Passage Data · Check a report · Use it from your AI

City of Helena

Sewage treatment plant, Helena, Montana. NPDES permit MT0028720, in force until Jun 30, 2027. Last 12 months: no values over a limit, 1 of 16 reports late. Source: EPA ECHO, Oct 22, 2026.

Reports due
About 28 days after each period: form A monthly (24 values), form Q quarterly (1 value)
Renewal application due
Jan 1, 2027 · 180 days before expiry; your permit may set another date
Last report on file
September 2026
Oct 2024 – Sep 2025
0 values over a limit, 0 required values missing, 1 of 16 reports late

Limits in force (25)

ParameterStatisticLimitMonths
Flow ratemonthly averagereport only (MGD)all year
Flow ratemonthly averagereport only (MGD)all year
pHdaily minimum≥ 6 SUall year
pHdaily maximum≤ 9 SUall year
Solids, total suspendedmonthly average≤ 30 mg/Lall year
Solids, total suspendeddaily maximum≤ 45 mg/Lall year
Solids, total suspendedmonthly average≤ 80 lb/dall year
Hardness, total [as CaCO3]single grab samplereport only (mg/L)all year
Arsenic, total recoverablemonthly average≤ 10 ug/Lall year
Arsenic, total recoverabledaily maximum≤ 10 ug/Lall year
Arsenic, total recoverablemonthly averagereport only (ug/L)all year
Zinc, total recoverablemonthly average≤ 40 ug/Lall year
Zinc, total recoverabledaily maximum≤ 80 ug/Lall year
Zinc, total recoverablemonthly averagereport only (ug/L)all year
Aluminum, dissolved [as Al]monthly average≤ 64 ug/Lall year
Aluminum, dissolved [as Al]daily maximum≤ 158 ug/Lall year
Cadmium, total recoverablemonthly average≤ .14 ug/Lall year
Cadmium, total recoverabledaily maximum≤ .35 ug/Lall year
Cadmium, total recoverablemonthly averagereport only (ug/L)all year
Copper, total recoverablemonthly average≤ 3.1 ug/Lall year
Copper, total recoverabledaily maximum≤ 8.9 ug/Lall year
Copper, total recoverablemonthly averagereport only (ug/L)all year
Durationtotalreport only (d)all year
Chlorine, total residualmonthly averagereport only (mg/L)all year
Chlorine, total residualdaily maximum≤ .09999 mg/Lall year

How strict are these limits?

Cited limits by parameter: Montana's rules and the federal ones.

Check this month's numbers Email me before each report is due

· Save this facility as a site · Superfund sites nearby · Your permits on one board

On EPA ECHO: Facility report · DMR history

Your permit document is the final word. As JSON: /api/v1/permits/MT0028720 · MCP: https://passage-data.com/mcp