Empire Mine State Historic Park
Active WDID 5S29I019611 Grass Valley, Nevada County Region 5S · Central Valley (Sacramento)
Watershed, receiving-water, nearby-water and TMDL information is temporarily unavailable. Permit and monitoring records below are complete.
At a glance
- Permit Evidence: SMARTS record
- Active Industrial
- Notice of Intent (WDID code I) · Permits and applications
- Location Evidence: facility-reported
- Grass Valley, Nevada County
- Region 5S · Central Valley (Sacramento) · Location · Statewide map
- Receiving water
- Little Wolf Creek (as reported by the facility)
- Evidence: identification unavailable Details
- Identified receiving water on the 2026 303(d) list
- Not established
- Shown only when the reported receiving water is identified and corroborated.
- 2026 Integrated Report waters within 1.0 km Evidence: geographic proximity
- Evidence: unavailable
- Monitoring results Evidence: facility-reported
- 3,013 distinct results, 11 reporting years (2015 to 2025)
- Most recent sample Feb 16, 2026 · Monitoring
- Compliance and enforcement records Evidence: SMARTS record
- 2 inspections · 3 violation records · 3 enforcement actions
- Counts as published in SMARTS; not a compliance determination · Details
Each label shows where a statement comes from. How to read the labels.
Overview and location
Reported facility location HUC12 watershed Corroborated receiving water 2026 Integrated Report waterbodies nearby
Reported location Evidence: facility-reported
39.207761, -121.043585
Coordinates as reported in the permit application; not a discharge point.
- Facility address
- 10556 E Empire St, Grass Valley 95945
- Regional Water Board
- 5S — Central Valley (Sacramento)
HUC12 watershed Evidence: spatial
Unavailable.
Permits and applications Evidence: SMARTS record
Current permit record
- Permit type
- Industrial
- Application type
- Notice of Intent (WDID code I)
- Status
- Active
- Operator
- California State Parks
- Primary industry (SIC)
- 9999-Nonclassifiable Establishments
- Application ID
- 293096
- NOI processed
- Jun 28, 2005
- Last certified
- Feb 21, 2020
- Facility size
- 854
Retrieved from SMARTS Oct 20, 2026. Verify against SMARTS before relying on it.
Permit history
| Application | Type | Status | Processed | Terminated | Certified |
|---|---|---|---|---|---|
| 293096 | Industrial | Active | Jun 28, 2005 | — | Feb 21, 2020 |
Every storm water application SMARTS records for this WDID, newest first (1).
Receiving water
- Reported by the facility Evidence: facility-reported
- Little Wolf Creek
Evidence: unavailable Match status unavailable.
Impaired waters and TMDLs
Two kinds of information, kept apart: 2026 Integrated Report waterbodies near the reported location (geographic proximity only), and TMDL records that SMARTS lists for this facility. Neither establishes where the facility discharges; see Receiving water for the facility's own statement.
Nearby waterbodies Evidence: geographic proximity
Spatial proximity only; discharge pathway not established. Being near a waterbody does not mean the facility discharges to it.
Evidence: unavailable Unavailable.
SMARTS TMDL records Evidence: SMARTS-reported
Evidence: unavailable Unavailable.
Reported monitoring results Evidence: facility-reported
Numeric Action Level (NAL) screening is being independently validated and is not shown. Nothing on this page states whether a result exceeded a NAL.
3,013 distinct measurements across 19 parameters, most recent sample Feb 16, 2026.
By reporting year
| Reporting year (July–June) | Distinct results | Parameters | With several versions | First sample | Last sample |
|---|---|---|---|---|---|
| 2025 | 15 | 3 | 0 | Nov 05, 2025 | Feb 16, 2026 |
| 2024 | 18 | 3 | 0 | Nov 21, 2024 | Feb 04, 2025 |
| 2023 | 330 | 15 | 0 | Dec 19, 2023 | Feb 19, 2024 |
| 2022 | 390 | 15 | 0 | Nov 08, 2022 | Apr 07, 2023 |
| 2021 | 405 | 15 | 0 | Nov 09, 2021 | Apr 14, 2022 |
| 2020 | 266 | 15 | 0 | Dec 17, 2020 | Jan 28, 2021 |
| 2019 | 270 | 15 | 0 | Dec 02, 2019 | Apr 05, 2020 |
| 2018 | 376 | 15 | 0 | Nov 29, 2018 | Apr 02, 2019 |
| 2017 | 273 | 15 | 0 | Nov 16, 2017 | Mar 01, 2018 |
| 2016 | 350 | 13 | 0 | Nov 23, 2016 | Feb 16, 2017 |
| 2015 | 320 | 17 | 0 | Nov 24, 2015 | Apr 22, 2016 |
By parameter
| Parameter | Units | Measurements | Below detection | First sample | Last sample | Results |
|---|---|---|---|---|---|---|
| Total Suspended Solids (TSS) | mg/L | 220 | 51 | Nov 24, 2015 | Feb 16, 2026 | Results |
| pH | SU | 219 | 0 | Nov 24, 2015 | Feb 16, 2026 | Results |
| Oil and Grease | mg/L | 218 | 218 | Nov 24, 2015 | Feb 16, 2026 | Results |
| Aluminum, Total | mg/L | 209 | 31 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Arsenic, Total | mg/L | 209 | 32 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Cadmium, Total | mg/L | 209 | 133 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Copper, Total | mg/L | 209 | 41 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Hardness, Total (as CaCO3) | mg/L | 209 | 2 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Lead, Total | mg/L | 209 | 94 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Mercury, Total | ug/L | 209 | 192 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Zinc, Total | mg/L | 209 | 122 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Manganese, Total | mg/L | 200 | 99 | Nov 24, 2015 | Feb 19, 2024 | Results |
Show 7 more parameters
| Parameter | Units | Measurements | Below detection | First sample | Last sample | Results |
|---|---|---|---|---|---|---|
| Iron, Total | mg/L | 190 | 50 | Nov 24, 2015 | Feb 19, 2024 | Results |
| Iron, Total Recoverable | ug/L | 140 | 47 | Jan 08, 2018 | Feb 19, 2024 | Results |
| Manganese, Total Recoverable | mg/L | 133 | 64 | Jan 08, 2018 | Feb 19, 2024 | Results |
| Alkalinity, Carbonate (as CaCO3) | mg/L | 6 | 6 | Apr 22, 2016 | Apr 22, 2016 | Results |
| Alkalinity, Hydroxide (as CaCO3) | ug/L | 6 | 6 | Apr 22, 2016 | Apr 22, 2016 | Results |
| Alkalinity, Total (as CaCO3) | mg/L | 6 | 0 | Apr 22, 2016 | Apr 22, 2016 | Results |
| Alkalinity, Bicarbonate (as CaCO3) | mg/L | 3 | 0 | Apr 22, 2016 | Apr 22, 2016 | Results |
All results (3,013 distinct rows)
| Sample date | Parameter | Result | Units | Location type | Event | Method | Report | Versions |
|---|---|---|---|---|---|---|---|---|
| Dec 24, 2018 | Manganese, Total Recoverable | .027 | mg/L | Influent | Qualifying Storm Event | 1031852 | ||
| Dec 24, 2018 | Manganese, Total Recoverable | DNQ .0099 | mg/L | Influent | Qualifying Storm Event | 1031852 | ||
| Dec 24, 2018 | Manganese, Total Recoverable | .014 | mg/L | Internal | Qualifying Storm Event | 1031852 | ||
| Dec 24, 2018 | Manganese, Total Recoverable | DNQ .003 | mg/L | Effluent | Qualifying Storm Event | 1031852 | ||
| Dec 24, 2018 | Manganese, Total Recoverable | DNQ .0081 | mg/L | Effluent | Qualifying Storm Event | 1031852 | ||
| Dec 24, 2018 | Mercury, Total | ND | ug/L | Influent | Qualifying Storm Event | E245.2 | 1031852 | |
| Dec 24, 2018 | Mercury, Total | ND | ug/L | Influent | Qualifying Storm Event | E245.2 | 1031852 | |
| Dec 24, 2018 | Mercury, Total | ND | ug/L | Internal | Qualifying Storm Event | E245.2 | 1031852 | |
| Dec 24, 2018 | Mercury, Total | ND | ug/L | Effluent | Qualifying Storm Event | E245.2 | 1031852 | |
| Dec 24, 2018 | Mercury, Total | ND | ug/L | Effluent | Qualifying Storm Event | E245.2 | 1031852 | |
| Dec 24, 2018 | Oil and Grease | ND | mg/L | Influent | Qualifying Storm Event | E1664A | 1031852 | |
| Dec 24, 2018 | Oil and Grease | ND | mg/L | Influent | Qualifying Storm Event | E1664A | 1031852 | |
| Dec 24, 2018 | Oil and Grease | ND | mg/L | Internal | Qualifying Storm Event | E1664A | 1031852 | |
| Dec 24, 2018 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1031852 | |
| Dec 24, 2018 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1031852 | |
| Dec 24, 2018 | pH | 7.01 | SU | Influent | Qualifying Storm Event | pH_Field | 1031852 | |
| Dec 24, 2018 | pH | 7.01 | SU | Influent | Qualifying Storm Event | pH_Field | 1031852 | |
| Dec 24, 2018 | pH | 7.5 | SU | Internal | Qualifying Storm Event | pH_Field | 1031852 | |
| Dec 24, 2018 | pH | 7.51 | SU | Effluent | Qualifying Storm Event | pH_Field | 1031852 | |
| Dec 24, 2018 | pH | 6.75 | SU | Effluent | Qualifying Storm Event | pH_Field | 1031852 | |
| Dec 24, 2018 | Total Suspended Solids (TSS) | 8.6 | mg/L | Influent | Qualifying Storm Event | A2540D | 1031852 | |
| Dec 24, 2018 | Total Suspended Solids (TSS) | 3.3 | mg/L | Influent | Qualifying Storm Event | A2540D | 1031852 | |
| Dec 24, 2018 | Total Suspended Solids (TSS) | 11.8 | mg/L | Internal | Qualifying Storm Event | A2540D | 1031852 | |
| Dec 24, 2018 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1031852 | |
| Dec 24, 2018 | Total Suspended Solids (TSS) | 4.5 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1031852 | |
| Dec 24, 2018 | Zinc, Total | ND | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031852 | |
| Dec 24, 2018 | Zinc, Total | ND | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031852 | |
| Dec 24, 2018 | Zinc, Total | .059 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031852 | |
| Dec 24, 2018 | Zinc, Total | ND | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031852 | |
| Dec 24, 2018 | Zinc, Total | ND | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031852 | |
| Nov 29, 2018 | Aluminum, Total | .29 | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Aluminum, Total | .13 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Aluminum, Total | .12 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Aluminum, Total | DNQ .036 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Aluminum, Total | .16 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Aluminum, Total | .1 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | .0023 | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | .00063 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | .0072 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | DNQ .00042 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | .0022 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Arsenic, Total | .0064 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | ND | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | ND | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | .0011 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | ND | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | .00064 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Cadmium, Total | .001 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Copper, Total | .0015 | mg/L | Influent | Qualifying Storm Event | E200.8 | 1031862 | |
| Nov 29, 2018 | Copper, Total | DNQ .00069 | mg/L | Internal | Qualifying Storm Event | E200.8 | 1031862 |
Results are shown exactly as reported by the discharger. Identical rows repeated in the State's export are shown once. Where the export contains different versions of the same sample and parameter, each version is listed and flagged. Details.
Compliance and enforcement records Evidence: SMARTS record
These are records as the State Water Board publishes them in SMARTS, with the source's own types and statuses. They are not a compliance determination or rating. A record listed here is not proof of a violation beyond what the source states, and the absence of records does not establish compliance.
| Record type | Records | As published | Dates | Retrieved | List |
|---|---|---|---|---|---|
| Violations | 3 | 3 Violation · 0 Potential (preliminary) · 0 Dismissed | Mar 30, 2006 – Oct 14, 2010 | Oct 21, 2026 | All violations |
| Enforcement actions | 3 | 3 issued · 0 draft · 0 withdrawn, rescinded or superseded | Mar 30, 2007 – Oct 14, 2010 | Oct 21, 2026 | All actions |
| Inspections | 2 | inspections, not findings | Nov 04, 2009 – Nov 15, 2017 | Oct 21, 2026 | All inspections |
| Annual reports | 11 | certified reports (contents not shown) | 2015 – 2025 | Oct 21, 2026 | All reports |
| Water-quality-based corrective action reports | 0 | reports, by parameter | — | Oct 21, 2026 |
Each record type is counted by its own SMARTS identifier. A violation and the enforcement action that cites it are two records in two lists; they are never added together.
Chronological record history (19 records, newest first)
| Date | Record | ID | Type or purpose | Status as published | Detail |
|---|---|---|---|---|---|
| Jul 01, 2026 | Annual reports | 1335328 | Annual report 2025 | — | |
| Jun 26, 2025 | Annual reports | 1294140 | Annual report 2024 | — | |
| Jul 12, 2024 | Annual reports | 1243223 | Annual report 2023 | — | |
| Jul 14, 2023 | Annual reports | 1189225 | Annual report 2022 | — | |
| Jul 07, 2022 | Annual reports | 1112596 | Annual report 2021 | — | |
| Jun 14, 2021 | Annual reports | 1068603 | Annual report 2020 | — | |
| Jun 22, 2020 | Annual reports | 985856 | Annual report 2019 | — | |
| May 29, 2019 | Annual reports | 953408 | Annual report 2018 | — | |
| May 29, 2018 | Annual reports | 938824 | Annual report 2017 | — | |
| Nov 15, 2017 | Inspections | 2035659 | B Type compliance | — | No Further Action |
| Aug 02, 2017 | Annual reports | 878056 | Annual report 2016 | — | |
| Jul 06, 2016 | Annual reports | 846520 | Annual report 2015 | — | |
| Oct 14, 2010 | Enforcement actions | 403186 | SEL (Staff Enforcement Letter) | Historical | |
| Oct 14, 2010 | Violations | 842924 | Deficient BMP Implementation | Violation | Report |
| Nov 04, 2009 | Inspections | 2001154 | B Type compliance | — | No Further Action |
| May 01, 2008 | Enforcement actions | 347503 | SEL (Staff Enforcement Letter) | Active | |
| Jul 01, 2007 | Violations | 765686 | Deficient BMP Implementation | Violation | Storm Water Discharge |
| Mar 30, 2007 | Enforcement actions | 325280 | NOV (Notice of Violation) | Active | |
| Mar 30, 2006 | Violations | 496700 | Deficient Report | Violation | Report |
Sources and provenance
| Information | Source | Retrieved or published |
|---|---|---|
| Permit, location, receiving-water text | SMARTS Industrial Application Specific Data | Oct 20, 2026 |
| Permit history | SMARTS Storm Water Applications | Oct 20, 2026 |
| Monitoring results | SMARTS Industrial Parameter Data | Oct 20, 2026 |
How to read the evidence labels
- Evidence: SMARTS record Evidence: facility-reported Information as published in SMARTS or reported by the discharger.
- Evidence: identification corroborated The reported receiving-water name identifies one official waterbody and the facility's location is consistent with it. It does not establish a discharge pathway.
- Evidence: candidate, awaiting review Evidence: not confirmed The reported name could match one or more official waterbodies, but no identification has been confirmed; nothing is assigned without review.
- Evidence: spatial Evidence: geographic proximity Derived from the reported location only.
- Evidence: SMARTS-reported Source records whose links to official references are not yet reviewed.
- Evidence: unavailable The information could not be loaded or is not in the sources.
Records are shown as published and are not compliance determinations. How geographic context is derived.