top of page

Here We Go Again: 8 Straight Days of Stench, H2S Exceedances - GASP *Again* Calls on ACHD for Update



Mon Valley friends beware, the stench is really bad today. In addition to starting off the day with one of the worst NowCast AQIs in the nation, concentrations of hydrogen sulfide (H2S, which has a nasty rotten-egg odor) are alarmingly high.


Actually, it’s been more than a week of stench for our neighbors in and downwind of the Mon Valley, home to one of the worst neighbors around, U.S. Steel: Today marks the eighth straight day of H2S concentrations that exceed Pennsylvania’s 24-hour-average standard.


Consider this: Allegheny County Health Department’s Liberty monitor has seen 89 exceedances of the state 24-hour H2S standard so far this year (through today), which puts Allegheny County solidly on track for 2023 being the worst year since 2017.


We are on pace for 101 exceedances at Liberty; there were 94 exceedances at Liberty in 2021 and 105 in 2017.

Or to put it another way, there have been 19 exceedances of the 24-hour standard at Liberty in the past 25 days (including today).


"U.S. Steel is currently paying who knows how much to run TV ads trying to convince residents about its commitment to improve local air quality in the Mon Valley," GASP Executive Director Patrick Campbell said. “If the company wanted to actually be a good neighbor, it would fix whatever issues are causing these days-long periods of malodor.”


Editor’s Note: ACHD on Thursday morning issued a Mon Valley Air Pollution Watch. You can learn more about those here.




bottom of page