

 
The Renewable Fuel Standard (RFS): Waiver 
Authority and Modification of Volumes 
Updated August 3, 2020 
Congressional Research Service 
https://crsreports.congress.gov 
R44045 
 
  
 
The Renewable Fuel Standard (RFS): Waiver Authority and Modification of Volumes 
 
Summary 
The Clean Air Act requires that transportation fuels contain a minimum volume of renewable 
fuel. This Renewable Fuel Standard (RFS) was established by the Energy Policy Act of 2005 
(EPAct05; P.L. 109-58) and amended by the Energy Independence and Security Act of 2007 
(EISA; P.L. 110-140). The RFS includes scheduled volume mandates that grow each year 
(starting with 9 billion gallons in 2008 and ascending to 36 billion gallons in 2022). The U.S. 
Environmental Protection Agency (EPA), which is responsible for administering the RFS, 
determines the annual volume after 2022. Within the overall RFS, there are submandates for 
advanced biofuels, including cellulosic biofuel and biomass-based diesel. 
EPA has the authority to waive the RFS requirements, in whole or in part, if certain conditions 
outlined in statute prevail. More specifically, the statute identifies a general waiver and waivers 
for two types of advanced biofuel: cellulosic biofuel and biomass-based diesel. Statute requires 
EPA to announce the upcoming year’s standards by November 30 of the previous year, except for 
biomass-based diesel, which must be announced 14 months before the year for which the 
applicable volume is to apply. Further, the final section of the waiver provision—which some 
refer to as the “reset” section—requires a permanent modification of applicable volumes of the 
RFS if certain conditions are met (e.g., if the applicable volumes are reduced by at least 20% for 
two consecutive years or by at least 50% for a single year). The statute allows the modification of 
the applicable volumes to take place starting in 2016.  
In several instances, EPA has used, has proposed to use, or has been petitioned to use its waiver 
authority when implementing the RFS. In December 2019, EPA announced in its final rule for the 
2020 RFS that it was using the cellulosic biofuel waiver authority to reduce the cellulosic biofuel, 
advanced biofuel, and total renewable fuel volume requirements. EPA’s use of the cellulosic 
biofuel waiver authority is not new. EPA has repeatedly issued a waiver, reducing the volume 
required for cellulosic biofuel. For the 2014-2020 final rules, EPA has used the cellulosic biofuel 
waiver to also reduce the total advanced biofuel volume requirement. For various reasons (e.g., 
technology issues, financial support, policy uncertainty), the U.S. cellulosic biofuel industry has 
been unable, by a wide margin, to produce the volume amounts identified in statute.  
EPA also has the authority to “reset” the RFS. The 2019 final RFS program rule issued by EPA 
triggered the RFS “reset” section of the waiver provision for total renewable fuel. The reset was 
triggered in previous final rules for both advanced biofuel and cellulosic biofuel. It is unclear 
what impact the use of the reset by EPA will have on RFS standards for future years given that 
only two years remain that have statutory volume requirements—2021 and 2022. EPA has 
statutory authority to determine the volume amounts after 2022. 
At issue for Congress is the effectiveness of the RFS waiver authority and a potential 
programmatic reset. Congress may consider whether the waiver authority and the reset authority 
are sufficient options for EPA to address the statutory advanced biofuel volume shortfalls—
shortfalls that may have been more than what Congress envisioned when it expanded the RFS in 
2007. Another issue is how the Administration might apply the reset authority, and if it would 
contribute to uncertainty for industry, financiers, and other interested parties. 
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Contents 
Introduction ..................................................................................................................................... 1 
RFS Requirements ........................................................................................................................... 1 
RFS Annual Volume Announcement Deadlines .............................................................................. 2 
Current RFS Requirements.............................................................................................................. 3 
RFS Waiver Provisions .................................................................................................................... 4 
General Waiver .......................................................................................................................... 4 
Cellulosic Biofuel Waiver ......................................................................................................... 4 
Biomass-Based Diesel Waiver .................................................................................................. 5 
Modification of Applicable Volumes ........................................................................................ 5 
RFS Waiver Authority Use .............................................................................................................. 6 
RFS Waiver Impacts ........................................................................................................................ 6 
Impacts of RFS Modification of Applicable Volumes ..................................................................... 7 
 
Figures 
Figure 1. Scheduled Renewable Fuel Standard (RFS) Mandates Under EISA ............................... 2 
  
Tables 
Table 1. EISA and EPA RFS Requirements ..................................................................................... 3 
  
Contacts 
Author Information .......................................................................................................................... 8 
 
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Introduction 
The Renewable Fuel Standard (RFS) requires that the nation’s transportation fuel supply contain 
renewable fuels.1 This mandate—established in the Energy Policy Act of 2005 (EPAct05; P.L. 
109-58) and expanded in the Energy Independence and Security Act of 2007 (EISA; P.L. 110-
140)—requires the use of renewable fuel, although it does not explicitly require the production of 
that fuel. Obligated parties, such as refiners or importers of gasoline or diesel fuel, are responsible 
for complying with the RFS requirements. The U.S. Environmental Protection Agency (EPA) 
administers the mandate, which is an amendment to Clean Air Act (CAA) provisions governing 
the regulation of fuels.2 The statutory renewable fuel volume increases annually until 2022, with 
EPA determining the volume after 2022 within certain limitations. In general, EPA has the 
authority to waive the RFS requirements, in whole or in part, if certain conditions outlined in 
statute prevail. 
The RFS is a complex and highly technical policy initiative. It deals with multiple sectors of the 
economy and requires the use of some advanced renewable fuel production technologies that 
have yet to reach maturity. The RFS also incorporates thresholds for greenhouse gas emission 
reduction. This complexity is heightened by multiple stakeholders with differing perspectives on 
what the RFS should accomplish, how it should be implemented, and whether it should exist, 
which leads to debate about the RFS and its future. Congressional debate about the RFS is 
expected to continue with special attention to how EPA administers the program.3 As Congress 
continues its oversight of the RFS, it may be useful to understand the RFS waiver authority 
granted to EPA. This report discusses the waiver provisions of the RFS, including the 
modification-of-applicable-volumes (“reset”) section. 
RFS Requirements 
EPAct05 established a renewable fuel program (i.e., the RFS) requiring that transportation fuel 
sold or introduced into commerce in the United States, on an annual average basis, contain a 
specified amount of renewable fuel. The RFS mandate, as amended by EISA, calls for the 
consumption of 9 billion gallons of total renewable fuel in 2008, ascending to 36 billion gallons 
in 2022, with EPA determining the annual volume after 2022. The statute identifies four 
categories of renewable fuels that must be used to meet the mandate. These four categories can be 
aggregated into two major categories: unspecified biofuel (mainly cornstarch ethanol) and 
advanced biofuel (e.g., cellulosic biofuel, biomass-based diesel, and other advanced biofuels), 
shown in Figure 1.4 Over time, the growth in the RFS transitions from biofuels that, in practice, 
are made mostly from food and feed crops to biofuels made from nonfood and nonfeed crops. For 
instance, in 2022, the statute requires that advanced biofuels constitute close to 60% of the 36 
billion gallon mandate and unspecified biofuels constitute about 40%.  
                                                 
1 For more information on the Renewable Fuel Standard (RFS) and related issues, see CRS Report R43325, The 
Renewable Fuel Standard (RFS): An Overview, by Kelsi Bracmort. 
2 P.L. 109-58 (Title XV, Subtitle A, Section 1501) established the RFS under Clean Air Act Section 211(o); 42 U.S.C. 
§7545(o). P.L. 110-140 expanded the RFS, including the requirement of larger annual volumes and the addition of 
greenhouse gas accounting requirements. 
3 Legislation has been introduced in the 116th Congress that would modify or repeal the RFS. For example, see S. 
2873, S. 1840, H.R. 5113 (identical to S. 2873), H.R. 3427, and H.R. 3411.  
4 The unspecified biofuel volume requirement equates to the difference between the total renewable fuel category and 
the advanced biofuel category. 
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The Renewable Fuel Standard (RFS): Waiver Authority and Modification of Volumes 
 
Figure 1. Scheduled Renewable Fuel Standard (RFS) Mandates Under EISA 
 
Sources: Congressional Research Service (CRS) using mandates in the Energy Independence and Security Act of 
2007 (EISA; P.L. 110-140). 
RFS Annual Volume Announcement Deadlines 
Congress gave the EPA Administrator an annual deadline to determine and publish the renewable 
fuel obligations (i.e., final volume requirements). The EPA Administrator is required to announce 
the renewable fuel obligations (typically referred to as “set the standards”) by November 30 of 
the preceding year (e.g., under statute the 2021 standard is required to be finalized by November 
30, 2020).5 For biomass-based diesel, the statute specifies volumes for four years (2009-2012) 
and requires EPA to announce the remaining annual biomass-based diesel standards “14 months 
before the first year for which such applicable volume will apply” (e.g., the 2022 biomass-based 
diesel standard is required to be finalized by November 2020).6 The requirement that EPA 
announce the standard 14 months prior is scheduled to apply to the other renewable fuel 
categories for calendar years 2023 and onward. 
                                                 
5 42 U.S.C. §7545 (o)(3)(B)(i). 
6 42 U.S.C. §7545 (o)(2)(B)(ii).  
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Current RFS Requirements 
EPA issued the final 2020 standards (and the 2021 standard for biomass-based diesel) in 
December 2019.7 The RFS statutory requirements and the EPA requirements for 2014 through 
2020 are provided in Table 1.  
Table 1. EISA and EPA RFS Requirements 
(in billions of gallons) 
Unspecified 
Total 
Biofuel / Cap on 
Advanced Biofuel 
Renewable 
Conventional 
(cellulosic biofuel 
Year 
Fuel 
Biofuel 
component)a 
2014 Statutory 
18.15 
14.40 
 3.75 (1.750) 
2014 EPA Final 
16.28 
13.61 
 2.67 (0.033) 
2015 Statutory 
20.50 
15.00 
5.50 (3.000) 
2015 EPA Final 
16.93b 
14.05 
2.88 (0.123) 
2016 Statutory 
 22.25 
15.00 
7.25 (4.250) 
2016 EPA Final 
18.11b 
14.50 
3.61 (0.230) 
2017 Statutory 
24.00 
15.00 
9.00 (5.500) 
2017 EPA Final 
19.28 
15.00 
4.28 (0.311) 
2018 Statutory 
26.00 
15.00 
11.00 (7.000) 
2018 EPA Final 
19.29 
15.00 
4.29 (0.288) 
2019 Statutory 
28.00 
15.00 
13.00 (8.500) 
2019 EPA Final 
19.92 
15.00 
4.92 (0.418) 
2020 Statutory 
30.00 
15.00 
15.00 (10.50) 
2020 EPA Final 
20.09 
15.00 
5.09 (0.590) 
Sources: EISA (P.L. 110-140); 42 U.S.C. §7545(o); U.S. Environmental Protection Agency (EPA), “Renewable 
Fuel Standard Program: Standards for 2014, 2015, and 2016 and Biomass-Based Diesel Volume for 2017; Final 
Rule,” 80 Federal Register 239, December 14, 2015; EPA, “Renewable Fuel Standard Program: Standards for 2017 
and Biomass-Based Diesel Volume for 2018; Final Rule,” 81 Federal Register 89746, December 12, 2016; EPA, 
“Renewable Fuel Standard Program: Standards for 2018 and Biomass-Based Diesel Volume for 2019; Final Rule,” 
82 Federal Register 58486, December 12, 2017; EPA, “Renewable Fuel Standard Program: Standards for 2019 and 
Biomass-Based Diesel Volume for 2020; Final Rule,” 83 Federal Register 63704, December 11, 2018; U.S. 
Environmental Protection Agency, “Renewable Fuel Standard Program: Standards for 2020 and Biomass-Based 
Diesel Volume for 2021 and Other Changes,” 85 Federal Register 7016, February 6, 2020. 
Notes: All volumes are ethanol equivalent. Ethanol equivalent is the amount of fuel needed to give the same 
amount of energy as one gallon of ethanol.  
a.  Advanced biofuels can include cellulosic biofuel, biomass-based diesel, biogas, butanol, and others. Advanced 
biofuel is defined as renewable fuel, other than cornstarch ethanol, that has lifecycle greenhouse gas 
emissions that are at least 50% lower than the emissions from comparable petroleum products.  
b.  The D.C. Circuit Court vacated EPA’s 2016 total renewable fuel volume requirement and remanded the 
2015 final rule to EPA for reconsideration. Americans for Clean Energy v. EPA, No. 16-1005, 2017 U.S. App. 
LEXIS 13692, at *4-5 (D.C. Cir. July 28, 2017).  
                                                 
7 U.S. Environmental Protection Agency, “Renewable Fuel Standard Program: Standards for 2020 and Biomass-Based 
Diesel Volume for 2021 and Other Changes,” 85 Federal Register 7016, February 6, 2020. 
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RFS Waiver Provisions 
The statute for the RFS contains a waiver section with a set of waiver provisions.8 The provisions 
describe three separate waivers—a general waiver, a cellulosic biofuel waiver, and a biomass-
based diesel waiver—that the EPA Administrator may use to waive, with certain stipulations for 
certain waivers, the volume of renewable fuel mandated by statute. The waivers referred to in this 
report should not be confused with small refinery exemptions.9 Additionally, there is a provision 
for the modification of applicable volumes (i.e., a “reset”) that the EPA Administrator may use. 
The waivers and the modification of applicable volumes are described in further detail in the 
following sections of this report. 
General Waiver 
The RFS statute gives the EPA Administrator the authority to waive the RFS requirements, in 
whole or in part, “by reducing the national quantity of renewable fuel required” if  
  implementation of the requirement would severely harm the economy or 
environment of a state, a region, or the United States, or 
  domestic renewable fuel supply is inadequate to meet the mandate.10  
The Administrator may issue the general waiver at his or her discretion or if petitioned by a state 
or any person subject to the RFS requirements (e.g., refiners and importers). Prior to making a 
decision, the Administrator is required to consult with the Secretary of Agriculture and Secretary 
of Energy and to allow for public notice and the opportunity for comment. In those instances in 
which the Administrator receives a petition for a waiver, the Administrator has 90 days after 
receipt of the petition to approve or disapprove it.11 If a general waiver is issued, it expires after 
one year, unless the Administrator renews the waiver.12  
Cellulosic Biofuel Waiver 
The RFS statute obligates the EPA Administrator to reduce the cellulosic biofuel mandate when 
the projected production capacity for a given year is less than the volume required in the statute.13 
The law does not require the EPA Administrator to consult with the Secretary of Agriculture or 
the Secretary of Energy when issuing a cellulosic biofuel waiver, or to give public notice and 
opportunity for comment. However, the Administrator must use the projected volume estimate 
from the U.S. Energy Information Administration provided under the applicable percentages 
section of the statute.14 In prior waiver determinations, EPA has provided opportunity for public 
                                                 
8 42 U.S.C. §7545(o)(7). 
9 Small refiners may petition the EPA Administrator for an exemption from the RFS mandate if they can prove 
compliance would subject them to disproportionate economic hardship. For more information on small refinery 
exemptions, see 42 U.S.C. §7545(o)(9) or CRS Report R46244, The Renewable Fuel Standard (RFS): Frequently 
Asked Questions About Small Refinery Exemptions (SREs), by Kelsi Bracmort. 
10 42 U.S.C. §7545(o)(7)(A). 
11 Information regarding petitions to waive the RFS requirements is available at the EPA Requests for Volume 
Requirement Waiver under the Renewable Fuel Standard Program website, https://www.epa.gov/renewable-fuel-
standard-program/requests-volume-requirement-waiver-under-renewable-fuel-standard.  
12 42 U.S.C. §7545(o)(7)(C). 
13 42 U.S.C. §7545(o)(7)(D). 
14 42 U.S.C. §7545(o)(3)(A). 
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comment.15 The Administrator must set the new required amount at the “projected available 
volume during that calendar year” by November 30 of the preceding year. Should the 
Administrator reduce the cellulosic biofuel volume, the Administrator also may reduce the 
volumes of advanced biofuel and total renewable fuel by the same or lesser volume. When the 
Administrator issues a cellulosic biofuel waiver, the Administrator must offer cellulosic biofuel 
waiver credits for obligated parties to purchase for that compliance year in lieu of using actual 
cellulosic biofuel.16 
Biomass-Based Diesel Waiver 
The RFS statutory provisions give the EPA Administrator authority to reduce the amount of 
biomass-based diesel required for up to 60 days if the Administrator determines that there are 
significant market circumstances (including feedstock disruptions) “that would make the price of 
biomass-based diesel fuel increase significantly.”17 If these market circumstances continue past 
the initial 60-day period, the Administrator may issue another waiver for an additional 60 days. 
The Administrator is to consult with the Secretaries of Energy and Agriculture prior to issuing 
such a waiver. If the Administrator issues a biomass-based diesel waiver, the Administrator also 
may reduce the volumes of advanced biofuel and renewable fuel by the same or lesser volume. As 
of July 2020, EPA has not used the biomass-based diesel waiver authority. 
Modification of Applicable Volumes 
The last provision of the waiver section is the modification of applicable volumes provision, 
referred to by some as the “reset” provision for the RFS.18 This provision requires that the EPA 
Administrator modify the applicable volumes of the RFS in future years starting in 2016 if certain 
conditions are met. Specifically, it provides that, starting in 2016, the EPA Administrator shall 
modify the applicable volumes of the RFS for subsequent years if the Administrator waives the 
renewable fuel mandate, the advanced biofuel mandate, the cellulosic biofuel mandate, or the 
biomass-based diesel mandate by at least 20% for two consecutive years or by at least 50% for a 
single year. This reset section does not state what the modified amount must be. Rather, it 
                                                 
15 For example, see U.S. Environmental Protection Agency, Renewable Fuel Standard Program - Standards for 2020 
and Biomass-Based Diesel Volume for 2021 and Other Changes: Response to Comments, EPA-420-R-19-018, 
December 2019, pp. 20-23. Additionally, when conducting its cellulosic biofuel volume assessment for the coming 
year, EPA has consulted with EIA and industry. For example, for the 2014 cellulosic biofuel volume assessment, EPA 
reports it “spoke with representatives of each company to discuss cellulosic biofuel target production levels for 2014” 
and that “[t]hroughout this process EPA has been in contact with EIA to discuss relevant information.” U.S. 
Environmental Protection Agency, “2014 Standards for the Renewable Fuel Standard Program; Proposed Rule,” 78 
Federal Register 71739, November 29, 2013. 
16 EPA reports that “[t]hese credits can then be used by obligated parties to comply with the cellulosic biofuel volume 
obligation in lieu of RINs [Renewable Identification Numbers] generated with the production of the cellulosic biofuel. 
Cellulosic biofuel waiver credits are for obligated parties who do not acquire sufficient RINs for their cellulosic biofuel 
RVO [Renewable Volume Obligation] in a given compliance year.” U.S. Environmental Protection Agency, What Is 
the Purpose of a Cellulosic Biofuel Waiver Credit? https://www.epa.gov/fuels-registration-reporting-and-compliance-
help/what-purpose-cellulosic-biofuel-waiver-credit. The formula to calculate the price of these credits is in statute. For 
more information on cellulosic waiver credits, see U.S. Environmental Protection Agency, Cellulosic Waiver Credits 
under the Renewable Fuel Standard Program, April 7, 2020, https://www.epa.gov/renewable-fuel-standard-program/
cellulosic-waiver-credits-under-renewable-fuel-standard-program. For more information on cellulosic biofuels and the 
RFS, see CRS Report R41106, The Renewable Fuel Standard (RFS): Cellulosic Biofuels, by Kelsi Bracmort. 
17 42 U.S.C. §7545(o)(7)(E). For more information on biodiesel, see CRS Report R41282, Agriculture-Based Biofuels: 
Overview and Emerging Issues, by Mark A. McMinimy. 
18 42 U.S.C. §7545(o)(7)(F). 
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requires that the Administrator determine the applicable volumes—in coordination with the 
Secretaries of Energy and Agriculture—based on a review of program implementation thus far 
and an analysis of certain factors (e.g., the impact of the production and use of renewable fuels on 
the environment).19 
RFS Waiver Authority Use 
Since 2010, EPA has repeatedly used its cellulosic biofuel waiver authority to reduce the 
cellulosic biofuel volume required, and, since 2014, to also reduce both the advanced biofuel and 
total renewable fuel volume required.20 In December 2019, EPA announced that it used the 
cellulosic biofuel waiver to reduce the applicable total renewable fuel, advanced biofuel, and 
cellulosic biofuel volume requirements for 2020.21 According to the agency, “the 15.0 billion 
gallons specified in the statute for advanced biofuel cannot be reached in 2020 … primarily due 
to the expected continued shortfall in cellulosic biofuel.…”22 The Administrator has not issued a 
biomass-based diesel waiver.  
To date, EPA has only exercised the general waiver authority once to reduce the total renewable 
fuel volumes for 2014, 2015, and 2016, which the U.S. Court of Appeals for the D.C. Circuit 
subsequently vacated after concluding that EPA’s interpretation of “inadequate domestic supply” 
was not a permissible one.23 In that rule, EPA had interpreted the general waiver provision as 
allowing the agency to reduce all or any of the four renewable fuel volume requirements (i.e., 
total renewable fuel, advanced biofuels, biomass-based diesel fuel, or cellulosic biofuel) in whole 
or in part.24 In notices denying petitions for waivers, EPA has taken the position that any waiver 
must be nationwide in scope (i.e., reduce the statutory volumes nationwide).25 However, EPA has 
not codified this position in its regulations and no court has reviewed this interpretation. The 
general waiver authority has not been fully exercised; thus, it is not clear if only the total 
renewable fuel category can be reduced or if any of the renewable fuel categories (e.g., advanced 
biofuel) can be reduced. 
RFS Waiver Impacts 
Waiver authority is intended, in part, to assist EPA with implementation of the RFS.26 One of 
EPA’s program tasks is to use the waiver authority, when required, to determine the annual final 
                                                 
19 The Administrator is directed to promulgate a rule that modifies the applicable volumes in compliance with 42 
U.S.C. §7545(o)(2)(B)(ii). 
20 A list of volume reductions from 2010 to the present is available in Table 1 of CRS Report R43325, The Renewable 
Fuel Standard (RFS): An Overview, by Kelsi Bracmort.  
21 U.S. Environmental Protection Agency, “Renewable Fuel Standard Program: Standards for 2020 and Biomass-Based 
Diesel Volume for 2021 and Other Changes,” 85 Federal Register 7016, February 6, 2020. 
22 Ibid. 
23 Americans for Clean Energy v. EPA, 864 F.3d 691, 710-13 (D.C. Cir. 2017). 
24 80 Federal Register 77420, 77435 (Dec. 14, 2015). The rule was subsequently vacated by Americans for Clean 
Energy v. EPA. 864 F.3d 691, 710-13 (D.C. Cir. 2017). 
25 See, e.g., 73 Federal Register 47168, 47172 (Aug. 13, 2008); 77 Federal Register 70752, 70756 (Nov. 27, 2012). 
26 EPA reports that “… Congress also recognized that under certain circumstances it would be appropriate for EPA to 
set volume requirements at a lower level than reflected in the statutory volume targets, and thus provided waiver 
provisions in CAA section 211(o)(7).” U.S. Environmental Protection Agency, “Renewable Fuel Standard Program: 
Standards for 2020 and Biomass-Based Diesel Volume for 2021 and Other Changes,” 85 Federal Register 7020, 
February 6, 2020. 
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standard, and to announce that final standard by the statutory deadline. The challenge of 
projecting advanced biofuel production, pressure from some stakeholders, and other factors may 
have contributed to past delays (during the 2012-2015 timeframe) in issuing final standards under 
the waiver authority.27 Such delays could lead to difficulty for obligated parties who have to 
demonstrate program compliance and for renewable fuel producers who are interested in 
producing the required fuel. For 2016 through 2020, EPA has generally issued the final rule 
according to the statutory schedule. 
There are three stakeholders that generally have had distinct views about the impacts of the 
waiver authority: the advanced biofuel industry, the conventional biofuel industry, and the 
petroleum industry. Some advanced biofuel advocates assert that issuing waivers, in conjunction 
with other factors, could weaken confidence in renewable fuel markets and the chosen 
technologies, specifically cellulosic biofuel.28 Advanced biofuel, particularly cellulosic biofuels, 
have not been produced at the levels called for in the statutory provisions by relatively large 
margins.  
Some conventional biofuel advocates have not always agreed with EPA’s proposals to use the 
waiver authority to reduce conventional biofuel volumes.29 Conventional biofuel production has 
remained in line with what the statutory provisions require.  
Some in the petroleum industry assert that the waiver authority can be used as an option to 
address the “blend wall,” or, the maximum ethanol limit that would serve to avoid causing 
damage to many engines, fuel systems, and fueling infrastructure of vehicles.30 
While perspectives about EPA’s use of the waiver authority vary among stakeholders, the waivers 
have provided EPA with the flexibility to establish volume requirements that have been attained.  
Impacts of RFS Modification of 
Applicable Volumes 
The 2019 final rule triggered the “reset” (i.e., the modification-of-applicable-volumes provision 
of the RFS) for total renewable fuel. Previous final rules had already triggered a reset for both 
advanced biofuels and cellulosic biofuels.31 The Office of Management and Budget (OMB) 
                                                 
27 For a list of final rule release dates for the RFS, see Table 1 in CRS Report R43325, The Renewable Fuel Standard 
(RFS): An Overview, by Kelsi Bracmort. For an explanation of some of the challenges with cellulosic biofuel 
projection, see CRS Report R41106, The Renewable Fuel Standard (RFS): Cellulosic Biofuels, by Kelsi Bracmort. 
Discussions—with input from elected officials, the oil and gas sector, the agricultural sector, the environmental 
community, and others—regarding the RFS have been ongoing since its expansion. For example, see Humeyra Pamuk 
and Jarrett Renshaw, “EPA Chief Defends Biofuel Waivers in Meeting with Farm Senators: Sources,” Reuters, July 30, 
2019, or Robert Z. Lawrence, How Good Politics Results in Bad Policy: The Case of Biofuel Mandates, Harvard 
Kennedy School, Belfer Center for Science and International Affairs, September 2010. 
28 Advanced Ethanol Council, “33 Advanced Biofuel Companies Ask President Obama to Reconsider the Proposed 
RFS Rule for 2014,” press release, May 16, 2014; Advanced Ethanol Council, “AEC, BIO Joint Letter to White House 
over Proposed 2014 RFS Volumetric Blending Requirements,” October 29, 2013. 
29 Renewable Fuels Association, “EPA’s Draft 2017 RFS Rule Relies on Illegal Interpretation of Waiver Authority,” 
press release, May 18, 2016. 
30 American Petroleum Institute, “Court Decision on EPA RFS Waiver Underscores Need for Legislative RFS 
Reform,” press release, July 28, 2017. 
31 For a discussion of stakeholder comments about the reset and EPA’s response to the stakeholders, see U.S. 
Environmental Protection Agency, Renewable Fuel Standards for 2014, 2015 and 2016, and the Biomass-Based 
Volume for 2017: Response to Comments, EPA-420-R-15-024, November 2015, pp. 811-819, https://nepis.epa.gov/
Exe/ZyPDF.cgi?Dockey=P100NOLJ.pdf. 
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reported in fall of 2019 that “EPA is proposing a rulemaking that will propose modifying the 
applicable volumes targets for cellulosic biofuel, advanced biofuel, and total renewable fuel for 
the years 2020 to 2022.”32 It is not clear when or how EPA may carry out this action.  
The Administrator has the discretion to set the modified amounts.33 Depending on how the reset is 
applied, there could be interest in its impact on public and private investment for renewable fuels. 
There might also be interest in the reset’s potential impact on the transition of the program from 
mostly conventional biofuel to mostly advanced biofuel by 2022. Additionally, there may be 
interest about whether a reset could address the concerns expressed by some obligated parties 
(i.e., refiners) about high compliance costs. Going forward, reset implementation could have 
implications for the entire fuel industry, given the potential for EPA to reduce the applicable 
volumes or maintain ambitious targets. 
 
Author Information 
 
Kelsi Bracmort 
   
Specialist in Natural Resources and Energy Policy 
    
 
 
Disclaimer 
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan 
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32 U.S. Environmental Protection Agency, Renewable Fuel Standard Program: Modification of Statutory Volume 
Targets, RIN: 2060-AU28, 2019, https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=201910&RIN=2060-
AU28.  
33 The Administrator may do so based on a review of program implementation and an analysis of certain factors, among 
other things. 
Congressional Research Service  
R44045 · VERSION 27 · UPDATED 
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