North Coast Unified Air Quality Management District (NCUAQMD)

NCUAQMD is the pollution control agency for the counties of Humboldt, Del Norte and Trinity. California’s ambient air quality standards classified North Coast as nonattainment for PM10 in Humboldt County only.

ERCs are available for five different pollutants:

Pollutant Significant Emission Rates
Nitrogen oxides (NOx) >40 tons/year
Reactive organic compounds (ROC) >40 tons/year
Sulfur oxides (SOx) >40 tons/year
Carbon monoxide (CO) >100 tons/year
PM10 >15 tons/year
PM2.5 >10 tons/year

That means if 100 tpy of NOx or ROC are emitted from a proposed new or modified major facility in an area classified as nonattainment for ozone, the facility must obtain 100 tpy of ERCs on-site to offset the increase in NOx or ROC emissions. However, if ERCs were generated 20 miles away from the new or modified major facility, 120 tpy of ERCs will be needed to offset the increases in emissions.

NCUAQMD may approve inter-pollutant offsets on a case-by-case basis. The applicant must be able to demonstrate that the emission increases from the new or modified source will result in a net air quality benefit to the district. NCUAQMD may impose offset ratios greater than the specified above and requires an EPA approval for the use of inter-pollutant offsets.