Leadville Sanitation District — NPDES permit CO0021164: limits, due date and EPA's record

Sewage treatment plant, major discharger, Leadville, Colorado. NPDES permit CO0021164 expired Dec 31, 2025; its limits still apply. Last 12 months: over a limit 5 times (last June 2026), 2 of 30 reports late. Source: EPA ECHO, Oct 22, 2026.

Last 12 months (Oct 1, 2025 – Sep 30, 2026)

Period ending	Parameter	Reported	Limit	Over by
October 2025	pH, minimum	5.7 SU	≥ 6.5 SU	—
December 2025	LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia, minimum value	41.8 %	≥ 100 %	58%
April 2026	Chlorine, total residual, instantaneous maximum	.61 mg/L	≤ .48 mg/L	27%
June 2026	E. coli, 30-day geometric mean	1413.6 #/100mL	≤ 630 #/100mL	124%
June 2026	E. coli, maximum 7-day geometric mean	1413.6 #/100mL	≤ 1260 #/100mL	12%

Limits in force (161)

Parameter	Statistic	Limit	Months	Outfall
BOD, 5-day, 20 deg. C	30-day average	≤ 30 mg/L	all year	001
BOD, 5-day, 20 deg. C	maximum 7-day average	≤ 45 mg/L	all year	001
pH	minimum	≥ 6.5 SU	all year	001
pH	maximum	≤ 9 SU	all year	001
Solids, total suspended	30-day average	≤ 30 mg/L	all year	001
Solids, total suspended	maximum 7-day average	≤ 45 mg/L	all year	001
Nitrogen, ammonia total [as N]	30-day average	≤ 17 mg/L	Apr	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13 mg/L	Jan	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Feb	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Aug	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Jun	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	May	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Jul	001
Nitrogen, ammonia total [as N]	30-day average	≤ 17 mg/L	Mar	001
Nitrogen, ammonia total [as N]	30-day average	≤ 13 mg/L	Dec	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Oct	001
Nitrogen, ammonia total [as N]	30-day average	≤ 20 mg/L	Sep	001
Nitrogen, ammonia total [as N]	30-day average	≤ 17 mg/L	Nov	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 32 mg/L	Apr	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 23 mg/L	Jan	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 37 mg/L	Feb	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 65 mg/L	Aug	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 65 mg/L	Jun	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 44 mg/L	May	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 65 mg/L	Jul	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 31 mg/L	Mar	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 23 mg/L	Dec	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 46 mg/L	Oct	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 62 mg/L	Sep	001
Nitrogen, ammonia total [as N]	daily maximum	≤ 32 mg/L	Nov	001
Cyanide, weak acid, dissociable	daily maximum	report only (ug/L)	all year	001
Cyanide, weak acid, dissociable	rolling average	report only (ug/L)	all year	001
Cyanide, total [as CN]	daily maximum	report only (ug/L)	all year	001
Arsenic, total recoverable	30-day average	report only (ug/L)	all year	001
Arsenic, total recoverable	rolling average	report only (ug/L)	all year	001
Iron, total recoverable	30-day average	report only (ug/L)	all year	001
Iron, total recoverable	rolling average	report only (ug/L)	all year	001
Arsenic, total [as As]	daily maximum	report only (ug/L)	all year	001
Cadmium, total [as Cd]	daily maximum	report only (ug/L)	all year	001
Chromium, total [as Cr]	daily maximum	report only (ug/L)	all year	001
Copper, total [as Cu]	daily maximum	report only (ug/L)	all year	001
Lead, total [as Pb]	daily maximum	report only (ug/L)	all year	001
Molybdenum, total [as Mo]	daily maximum	report only (ug/L)	all year	001
Nickel, total [as Ni]	daily maximum	report only (ug/L)	all year	001
Silver, total [as Ag]	daily maximum	report only (ug/L)	all year	001
Zinc, total [as Zn]	daily maximum	report only (ug/L)	all year	001
Chromium, total recoverable	daily maximum	report only (ug/L)	all year	001
Molybdenum, total recoverable	daily maximum	report only (ug/L)	all year	001
Molybdenum, total recoverable	rolling average	report only (ug/L)	all year	001
Selenium, total [as Se]	daily maximum	report only (ug/L)	all year	001
Chromium, hexavalent dissolved [as Cr]	30-day average	report only (ug/L)	all year	001
Chromium, hexavalent dissolved [as Cr]	daily maximum	report only (ug/L)	all year	001
Zinc, potentially dissolved	30-day average	report only (ug/L)	all year	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Jan	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Feb	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Mar	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Apr	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	May	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Jun	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Jul	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Aug	001
Zinc, potentially dissolved	30-day average	≤ 268 ug/L	Sep	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Oct	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Nov	001
Zinc, potentially dissolved	30-day average	≤ 340 ug/L	Dec	001
Zinc, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Jan	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Feb	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Mar	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Apr	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	May	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Jun	001
Zinc, potentially dissolved	daily maximum	≤ 433 ug/L	Jul	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Aug	001
Zinc, potentially dissolved	daily maximum	≤ 315 ug/L	Sep	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Oct	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Nov	001
Zinc, potentially dissolved	daily maximum	≤ 493 ug/L	Dec	001
Silver, potentially dissolved	30-day average	report only (ug/L)	all year	001
Silver, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Copper, potentially dissolved	30-day average	report only (ug/L)	all year	001
Copper, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Copper, potentially dissolved	rolling average	report only (ug/L)	all year	001
Arsenic, potentially dissolved	daily maximum	report only (ug/L)	all year	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Jan	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Feb	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Mar	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Apr	001
Cadmium, potentially dissolvd	30-day average	≤ 1.2 ug/L	May	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Jun	001
Cadmium, potentially dissolvd	30-day average	≤ 1.4 ug/L	Jul	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Aug	001
Cadmium, potentially dissolvd	30-day average	≤ 1.1 ug/L	Sep	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Oct	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Nov	001
Cadmium, potentially dissolvd	30-day average	≤ 1.6 ug/L	Dec	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Jan	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Feb	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Mar	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Apr	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.4 ug/L	May	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Jun	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.7 ug/L	Jul	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Aug	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.2 ug/L	Sep	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Oct	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Nov	001
Cadmium, potentially dissolvd	daily maximum	≤ 1.9 ug/L	Dec	001
Cadmium, potentially dissolvd	rolling average	report only (ug/L)	all year	001
Cadmium, potentially dissolvd	rolling average	≤ 1 ug/L	all year	001
Chromium, trivalent, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Chromium, trivalent, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Lead, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Lead, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Lead, potentially dissolvd	rolling average	report only (ug/L)	all year	001
Manganese, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Manganese, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Manganese, potentially dissolvd	rolling average	report only (ug/L)	all year	001
Nickel, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Nickel, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Nickel, potentially dissolvd	rolling average	report only (ug/L)	all year	001
Selenium, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Selenium, potentially dissolvd	daily maximum	report only (ug/L)	all year	001
Uranium, potentially dissolvd	30-day average	report only (ug/L)	all year	001
Oil and grease	instantaneous maximum	≤ 10 mg/L	all year	001
Total phenols	daily maximum	report only (ug/L)	all year	001
Radium 226 + radium 228, total	30-day average	report only (pCi/L)	all year	001
Strontium 90, total	30-day average	report only (pCi/L)	all year	001
Cesium-134	30-day average	report only (pCi/L)	all year	001
Benzene	30-day average	report only (ug/L)	all year	001
Benzene	daily maximum	report only (ug/L)	all year	001
BTEX	daily maximum	report only (ug/L)	all year	001
BTEX	daily maximum	≤ 100 ug/L	all year	001
Flow, in conduit or thru treatment plant	30-day average	≤ 1.15 MGD	all year	001
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year	001
Chlorine, total residual	30-day average	≤ .34 mg/L	all year	001
Chlorine, total residual	instantaneous maximum	≤ .48 mg/L	all year	001
Mercury, total [low level]	30-day average	≤ .077 ug/L	all year	001
E. coli	30-day geometric mean	≤ 630 #/100mL	all year	001
E. coli	maximum 7-day geometric mean	≤ 1260 #/100mL	all year	001
Sulfide-hydrogen sulfide [undissociated]	30-day average	report only (mg/L)	all year	001
Nonylphenol	30-day average	report only (ug/L)	all year	001
Nonylphenol	daily maximum	report only (ug/L)	all year	001
Nonylphenol	rolling average	report only (ug/L)	all year	001
Thorium-230 + Thorium-232	30-day average	report only (pCi/L)	all year	001
Mercury, total [as Hg]	daily maximum	report only (ug/L)	all year	001
BOD, 5-day, percent removal	monthly average minimum	≥ 85 %	all year	001
Solids, suspended percent removal	monthly average minimum	≥ 85 %	all year	001
Oil and grease visual	instantaneous maximum	report only (abst=0;prst=1)	all year	001
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia	minimum value	≥ 100 %	all year	001
LC50 Static Renewal 96Hr Acute Pimephales promelas	minimum value	≥ 100 %	all year	001
Plant capacity fact. percent of capacity	30-day average	report only (%)	all year	300
Plant capacity fact. percent of capacity	30-day average	report only (%)	all year	300
BOD, 5-day, 20 deg. C	30-day average	report only (mg/L)	all year	300
BOD, 5-day, 20 deg. C	maximum 7-day average	report only (mg/L)	all year	300
BOD, 5-day, 20 deg. C	30-day average	report only (lb/d)	all year	300
BOD, 5-day, 20 deg. C	maximum 7-day average	report only (lb/d)	all year	300
Solids, total suspended	30-day average	report only (mg/L)	all year	300
Solids, total suspended	maximum 7-day average	report only (mg/L)	all year	300
Flow, in conduit or thru treatment plant	30-day average	report only (MGD)	all year	300
Flow, in conduit or thru treatment plant	daily maximum	report only (MGD)	all year	300

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/CO0021164 · MCP: https://passage-data.com/mcp