Industrial stormwater facility
2 41I016184 · Notice of Intent · South San Francisco, San Mateo
Official
Hydrologic
Official facility coordinate plotted against the official 2026 impaired-water geometry.
303(d) context
Grouped by derived geographic association class.
Bay & Harbor · 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
Coastal & Bay Shoreline · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (1) Indicator Bacteria
Bay & Harbor · Integrated Report category 5 · TMDL required
Listed pollutants / stressors (11) Chlordane, DDT (Dichlorodiphenyltrichloroethane), Dieldrin, Dioxin compounds (including 2,3,7,8-TCDD), Furan Compounds, Invasive Species +5 more
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.
Water Board-stated TMDL waste load allocations applied to this industrial permit in SMARTS.
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.
YDOS-derived
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).
| Parameter | NAL type | Calculated value | NAL | Result | Samples used | Method |
|---|---|---|---|---|---|---|
Aluminum, Total aluminum_total | Annual | 0.734 mg/L | 0.75 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.98× threshold | 13 eligible | arithmetic 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) |
Ammonia, Total (as N) ammonia_n | Annual | 1.025 mg/L | 2.14 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.48× threshold | 13 eligible4 non-detect as zero | arithmetic 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) |
Arsenic, Total arsenic_total | Annual | 0.009 mg/L | 0.15 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.06× threshold | 13 eligible6 non-detect as zero | arithmetic 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) |
Cadmium, Total cadmium_total | Annual | 0 mg/L | 0.005 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0× threshold | 13 eligible13 non-detect as zero | arithmetic 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) |
Chemical Oxygen Demand (COD) cod | Annual | 395.25 mg/L | 120 mg/L | Above NALAnnual average of 12 eligible result(s) compared with the annual NAL.3.29× threshold | 12 eligible | arithmetic 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 | Annual | 0.012 mg/L | 0.033 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.38× threshold | 13 eligible4 non-detect as zero | arithmetic 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 | Annual | 1.595 mg/L | 1 mg/L | Above NALAnnual average of 13 eligible result(s) compared with the annual NAL.1.6× threshold | 13 eligible1 non-detect as zero | arithmetic 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 | Annual | 1.46e-4 mg/L | 0.262 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.5.58e-4× threshold | 13 eligible12 non-detect as zero | arithmetic 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 | Annual | 0 mg/L | 0.001 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0× threshold | 13 eligible13 non-detect as zero | arithmetic 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 | Annual | 0.015 mg/l | 1.02 mg/l | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.02× threshold | 13 eligible3 non-detect as zero | arithmetic 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) |
Nitrite Plus Nitrate (as N) nitrate_nitrite_n | Annual | 2.13 mg/L as N | 0.68 mg/L as N | Above NALAnnual average of 13 eligible result(s) compared with the annual NAL.3.13× threshold | 13 eligible | arithmetic 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 maximum | —1 sample above | 25 mg/L | At or below NALOne eligible result in this reporting year was outside the instantaneous maximum NAL. The Order states the condition as two or more results in one reporting year. | 12 eligible8 non-detect as zero | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
pH ph | Instantaneous maximum | —6 samples above | 6 – 9 pH units | Outside NAL range6 eligible results in this reporting year were outside the instantaneous maximum NAL. Two or more such results in one reporting year is the condition stated in the Order. | 13 eligible | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
Selenium, Total selenium_total | Annual | 0.009 mg/L | 0.005 mg/L | Above NALAnnual average of 13 eligible result(s) compared with the annual NAL.1.89× threshold | 13 eligible9 non-detect as zero | arithmetic 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) |
Silver, Total silver_total | Annual | 0 mg/L | 0.018 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0× threshold | 13 eligible13 non-detect as zero | arithmetic 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) |
Total Suspended Solids (TSS) tss | Instantaneous maximum | —2 samples above | 400 mg/L | Above NAL2 eligible results in this reporting year were outside the instantaneous maximum NAL. Two or more such results in one reporting year is the condition stated in the Order. | 13 eligible | count of eligible effluent results outside the instantaneous maximum NAL within the July 1 - June 30 reporting year |
Zinc, Total zinc_total | Annual | 0.002 mg/L | 0.26 mg/L | At or below NALAnnual average of 13 eligible result(s) compared with the annual NAL.0.01× threshold | 13 eligible12 non-detect as zero | arithmetic 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) |
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