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Industrial stormwater facility

Georgia Pacific Gypsum LLC

5S07I020674 · Notice of Intent · Antioch, Contra Costa

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

Official

Facility record

Facility name
Georgia Pacific Gypsum LLC
WDID
5S07I020674
Application type
Notice of Intent
City
Antioch
County
Contra Costa
ZIP
94509
Primary SIC code
3275
SIC description
Gypsum Products
Date active
2007-02-13
Regional Water Board
Regional Board 5 - Central Valley Region

Hydrologic

Geographic context

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

Official facility point
38.01323, -121.79163
HUC12 subwatershed
Markley Canyon-San Joaquin River
HUC12 code
180400030907
Impaired-water associations (derived)
3
Loading map…

303(d) context

Associated impaired waters

Grouped by derived geographic association class.

Derived

Same impaired-water subwatershed

3 waterbodies
Contra Costa Canal (in Delta Waterways, western portion)

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (1) pH

Distance

Confidence low

Fact sheet

Sacramento San Joaquin Delta

Estuary · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (10) Chlordane, DDT (Dichlorodiphenyltrichloroethane), Dieldrin, Dioxin compounds (including 2,3,7,8-TCDD), Furan Compounds, Invasive Species +4 more

Distance

Confidence low

Fact sheet

San Joaquin River (in Delta Waterways, western and central portions to Stockton Ship Channel)

River & Stream · Integrated Report category 5 · TMDL required

Listed pollutants / stressors (7) Arsenic, Chlordane, DDT (Dichlorodiphenyltrichloroethane), Dieldrin, PAHs (Polycyclic Aromatic Hydrocarbons), PCBs (Polychlorinated biphenyls) +1 more

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

Water Board-stated TMDL waste load allocations applied to this industrial permit in SMARTS.

Official record — SMARTS TMDL dataset, State Water Board

No SMARTS TMDL requirement is recorded for this WDID. In the statewide TMDL export only permits in Regions 4, 8 and 9 currently carry industrial TMDL requirements, so an absence here is not a statement that the facility discharges to an unimpaired water.

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
34
Sample events
5
Distinct parameters
12
Reporting years
2015 – 2024
First sample
2016-01-19
Latest sample
2025-02-13
Source regional dataset
Region 5S - Sacramento
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 34
Sample dateLocationParameterResultUnitsEvent
2025-02-13Outfall 001Iron.035mg/LQualifying Storm Event
2025-02-13Outfall 001LeadND (non-detect / est.)mg/LQualifying Storm Event
2025-02-13Outfall 001MercuryND (non-detect / est.)ug/LQualifying Storm Event
2025-02-13Outfall 001Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2025-02-13Outfall 001pH7.65SUQualifying Storm Event
2025-02-13Outfall 001Total Suspended Solids (TSS)1.4mg/LQualifying Storm Event
2023-01-14Outfall 001Iron.059mg/LQualifying Storm Event
2023-01-14Outfall 001LeadND (non-detect / est.)mg/LQualifying Storm Event
2023-01-14Outfall 001MercuryND (non-detect / est.)ug/LQualifying Storm Event
2023-01-14Outfall 001Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2023-01-14Outfall 001pH6.04SUQualifying Storm Event
2023-01-14Outfall 001Total Suspended Solids (TSS)ND (non-detect / est.)mg/LQualifying Storm Event
2023-01-09Outfall 001Iron.14mg/LQualifying Storm Event
2023-01-09Outfall 001LeadND (non-detect / est.)mg/LQualifying Storm Event
2023-01-09Outfall 001MercuryND (non-detect / est.)ug/LQualifying Storm Event
2023-01-09Outfall 001Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2023-01-09Outfall 001pH6.05SUQualifying Storm Event
2023-01-09Outfall 001Total Suspended Solids (TSS)ND (non-detect / est.)mg/LQualifying Storm Event
2022-12-31Outfall 001Iron.73mg/LQualifying Storm Event
2022-12-31Outfall 001Lead.0021mg/LQualifying Storm Event
2022-12-31Outfall 001MercuryND (non-detect / est.)ug/LQualifying Storm Event
2022-12-31Outfall 001Oil and GreaseND (non-detect / est.)mg/LQualifying Storm Event
2022-12-31Outfall 001pH6.15SUQualifying Storm Event
2022-12-31Outfall 001Total Suspended Solids (TSS)5.33mg/LQualifying Storm Event
2016-01-19Outfall 001AluminumND (non-detect / est.)mg/LQualifying 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
3
Years with an NAL exceedance
0
Most recent evaluated year
RY 2024
Ruleset
igp_nal_ruleset_v1 / igp_nal_v1
ParameterNAL typeCalculated valueNALResultSamples usedMethod

Iron, Total

iron_total

Annual0.035 mg/L1 mg/LAt or below NALAnnual average of 1 eligible result(s) compared with the annual NAL.0.04× threshold1 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)

Lead, Total

lead_total

Annual0 mg/L0.262 mg/LAt or below NALAnnual average of 1 eligible result(s) compared with the annual NAL.0× threshold1 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)

Mercury, Total

mercury_total

Annual0 mg/L0.001 mg/LAt or below NALAnnual average of 1 eligible result(s) compared with the annual NAL.0× threshold1 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.1 eligible1 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.1 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.1 eligiblecount of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year

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
5S07I020674
Source feature ID
14253
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