Semco Ent Inc
Active WDID 4 19I001679 City Of Industry, Los Angeles County Region 4 · Los Angeles
At a glance
- Permit Evidence: SMARTS record
- Active Industrial
- Notice of Intent (WDID code I) · Permits and applications
- Location Evidence: facility-reported
- City Of Industry, Los Angeles County
- Region 4 · Los Angeles · Location · Statewide map
- Receiving water
- San Gabriel River (as reported by the facility)
- Evidence: candidate, awaiting review 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
- 1 waterbody; 1 on the 2026 303(d) list
- Proximity only; not a discharge pathway · Nearby waterbodies
- Monitoring results Evidence: facility-reported
- 227 distinct results, 10 reporting years (2015 to 2024)
- Most recent sample Mar 13, 2025 · Monitoring
- Compliance and enforcement records Evidence: SMARTS record
- 3 inspections · 3 violation records · 2 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
- Coordinates
- 34.01636, -117.95664
- Precision
- 5 decimal places
- Shared point
- No
- Matches application record
- same
Facility location as reported by the discharger in SMARTS; not a discharge point or outfall.
- Facility address
- 475 Wilson Way, City Of Industry 91744
- Regional Water Board
- 4 — Los Angeles
HUC12 watershed Evidence: spatial
- Lower San Jose Creek HUC12 180701060502
The facility's reported location lies within this HUC12 watershed (spatial derivation); it is not a discharge location.
Permits and applications Evidence: SMARTS record
Current permit record
- Permit type
- Industrial
- Application type
- Notice of Intent (WDID code I)
- Status
- Active
- Operator
- Semco Ent Inc
- Primary industry (SIC)
- 3341-Secondary Smelting and Refining of Nonferrous Metals
- Application ID
- 188835
- NOI processed
- Mar 27, 1992
- Last certified
- Apr 08, 2015
- Facility size
- 2 Acres
Retrieved from SMARTS Oct 20, 2026. Verify against SMARTS before relying on it.
Permit history
| Application | Type | Status | Processed | Terminated | Certified |
|---|---|---|---|---|---|
| 188835 | Industrial | Active | Mar 27, 1992 | — | Apr 08, 2015 |
Every storm water application SMARTS records for this WDID, newest first (1).
Receiving water
- Reported by the facility Evidence: facility-reported
- San Gabriel River
- Discharges directly / indirectly
- N / Y (as answered in the permit application)
Evidence: not confirmed Evidence: candidate, awaiting review Awaiting review
Receiving-water text as reported by the discharger in SMARTS; no waterbody identification has been confirmed.
Why it is not confirmed (1)
- C1 name is only a prefix of official names
10 official waterbodies share this name; none is assigned without review.
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.
| Waterbody (2026 Integrated Report) | Distance | 2026 303(d) list | Appendix A decisions |
|---|---|---|---|
| San Jose Creek Reach 1 (SG Confluence to Temple St.) CAR4053100019980918090950 | 297 m | listed | 5 |
Waterbodies within 1.0 km of the reported facility location. Method proximity/1.
SMARTS TMDL records Evidence: SMARTS-reported
No TMDL records for this facility in the SMARTS TMDL export.
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.
227 distinct measurements across 7 parameters, most recent sample Mar 13, 2025.
By reporting year
| Reporting year (July–June) | Distinct results | Parameters | With several versions | First sample | Last sample |
|---|---|---|---|---|---|
| 2024 | 10 | 5 | 0 | Mar 13, 2025 | Mar 13, 2025 |
| 2023 | 10 | 5 | 0 | Feb 01, 2024 | Feb 01, 2024 |
| 2022 | 20 | 5 | 0 | Mar 15, 2023 | Mar 29, 2023 |
| 2021 | 10 | 5 | 0 | Dec 14, 2021 | Dec 14, 2021 |
| 2020 | 10 | 5 | 0 | Jan 29, 2021 | Jan 29, 2021 |
| 2019 | 35 | 6 | 0 | Nov 20, 2019 | Mar 10, 2020 |
| 2018 | 34 | 6 | 0 | Nov 29, 2018 | Feb 14, 2019 |
| 2017 | 24 | 6 | 0 | Jan 08, 2018 | Mar 22, 2018 |
| 2016 | 60 | 6 | 0 | Dec 22, 2016 | Mar 22, 2017 |
| 2015 | 14 | 7 | 0 | Sep 15, 2015 | Sep 15, 2015 |
By parameter
| Parameter | Units | Measurements | Below detection | First sample | Last sample | Results |
|---|---|---|---|---|---|---|
| Copper, Total | mg/L | 40 | 7 | Sep 15, 2015 | Mar 13, 2025 | Results |
| Total Suspended Solids (TSS) | mg/L | 40 | 15 | Sep 15, 2015 | Mar 13, 2025 | Results |
| Zinc, Total | mg/L | 40 | 0 | Sep 15, 2015 | Mar 13, 2025 | Results |
| Oil and Grease | mg/L | 39 | 12 | Sep 15, 2015 | Mar 13, 2025 | Results |
| pH | SU | 38 | 0 | Sep 15, 2015 | Mar 13, 2025 | Results |
| Total Organic Carbon (TOC) | mg/L | 28 | 0 | Sep 15, 2015 | Mar 10, 2020 | Results |
| Electrical Conductivity @ 25 Deg. C | umhos/cm | 2 | 0 | Sep 15, 2015 | Sep 15, 2015 | Results |
All results (227 distinct rows)
| Sample date | Parameter | Result | Units | Location type | Event | Method | Report | Versions |
|---|---|---|---|---|---|---|---|---|
| Mar 13, 2025 | Copper, Total | .00265 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1327961 | |
| Mar 13, 2025 | Copper, Total | .00324 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1327961 | |
| Mar 13, 2025 | Oil and Grease | 3.39 | mg/L | Effluent | Qualifying Storm Event | E1664B | 1327961 | |
| Mar 13, 2025 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664B | 1327961 | |
| Mar 13, 2025 | pH | 6.7 | SU | Effluent | Qualifying Storm Event | pH_Field | 1327961 | |
| Mar 13, 2025 | pH | 6.7 | SU | Effluent | Qualifying Storm Event | pH_Field | 1327961 | |
| Mar 13, 2025 | Total Suspended Solids (TSS) | .7 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1327961 | |
| Mar 13, 2025 | Total Suspended Solids (TSS) | .8 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1327961 | |
| Mar 13, 2025 | Zinc, Total | .274 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1327961 | |
| Mar 13, 2025 | Zinc, Total | .443 | mg/L | Effluent | Qualifying Storm Event | E200.8 | 1327961 | |
| Feb 01, 2024 | Copper, Total | .0015 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1279944 | |
| Feb 01, 2024 | Copper, Total | .004 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1279944 | |
| Feb 01, 2024 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1279944 | |
| Feb 01, 2024 | Oil and Grease | .9 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1279944 | |
| Feb 01, 2024 | pH | 6.8 | SU | Effluent | Qualifying Storm Event | pH_Field | 1279944 | |
| Feb 01, 2024 | pH | 6.4 | SU | Effluent | Qualifying Storm Event | pH_Field | 1279944 | |
| Feb 01, 2024 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1279944 | |
| Feb 01, 2024 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1279944 | |
| Feb 01, 2024 | Zinc, Total | .15 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1279944 | |
| Feb 01, 2024 | Zinc, Total | .2 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1279944 | |
| Mar 29, 2023 | Copper, Total | DNQ .004 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235508 | |
| Mar 29, 2023 | Copper, Total | DNQ .0031 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235508 | |
| Mar 29, 2023 | Oil and Grease | DNQ 1.8 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1235508 | |
| Mar 29, 2023 | Oil and Grease | DNQ 1.8 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1235508 | |
| Mar 29, 2023 | pH | 7.89 | SU | Effluent | Qualifying Storm Event | pH_Field | 1235508 | |
| Mar 29, 2023 | pH | 7.73 | SU | Effluent | Qualifying Storm Event | pH_Field | 1235508 | |
| Mar 29, 2023 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1235508 | |
| Mar 29, 2023 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1235508 | |
| Mar 29, 2023 | Zinc, Total | .42 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235508 | |
| Mar 29, 2023 | Zinc, Total | .34 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235508 | |
| Mar 15, 2023 | Copper, Total | ND | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235482 | |
| Mar 15, 2023 | Copper, Total | ND | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235482 | |
| Mar 15, 2023 | Oil and Grease | DNQ 1.1 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1235482 | |
| Mar 15, 2023 | Oil and Grease | ND | mg/L | Effluent | Qualifying Storm Event | E1664A | 1235482 | |
| Mar 15, 2023 | pH | 7.61 | SU | Effluent | Qualifying Storm Event | pH_Field | 1235482 | |
| Mar 15, 2023 | pH | 7.52 | SU | Effluent | Qualifying Storm Event | pH_Field | 1235482 | |
| Mar 15, 2023 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1235482 | |
| Mar 15, 2023 | Total Suspended Solids (TSS) | .3 | mg/L | Effluent | Qualifying Storm Event | A2540D | 1235482 | |
| Mar 15, 2023 | Zinc, Total | .16 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235482 | |
| Mar 15, 2023 | Zinc, Total | .19 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1235482 | |
| Dec 14, 2021 | Copper, Total | .0014 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1185976 | |
| Dec 14, 2021 | Copper, Total | .0029 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1185976 | |
| Dec 14, 2021 | Oil and Grease | DNQ 4 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1185976 | |
| Dec 14, 2021 | Oil and Grease | 4.2 | mg/L | Effluent | Qualifying Storm Event | E1664A | 1185976 | |
| Dec 14, 2021 | pH | 7.7 | SU | Effluent | Qualifying Storm Event | pH_Field | 1185976 | |
| Dec 14, 2021 | pH | 7.7 | SU | Effluent | Qualifying Storm Event | pH_Field | 1185976 | |
| Dec 14, 2021 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1185976 | |
| Dec 14, 2021 | Total Suspended Solids (TSS) | ND | mg/L | Effluent | Qualifying Storm Event | A2540D | 1185976 | |
| Dec 14, 2021 | Zinc, Total | .081 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1185976 | |
| Dec 14, 2021 | Zinc, Total | .11 | mg/L | Effluent | Qualifying Storm Event | E200.7 | 1185976 |
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 | Oct 20, 2004 – Nov 25, 2008 | Oct 21, 2026 | All violations |
| Enforcement actions | 2 | 2 issued · 0 draft · 0 withdrawn, rescinded or superseded | Oct 20, 2004 – Jun 21, 2010 | Oct 21, 2026 | All actions |
| Inspections | 3 | inspections, not findings | Feb 08, 2002 – Oct 20, 2004 | 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 14, 2026 | Annual reports | 1334386 | Annual report 2025 | — | |
| Jul 03, 2025 | Annual reports | 1293167 | Annual report 2024 | — | |
| Jul 03, 2024 | Annual reports | 1242185 | Annual report 2023 | — | |
| Jul 06, 2023 | Annual reports | 1188135 | Annual report 2022 | — | |
| Jun 20, 2022 | Annual reports | 1111418 | Annual report 2021 | — | |
| Jul 02, 2021 | Annual reports | 1067368 | Annual report 2020 | — | |
| Jul 06, 2020 | Annual reports | 984544 | Annual report 2019 | — | |
| Jul 03, 2019 | Annual reports | 952054 | Annual report 2018 | — | |
| Jun 29, 2018 | Annual reports | 937466 | Annual report 2017 | — | |
| Jun 26, 2017 | Annual reports | 876630 | Annual report 2016 | — | |
| Jun 22, 2016 | Annual reports | 841279 | Annual report 2015 | — | |
| Jun 21, 2010 | Enforcement actions | 404269 | SEL (Staff Enforcement Letter) | Historical | |
| Nov 25, 2008 | Violations | 843586 | Deficient BMP Implementation | Violation | Report |
| Oct 20, 2004 | Enforcement actions | 253722 | NTC (Notice to Comply) | Historical | UNKNOWN |
| Oct 20, 2004 | Inspections | 1734635 | B Type compliance | — | Additional Info Required |
| Oct 20, 2004 | Violations | 259877 | Deficient BMP Implementation | Violation | Inspection |
| Oct 20, 2004 | Violations | 259878 | Deficient BMP Implementation | Violation | Inspection |
| Feb 21, 2002 | Inspections | 1734634 | Enforcement Follow-up | — | Additional Info Required |
| Feb 08, 2002 | Inspections | 1734633 | B Type compliance | — | Additional Info Required |
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 |
| Watershed Boundary Dataset HU2 GeoPackages 15, 16, 18 (WBDHU12) | USGS | 2026-10-22 |
| 2026 California Integrated Report, Appendix A: 2026 303(d) List (final) | SWRCB | 2026-10-22 |
| Final_2026_Rivers_and_Streams + Final_2026_Lakes_and_Reservoirs (FeatureServer 0) | SWRCB GIS | 2026-10-22 |
| SMARTS TMDL requirements | SMARTS | 2026-10-21 |
Relationships computed 2026-10-22 with methods facility_huc12/1, proximity/1, receiving_water/2, tmdl_reference/1, waterbody_huc12_ovl/1, waterbody_huc12_pub/1; proximity threshold 1.0 km.
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.