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Rock County, Wisconsin: environmental and disease records

Cancer mortality in Rock County is 159.7 deaths per 100,000 people per year against a U.S. rate of 143.2, a statistically significant excess. The strongest disease signals are Leukemia deaths at 1.5 times the U.S. rate and Pancreas deaths at 1.2 times the U.S. rate. Federal databases place 725 regulated facilities, sites and hazards inside the county, led by Rail grade crossing (254), NPDES wastewater discharge permit (215), Gas station (mapped facility) (78). EPA AirToxScreen estimates a lifetime cancer risk from outdoor air toxics of 30 in a million, driven mainly by formaldehyde.

Rates are age-adjusted per 100,000 people. A cancer signal is marked significant when the lower bound of its 95 percent confidence interval is above the U.S. rate. Facility counts use active federal records located inside the county boundary. Approximate county center: 42.6699, -89.072.

How this county ranks in Wisconsin

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Cancer deaths and new cases versus the United States

Source: NCI and CDC State Cancer Profiles, both sexes, all ages. Sorted by the ratio of the county rate to the U.S. rate.

Cancer rates for Rock County compared with the United States
Cancer	Measure	County rate	U.S. rate	Times U.S.	95% interval	Years
Leukemia	Deaths	8.3	5.7	1.46xSignificant	6.6 to 10.3	2020-2024
Kidney & renal pelvis	New cases	25.1	17.9	1.4xSignificant	22.1 to 28.4	2019-2023
Leukemia	New cases	18.8	14.5	1.3xSignificant	16.2 to 21.7	2019-2023
Lung & bronchus	New cases	66.5	51.8	1.28xSignificant	61.7 to 71.6	2019-2023
Kidney & renal pelvis	Deaths	4.3	3.4	1.26x	3.1 to 5.8	2020-2024
Bladder	New cases	23.5	18.7	1.26xSignificant	20.6 to 26.6	2019-2023
Pancreas	Deaths	14	11.3	1.24xSignificant	11.8 to 16.5	2020-2024
Non-Hodgkin lymphoma	Deaths	5.9	4.8	1.23x	4.5 to 7.6	2020-2024
Lung & bronchus	Deaths	36.4	30.2	1.21xSignificant	32.9 to 40.2	2020-2024
Melanoma of the skin	New cases	28.5	23.8	1.2xSignificant	25.2 to 32.2	2019-2023
Non-Hodgkin lymphoma	New cases	21.1	18.5	1.14x	18.4 to 24.2	2019-2023
Liver & bile duct	New cases	9.8	8.7	1.13x	8 to 11.9	2019-2023
All cancer	New cases	508.4	453.4	1.12xSignificant	494.5 to 522.7	2019-2023
All cancer	Deaths	159.7	143.2	1.12xSignificant	152.1 to 167.6	2020-2024
Liver & bile duct	Deaths	7.3	6.6	1.11x	5.7 to 9.2	2020-2024
Pancreas	New cases	15.2	13.9	1.09x	12.9 to 17.8	2019-2023
Brain & nervous system	New cases	6.7	6.2	1.08x	5.1 to 8.7	2019-2023
Thyroid	New cases	13.4	13	1.03x	11 to 16.2	2019-2023
Stomach	Deaths	2.6	2.7	0.96x	1.7 to 3.8	2020-2024
Bladder	Deaths	3.8	4.1	0.93x	2.7 to 5.3	2020-2024
Childhood cancer (under 15)	New cases	15.2	16.4	0.93x	9.6 to 22.8	2019-2023
Esophagus	New cases	4.2	4.6	0.91x	3 to 5.6	2019-2023
Stomach	New cases	5.7	6.6	0.86x	4.3 to 7.4	2019-2023
Brain & nervous system	Deaths	3.7	4.4	0.84x	2.5 to 5.1	2020-2024
Melanoma of the skin	Deaths	1.6	2	0.8x	1 to 2.6	2020-2024
Esophagus	Deaths	2.8	3.7	0.76x	1.9 to 4	2020-2024

Mortality measures versus the U.S. county median

Source: County Health Rankings, built from CDC National Vital Statistics System death records. The comparison value is the median of all U.S. counties.

Mortality measures for Rock County
Measure	County	U.S. median	Difference	Unit
Premature death	8,626.2	9,842.6	-12%	years of life lost before age 75 per 100,000
Life expectancy	76.3	75.3	+1%	years
Child mortality	57.3	59.8	-4%	deaths under age 18 per 100,000
Infant mortality	5.7	6.2	-9%	deaths under age 1 per 1,000 live births
Injury deaths	128.4	96.9	+32%	deaths per 100,000
Drug overdose deaths	42.9	28.6	+50%	deaths per 100,000

Air toxics and air quality

EPA AirToxScreen 2020

Lifetime cancer risk from outdoor air toxics: 30 in a million. EPA treats 100 in a million as the upper end of acceptable risk and 1 in a million as the goal.

Formaldehyde15.27 per million
Carbon Tetrachloride2.96 per million
Acetaldehyde1.44 per million
Naphthalene1.23 per million

EPA Air Quality Index 2025

Monitored on 199 days: 159 good, 1 unhealthy for sensitive groups or worse. Median AQI 42, peak 108.

Regulated facilities, sites and hazards by type

725 active records inside the county from EPA ECHO, TRI, Superfund, Brownfields, NPDES, EIA, FAA, FRA and corrections data.

Rail grade crossing254
NPDES wastewater discharge permit215
Gas station (mapped facility)78
Toxic chemical release facility (TRI)27
Auto repair or body shop (mapped facility)25
TRI reporting facility23
Air permit holder (minor source)21
Brownfield property17
Small hazardous waste generator16
Major air pollution source7
Large hazardous waste generator7
Heliport6
Public airport5
Hazardous waste transporter5
Scrapyard (mapped facility)4
Large greenhouse gas emitter3
Gas power plant3
Superfund (NPL) site2
EPA air quality monitor1
Airfield1
Commercial airport1
Dry cleaner (mapped facility)1
Biomass power plant1
Oil-fired power plant1
Solar power plant1

Highest-severity records

The 25 records with the highest Envyrofax severity in the county, with the agency identifier to cite in a records request.

Janesville Ash Beds, Janesville
Superfund (NPL) site. Hazard Ranking System score 57.9. NPL Site.
EPA site ID WID000712950 (U.S. EPA Superfund (SEMS/NPL)) Agency record
Severity 10
Janesville Old Landfill, Janesville
Superfund (NPL) site. Hazard Ranking System score 57.9. NPL Site.
EPA site ID WID980614044 (U.S. EPA Superfund (SEMS/NPL)) Agency record
Severity 10
Rathgibson Janesville Llc, Janesville
TRI reporting facility. Penalties $300,712.
EPA FRS registry ID 110000419725 (U.S. EPA ECHO) Agency record
Severity 8.7
United Ethanol Llc, Milton
Toxic chemical release facility (TRI). Chemicals: Formic acid, Acetaldehyde, Methanol. Reports carcinogens. 86,501 lbs released over 5 years.
TRI facility ID 53563NTDTH125CH (U.S. EPA Toxics Release Inventory)
Severity 8.3
Evonik Corp, Milton
Toxic chemical release facility (TRI). Chemicals: Chloromethane, Ammonia, Acrylonitrile, Ethylene oxide and 4 more. Reports carcinogens. 33,977 lbs released over 5 years.
TRI facility ID 53563XXNCH1012T (U.S. EPA Toxics Release Inventory)
Severity 8
Evonik Industries, Janesville
Toxic chemical release facility (TRI). Chemicals: Chloromethane, Ethylene oxide, Benzyl chloride, Dimethyl sulfate and 4 more. Reports carcinogens. 10,941 lbs released over 5 years.
TRI facility ID 53545SHRXC2001A (U.S. EPA Toxics Release Inventory)
Severity 7.6
Charter Next Generation - Milton, Milton
Toxic chemical release facility (TRI). Chemicals: Ozone. 844,115 lbs released over 5 years.
TRI facility ID 5356WCHRTR1264E (U.S. EPA Toxics Release Inventory)
Severity 7.5
Evonik Industries, Janesville
TRI reporting facility. Penalties $80,000.
EPA FRS registry ID 110022448476 (U.S. EPA ECHO) Agency record
Severity 7.2
Iki Mfg Co Inc, Edgerton
Large hazardous waste generator. Penalties $2,000.
EPA FRS registry ID 110000419627 (U.S. EPA ECHO) Agency record
Severity 7
Rathgibson Janesville Llc, Janesville
Large hazardous waste generator. Penalties $300,712.
EPA FRS registry ID 110000419725 (U.S. EPA ECHO) Agency record
Severity 7
Baker Manufacturing Co, Evansville
Toxic chemical release facility (TRI). Chemicals: Manganese, Copper, Nickel. Reports carcinogens. 1,685 lbs released over 5 years.
TRI facility ID 53536BKRMN133EN (U.S. EPA Toxics Release Inventory)
Severity 7
I-K-I Manufacturing Co I Nc, Edgerton
Toxic chemical release facility (TRI). Chemicals: Xylene (mixed isomers), Propylene, Ethylbenzene, Methyl tert-butyl ether. Reports carcinogens. 1,060 lbs released over 5 years.
TRI facility ID 53534KMNFC107MA (U.S. EPA Toxics Release Inventory)
Severity 6.8
Twin State Inc, Janesville
Toxic chemical release facility (TRI). Chemicals: Ammonia, Zinc compounds. 46,290 lbs released over 5 years.
TRI facility ID 53545TWNST3631P (U.S. EPA Toxics Release Inventory)
Severity 6.6
D & K Coating Technologies Inc, Janesville
Toxic chemical release facility (TRI). Chemicals: Toluene, n-Hexane. 42,245 lbs released over 5 years.
TRI facility ID 53546DKCTN14VEN (U.S. EPA Toxics Release Inventory)
Severity 6.6
Charter Next Generation - Milton, Milton
TRI reporting facility.
EPA FRS registry ID 110071956477 (U.S. EPA ECHO) Agency record
Severity 6.4
Rathgibson Janesville Llc, Janesville
Toxic chemical release facility (TRI). Chemicals: Chromium, Nickel, Manganese, Cobalt. Reports carcinogens. 222 lbs released over 5 years.
TRI facility ID 53545RTHMF2505F (U.S. EPA Toxics Release Inventory)
Severity 6.3
Scot Forge Co, Clinton
Toxic chemical release facility (TRI). Chemicals: Nickel, Chromium, Manganese, Copper and 1 more. Reports carcinogens. 201 lbs released over 5 years.
TRI facility ID 53525SCTFR105SC (U.S. EPA Toxics Release Inventory)
Severity 6.3
Hormel Foods Corp, Beloit
Toxic chemical release facility (TRI). Chemicals: Ammonia, Nitric acid, Chlorine. 13,897 lbs released over 5 years.
TRI facility ID 53511GHRML3000K (U.S. EPA Toxics Release Inventory)
Severity 6.2
Bluescope Buildings Na, Evansville
Toxic chemical release facility (TRI). Chemicals: Manganese, Chromium, Nickel, Copper and 1 more. Reports carcinogens. 105 lbs released over 5 years.
TRI facility ID 53536VRCPR273WA (U.S. EPA Toxics Release Inventory)
Severity 6.1
Frito-Lay Inc, Beloit
Toxic chemical release facility (TRI). Chemicals: Polycyclic aromatic compounds, Nitrate compounds (water dissociable; reportable only when in aqueous solution), Nitric acid, Peracetic acid. Reports carcinogens. 101 lbs released over 5 years.
TRI facility ID 53511FRTLY2810K (U.S. EPA Toxics Release Inventory)
Severity 6
United Ethanol, Llc, Milton
TRI reporting facility.
EPA FRS registry ID 110023153969 (U.S. EPA ECHO) Agency record
Severity 6
Tomah Products, Incorporated, Milton
TRI reporting facility.
EPA FRS registry ID 110000419903 (U.S. EPA ECHO) Agency record
Severity 6
Stainless Tank & Equipment Co Llc, Beloit
Toxic chemical release facility (TRI). Chemicals: Chromium and Chromium Compounds(except for chromite ore mined in the Transvaal Region), Nickel And Nickel Compounds, Manganese And Manganese Compounds, Manganese compounds and 1 more. Reports carcinogens. 75 lbs released over 5 years.
TRI facility ID 53511STNLS81FUR (U.S. EPA Toxics Release Inventory)
Severity 5.9
D&K Coating Technologies, Janesville
TRI reporting facility.
EPA FRS registry ID 110002373039 (U.S. EPA ECHO) Agency record
Severity 5.9
Genencor International Wisconsin Inc., Beloit
Toxic chemical release facility (TRI). Chemicals: Ammonia. 4,560 lbs released over 5 years.
TRI facility ID 53511NZYMB2600K (U.S. EPA Toxics Release Inventory)
Severity 5.8

Correctional facilities

Prisons, jails and corrections operations with an EPA facility record, and the drinking water and wastewater compliance attached to them.

No correctional facility with an EPA record is located in this county.

Discovery / public records

Records to request for Rock County

Wisconsin state cancer registry
Cancer incidence counts by census tract or ZIP code, by cancer type and year (de-identified). Any cancer cluster inquiries or investigations in Rock County, and their findings.
Wisconsin vital statistics office
Death certificate counts by cause of death and residence tract or ZIP code, and the years behind the mortality measures above.
Wisconsin health department, environmental epidemiology
Health consultations or assessments by ATSDR or the state health department covering the county, and any exposure investigations.
Wisconsin environmental agency and the U.S. EPA regional office
Compliance history, inspection reports, notices of violation, penalties and enforcement actions for each facility above, cited by EPA FRS registry ID.
Wisconsin drinking water program
Violation notices, sampling results and sanitary surveys for the public water systems serving the county, including any system serving a correctional facility.
Department of corrections or county sheriff
Water testing, grievances and environmental health inspections for the correctional facilities listed above.

Each Envyrofax address report includes a printable records request worksheet with the custodian and the exact request wording per finding.

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