Poet Biorefining - Arthur, LLC — NPDES permit IA0081558: limits, due date and EPA's record

Industrial Organic Chemicals, Arthur, Iowa. NPDES permit IA0081558, in force until Aug 31, 2029. Last 12 months: no values over a limit. Source: EPA ECHO, Oct 22, 2026.

Limits in force (20)

Parameter	Statistic	Limit	Months	Outfall
pH	daily minimum	≥ 6.1 SU	all year	001
pH	daily maximum	≤ 9 SU	all year	001
Solids, total suspended	30-day average	≤ 30 mg/L	all year	001
Solids, total suspended	daily maximum	≤ 45 mg/L	all year	001
Solids, total suspended	30-day average	≤ 101 lb/d	all year	001
Solids, total suspended	daily maximum	≤ 152 lb/d	all year	001
pH	daily minimum	≥ 6.2 SU	all year	002
pH	daily maximum	≤ 9 SU	all year	002
Solids, total suspended	30-day average	≤ 30 mg/L	all year	002
Solids, total suspended	daily maximum	≤ 45 mg/L	all year	002
Solids, total suspended	30-day average	≤ 101 lb/d	all year	002
Solids, total suspended	daily maximum	≤ 152 lb/d	all year	002
Sulfate, total [as SO4]	30-day average	≤ 1751 mg/L	all year	002
Sulfate, total [as SO4]	daily maximum	≤ 1751 mg/L	all year	002
Sulfate, total [as SO4]	30-day average	≤ 10746 lb/d	all year	002
Sulfate, total [as SO4]	daily maximum	≤ 10746 lb/d	all year	002
Iron, total [as Fe]	30-day average	≤ 1.16 mg/L	all year	002
Iron, total [as Fe]	daily maximum	≤ 1.16 mg/L	all year	002
Iron, total [as Fe]	30-day average	≤ 7.14 lb/d	all year	002
Iron, total [as Fe]	daily maximum	≤ 7.14 lb/d	all year	002

How strict are these limits?

Your permit document is the final word. As JSON: /api/v1/permits/IA0081558 · MCP: https://passage-data.com/mcp