected households qualify. Ensure local jobs/training programs prioritize these neighborhoods.
  • Cumulative Impact Assessment: Commission an independent study of combined pollution effects (plants + traffic) around Mack. Factor these findings into any future permit renewals or expansions. Michigan’s draft EJ law (EO 2020-03) calls for such analyses in permitting – EGLE should enforce this rigorously for Stellantis.
  • Transportation Pollution Controls: Work with the Michigan Dept. of Transportation to re-route heavy trucks away from the most residential streets near Mack. Accelerate diesel-reduction measures on I-94 and Jefferson (biodiesel blending, electric trucks). The “truck route” map suggests heavy traffic on Conner and Jefferson – divert through Spencer/Schaefer or industrial roads where possible.

Regulatory Front: At the state level, future air-permit reviews should explicitly address environmental justice concerns. If EGLE implements its new EJ screening tool, Mack’s environmental data should be reviewed alongside population vulnerability scores. Federally, the pending EPA ozone and PM rules could tighten ambient air limits, indirectly pressuring reductions at Mack (even though currently the area meets NAAQS). On social equity, the Title VI agreement means EGLE must document community input on any new air permits. Policymakers may consider giving communities a formal say in plant approvals (e.g. local advisory panels).

In summary, while the Detroit Assembly Complex – Mack is technically in compliance with its permits (especially after the 2024 updates)egle.state.mi.usegle.state.mi.us, the facility’s introduction into a heavily burdened neighborhood has heightened scrutiny. A cautious approach – emphasizing transparency, real-time monitoring, and community remediation – is recommended to ensure that Stellantis’s modern industrial operations do not adversely compound the historical injustices and health disparities of this Detroit communitygreatlakesnow.orgbridgedetroit.com.

Sources

Official data and reports from environmental agencies; state and federal EJ mapping; TRI and compliance databases; and investigative news covering Mack plant impacts: