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Industrial stormwater facility

Miller Castings Inc

4 19I022672 · Notice of Intent · Whittier, Los Angeles

Official record — State Water Resources Control Board, Industrial General Permit

Official

Facility record

Facility name
Miller Castings Inc
WDID
4 19I022672
Application type
Notice of Intent
City
Whittier
County
Los Angeles
ZIP
90601
Primary SIC code
3324
SIC description
Steel Investment Foundries
Date active
2010-06-15
Regional Water Board
Regional Board 4 - Los Angeles Region

Hydrologic

Geographic context

Official facility coordinate plotted against the official 2026 impaired-water geometry.

Official facility point
34.03017, -118.03936
HUC12 subwatershed
Coyote Creek-San Gabriel River
HUC12 code
180701060606
Impaired-water associations (derived)
6
Loading map…

303(d) context

Associated impaired waters

Grouped by derived geographic association class.

Derived

Subwatershed + nearby

1 waterbodies
San Gabriel River Reach 3 (Whittier Narrows to Ramona)

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (2) Chlorine, Indicator Bacteria

Distance 0.29 km

Confidence high

Fact sheet

Same impaired-water subwatershed

5 waterbodies
Alamitos Bay

Bay & Harbor · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (6) Copper, DDD (Dichlorodiphenyldichloroethane), DDT (Dichlorodiphenyltrichloroethane), Indicator Bacteria, Oxygen, Dissolved, PCBs (Polychlorinated biphenyls)

Distance

Confidence low

Fact sheet

Coyote Creek

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (8) Aluminum, Chlorine, Copper, Dissolved, Indicator Bacteria, Iron, Malathion +2 more

Distance

Confidence low

Fact sheet

El Dorado Lakes

Lake & Reservoir · Integrated Report category 4a · TMDL approved by USEPA

Listed pollutants / stressors (7) Algae, Ammonia, Copper, Eutrophic, Lead, Mercury +1 more

Distance

Confidence low

Fact sheet

San Gabriel River Estuary

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (7) Chlordane, Chlorine, Copper, Dioxin, Indicator Bacteria, Nickel +1 more

Distance

Confidence low

Fact sheet

San Gabriel River Reach 1 (Estuary to Firestone)

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (3) Indicator Bacteria, Oil and Grease, pH

Distance

Confidence low

Fact sheet

Associations are calculated from official facility coordinates, USGS HUC12 boundaries, and official 2026 impaired-water geometry. They do not establish a discharge connection or causation.

TMDL requirements (1)

Numeric effluent limits and action levels stated by the Water Board for this permit, with the receiving water named in the TMDL.

Official record — SMARTS TMDL dataset, State Water Board
Stated requirements
1
TMDLs
1
Regulated parameters
1
Limit due dates
2020-07-01 – 2020-07-01
Includes interim limits
No
Source regional dataset
Region 4 - Los Angeles
Source retrieved
Aug 21, 2026

Official SMARTS public reports

R4 - San Gabriel River Metals and Selenium TMDL

Receiving water named in TMDL San Gabriel River Reach 2 and its tributary/ies

1 limits
ParameterLimit typePeriodBasisLimitDue dateReported results for parameter
Lead, TotalVocabulary match: Lead (narrower)NELFINALINSTANTANEOUS.166 mg/L2020-07-0173 results · latest 2026-02-16
Derivedapplies only to the 303(d) waterbody link and the parameter vocabulary match.

Limit values, limit periods, parameters, TMDL names and receiving-water names are reproduced exactly as stated by the Water Board in SMARTS. California Stormwater Intelligence does not compare reported monitoring results to these limits and makes no exceedance, violation or compliance determination. Where a stated receiving-water name is linked to a 2026 303(d) waterbody, that link is a derived exact-name match, not a Water Board determination.

Official monitoring

SMARTS monitoring

Self-reported industrial stormwater sampling results as submitted by the discharger to SMARTS.

Official record — SMARTS parameter data, State Water Board
Reported results
774
Sample events
88
Distinct parameters
10
Reporting years
2015 – 2025
First sample
2015-09-15
Latest sample
2026-02-16
Source regional dataset
Region 4 - Los Angeles
Source retrieved
Aug 21, 2026

Official SMARTS public reports

Parameters reported

Reported results over time

Loading reported results…

Most recent reported results

Latest 25 of 774
Sample dateLocationParameterResultUnitsEvent
2026-02-16S-1Aluminum.77mg/LQualifying Storm Event
2026-02-16S-1Copper.018mg/LQualifying Storm Event
2026-02-16S-1Iron1.05mg/LQualifying Storm Event
2026-02-16S-1LeadDNQ .0036(non-detect / est.)mg/LQualifying Storm Event
2026-02-16S-1Nickel.031mg/LQualifying Storm Event
2026-02-16S-1Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-02-16S-1pH8.88SUQualifying Storm Event
2026-02-16S-1Total Suspended Solids (TSS)36mg/LQualifying Storm Event
2026-02-16S-1Zinc.176mg/LQualifying Storm Event
2026-02-16S-4Aluminum.38mg/LQualifying Storm Event
2026-02-16S-4Copper.0061mg/LQualifying Storm Event
2026-02-16S-4Iron.514mg/LQualifying Storm Event
2026-02-16S-4LeadDNQ .0014(non-detect / est.)mg/LQualifying Storm Event
2026-02-16S-4Nickel.017mg/LQualifying Storm Event
2026-02-16S-4Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2026-02-16S-4pH8.99SUQualifying Storm Event
2026-02-16S-4Total Suspended Solids (TSS)12mg/LQualifying Storm Event
2026-02-16S-4Zinc.0779mg/LQualifying Storm Event
2025-11-20S-1Aluminum.12mg/LQualifying Storm Event
2025-11-20S-1Copper.088mg/LQualifying Storm Event
2025-11-20S-1Iron.186mg/LQualifying Storm Event
2025-11-20S-1Lead.00061mg/LQualifying Storm Event
2025-11-20S-1Nickel.0024mg/LQualifying Storm Event
2025-11-20S-1Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-11-20S-1pH7SUQualifying Storm Event

Monitoring rows are official self-reported SMARTS submissions, joined to this facility by WDID. California Stormwater Intelligence does not restate, correct, average or evaluate reported values, and no benchmark comparison or violation determination is made.

YDOS-derived

Numeric Action Level comparison

Reported SMARTS analytical results compared against the Numeric Action Levels of the Industrial General Permit version in effect for each reporting year (July 1 – June 30).

Derived
Reporting years evaluated
11
Years with an NAL exceedance
7
Most recent evaluated year
RY 2025
Ruleset
igp_nal_ruleset_v1 / igp_nal_v1
ParameterNAL typeCalculated valueNALResultSamples usedMethod

Aluminum, Total

aluminum_total

Annual0.269 mg/L0.75 mg/LAt or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.36× threshold8 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Copper, Total

copper_total

Annual0.049 mg/L0.033 mg/LAbove NALAnnual average of 8 eligible result(s) compared with the annual NAL.1.47× threshold8 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Iron, Total

iron_total

Annual0.317 mg/L1 mg/LAt or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.32× threshold8 eligible1 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Lead, Total

lead_total

Annual3.73e-4 mg/L0.262 mg/LAt or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0× threshold8 eligible5 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Nickel, Total

nickel_total

Annual0.009 mg/l1.02 mg/lAt or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.01× threshold8 eligible1 non-detect as zeroarithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

Oil and Grease

oil_grease

Instantaneous maximum0 samples above25 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.8 eligible8 non-detect as zerocount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

pH

ph

Instantaneous maximum0 samples above6 – 9 pH unitsWithin NAL rangeNo eligible result in this reporting year was outside the instantaneous maximum NAL.8 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

Total Suspended Solids (TSS)

tss

Instantaneous maximum0 samples above400 mg/LAt or below NALNo eligible result in this reporting year was outside the instantaneous maximum NAL.8 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

Zinc, Total

zinc_total

Annual0.135 mg/L0.26 mg/LAt or below NALAnnual average of 8 eligible result(s) compared with the annual NAL.0.52× threshold8 eligiblearithmetic mean of all eligible effluent results in the July 1 - June 30 reporting year (censored results assigned zero only where MDL and ML were both reported)

YDOS-derived overlap

Pollutant overlap with impaired receiving waters

Parameters where this facility has an NAL exceedance in at least one reporting year and the geographically associated waterbody carries a 303(d) listing for the same pollutant.

Derived

AluminumMonitoringAbove NAL303(d) impairmentCoyote Creek

5 reporting years above the annual NAL, most recently RY 2022 · 1 303(d) listing · association: derived watershed association (low confidence)

CopperMonitoringAbove NAL303(d) impairmentAlamitos Bay

3 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · association: derived watershed association (low confidence)

CopperMonitoringAbove NAL303(d) impairmentEl Dorado Lakes

3 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · association: derived watershed association (low confidence)

CopperMonitoringAbove NAL303(d) impairmentSan Gabriel River Estuary

3 reporting years above the annual NAL, most recently RY 2025 · 1 303(d) listing · association: derived watershed association (low confidence)

IronMonitoringAbove NAL303(d) impairmentCoyote Creek

1 reporting year above the annual NAL, most recently RY 2019 · 1 303(d) listing · association: derived watershed association (low confidence)

Overlap is informational co-occurrence between a derived NAL comparison and an official 303(d) listing. It is not evidence that this facility caused or contributed to the impairment.

An NAL exceedance is a permit-defined condition that triggers Exceedance Response Actions under the Industrial General Permit. It is not a violation, an enforcement action, or a Water Board compliance determination. Annual values use the arithmetic average of eligible results with non-detects treated as zero; instantaneous maximum NALs (total suspended solids, oil and grease, pH) are exceeded when two or more eligible results in a reporting year fall outside the level. Rules transcribed from 2014-0057-DWQ as amended by 2015-0122-DWQ (effective 2015-07-01, superseded 2020-06-30); 2014-0057-DWQ as amended by 2018-0028-DWQ (effective 2020-07-01).

Provenance

Source & provenance

Source agency
California State Water Resources Control Board
Source dataset
Industrial General Permit — permitted facilities (statewide GIS layer)
WDID
4 19I022672
Source feature ID
12243
Application type
Notice of Intent
Regional board derivation
WDID region prefix
Geometry status
valid
Last successful facility import
Aug 21, 2026, 1:57 AM UTC

Official IGP permitted facilities feature layer