Contaminant 5000
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2025 (contaminant 5000).
12 TRI facilities inside the city limits and 10 public water systems serving residents. In-city TRI releases fell meaningfully year over year (-22%). Toxic releases concentrations have fallen 50% since 2010.
FIPS 4561405 · population 74,170 · York County
Unresolved Phase I/II/V Inorganic Chemical Rules violation cited in 2025 (contaminant 5000).
Unresolved Phase I/II/V Synthetic Organic Chemical Rules violation cited in 2024 (contaminant 7000).
Phase I/II/V Inorganic Chemical Rules health-based violation cited in 2024 (contaminant 5200).
PM2.5 annual mean (NAAQS 9 µg/m³ (annual)) concentrations have fallen 47% since 2010.
PM2.5 24-hour 98th percentile (NAAQS 35 µg/m³ (24-hour)) concentrations have fallen 50% since 2010.
Ozone 8-hour 4th-highest daily max (NAAQS 0.070 ppm (8-hour)) concentrations have fallen 13% since 2010.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
Single-vintage exposure modeling — EPA cadence is multi-year, so no trend line yet.
TRI air releases (5.1 fugitive + 5.2 stack) concentrations are roughly unchanged from 2010.
TRI water releases (5.3) volumes here are too small to anchor a multi-year trend; YoY movement is still shown above.
TRI land + off-site releases concentrations have more than halved since 2010.
Greenhouse gases (GHGRP large emitters, through 2023) concentrations have fallen 23% since 2010.
| Facility | Top chemical | Total releases | YoY |
|---|---|---|---|
| Cytec Engineered Materials INC.Syensqo Holding INC | Hydrogen cyanideHealth riskAcutely lethal at high doses by blocking cellular respiration; chronic low-dose exposure damages the thyroid and nervous system. (EPA, ATSDR) | 70k lb | -8% |
| Atotech USA LLCAtotech Manufacturing INC | Nitric acidHealth riskStrong corrosive irritant to skin, eyes, and the respiratory tract. (NIOSH) | 53k lb | -34% |
| Pbi Performance Products INCThe Intertech Group | PhenolHealth riskCorrosive on contact; absorbed through skin; high exposure damages kidneys, liver, and the central nervous system. (NIOSH) | 25k lb | -13% |
| Sem Products INCPpg Industries INC | TolueneHealth riskCentral-nervous-system depressant. Chronic high exposure causes hearing loss and developmental effects. (EPA, ATSDR) | 15k lb | -23% |
| HuntsmanHuntsman CORP | TolueneHealth riskCentral-nervous-system depressant. Chronic high exposure causes hearing loss and developmental effects. (EPA, ATSDR) | 3k lb | -55% |
| Inchem CorpInchem Holdings | Xylene (mixed isomers)Health riskEye, skin, and respiratory irritant; central-nervous-system effects from chronic exposure. (EPA) | 2k lb | +37% |
| Possehl Connector Services Sc INC. | Nickel And Nickel CompoundsHealth riskNickel compounds are IARC Group 1 carcinogens; inhalation exposure raises lung and nasal cancer risk. (IARC) | 1k lb | -65% |
| Harrell Industries INC | Formic acid | 421 lb | +30% |
| Koppers Performance Chemicals INCKoppers INC | Copper compoundsHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 25 lb | +67% |
| Pdm US LLC | CopperHealth riskInhaled copper fumes cause metal-fume fever; chronic ingestion above EPA's 1.3 mg/L action level damages the liver. (EPA) | 0 lb | — |
3 unresolved violations on the SDWIS record across utilities serving this city.
Utilities serving
Population served
Health-based · 5yr
Unresolved
| Water system | PWSID | Population served | Health-based · 5yr | Status |
|---|---|---|---|---|
| Adnah Hills Mhp (Sc4660115) Private | SC4660115 | 350 | 1 | UNRESOLVED |
| Duncan Mhp (Sc4660093) Private | SC4660093 | 60 | 1 | Returned to compliance |
Showing the 2 systems with recorded health-based or unresolved violations. 8 additional systems are in compliance with no recorded health-based violations in the past 5 years and are not individually tabulated.
A public water systemis the regulated entity, not the city. EPA's SDWIS definition covers anything serving 25+ people for 60+ days a year or with 15+ service connections — that includes municipal utilities (City of Stockton), water districts, mobile home parks operating their own wells, schools, and small private subdivisions. Each system is independently monitored. Some systems serve multiple cities; some cities are served by many systems.
Sites on EPA's Superfund National Priorities List, plus deleted sites whose cleanup objectives EPA has finalized. Federal-facility sites (defense, DOE, etc.) are flagged separately. Each link routes to a per-site page.
| Site | Status | Federal facility | Primary contaminant |
|---|---|---|---|
| Rock Hill Chemical Co. | NPL FINAL | No | Chloroethene (Vinyl Chloride)Health riskIARC Group 1 carcinogen — angiosarcoma of the liver. Final TCE/PCE biodegradation product; commonly found in groundwater plumes. EPA MCL 2 µg/L. (IARC, EPA) |
Rock Hill, South Carolina (Census place block groups): 74,170 residents. City disparity score for pm2.5 (fine particulate) sits below the reference (54). Why we surface this →
Low-income
People of color
Under age 5
Over age 64
| Indicator | Disparity score | Reading |
|---|---|---|
| PM2.5 (fine particulate) | 54 | below the reference |
| Ozone | 34 | well below the reference |
| Nitrogen dioxide (NO₂) | 64 | below the reference |
| Diesel particulate | 94 | near the reference |
| Toxic releases (RSEI) | 144 | moderately above the reference |
| Traffic proximity | 76 | below the reference |
| Lead-paint risk (pre-1960 housing) | 60 | below the reference |
| Superfund site proximity | 124 | moderately above the reference |
| RMP-facility proximity | 114 | moderately above the reference |
| Hazardous-waste site proximity | 103 | near the reference |
| Underground storage tanks | 136 | moderately above the reference |
| NPDES wastewater proximity | 125 | moderately above the reference |
| Drinking-water non-compliance | 2 | well below the reference |
Source: Census ACS 2018-2022 (5-year) + USEPA-clone EJ blockgroup stats (raw indicators + EJ disparity mirror).
Modeled adult-prevalence estimates published by CDC PLACES, paired with this city's pollution and demographic context. Comparisons are ecological, not causal — pollution and disease prevalence covary at the area level, but the data does not attribute any individual's diagnosis to local exposure. How this section works →
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
CDC PLACES · 2025 release · BRFSS 2022-2023
PLACES uses BRFSS-modeled small-area estimates, not individual records. Crude prevalence shown above is the local rate as published; comparators are age-adjusted vs the South Carolina mean and the US mean — both population-weighted across counties — so geographies with different age structures stay apples-to-apples. Sources: CDC PLACES · 2025 release · BRFSS 2022-2023.
Sources.