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What materials from non-federal forestlands meet the definition of renewable biomass in RFS?

Slash and pre-commercial thinnings from non-federal forestland that is not ecologically sensitive forestland qualify as renewable biomass for purposes of RFS.

Slash is defined in 40 CFR 80.1401 as the residue, including treetops, branches and bark, left on the ground after logging or accumulating as a result of a storm, fire, delimbing or other similar disturbance. EPA interprets slash as being the residue that would typically be left on the ground after logging or a disturbance were it not for RFS. We acknowledge that the demand for such material may increase due to increased demand for feedstocks that meet the definition of renewable biomass for use in renewable fuel production. We also acknowledge that to meet this demand, logging techniques on non-federal forestland may be altered in order to collect residue in the most efficient and economical way, such as leaving waste treetops intact on merchantable trees until they have been removed from the forest. We believe that the intent of the regulatory definition may be met by considering slash to include what was traditionally considered waste, and was typically left on the ground at the site of timber harvesting prior to the RFS program, whether or not efficient harvesting practices continue to lead to that result. Slash does not include pulpwood from the actual sawtimber trees, and only includes pulpwood from sawtimber tree residues (treetops, branches and bark).

The term pre-commercial thinnings is defined in 40 CFR 80.1401 as trees, including unhealthy or diseased trees, removed to reduce stocking to concentrate growth on more desirable, healthy trees, or other vegetative materials that is removed to promote tree growth. EPA interprets pre-commercial thinnings to include all thinnings removed to improve growth and quality in the remaining healthy trees in the stand, provided substantial stock remains in the stand. Thus, unmerchantable trees removed during a clear-cut would not be considered pre-commercial thinnings because the term thinning requires that substantial stock remains in the stand. 6

Furthermore, those trees remaining in the stand after a pre-commercial thinning cannot generally be considered pre-commercial thinnings at a later date. Pre-commercial thinnings that meet these criteria are considered renewable biomass regardless of the timing of the thinning process (whether the thinning is conducted before a commercial harvest or during a selective commercial harvest of a portion of the trees in a stand for purposes other than renewable fuel feedstock production) or the diameter of the thinned trees. 40 CFR 80.1401 also requires slash and pre-commercial thinnings must be harvested from non-federal forestland (including forestland belonging to an Indian tribe or an Indian individual, that are held in trust by the United States or subject to a restriction against alienation imposed by the United States) that is not ecologically sensitive forestland. Forestland is defined in 40 CFR 80.1401, in relevant part here, as generally undeveloped land covering a minimum area of 1 acre upon which the primary vegetative species are trees, including land that formerly had such tree cover and that will be regenerated and tree plantations. Ecologically sensitive forestland includes ecological communities in the U.S. with Natural Heritage Programs global ranking of G1 or G2, or with a State ranking of S1, S2, or S3 and old growth and late successional forestland which is characterized by trees at least 200 years old.

If woody biomass is harvested in a manner consistent with the above interpretations, then it would qualify as slash and pre-commercial thinnings, and would meet the RFS definition of renewable biomass. The woody biomass would not lose its status as renewable biomass as a result of being subject to an additional processing step to extract the components that will be used for manufacturing other wood products, such as paper or building materials. However, EPA would only consider the biogenic portion of the waste from the processing to be slash and pre-commercial thinnings. To the extent that the slash and pre-commercial thinnings are mixed with chemicals or other materials during processing, the renewable fuel producer may only generate RINs for the fraction of renewable fuel made from the portion of the waste mixture that is actually biogenic (determined using the procedures described in ASTM test method D-6866, See 40 CFR 80.1426(f)(9)) and must be traced back to feedstocks meeting the definition of renewable biomass. Furthermore, cellulosic biofuel RINs may only be generated for the portion of the fuel that is made from feedstocks that both meets the renewable biomass requirements and consists of cellulose, hemi-cellulose or lignin.

Any producer using these types of feedstocks must also meet the relevant renewable biomass recordkeeping and reporting requirements in 40 CFR 80.1451 and 80.1454 to demonstrate that their feedstock meets the renewable biomass definitions, as well as all other applicable requirements in 40 CFR Part 80, Subpart M.