EPA Air · stack tests by county and year
Air-emissions stack tests in North Slope County, Alaska, 2025
- 21Stack tests
A stack test measures what a source actually emits, at the stack, against the limit in its permit. Each row below is one stack test recorded against a source in North Slope County, Alaska during 2025. A facility can appear several times: this is the year’s record of what happened, not a list of places. The sources themselves are on the North Slope County facility page.
North Slope County, Alaska, 2025
Air-emissions stack tests in North Slope County, other years
Air-emissions stack tests recorded in North Slope County, Alaska, 2025
| Date | Facility | Kind | Agency |
|---|---|---|---|
| 2025-12-13 | HILCORP ALASKA, LLC / PRUDHOE SEAWATER TREATMENT PLANT | Pass | State |
| 2025-12-13 | HILCORP ALASKA, LLC / PRUDHOE SEAWATER TREATMENT PLANT | Pass | State |
| 2025-12-13 | HILCORP ALASKA, LLC / PRUDHOE SEAWATER TREATMENT PLANT | Pass | State |
| 2025-12-13 | HILCORP ALASKA, LLC / PRUDHOE SEAWATER TREATMENT PLANT | Pass | State |
| 2025-10-21 | HILCORP ALASKA, LLC / GATHERING CENTER #2 (GC 2) | Pass | State |
| 2025-10-21 | HILCORP ALASKA, LLC / GATHERING CENTER #2 (GC 2) | Pass | State |
| 2025-10-19 | HILCORP ALASKA, LLC / MILNE POINT PRODUCTION FACILITY (MPU) | Fail | State |
| 2025-09-05 | HILCORP ALASKA, LLC / CENTRAL GAS FACILITY (CGF) — high-priority violation on file | Pass | State |
| 2025-08-20 | HILCORP ALASKA, LLC / MILNE POINT L-PAD | Pass | State |
| 2025-05-14 | HILCORP ALASKA, LLC / LISBURNE PRODUCTION CENTER (LPC) | Pass | State |
| 2025-05-14 | HILCORP ALASKA, LLC / LISBURNE PRODUCTION CENTER (LPC) | Pass | State |
| 2025-05-07 | ALYESKA PIPELINE SERVICE COMPANY / PS #01, TAPS PUMP STATION | Pass | State |
| 2025-05-07 | ALYESKA PIPELINE SERVICE COMPANY / PS #01, TAPS PUMP STATION | Pass | State |
| 2025-04-28 | HILCORP ALASKA, LLC / NORTHSTAR PRODUCTION FACILITY (NOR) | Pass | State |
| 2025-04-28 | HILCORP ALASKA, LLC / NORTHSTAR PRODUCTION FACILITY (NOR) | Pass | State |
| 2025-04-26 | HILCORP ALASKA, LLC / NORTHSTAR PRODUCTION FACILITY (NOR) | Pass | State |
| 2025-04-13 | HILCORP ALASKA, LLC / POINT THOMSON PRODUCTION FACILITY — high-priority violation on file | Fail | State |
| 2025-04-13 | HILCORP ALASKA, LLC / POINT THOMSON PRODUCTION FACILITY — high-priority violation on file | Fail | State |
| 2025-04-12 | HILCORP ALASKA, LLC / POINT THOMSON PRODUCTION FACILITY — high-priority violation on file | Fail | State |
| 2025-04-12 | HILCORP ALASKA, LLC / POINT THOMSON PRODUCTION FACILITY — high-priority violation on file | Fail | State |
| 2025-03-04 | HILCORP ALASKA, LLC / NIKAITCHUQ DEVELOPMENT | Pass | State |
Dates as filed by the agency that recorded the stack test. Figures from EPA’s ICIS-AIR download.