567—32.4 (455B) Exceedance of the health effects standard (HES) for hydrogen sulfide. The health effects standard for hydrogen sulfide is exceeded at a monitoring site when the daily maximum one-hour average concentration exceeds 30 ppb more than seven times per year. The department shall develop plans and programs to abate hydrogen sulfide emissions from animal feeding operations if hydrogen sulfide levels measured at a separated location exceed the health effects standard for hydrogen sulfide.