Black Hills Energy

NPDES permit WY0096784 · Minor NON-POTW · effective, expires 2028-04-30 · EPA's file as of 2026-09-19

Check this month's numbers before you file
Watch this permit — $79 a month. Every Monday, from EPA's newest files: the next report due and when, whether EPA's file holds your last one, any change to this permit's limits or status, and the renewal date.

EPA's record, 2025-09-01 to 2026-08-31

0values over a limit
0required values missing, on 0 form(s)
0of 17 forms filed late

Last period with anything received: 2026-08-31.

Reporting

Reports are due about 28 days after each monitoring period ends (the most common figure among WY permits in EPA's filings — check your permit).

Limits in force (22)

OutfallParameterStatisticLimitMonths
001pHINST MIN >= 6.5 SU all year
001pHINST MAX <= 9 SU all year
001Solids, total suspendedDAILY MX <= 100 mg/L all year
001Solids, total suspendedMO AVG <= 30 mg/L all year
001Phosphorus, total [as P]DAILY MX report only all year
001Chromium, total [as Cr]DAILY MX report only all year
001Copper, total [as Cu]DAILY MX <= 1 mg/L all year
001Copper, total [as Cu]MO AVG <= 1 mg/L all year
001Iron, total [as Fe]DAILY MX <= 1 mg/L all year
001Iron, total [as Fe]MO AVG <= 1 mg/L all year
001Zinc, total [as Zn]DAILY MX <= 1 mg/L all year
001Zinc, total [as Zn]MO AVG <= 1 mg/L all year
001Aluminum, dissolved [as Al]DAILY MX <= 750 ug/L all year
001ChlorideDAILY MX <= .5 mg/L all year
001ChlorideMO AVG <= .2 mg/L all year
001DurationMO TOTAL report only all year
001Chlorine, total residualDAILY MX <= .019 mg/L all year
001FlowMO AVG report only all year
001FlowDAILY MX report only all year
001Produced water, oil and greaseDAILY MX <= 10 mg/L all year
001Pass/Fail Static 48Hr Acute Ceriodaphnia dubia4C <= 0 pass=0;fail=1 all year
001Pass/Fail Static 96 Hr Acute Pimephales Promelas9D <= 0 pass=0;fail=1 all year

Built from EPA's ECHO bulk files. EPA's file, not the permit document, is the source: read your permit. Check a report before you file it · All states