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Review government records associated with Grass Valley, California.
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Check your water bill for your utility name and confirm the reporting year. See EPA’s guide to finding your annual water quality report.
Public water-system records for Grass Valley, CA from EPA SDWIS.
City of Grass Valley
Active monitoring or reporting issue detected in EPA SDWIS.
Reviewed: active/open records as of Q1 2026
City listed in EPA records · Serves 4,947 people
Data from EPA SDWIS
Reviewed: source records as of Q1 2026
EPA UCMR5 — No PFAS detection records shown for these water systems
Open data source: EPA UCMR5DoD PFAS — No investigation records shown for this report
Open data source: DoD PFASEPA ATTAINS records identify assessed water bodies that do not meet water-quality standards for designated uses.
Rattlesnake Creek-Wolf Creek
Reported: Nov 2026
Health-relevant causes: Pathogens
Affected uses: Recreation
Data from EPA ATTAINS
NPDES permits regulate pollutant discharges into U.S. waterways. Facilities must report compliance quarterly.
Violation records
Last inspected: Dec 2025
Last inspected: Dec 2025
Data from EPA ECHO
To investigate water contamination, check the sampling locations, dates and results below. For tap water records, see Drinking water quality above.
Reviewed: source records as of 2026
Review historical EPA air pollution records, including monitoring and facility emissions where available. For current conditions, check local air quality on AirNow.
Nevada County
Assessment year: 2020
According to EPA, a cancer risk of 40-in-1-million means that for every 1 million people continuously exposed to these air toxics over a 70-year lifetime, an estimated 40 may develop cancer from that exposure. This is in addition to cancer risk from all other causes.
Top modeled source groups
Data from EPA AirToxScreen
EPA designates an area as nonattainment when air quality does not meet federal health-based standards (NAAQS) for a specific pollutant.
Nevada County (Western part): Ozone
NonattainmentSerious8-Hour Ozone (2015 Standard)
Original designation: Aug 2018
Health effects (EPA): Respiratory inflammation, aggravation of asthma, reduced lung function (EPA)
Data from EPA Green Book
EPA annual monitor summaries describe past measurements. For current air quality, see AirNow.
Auburn-Atwood
Annual mean: 0.042 Parts per million
EPA primary exceedance count: 2 (Ozone 8-hour 2015)
Observation year: 2025
Annual mean: 6.6 Micrograms/cubic meter (LC)
Observation year: 2025
Colfax-City Hall
Annual mean: 0.040 Parts per million
Observation year: 2025
Data from EPA AQS
Reviewed: source records as of Q4 2025
Reviewed: source query run Nov 2026
Brownfield sites are properties where redevelopment is complicated by the presence of hazardous substances.
Open data source: Search EPA ECHO1 site with active cleanup or investigation status
530 Freeman Lane, Grass Valley
Reported: Feb 2026
State environmental agencies maintain cleanup site databases that include state Superfund, voluntary cleanup, and brownfield remediation programs. These programs track additional sites beyond those on the federal NPL.
3 sites with active cleanup or investigation
South of 200 Block of Joyce Drive, Grass Valley
1.2 miles away · NEVADA County
Reported: Nov 2026
South of Dorsey Drive and southeast of Highway 49/20, Grass Valley
0.7 miles away · NEVADA County
Reported: Nov 2026
545 MAIN STREET EAST, GRASS VALLEY
0.2 miles away · NEVADA County
Reported: Nov 2026
Data from EPA ECHO
No release reports shown in this group.
Reviewed: active/open records as of 2018
Data from EPA UST Finder
No MSHA mine or extraction site records shown for this report.
Nevada County, CA
EPA Radon Zone Map (June 2024 release)
Nevada County is EPA Radon Zone 2 (moderate potential). EPA defines Zone 2 counties as having predicted average indoor screening levels between 2 pCi/L and 4 pCi/L.
Radon levels can vary from home to home, so EPA recommends testing the property to know its indoor level.
FEMA flood zones describe mapped flood hazards. Look up a specific address with FEMA.
Special Flood Hazard Area — 1% annual chance of flooding (100-year floodplain) with base flood elevation.
Results use an earlier stored RMP inventory. Current EPA ECHO location coverage is unverified.
EPA ECHO lists facilities linked to the Risk Management Program. Results include facilities with locations that can be matched. Records may be historical. Current operations, chemical inventories, and recent accident history are unverified.
Reviewed: 2000-present
Health outcomes from County Health Rankings. Values shown alongside state and national averages.
Nevada County, CaliforniaPop. 102,293
County Health Rankings edition: 2024
Premature Death
Poor or Fair Health
Poor Physical Health Days
Poor Mental Health Days
Adult Smoking
Adult Obesity
Air Pollution - Particulate Matter
Drinking water violation indicator
Diabetes Prevalence
Life Expectancy
| Indicator | County | State | National |
|---|---|---|---|
| Premature Death | 7,627 | 6,373 | 7,972 |
| Poor or Fair Health | 13.0% | 15.8% | 14.2% |
| Poor Physical Health Days | 3.4 | 3.1 | 3.3 |
| Poor Mental Health Days | 5.5 | 4.7 | 4.8 |
| Adult Smoking | 12.0% | 8.8% | 15.0% |
| Adult Obesity | 27.5% | 27.8% | 34.0% |
| Air Pollution - Particulate Matter | 6.3 | 7.1 | 7.3 |
| Drinking water violation indicator | Yes | N/A | N/A |
| Diabetes Prevalence | 7.8% | 10.8% | 9.6% |
| Life Expectancy | 80.0 | 79.9 | 77.6 |
This report does not have PFAS sample results for the candidate water systems in Grass Valley.
Check with the utility that serves your address for its testing results.
EPA drinking water records on this page list 1 violation for the City of Grass Valley.
Check your water bill to identify the utility serving your address. Ask that utility about current drinking water advisories.
Nearby EPA monitoring stations provide annual air quality measurements for Grass Valley.
The monitoring station at Auburn-Atwood recorded an annual average of 0.042 Parts per million for ozone in 2025.
The monitoring station at Auburn-Atwood recorded an annual average of 6.6 Micrograms/cubic meter (LC) for fine particles (PM2.5) in 2025.
The monitoring station at Colfax-City Hall recorded an annual average of 0.04 Parts per million for ozone in 2025.
The radon data for Grass Valley covers Nevada County. EPA places this area in Zone 2, with a predicted average indoor radon screening level of 2 to 4 picocuries per liter.
No Superfund sites were returned for this city report.
This city report shows 3 brownfield sites: 309 Mill Street; 341 East Main Street; 530 Freeman Lane.
EPA Superfund recordsView on EPA ECHOView on EPA ECHOView on EPA ECHO
The county data for Grass Valley reports a life expectancy of 80.0 years in Nevada County, California.
The figure is from the 2024 edition of County Health Rankings, a University of Wisconsin program that publishes county health statistics.
The county data for Grass Valley reports 7,627 years of life lost to deaths before age 75 per 100,000 residents in Nevada County, California. This measure adds up the years lost to early deaths and adjusts for differences in population age.
The figure is from the 2024 edition of County Health Rankings, a University of Wisconsin program that publishes county health statistics.
The county data for Grass Valley lists fine-particle pollution (PM2.5) at 6.3 micrograms per cubic meter in Nevada County, California.
The figure is from the 2024 edition of County Health Rankings, a University of Wisconsin program that publishes county health statistics.