Document ID: EPA-R10-OAR-2022-0115-0211
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2023-01-10T05:00Z

Fairbanks SIP Contingency Measure Emission Reductions
Emission reductions were estimated for DEC's contingency measure that requires the removal of all EPA-certified wood-burning stoves over 25 years old and replacement with certified stoves with PM emission ratings less than 2.0 g/hr.  The approach used to estimate the contingency measure emission reductions utilized data sources and methods consistent with other wood-burning control measure analysis within the SIP.  Key assumptions and elements are outlined below:

 Assumed the measure applies to cordwood stoves and fireplace inserts.
 Total and wood device-specific average episodic household energy use was estimated from the 2011-2015 Fairbanks Home Heating (HH) Survey (which is discussed at length in the SIP).
 The fraction of wood stoves/inserts over 25 years old was estimated from the HH Survey and found to be 19.1%.
 The fractions of certified stoves/inserts above and below the 2.0 g/hr rating within the nonattainment area and the ratio of PM emissions between the two subsets was estimated from DEC's 2013 Wood Tag survey (also discussed in the SIP).

Baseline and "after replacement" emissions were then calculated using the data/assumptions above for affected households (those with > 25-year old certified stoves) within the non-attainment area.  A compliance rate of 10% was estimated based on the frequency these older stoves/inserts would be identified and replaced through residential home resales.  According to data published in the Fairbanks Community Research Quarterly, the Fairbanks Borough averaged 1,215 home sales per year from 2017-2019, the most recent period of available data.  Accounting for the fraction that are re-sales (that trigger a compliance mechanism) and within the nonattainment area, along with the fraction of homes with > 25-year old wood stoves, yielded the estimated "compliance" rate of 10%.  This reflects a minimum, or base-level compliance rate that only triggers removal/replacement of > 25-year old certified stoves through real estate transactions.  

Based on this minimum estimated compliance rate, the contingency measure is expected to provide PM2.5 reductions of 0.01 tons/day (averaged over the modeling episodes) in its first year of implementation.  Reductions would also accumulate over time as the 25 year threshold targets a new year of older stoves in each successive calendar year.