ASTM D2622-10, entitled "Standard Test Method for Sulfur in Petroleum Products by Wavelength Dispersive X-Ray Fluorescence Spectrometry"
Sulfur (gasoline)
ASTM D5453-09, entitled, "Standard Test Method for Determination of Total Sulfur in Light Hydrocarbons, Spark Ignition Engine Fuel, Diesel Engine Fuel, and Engine Oil by Ultraviolet Fluorescence"
Sulfur (500 ppm sulfur diesel)
ASTM D5453-09, entitled, "Standard Test Method for Determination of Total Sulfur in Light Hydrocarbons, Spark Ignition Engine Fuel, Diesel Engine Fuel, and Engine Oil by Ultraviolet Fluorescence"
Sulfur (gasoline)
ASTM D3120-08, entitled, "Standard Test Method for Trace Quantities of Sulfur in Light Petroleum Hydrocarbons by Oxidative Microcoulometry"
Sulfur (500 ppm sulfur diesel)
ASTM D4294-10, entitled, "Standard Test Method for Sulfur in Petroleum Products by Energy Dispersive Xray Fluorescence Spectrometry"
Sulfur (butane)
ASTM D6667-10, entitled, "Standard Test Method for Determination of Total Volatile Sulfur in Gaseous Hydrocarbons and Liquefied Petroleum Gases by Ultraviolet Fluorescence"
Sulfur (butane)
ASTM D4468-85(2006), entitled, "Standard Test Method for Total Sulfur in Gaseous Fuels by Hydrogenolysis and Rateometric Colorimetry"
Sulfur (butane)
ASTM D3246-11, entitled, "Standard Test Method for Sulfur in Petroleum Gas by Oxidative Microcoulometry"
Oxygen content (gasoline)
ASTM D5599-00(2010), entitled, "Standard Test Method for Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen Selective Flame Ionization Detection"
Oxygen content (gasoline)
ASTM D4815-09, entitled "Standard Test Method for Determination of MTBE, ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C1 to C4 Alcohols in Gasoline by Gas Chromatography"
Olefins (gasoline)
ASTM D1319-10, entitled "Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption"
Olefins (gasoline)
ASTM D6550-10, entitled, "Standard Test Method for the Determination of Olefin Content of Gasolines by Supercritical-Fluid Chromatography"
Aromatics (gasoline and diesel)
ASTM D1319-10, entitled "Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Absorption," for diesel fuel, this method is the designated test method; for gasoline, this method is an alternative test method and if used as an alternative method, its results must be correlated to ASTM D5769.
Aromatics (gasoline)
ASTM D5769-10, entitled, "Standard Test Method for Determination of Benzene, Toluene, and Total Aromatics in Finished Gasolines by Gas Chromatography/Mass Spectrometry"
Benzene (gasoline)
ASTM D3606-10, entitled, "Standard Test Method for Determination of Benzene and Toluene in Finished Motor and Aviation Gasoline by Gas Chromatography"
Distillation (gasoline)
ASTM D86-11a, entitled, "Standard Test Method for Distillation of Petroleum Products at Atmospheric Pressure"
Reid Vapor Pressure (gasoline)
ASTM D5191-10b, entitled, "Standard Test Method for Vapor Pressure of Petroleum Products (Mini-Method)"
Cetane Index (diesel)
ASTM D976-06(2011), entitled, "Standard Test Method for Calculated Cetane Index of Distillate Fuels"
Manual Sampling of Petroleum and Petroleum Products
ASTM D4057-06(Reapproved 2011), entitled, "Standard Practice for Manual Sampling of Petroleum and Petroleum Products"
Automatic Sampling of Petroleum and Petroleum Products
ASTM D4177-95(Reapproved 2010), entitled, "Standard Practice for Automatic Sampling of Petroleum and Petroleum Products"
RVP Sampling for Fuels
ASTM D5842-04(Reapproved 2009), entitled, "Standard Practice for Sampling and Handling of Fuels for Volatility Measurement"
Composite Sampling of Petroleum and Petroleum Products
ASTM D5854-96(Reapproved 2010), entitled, "Standard Practice for Mixing and Handling of Liquid 	Samples of Petroleum and Petroleum Products"

        Amendments Related to Downstream Blending
Today's proposed rule also clarifies the list of products that are not to be included in a refinery's or importer's compliance determination under §80.1240.  Refiners and importers are currently required under §80.1235(b)(2) to exclude oxygenate added to finished gasoline, RBOB or CBOB downstream of either the refinery that produced the gasoline or the import facility where the gasoline was imported.  This conflicts with EPA's intended approach in §80.1238(b), which allows refiners and importers to include oxygenate blended downstream of a refinery or import facility in their annual average benzene calculation, provided the refiner or importer meets certain requirements.  We are proposing changes that would allow refiners and importers to include oxygenate blended downstream of their facility and that would make these related sections consistent.
        Amendments for Previously Certified Gasoline
For benzene, we would also provide flexibility for refiners and importers by providing an alternative allowing them to directly sample and test each batch of blendstock, and treat the blendstock as the produced batch for blendstock that is blended into previously certified gasoline (PCG).  We are proposing to add §80.1347(a)(6) to reflect this alternative.  This practice is already allowed under the Tier 2 sulfur program (at §80.340(a)(2)).  Refiners and importers are currently required to test the PCG for benzene before addition of blendstock, test the combined blend of PCG and blendstock for benzene, and calculate the properties of the blendstock by treating the PCG as a negative volume batch and treating the blended product as a positive batch.  Due to variability in the benzene test method, the PCG approach can sometimes result in calculated blendstock benzene concentrations that are negative, which is physically impossible.  We are proposing to amend the regulations at §80.1235(a)(6) (and add §80.1347(a)(6), as mentioned) to allow refiners and importers that blend blendstock into PCG an alternative to directly test the blendstock for benzene.  We expect that this would ensure a positive benzene test result.  Also, today's proposal would clarify that regardless of the approach used, a negative sulfur or benzene result cannot be reported; rather, any negative result must be rounded to zero.  Similarly, no negative annual average result can be reported.  We are also proposing to amend the regulations at §80.1235(a)(5) to clarify that refiners and importers may use either approach for blendstocks that are blended into either conventional gasoline or reformulated gasoline.
Lastly, we are proposing to allow importers who import gasoline into the United States by truck to use the sampling and testing requirements in subpart E for truck importers as an alternative to the sampling and testing requirements in subpart L.  EPA provided these alternative requirements in subpart E to eliminate the need to test every truckload of imported conventional gasoline for all complex model parameters, including benzene.  Since Subpart L also requires importers to test every truckload of imported gasoline for benzene, EPA believes it is appropriate to allow truck importers of gasoline to use the sampling and testing requirements in subpart E as an alternative.  Today's rule proposes to amend the regulations to provide this alternative by adding a new §80.1349.
        Amendments Related to Designation of an Alternative Lab
Refiners have indicated to EPA that significant problems are created when a facility's designated lab is nonoperational and testing cannot be performed at the lab during that time period.  We are thus proposing (at §80.65(f)(5)) that a facility have the ability to designate a back-up or alternative lab for testing during such times.  In no case could this alternative lab be used to select the best test result, rather it could only be used on those occasions where operational necessity causes a need for it (e.g., the normal lab is closed, the apparatus for certain test methods are down, or independent lab personnel are not available).
        Amendments Related to De Minimis Reporting Changes
We are proposing for the correction of batch volume reports to allow for de minimis changes in reporting compliance that would not require a complete resubmission of compliance reports when a minor discrepancy of a few barrels is uncovered.  This allowance for the correction of batch volume reports would apply to reporting for: RFG, anti-dumping, gasoline and diesel sulfur, MSAT2 and the RFS renewable volume obligation (RVO) (for RFS, this would only apply to the volume of fuels produced or exported that result in a RVO for obligated parties).  We are proposing a new section 80.10 to define de minimis, for the purpose of this allowance, as no more than 500 gallons or by no more than 1 percent of the true batch volume in gallons, whichever value is less.  We request comment on whether or not a different amount would be more appropriate.
        Amendments Related to RFS2 Annual Report Date
Currently, the RFS2 final reporting date (last day of February) coincides with the RFG and Anti-dumping compliance deadline, which creates a staffing problem for regulated entities because the regulatory requirements are often handled by the same personnel.  It was reported to EPA that this also creates an issue when small discrepancies in gasoline production or import volumes are realized, and can potentially trigger an increased RFS RVO and an ensuing scramble to obtain the necessary Renewable Identification Numbers (RINs) in real time.  Delaying the RFS reporting date until after volumetric auditing would address this situation and would have no impact on emissions, air quality or compliance with the standard.  As such, we are proposing to change the RFS2 reporting date in §80.1451 to March 31.  EPA is also seeking comment on whether the ability to transfer RINs in EMTS for satisfying RVOs under the previous compliance year should be extended from the last day of February to March 31 as well.
        Acceptance of Alternate Test Data Under the Gasoline Deposit Control Program
The "Top Tier" deposit control gasoline standards developed by four major automakers are based on the premise that a more robust level of the control of vehicle engine and fuel systems beyond that provided by the EPA deposit control requirements is desirable.  Several major gasoline marketers have adopted Top Tier for their gasoline.  It is widely accepted that conformance with the Top Tier intake valve deposit (IVD) and fuel injector deposit (FID) control testing requirements is more challenging than complying with the EPA IVD and FID testing requirements.  Yet additive packages must still be certified to EPA's less stringent standards on older test procedures.  We believe that EPA could accept IVD/FID test data that complies with the Top Tier requirements in place of IVD/FID data that complies with the current EPA testing requirements without jeopardizing the emissions benefits from EPA's deposit control program.  We are proposing that test data that complies with the Top Tier IVD performance standards at section 1.3.1 could be used to satisfy EPA's IVD control requirements.  We are also proposing that test data that complies with the Top Tier FID performance testing standards at section 1.3.3 could be used to satisfy EPA's FID control requirements.  We believe that this allowance would provide significant saving to industry from reduced deposit control testing while maintaining the emissions benefits of EPA's gasoline deposit control program.  These changes are being proposed in the regulations at §§80.161(b), 80.163(a)(1)(iii), 80.164(a), 80.165, 80.167(a), 80.176, and 80.177.
Broader Regulatory Streamlining Through Program Restructuring
The current set of fuel regulations is the result of programs that have been established over the years to reduce emissions from mobile sources.  These programs include gasoline volatility (RVP), reformulated gasoline and anti-dumping, sulfur control (which the Tier 3 program proposed today would revise), mobile source air toxics (MSAT1), benzene control (MSAT2), and the renewable fuel standards (RFS).  Most of these regulations have been amended numerous times.
The RFG and anti-dumping regulations in particular contain some of the more burdensome requirements on sampling, testing, and reporting.  They also have some of the more stringent restrictions on gasoline use (e.g., restricting where fuel produced can be sold, what it may be commingled with, etc.).  EPA used the RFG and anti-dumping rules as the foundation for many aspects of subsequently developed fuel regulatory programs.  However, the subsequent rules, considered as a whole, have supplanted most of the RFG and anti-dumping standards.  For this reason, we are proposing to streamline the regulations in several places as described above.  Initial discussions with fuel industry representatives have indicated that a comprehensive review of the complete set of fuel regulations contained in Parts 79 and 80 ("Registration of Fuels and Fuel Additives" and "Regulation of Fuels and Fuel Additives," respectively) of the Code of Federal Regulations could lead to further streamlining of the regulations beyond the streamlining provisions proposed today.
EPA expects that streamlining would result in more efficient and less costly compliance determinations for affected parties while maintaining the environmental benefits of the programs. Since such changes could require not just the removal or streamlining of existing provisions but also the replacement of several provisions with new, less onerous ones, we are not proposing such changes today.  However, EPA requests comments on potential areas in the fuel regulations that may benefit from such a more comprehensive streamlining effort.  For example, it may be possible for the RFG VOC standard to be met if a sufficiently stringent RVP level is attained.  Under this scenario, sampling and testing requirements at the refinery would be reduced.  Another potential scenario could involve consolidation of some RFG and anti-dumping rules; for example, a single set of rules governing the treatment of downstream ethanol blending and in-use surveys could provide greater efficiency and flexibility regarding fuel distribution.
Subpart I Technical Amendments
Table VI-3 40 CFR Part 80 Subpart I (Diesel Fuel) Technical Amendments
Section
Description
80.572(a)
Amended to remove the requirement for 15 ppm highway diesel fuel pump labels beginning November 30, 2014, and to amend the title to reflect that the section includes labeling requirements for dispensers of motor vehicle diesel fuel.
80.584(b)(3)(i)
Amended to correct typographical error ("notc" to "not").
We are proposing to remove the requirement for diesel fuel pump labels for 15 ppm highway diesel fuel.  Beginning December 1, 2010, all highway diesel fuel was required to be 15 ppm or less; thus, highway diesel fuel labels are no longer needed to distinguish it from 500 ppm highway diesel fuel.  However, we do recognize that it may confuse consumers who are accustomed to seeing the highway diesel fuel pump labels if those labels were to disappear, so we are also requesting comment on the removal of this labeling requirement.  Note that if highway diesel fuel pump labels are no longer required by the regulations, retail and wholesale purchaser-consumer facilities would be free to continue labeling to eliminate confusion if they so choose.
Performance-Based Measurement Systems (PBMS)
Table VI-4 PBMS-Related Technical Amendments
Section
Description
80.46
Amended to allow for performance-based approaches for measuring gasoline parameters.
80.47
Added to extend the performance-based approach to other parameters besides diesel sulfur.
80.101(i)(1)(i)(A), (i)(3)(i)(C), (i)(3)(ii)(C)
Amended to allow for performance-based approaches for measuring gasoline parameters.
80.330(c)(1), (d)(1), (d)(2)
Amended to allow for performance-based approaches for sampling and testing.
80.370(a)(7)(iv)
Amended to require identification of the test method used to measure the sulfur content of a batch.
80.585(a) and (d)(4)
Amended to state the process for approval of test methods prior to and after adoption of PBMS for all fuel programs.
80.1348
Amended to state the sample retention requirements prior to and after adoption of PBMS for all fuel programs.
80.1354(b)(2)
Amended to require identification of the test method used to measure the benzene concentration of a batch.
Consistent with EPA's performance-based measurement system (PBMS) initiative (as discussed below), today we are proposing a PBMS for those chemical and physical properties of motor vehicle fuels regulated by EPA's motor vehicle fuel programs.  Specifically, these are gasoline properties at §80.46, gasoline sulfur at §§80.195 and 80.1603, and diesel fuel properties at §80.2(z).  This PBMS sets forth procedures and criteria by which laboratories making measurements to demonstrate compliance with fuels regulations may qualify alternative analytical test methods to those required in the regulations.  It also sets minimum statistical quality control (SQC) requirements, following standard industry practices, by which laboratories must maintain and document the precision and accuracy of analytical methods used in the context of these programs.  EPA envisions that the proposed PBMS would provide additional flexibility to the regulated industry in choosing test methods and foster innovation and improvement in the precision and accuracy of the measurement of motor fuel properties while not making any reductions in the emission benefits that result from motor fuel programs.  It should also provide cost savings to the regulated industry by providing rapid access to newly-developed test methods with speed and ease of analysis.  Some of these newer methods use smaller quantities of consumables and less-expensive instrumentation that are easier to automate, thus reducing both operating costs and environmental impact.
Background
Refiners, importers and oxygenate blenders producing RFG, conventional gasoline and diesel fuel are required to test these fuels to determine the levels of various specified parameters.  A designated test method is associated with each parameter to be tested (except for sulfur concentration in ultra-low sulfur diesel fuel, which must meet performance-based requirements) in 40 CFR part 80.  Table VI-5 lists the parameters/fuels and their corresponding designated test methods that we are proposing to update.
Table VI-5 Designated Analytical Test Methods for Gasoline and Diesel Fuel
Fuel Parameter
Designated Analytical Method
Sulfur in gasoline
ASTM D 2622-10
Sulfur in butane
ASTM D 6667-10
500 ppm Sulfur Diesel Fuel
ASTM D 2622-10
Olefins in gasoline
ASTM 1319-10
Reid vapor pressure (RVP) in gasoline
ASTM D 5191-10b, with the following correlation equation:
RVP psi = (0.956 * X) - 0.347
RVP kPa = (0.956 * X) - 2.39
where:
X = total measured vapor pressure in psi or kPa.
Distillation in gasoline
ASTM D86-11a
Benzene in gasoline
ASTM D 3606-10, except that instrument parameters shall be adjusted to ensure complete resolution of benzene, ethanol, and methanol peaks.
Aromatics in gasoline
ASTM D 5769-10, except that sample chilling requirements in section 8 of this standard are optional.
Oxygen and oxygenate content in gasoline
ASTM D 5599-00(2010)
Aromatics in diesel fuel
ASTM D1319-10
In addition to the designated analytic methods for the parameters mentioned above, EPA has specified alternative test methods for some parameters.  These alternative test methods may be used in lieu of the corresponding designated test methods, provided that all test results are correlated to the appropriate designated test methods.  Alternative test methods have not been established for all regulated motor vehicle fuel parameters, however.  Specifically, alternative test methods have been established for measuring the gasoline properties of aromatic content, oxygenate content, olefin content, and sulfur content as well as sulfur in butane.  Currently, if a regulated party wishes to use an alternative test method that is not already approved, it must petition the Agency, and EPA must approve the use of this alternative method through a rulemaking process that on average, may take more than a year to complete.
Approving new methods through rulemaking has been identified as a barrier to the use of innovative analytical test methods.  In order to address these concerns and similar ones in other media areas, the Agency's Environmental Monitoring Management Council established a workgroup of scientists representing EPA's Headquarters and Regional offices to consider establishing a performance-based approach to specifying analytical testing requirements.  On the recommendations of the workgroup, the Agency decided to incorporate the PBMS approach into its programs, to the extent feasible.
EPA's practice, in recent rulemaking activities, of aligning its prescribed methods with those published by Voluntary Consensus-based Standards Bodies (VCSBs) is almost consistent with the PBMS policy and with the National Technology Transfer and Advancement Act (NTTAA).  For example, in the nonroad diesel rulemaking, which controlled the sulfur content of diesel fuel, EPA required only that laboratories demonstrate their test methods' ability to meet a set performance criteria rather than prescribing that a single specific method be used.  Today's proposal extends the diesel sulfur qualification approach to the chemical/physical properties measured in other motor vehicle fuel programs, with modifications appropriate to accommodate the differences among the fuel parameters.
Overview of Proposed Program Requirements
In a June 29, 2004 rulemaking, EPA specified a performance-based approach to measuring diesel sulfur at 15 ppm and 500 ppm and removed the previous requirement of particular designated and alternative methods for 15 ppm diesel sulfur.  We decided, in that rulemaking, to offer users two approaches to selecting test methods for diesel sulfur at the 500 ppm level.  The first of these was to use either the designated test method or specific alternative test methods.  The second option was to meet performance based requirements similar to those adopted for 15 ppm diesel sulfur.  We are proposing today to extend the performance-based approach to method selection and qualification to other parameters besides diesel sulfur, with modifications appropriate to accommodate the differences among the fuel parameters.
Specifically, we are proposing requirements that laboratories would be required to demonstrate the precision and accuracy of chosen fuel parameter measurement methods.  Once implemented, this proposal would: (1) require individual laboratories to demonstrate adequate measurement quality, (2) allow laboratories to choose methods that meet their own needs, provided they can meet prescribed criteria rather than specific methods, and (3) require all laboratories making regulatory measurements to establish and maintain a statistical quality control program.  EPA intends that the measurement system resulting from this proposal would make no compromises on precision or accuracy relative to the system that exists under current regulations.  We intend to incorporate the standards and practices of Voluntary Consensus Standards Body (VCSB) organizations wherever feasible.
Today's PBMS approach applies to the qualification of analytical test instrumentation and methods used to measure various characteristics of individual fuel samples.  It does not apply to sampling methods or in-line blending methods.  While in-line blending certainly includes the use of analytical measurements, it is broader in scope than this proposal.  Including in-line blending methodologies in this proposed rulemaking would raise issues that could not be adequately addressed in the context of this proposed rulemaking.  Furthermore, in-line blending already has a certification process, as specified in regulations at §80.65(f), that sets forth qualification criteria that take into account the unique combinations of sampling, control, and analysis that are involved with in-line blending.  However, we seek comment on potentially expanding our PBMS to include sampling or in-line blending methods.
      How Can We Establish the Accuracy of the Measurement System (All Qualified Methods/Installations) For Each Parameter?
We are proposing to group the gasoline and diesel fuel parameters that must be measured (e.g., aromatics, sulfur, etc.), into two categories.  These categories depend on whether it is feasible to construct and use gravimetric standards for defining the parameter and thus determining the accuracy of a measurement method.  For some parameters it is difficult or perhaps impossible to make gravimetric standards.  This is particularly true where the parameter is actually a class of chemical compounds (themselves containing multiple chemical compounds) that may have a very large number of members (e.g., aromatics in gasoline).  Use of gravimetric standards for establishing accuracy may also be hindered if many of the potential measurement methods are sensitive to the chemical composition of the material that the analyte is added (often called the "matrix") and are thus prone to being "confused" into giving inaccurate answers.  Where these two problems are not present, the use of gravimetric standards is the ideal way to establish the accuracy of the analytical test method.  We will describe these as "absolute" parameters.  The accuracy qualification test for a method measuring such parameters should center upon its being able to get the "right" answer for one or more gravimetric standards.
To establish the accuracy of methods measuring each parameter where gravimetric standards hindered, we are proposing to retain an EPA-prescribed reference method or "designated method" that would, in effect, define the parameter as "parameter X is, for federal regulatory purposes, whatever method Z measures."  Parameters that require such treatment will be described as "method-defined" parameters.  Establishing the accuracy of a method intended to measure such a parameter would be accomplished by relating its measurements on a particular set of test fuels to measurements made on the same fuels by a laboratory operating the designated method.  This approach is often referred to as correlating the new method with the designated method.  In other words, measurements from the new method (the "candidate" for qualification) would be used to predict the measurements that the designated method would get on the same fuels (with, perhaps, some offset or adjustment equation applied) and then these predictions would be compared with the actual measurements made from those fuels by the designated method.  If the predictions are consistently close to the designated method measurements and evenly distributed above and below these reference values, then the laboratory and the method it proposes to use would have a good case for qualification with regard to accuracy.  Such a correlative approach to qualification is dependent for its workability upon the test fuels used to establish the correlation.  Such fuels must be sufficiently varied along all important dimensions so that day-to-day production laboratory operations are very unlikely to turn up some unusual fuels (or a new class of fuels produced, say, by some new refining process) for which the correlation equation derived earlier is not accurate and where the predictions of the designated method's results are quite erratic and inaccurate.
In addition to the dependence of the method-defined approach upon the choice of fuels for establishing the correlation to the designated method, this approach also greatly elevates the importance of the designated method that is used.  An increasingly obsolete designated method might need to be changed for practical reasons, but adoption of a new designated method could bring about a de facto change in the standard for the parameter in the absence of a prescribed correction equation designed to align the new designated method with the old.  While the gravimetric approach to measurement has its own problems, it is free of the difficulties associated with any particular method.
Our classification of parameters into the absolute or method-defined categories is not entirely straightforward.  Of the parameters subject to this proposal, only those with sulfur as the analyte fall into the absolute category.  Sulfur is a single element rather than a compound (or, worse, a class of compounds with numerous members) and thus lends itself to the construction of gravimetric standards.  The methods that are currently used to measure sulfur in gasoline and diesel fuel have been subject to intensive recent development work and are largely free of matrix effects.  Sulfur in butane is even more amenable to the absolute approach, since butane is a single compound rather than a constantly varying mixture of many compounds.  We also note, as mentioned before, that the diesel sulfur rule used the absolute approach.  For these reasons we are proposing to treat gasoline sulfur and sulfur in butane as absolute parameters.
Beyond these two sulfur parameters, classification becomes more difficult.  Where the analyte is a class of compounds, like aromatics, the construction of a gravimetric standard would have to be done by use of an agreed-upon conventional recipe that includes some group of the compounds in the class in proportions that approximate to what is found in the actual fuels that a method will measure.  If the class has relatively few compounds and they are all available in reasonably pure form, then they could all be included in the standard, leaving only the issues of their respective concentrations (likely to vary among real fuels) and the question of "matrix effects" as discussed above.  Where the class of compounds has many members and not all could be included in an artificially constructed standard, we are left with the question of which ones can be omitted on grounds that they are likely to occur only in very small concentrations and/or are not particularly important in emission formation.  The result of these exclusions, for certain parameters, would likely be a directional bias toward underestimating the prevalence of the target class of compounds.  The likely size of the bias will vary among parameters and among fuels on which measurements are made.  Use of a complex recipe for such standards, where possible, may minimize the bias, but may add to the costs and difficulty of formulating a standard representative of all fuels.
The distillation parameters (T50 and T90) seem to be largely resistant to a gravimetric approach that relies on pure compounds instead of the smooth curve that results from simple distillation of complex mixtures like gasoline and diesel fuel. Such gravimetric standards, incorporating only a very limited number of compounds out of practical necessity, would be likely to yield a kind of stair-step curve.
Given these logical and practical difficulties with using a gravimetric approach to qualifying methods for parameters other than sulfur, EPA is today proposing that the method-defined or correlative approach be used for all parameters other than sulfur.  We are especially interested in receiving comment on our categorization of fuel parameters as either absolute or method defined.
How Would Analytic Methods be Evaluated for Qualification?
        General Provisions: To Which Methods and Which Parties do the Proposed Requirements Apply?
As discussed above, EPA believes that the interests of measurement quality are best served by evaluating most method installations for qualification at the level of individual laboratories instead of individual instruments.  This approach was used in regulating diesel sulfur.  We are proposing to require laboratories to qualify all methods that will be used to make measurements for regulatory purposes.  EPA does not believe that a relatively simple qualification test will ensure continued measurement quality, but rather that this will greatly reduce the likelihood of a laboratory undertaking important measurements without some assurance that the instrument is in working order, that at least one operator in the laboratory understands the method for its use, and that it can be made to perform to meet acceptable criteria.  We seek comment on requiring laboratories to qualify all methods used to take measurements for regulatory purposes.
        How Would Laboratories Demonstrate the Precision and Accuracy of Methods for Measuring "Absolute" Parameters and Thus Qualify the Methods for Use?
We are proposing to require a separate qualification for test methods used to measure gasoline sulfur.  As mentioned previously, the Agency has successfully implemented performance based requirements for sulfur in diesel fuel.  The test methods typically used for gasoline sulfur (one of the two parameters we are proposing to consider absolute, as discussed above) are also frequently used for diesel sulfur and the ASTM test method designations for both are the same.  However, examination of test method descriptions points toward substantial differences in how the test methods are used in the different matrices.  One example is a requirement for recalibration when matrices shift.  While we considered the possibility of allowing the diesel sulfur qualifications to be used also for gasoline sulfur, we believe the differences between a diesel fuel matrix and gasoline fuel matrix may be too great to permit such a sweeping exemption from qualification requirements.  The process of reworking the test methods to measure gasoline sulfur will, in many cases, generate most of the data needed for qualification, and thus will not represent a major additional effort.  So, despite the fact that ASTM test methods are the same for gasoline and diesel, we are proposing to require separate qualification for test methods used in measuring gasoline sulfur.
Operational Description.   We are proposing to require applications for qualification to include a complete operational description of the test method in question.  A VCSB publication would satisfy this requirement for methods published by such organizations as ASTM.  The description must include the scope of the test method, a summary, discussion of any interferences that are expected, apparatus needed, reagents, sampling and specimen preparation, calibration, test method procedure, calculations, and any test method-specific quality control.
Precision Qualification.   We are proposing requirements for precision qualification that are similar to requirements set forth in the nonroad diesel sulfur rule.  That rule imposed a maximum value for the standard deviation of a series of at least 20 measurements over at least 20 days on a single fuel under site precision conditions.  Specifically, the diesel rule used 1.5 times the repeatability standard deviation (ASTM "r"/2.77) of what was the least precise of the then-allowed methods.  The factor of 1.5, expands the allowable variability from that of back-to-back tests (as in ASTM's definition of repeatability) to account for the sources of greater variability that find their way into a longer series of tests on the same material.  In the qualification process for ultra-low sulfur diesel testing, the factor of 1.5 proved to be neither so tight that most laboratories were unable to meet it, nor so loose as to not be challenging at all.  Thus we consider it to be reasonable on its face, as well as having proven to be workable in practice, and we have therefore retained it in this proposal.  We request comments on the selection of a test method's repeatability to use as the basis of the qualification.
Gasoline Sulfur Criterion.  We are proposing to use the ASTM repeatability standard deviation factor as discussed above from ASTM D7039-07 to set the precision criteria for gasoline sulfur.  We note that there is a designated test method and four alternative test methods for gasoline sulfur.  The larger repeatability among the test methods currently allowed for sulfur in gasoline is for ASTM D6920-07.  This was obtained only when the substantially more variable of the two instrument models included in a small inter-laboratory study was included.  Since the most variable instrument model had a repeatability of nearly twice that of the other test methods and over four times that of the other instrument model for the same method, we believe that ASTM D6920-07 should be represented, for this purpose, by the instrument model yielding the better performance of the two.  Given that decision, ASTM D7039-07 is left with the largest repeatability of these test methods.  And we are proposing to use its repeatability (1.76 ppm at 10 ppm) to set the precision criterion for this parameter.  Thus the maximum allowable standard deviation of the twenty test results on a 10 ppm gasoline would be 0.95 ppm.  Since we do not propose to prescribe the parameter level for the fuel used for these precision tests, this maximum limit will vary depending upon the repeatability number that the ASTM D7039-07 test method's repeatability formula yields, given the parameter value of the test fuel chosen.  If a laboratory selected a 5 ppm fuel to test instead of a 10 ppm fuel, the maximum limit for the standard deviation would be 0.67 ppm.
Sulfur in Butane Precision Criteria.  There are three test methods currently allowed for measuring the sulfur content of butane for blending into gasoline.  A new designated test method was adopted for this parameter (ASTM D6667-10) because the previous primary test method, D3246-11, had become somewhat obsolete.  Given that D3246-11 is no longer widely available, though still an allowed alternative test method, and that the range of D4468-85 (reapproved 2006) extends only to 20 ppm, we are proposing a precision criterion based on the repeatability of D6667-10.  This test method's repeatability at the 10 ppm level is 1.15 ppm, so the calculations used above with gasoline sulfur yield an upper limit for the standard deviation of the 20 tests for sulfur in butane of 0.62 ppm.
Temporal Distribution of Precision Tests.   With regard to spacing of the 20 precision tests, we are proposing 7 or fewer tests per week and 2 or fewer tests per day. We believe this would prevent weekend testing while also precluding practices such as conducting one test on the first day and 19 tests on the 20[th] day.  We believe that adequate spacing of testing is necessary if we are to have a meaningful standard for the longer-term stability of a particular test method in a particular laboratory installation.   We are also taking comments on the following two options: (1) a requirement that 23 or more hours must elapse between tests (this option requires either testing on weekends or an extension of the 20 days); and (2) tests arranged into no fewer than five batches of five or fewer tests each, with only one such batch allowed per day.
Accuracy Qualification.  We are proposing accuracy criteria for absolute fuel parameters that are similar to the criteria for sulfur in diesel fuel.  Applicants for qualification would be required to select two commercially available gravimetric standard reference materials and then to show that their laboratory and method are capable of getting an average of ten consecutive results that are very close to the Accepted Reference Value or ARV for each.  How close to the ARV these averages must be is the stringency part, and we propose to use 0.75 times the precision criterion described above, which is the same value as the diesel rules.  In the case of gasoline sulfur, for a gravimetric standard with ARV = 10 ppm, this would be 0.75 times 0.95 ppm or 0.71 ppm.  The corresponding numbers for sulfur in butane at the 10 ppm level would be 0.75 times 1.15 or 0.47 ppm.  We are proposing that for other parameter that might come to fall into the absolute category, the precision and accuracy criteria would be determined as a function of the ASTM repeatability of one of the methods (selected by EPA) available for measuring that parameter.
        How Would Laboratories Demonstrate The Precision and Accuracy of Methods for Measuring "Method-Defined" Parameters and Qualify the Methods for Use?
Operational Description.  For method-defined parameters we are proposing the same operational description as that for absolute parameters.  The operational description of a proposed test method must be very complete.  We consider publication of a test method by a VCSB organization such as ASTM to meet this criterion.  For non-VCSB test methods this description must meet very high standards for completeness and clarity.  Since non-VCSB test methods have not been fully vetted by a VCSB, a non-VCSB test method would require additional information.  In particular, the underlying scientific measurement principles must be thoroughly explained and the apparatus described well enough that a trained outsider could successfully implement the non-VCSB test method and replicate the applicant's results.
Precision Qualification Specifics.  We are proposing the same precision qualification criteria as absolute parameters. For those method-defined parameters with alternative test methods that have been identified by regulations, preference will be given to the least precise of the allowed test methods.  For reference installations we propose the additional requirements that the instrument must be shown to be in statistical control, as provided for in ASTM D6299-10[e1] (and the SQC procedures to be discussed below); and that the applicant must submit control charts showing a record of in-control operation for at least five months.  While these requirements would likely result in a delay between instrument setup and the ability to qualify it as a reference installation, we believe that the delay is necessary to demonstrate the stability of these critically important installations.  Considering the number of long-established installations of these designated test methods, EPA expects no lack of laboratories capable of meeting these standards and able to provide this service commercially to any party interested in qualifying a new installation of an alternative test method for a method-defined parameter.   Table VI-6 sets out our proposed precision criteria for the various method-defined fuel parameters with no alternative test method.
Olefins in Gasoline Criterion.  The designated method for this parameter, ASTM D 1319-10, is also the less precise of the two methods currently allowed.  As such, its repeatability statistics are proposed as the basis for precision qualification.  Thus for a test fuel with olefins at, say, 9 volume percent, the repeatability is 0.972, and the underlying standard deviation is  0.972/2.77=0.351, and the precision criterion is 1.5 times that, or 0.53 volume percent.  A laboratory's standard deviation for the 20 tests could not exceed that value and still qualify for precision.
Aromatics in Gasoline Criterion.  We are proposing to use the repeatability standard deviation for D1319-10 to set the precision criteria for aromatics in gasoline.  (e.g., 1.3 volume percent for a fuel with 32 volume percent aromatics). The cut off point for the 20-test standard deviation using the test fuel would then be 0.70 volume percent.  We note that D5769-10 is the current designated test method but that D1319-10 is still widely used.  We also note that while not as precise as D5769-10, D1319-10 is the designated method for olefins, and has precision sufficiently close to that of the more modern designated method to make it still viable.
Oxygen and Oxygenates in Gasoline Criterion.  The two test methods allowed for oxygen are very close together in precision, at least for total oxygen content.  The designated method, D5599-00(2010) is slightly less precise, leading us to propose that its repeatability be used to determine the criterion.  So for a test gasoline with 3 mass percent total oxygen, the repeatability would be 0.083 mass percent and the criterion for precision in this example comes out to 0.045 mass percent.
Table VI-6 Method-Defined Precision Criterion for Fuel Parameters with no Alternatives to the Designated Test Method
Fuel Parameter
Example of fuel parameter level for demonstrating precision
Proposed Precision Criterion
RVP in gasoline
RVP sample of gasoline equals 6.8 psi
0.11 psi
Distillation in gasoline
Gasoline sample with initial boiling point (IBP) of 20 °C and 90 percent evaporated (E90) temperature of 110 °C
IBP = 1.54 °C
E10 = 0.72 °C
E50 = 0.40 °C
E90 = 0.97 °C
FBP = 1.80 °C
Benzene in gasoline
Gasoline sample containing 1 volume percent benzene
0.02 volume percent benzene
Aromatics in diesel fuel
Diesel sample containing 35 volume percent aromatics
0.70 volume percent
Accuracy Qualification.  Test methods used to measure method-defined parameters can be grouped into three types: reference installations of designated methods intended for use in qualifying alternative methods; designated method installations intended for ordinary production measurements; and non-designated methods.  Since these reference installations will be used to evaluate the accuracy of other test methods and to evaluate whether the need for the establishment of a correlation equation.  We are proposing that such reference instruments must be shown to be near the middle of the distribution of the industry monthly inter-laboratory crosscheck program for at least five months prior to application.  We are proposing that laboratories would specifically compute the difference between either the instrument's average measurement of the fuel closest to the applicable standards or to the average value for the fuel type in the complex model and the robust mean for that fuel obtained by all of the non-outlier labs in the program.  We are proposing that the differences would then be standardized by expressing it in robust standard deviation units.  This standardized inter-laboratory cross check (ILCC) differences would be put into a moving average with a span of, for example, five months.  We are also proposing to set the standard such that the instrument's moving average would be within the central 50 percent of the distribution of participating designated method labs.  Because a robust standard deviation is used by the ILCC program, this percentage will have to be approximate.  Such lab-specific qualification would be outside of the normal qualification of a lab for making regulatory measurements for certifying fuel and would pertain only to use of the instrument in certifying other methods.  EPA requests comment on the nature and stringency of this proposed requirement.  Specifically, we request comment as to whether this is a reasonable requirement that is likely to be met by instruments in the best qualified laboratories.  Could the "middle 50 percent" requirement be further tightened without severely restricting the supply of potential reference installations?  Are there computationally simpler ways to accomplish the general purpose of this requirement?
        Role of Voluntary Consensus Bodies in Qualifying Alternative Analytical Test Methods
In February 1996, Section 12(d) of Public Law 104-113, Congress passed the National Technology Transfer and Advancement Act of 1995" (NTTAA), in order to establish the policies of the existing OMB Circular A-119 in law.  The purposes of Section 12(d) of Public Law 104-113 are: (1) To direct "federal agencies to focus upon increasing their use of [voluntary consensus] standards whenever possible," thus reducing federal procurement and operating costs; and (2) to authorize the National Institute of Standards and Technology (NIST) as the "federal coordinator for government entities responsible for the development of technical standards and conformity assessment activities," thus eliminating "unnecessary duplication of conformity assessment activities."  Section 21(d) of Public Law 104-113 also gives agencies the discretion to use other standards in lieu of voluntary consensus standards where use of the latter would be "inconsistent with applicable law or otherwise impractical."  However, in such cases, the head of an agency or department must send to OMB, through NIST, "an explanation of the reasons for using such standards."
The final revision of Circular A-119 defines Voluntary Consensus Standards as "standards developed or adopted by voluntary consensus bodies, both domestic and international", and defines VCSB as "domestic or international organizations which plan, develop, establish, or coordinate voluntary consensus standards using agreed-upon procedures and which possess the attributes of openness, balance of interest, due process, an appeals process, and consensus."  Finally, Circular A-119 indicates that consensus means "general agreement, but not necessarily unanimity, and includes a process for attempting to resolve objections by interested parties, as long as all comments have been fairly considered, each objector is advised of the disposition of his or her objection(s) and the reasons why, and the consensus body members are given an opportunity to change their votes after reviewing the comments."
The Agency believes that VCSBs can play a valuable role in developing statistical tools for analytical test methodology description and evaluation, developing and describing new analytical test methodologies and organizing test programs to evaluate methodologies and assist laboratories to maintain quality measurement systems.
EPA has frequently selected VCSB-developed methods as its designated methods for fuels programs.  However, it has only adopted a particular version of each such method by incorporating it by reference in the Federal Register.  In each case the Agency was endorsing and adopting test methods that were completely known and available for examination, rather than the unknown result of some future VCSB action.  To simply say that any method approved by a VCSB is acceptable for all purposes, including compliance demonstrations would seem to invite such difficulties as:  (1) multiple methods for a parameter, developed by different VCSB's and not correlated adequately with each other, or  (2) methods that change over time (by publication of new versions, for example) in such a way that the definition of what is being measured changes and no longer corresponds to what was used in setting compliance to the environmental standard(s).
        Use of Reference Materials in Qualifying and Maintaining Alternative Analytical Techniques
Depending on the qualification process chosen by the Agency, discussed in more detail below, the protocol proposed here for the qualification and maintenance of alternative test methods stops short of automatic acceptance of VCSB decisions and methods, but goes as far in that direction as we believe is consistent with the Agency's mission of ensuring compliance with motor vehicle fuel programs.  It gives some preference to VCSB-approved methods because of our greater confidence that such methods have been positively evaluated by a broad user community rather than by a narrower array of users.  We are proposing today to also make substantial use of VCSB-developed statistical protocols for comparing methods and for use by particular laboratories in keeping analytic methods under adequate statistical quality control.
We consider Reference materials to be samples of the type of material to be tested (gasoline or diesel fuel in this case) that are known or thought to have a particular concentration of the substance to be measured.  Laboratories may use these materials to calibrate and evaluate the performance of measurement systems.  EPA is proposing the following three types of reference materials that would be used in establishing and maintaining the accuracy of both designated and alternative analytical test methods: (1) gravimetric standards, (2) consensus-named fuels (gasoline or diesel fuel), and (3) locally-named standards.
Additionally, some combinations of parameters and test methods limit the availability of some kinds of reference materials.  This complicates the task of developing a methodology for qualifying alternative test methods.  EPA recognizes the technical complexity and the likelihood that new analytical testing methods may emerge.  Therefore, the Agency is also proposing to offer substantial flexibility in the choice of standard reference materials and the manner of their use, so long as they ensure accuracy and preserve the integrity of applicable fuel standards.
Gravimetric Reference Standards.  Gravimetric standards are test materials made by adding a carefully measured quantity of the analyte of interest to a measured quantity of another substance known not to contain any of the analyte.  The result is a solution with a very accurately known concentration of the analyte.  The accuracy of gravimetric standard reference materials can be closely controlled and is not dependent on an analytical test method. They do present certain practical problems in use.  First, gravimetric reference materials cannot be made for all of the parameters under the RFG, CG and diesel fuel programs (e.g., distillation points and olefins).  Second, there are "matrix effects."  As earlier explained, matrix effects are where components in real-world gasoline or diesel fuel other than the analyte of interest confuse the instrument and cause it to measure the analyte differently than it would when measuring the same concentration of the analyte in a gravimetric standard built in a matrix where the instrument is not sensitive.  Matrix effects are problematic for certain analytical methods, whose underlying scientific operating principles make the analytical method unable to utilize gravimetric standards for calibration when other types of materials (gasoline or diesel fuel) will have to be measured accurately.  The approach taken in this proposal, where the gravimetric standard reference materials would be used in establishing the accuracy of a reference implementation of the designated method, is an approach that should minimize matrix effect problems.  This is because the designated methods were selected, among other criteria, for their relative freedom from matrix effects.  Thus, EPA believes that such materials, offer the best tools for establishing the accuracy of analytical test methods.  When feasible, EPA believes that gravimetric reference standard materials should form the basis for establishing accuracy through correlation with designated analytical test methods calibrated with gravimetric standards.
Consensus-named Fuels.  These are homogeneous quantities of fuel that have been analyzed by a number of different laboratories (by sending around small samples).  The average concentration of some parameter of interest across all of the different laboratories is then used as the "consensus name" for that material.
There are certain parameters that the Agency does not believe that gravimetric standard reference materials can be prepared.  Aromatics are a class of numerous compounds that are produced by refinery processes in a mixture that is most likely impossible to duplicate in the laboratory with any consistency for all fuel because not all refiners have the same configuration.  For such parameters, it is therefore necessary to use consensus-named gasolines to control accuracy because they are the only reliable type of standard reference material that is available.  The use of consensus-named gasolines may minimize matrix-related effects where they are used to establish the accuracy of different designated method implementations, though they may be less useful in evaluating alternative methods that have been adapted to measure a certain fuel matrix, but not sensitive enough to measure all fuel matrices the test method may encounter in use, otherwise known as "adaptive learning" technologies.  The nominal concentrations in consensus-named gasolines can only be as accurate as the designated analytical test method used in the VCSB round robin study that named them.  Consensus-named gasolines will also be costly and time-consuming to produce and will need to be periodically replaced (i.e., when the supply is exhausted or the shelf life expires) through either a new round robin study or some approach using overlapped testing of the old standard reference material with a new batch (which will not, of course, have exactly the same concentration of analytes).
Locally Named Reference Materials.  These materials are also sometimes referred to as quality control samples (e.g., octane testing reference fuel).  These are gasoline or diesel fuels that usually come from the regular production of the facility.  These reference materials are used in laboratory quality control efforts and have been analyzed using the designated method (either by the facility's lab or by a referee lab) to obtain an estimate of their concentration.  The fuels are then stored carefully by the lab to slow their deterioration.  The advantage to these is that since a refinery may already have such fuels on site for octane or cetane testing purposes, these materials may be relatively inexpensive.  Another advantage is that, since a refiner would produce these fuels at the same site where the alternative method will be qualified, their use should minimize any difficulties associated with matrix effects.  These locally named reference fuels are not as accurate as the VCSB round robin process and are not assured by gravimetric standard reference material construction.  Thus, a refiner could only use them for relating an alternative method to a carefully calibrated installation of the designated method whose accuracy has been established and controlled by other means.
We request comment on the appropriateness of using the three types of standard reference materials for accuracy that have been discussed and on their applicability in the qualification process and statistical quality control process of analytical test methods.
Qualification Criteria of Alternative Analytical Test Methods
We are also proposing two options for refiners that wish to qualify an alternative test method as discussed in further detail in Sections VI.A.3.g.i and VI.A.3.g.ii of this proposal.  For both of the proposed options the candidate test method must have precision at least equal to that of the designated analytical test method (though not defined in precisely the same way).  And the alternative test method must be capable of correlation with the designated test method for the parameter such that the refiner may use the alternative test method results to produce predicted designated test method results that it can subsequently use in demonstrating compliance with the applicable fuel composition or performance standards.
 Statistical Quality Control Program
An important element of today's proposed approach for the qualification of alternative analytical test methods is the description of a statistical quality control (SQC) program that may be applied to any analytical test method used in the regulatory programs covered by this proposal.  We are proposing to require a SQC program as described below.  EPA's objective with statistical quality control is not to impose a complete new system of quality control measures, but rather to adopt a subset of SQC procedures that are already widely in use.  We anticipate that the measures we have selected would not require the generation of much additional data by the laboratories that elect to employ them and that the SQC program would improve the quality of measurement among those labs that adopt such measures.
      Qualification Criteria for Designated Method Installations Used to Qualify Method-Defined Parameter Instruments.
Designated test method installations that will be used to qualify method-defined parameter instruments are reference installations.  Since reference installations will be used to evaluate the accuracy of other alternative test methods and to establish correlation equations, EPA believes that these reference installations should be held to higher standards.
First, we are proposing that reference instruments meet precision qualification requirements that are similar to the criteria set forth in the nonroad diesel sulfur rule.  As explained earlier, that rule imposed a maximum value for the standard deviation of a series of at least 20 measurements over at least 20 days on a single fuel under site precision conditions.  Specifically, the diesel rule used 1.5 times the repeatability standard deviation (ASTM "r"/2.77) of what was the least precise of the then-allowed methods.  For those "method-defined" parameters from Table VI-1 above that do not currently have alternatives test methods the precision criteria is based on the fuel parameter's designated test method.  In each case the precision criterion is determined by ("r"/2.77) X 1.5 where "r" is the ASTM repeatability determined for the particular fuel that is being used for the purpose of demonstrating the test method's precision.
Second, we are proposing that such reference instruments must be shown to be near the middle of the distribution of the industry monthly inter-laboratory crosscheck (ILCC) program for at least the five months prior to application.  We are also proposing that laboratories would specifically compute the difference between the instrument's average measurement of the fuel closest to the applicable standards (or to the average value for the fuel type in the complex model) and the robust mean for that fuel obtained by all of the non-outlier labs in the program.  And then standardize this difference by expressing it in robust standard deviation units.  These standardized inter-laboratory cross check differences would be put into a moving average with a span of, for example, five months.  We are proposing to set the standard such that the instrument's moving average would be within the central 50 percent of the distribution of participating designated method labs.  Because a robust standard deviation is used by the ILCC program, this percentage will have to be approximate.  Such lab-specific qualification would be outside of the normal qualification of a lab for making regulatory measurements for certifying fuel and would pertain only to use of the instrument in certifying other methods.  In essence, these designated method installations will serve as surrogates for the gravimetric standards that cannot be used in qualifying alternative methods for method-defined parameters.
Finally, for reference installations we propose that the reference instrument must be shown to be in statistical control, as provided for in ASTM D6299-10[e1] (and the SQC procedures to be discussed below); and that the applicant must maintain control charts showing a record of in-control operation for at least five months.  While these requirements would likely impose a delay between instrument setup and the ability to qualify it as a reference installation, we believe that the delay is necessary to demonstrate the stability of these critically important installations.  Considering the number of long-established installations of these designated methods, EPA expects no lack of facilities capable of meeting these standards and able to provide this service commercially to any party interested in qualifying a new installation for a method-defined parameter.
      Qualification Criteria for Designated Test Method Installations that are "Method-Defined" Parameters Instruments and Not Used to Qualify Other "Method-Defined" Methods
Refiners, importers and oxygenate blenders producing gasoline and diesel fuel are required to test these fuels to determine the levels of various specified parameters.  A designated test method is associated with each parameter to be tested (except for sulfur concentration in ultra-low sulfur diesel fuel, which must meet performance-based requirements) in 40 CFR Part 80.  Table VI-5 of this preamble lists the fuel parameters and their corresponding designated test methods.
We are proposing today that installations of designated methods must maintain records they meet statistical quality control requirements as detailed below in this preamble.  Requiring all installations of all methods, including existing designated method installations, to implement statistical quality control, as we are proposing today, would likely suffice to homogenize and improve measurement quality in these already-stable and standardized methods.
      Qualification Criteria for Method Defined Parameter Instruments Other Than Designated Test Methods
As discussed above, the Agency is also proposing to have two options for refiners to qualify an alternative test method that is a method-defined fuel parameter.  The first option would allow for qualifying methods that have been sponsored and published by a VCSB, such as ASTM (the VCSB approach).  The second way involves qualification for a laboratory that has developed its own analytical test method but has decided not to offer it for evaluation and establishment through a VCSB-based organizational process (the non-VCSB approach).  Both options require the candidate method to have precision at least equal to that of the designated analytical test method (though not defined in precisely the same way).  The alternative method must also be capable of close correlation with the designated method for the parameter such that the refiner may use the alternative method results to produce predicted designated method results that it can subsequently use in demonstrating compliance with the applicable fuel composition or performance standards.  The proposed criteria for both the VCSB and non-VCSB approaches to qualify method-defined instruments are discussed in further detail below.
        Qualification Criteria for VCSB Method-Defined Parameter Test Methods
The first of these approaches to qualifying alternative methods applies only to methods that have been sponsored and published by a VCSB, such as ASTM.  We are proposing that the VCSB must have fully described the analytical test method, so that it is replicable in different laboratories and understood by any technician.  We would consider publication of a method by a VCSB organization such as ASTM to meet this criterion.  The VCSB must have tested the candidate method in a round robin program against the designated method, must have published a determination that the method meets the criteria specified in the discussion below, and must have published the information necessary to correlate the alternative method to the designated method.
We are also proposing that an alternative analytical test method need not be qualified separately in each laboratory that adopts it.  This is because by the time such a test method has been through the extensive development process typically required by a VCSB, the method's procedures would have been exhaustively described.  At this point there will be little uncertainty about how the analytical test method is to be applied, and it will have been implemented in a variety of different laboratories and used on a variety of different types of fuels.  Therefore the VCSB-based process gives EPA some confidence that the analytical test method is likely to be stable in use and can be implemented with very little ambiguity regarding instrumentation, materials, and procedures.  Moreover, VCSB method evaluation protocols have been established; including a protocol for comparing methods provide means for establishing a proposed VCSB alternative method's precision parity with the designated method for the parameter and for determining whether the alternative method can be adequately correlated with the designated method.  EPA is also proposing that VCSB method-defined test methods utilize ASTM D6708 to determine if a correlation equation is necessary.
        Qualification Criteria for non-VCSB Method-Defined Parameter Test Methods
The second way a candidate alternative method may qualify does not involve the process by which a VCSB evaluates and officially establish methods through publication.  EPA is proposing that a candidate method that follows the non-VCSB-based route for qualification must be qualified independently by each analytical laboratory that wishes to adopt the method.  This is because such a method has not been shown to be capable of accurately measuring the parameter in different laboratories and across a variety of fuel matrices.
The following is a discussion of the qualification criteria for non-VCSB method-defined parameter test methods.  First, the Agency proposes to require a complete operational description of the non-VCSB test method, as described above in Section VI.A.3.d.iiand VI.A.3.d.iii of this preamble.  The operational description must be thorough enough that a person lacking expertise in the operation of the test instrument would be able to replicate its results.
Second, the Agency proposes that the candidate non-VCSB test method be tested on a range of fuels  and by a qualified reference installation of the applicable designated test method.
Third, the Agency proposes that the specific laboratory using the candidate non-VCSB test method must statistically establish through application of ASTM D6708-08 that the candidate method measures the same aspect of samples as the applicable designated test method.
Fourth, the Agency is proposing to disqualify non-VCSB test methods with important sample-specific biases (matrix effects) that cannot be considered as random as determined by ASTM D6708-08.  It is possible a situation may arise where a non-VCSB test method suspected by the applicant of being highly matrix-sensitive may be qualified on a narrowly circumscribed range of fuels (which must meet the D6708-08 statistical variability criteria).  In this situation, the types of fuels on which qualification was achieved and for which the method is to be approved must be specified in the method description.  Fuels outside of this scope would have to be analyzed for regulatory purposes by some other method that was not this limited.  The Agency believes that any restriction on the scope of fuels for which the method is to be qualified must be accompanied by a discussion of how the applicant plans to screen samples for conformity to the scope.
Fifth, the Agency proposes that precision qualification be conducted in the form of cross-method reproducibility of the candidate and applicable designated test method, where the cross-method reproducibility must be equal to or less than 70 percent of the published reproducibility of the applicable designated test method.
The Agency believes, that when ASTM D6708-08 is used in this manner (without joint round robin data) the cross-method reproducibility (Rcm) output by the program is not really a reproducibility in the usual sense, but rather indicates the expected value with uncertainty of the differences between the designated method and qualification candidate method.  We believe that when used this way, Rcm from ASTM D6708-08 is more analogous to a site precision than to an inter-laboratory reproducibility.
As described, this measure can reasonably be expected to fall between the published reproducibility (R) and repeatability (r) of the designated test method.  Because qualified alternative test methods should be able to generally do as well as the designated test method Rcm be less than or equal to "R".  Since "R" is typically established when the test method is first developed, and laboratory experience with it is limited, the real reproducibility for a method long in service is likely to be smaller than "R."  Moreover, as mentioned above, Rcm is more like a site precision number, for a well-run installation, that must be smaller than "R" since the systematic component of the differences between the instruments has been adjusted out and the "within-method-interlaboratory" component of variance is not present.  On the other end of the space between "r" and "R," the published repeatability has far fewer sources of variability than any other measure of its kind, suggesting that the cut-point should be closer to "R" than to "r".  The proposed 70 percent fraction of published reproducibility was selected because there is some evidence to suggest that site precisions for various methods/parameters tend to average around that fraction of the same method's published reproducibility.  We are also requesting comment on the appropriate percentage of "R" that the "cross-method reproducibility" should be equal to or less than.
Sixth, the Agency proposes that the applicant demonstrate, through the use of ASTM D6708-08, whether a correlation to the designated test method is necessary.  ASTM D6708-08 can also be used to determine whether the candidate method's results are null compared to the designated test method and thus needs no adjustment or correlation, or whether some correction or correlation equation is required so the candidate method may predict designated method results.  We are proposing the use of ASTM 6708-08 for corrections, if it is determined through the use of ASTM D6708-08 that the candidate method requires such a correction to predict designated test method results.  The Agency proposes that the correction would be applied to the candidate instruments output to obtain measurements results for regulatory purposes.
Finally, we are proposing to require that applicants for non-VCSB test methods secure an independent third party oversight and audit review of the data generated and used to qualify non-VCSB test methods.  We are proposing that the independent third party would provide an overall assessment of the analytical technique and methodology and discuss any limitations in the scope of the method, as well as attest that all the requirements for non-VCSB test method qualification have been satisfied.  The Agency believes this requirement would provide additional assurance that a non-VCSB test method is found to be adequate in use for compliance.
We seek comments on all aspects of today's proposal. Additionally, the Agency is particularly interested in comments on the appropriateness of the qualification criteria for candidate method-defined parameter non-VCSB test methods.
      Statistical Quality Control: How Can We Ensure that Test Methods Continue to Deliver Quality Measurement in Practice?
As discussed previously, an important element of today's proposal is a statistical quality control program that may be applied to any analytical test method used in the regulatory programs covered by this proposal.  Today, the Agency is proposing that every laboratory using test instruments to measure fuel parameters must implement and maintain a basic SQC program in order to satisfy EPA's reporting or recordkeeping requirements.  We are proposing that every laboratory have a separate SQC program for each instrument used to make measurements for reporting or recordkeeping purposes.  This is unlike the qualification criteria requirements, where only one of a set of essentially identical instruments implementing the same method in a laboratory must qualify.
We are proposing that implementation of a SQC program by a laboratory would be a defense in any subsequent enforcement actions where the measurements are in use.  We are proposing to adopt a subset of SQC procedures that are already widely in use from ASTM D6299-10[e1].  We anticipate that the measures we are proposing would not require the generation of much additional data by the laboratory that employs them and that the SQC program would improve the quality of measurement among those labs that adopt such measures.  These SQC procedures used by laboratories would ensure that the test methods they have qualified and the instruments on which the methods are run are yielding results with appropriate accuracy and precision, e.g., that the results from a particular instrument does not "drift" over time to yield unacceptable values.  The proposed minimum specific SQC requirements for laboratories that measures absolute parameters, and both VCSB and non-VCSB methods used to measure method-defined parameters, are discussed in further detail below.
        Statistical Quality Control for Absolute Parameters
We are proposing precision and accuracy SQC requirements for each instrument used to measure absolute parameters in the laboratory.  We are proposing that every instrument would test a quality control ("QC") material either of: once per 20 production tests or once per week and maintain both an "I" chart and an "MR" chart.  We are proposing that any violations of the control limit(s) would be investigated by laboratory personnel, corrective action taken as required, and records kept of the incident for a period of 5 years.  We are also proposing to follow the procedures of ASTM D6299-10[e1] for making transition from one batch of QC material to another.  We are a also proposing the use of Annex A1.9, entitled "Q-Procedure," of ASTM D6299-10[e1] for validating new QC material.  We are proposing that when QC material is soon-to-be-depleted, that a new batch of QC material is prepared and its value compared to the old QC material on a chart.  The new batch of QC material would be tested concurrently with the soon-to-be-depleted old QC material.  The results would be plotted from the "old" and "new" QC materials on its respective chart, and if no special-cause signals are noted, then the result for the new material would be considered valid.
We are proposing to require that every instrument tests a commercially available gravimetric standard reference material (SRM) ("check standard" as defined in ASTM D6299-10[e1]) on a quarterly basis.  The absolute difference between the mean of multiple back-to-back tests of the SRM and ARV of the SRM greater than 0.75 times the published reproducibility of the test method must be investigated by laboratory personnel, appropriate action taken, and records kept of the incident and investigation.  We are proposing that records of the SRM measurements and investigations into any exceedances of these proposed criteria must be kept for a period of 5 years.  Additionally, we are proposing to require laboratories to pre-treat and assess results from the check standard testing after at least 15 testing occasions,  construct "MR" and "I" charts with control lines, and maintain control charts, logging, investigating, and correcting the underlying causes of any control limit violations as discussed in ASTM D6299-10[e1].  We are proposing that records of such incidents and the underlying control charts must be kept by the facility for a period of 5 years.
        Statistical Quality Control for VCSB-Approved Methods Used to Measure Method-Defined Parameters
We are proposing precision and accuracy SQC requirements for every instrument used in VCSB-approved methods to measure method-defined parameters in the laboratory.  With regard to precision, we are proposing the same SQC for instruments used for absolute parameters.  We are proposing that every instrument test a quality control QC material once every 20 production tests or once per week whichever is more frequent. We are also proposing the maintenance of an "I" chart and a "MR" chart.  We are proposing that violations of the control limit(s) in these charts would be investigated, corrective action taken as required, and records kept of the incident for a period of 5 years.  We are also proposing that laboratories follow the procedures of ASTM D6299-10[e1] for making the transition from one batch of QC material to the next.
With regard to accuracy we are proposing that each laboratory perform a check standard for each instrument as defined in ASTM D6299-10[e1] for each instrument on a quarterly basis.  We propose that check standards for "method-defined" parameters must be ordinary fuels with levels of the parameter of interest close to either regulatory standards or to the average level of use.  We also propose that ARVs of such standards must be determined through consensus methods on designated method instruments.  The absolute difference between the mean of multiple back-to-back tests of the SRM and ARV of the SRM greater than 0.75 times the published reproducibility of the test method must be investigated, appropriate action taken by laboratory personnel, and records kept of the incident and investigation.  We are proposing that records of the SRM measurements and investigations into any exceedance of the criteria must be kept for a period of 5 years.  Additionally, we are proposing that laboratories must pre-treat and assess results from the check standard testing after at least 15 testing occasions, construct "MR" and "I" charts with control lines, and maintain control charts, logging, investigating, and correcting the underlying causes of any control limit violations as discussed in ASTM D6299-10[e1].  We are proposing that records of such incidents and the underlying control charts must be kept by the laboratory for a period of 5 years.
        Statistical Quality Control for Non-VCSB Methods Used To Measure Method-Defined Parameters
We are also proposing precision and accuracy SQC requirements for instruments used in non-VCSB methods to measure method-defined parameters in the laboratory.  We are proposing precision requirements for instruments used in these types of test methods that are the same as those proposed for absolute parameters.  We are proposing that every instrument be tested on a quality control "QC" material once per 20 production tests or once per week, whichever is more frequent.  We are also proposing the maintenance of an "I" chart and a "MR" chart.  We are proposing that violations of the control limit(s) in these charts should be investigated, corrective action taken as required, and that records of the incident must be kept for a period of 5 years.  We are proposing that laboratories follow the procedures of ASTM D6299-10[e1] for transitioning from one batch of QC material to the next.
The proposed accuracy requirement depends on whether the method-defined parameter test method has minimal matrix interferences or whether the method-defined parameter test method is highly sensitive to matrix composition.  The Agency believes that non-VCSB test methods are expected to vary considerably to the extent that their results are sensitive to fuel characteristics other than the level of the analyte of interest.  For methods judged by their operators to be relatively insensitive to such matrix effects, EPA believes that the same SQC accuracy approach used with VCSB-approved methods measuring "method-defined" parameters is appropriate.  Where this is the case, a statement to this effect must be included in the application for qualification.  Any decision to abandon this approach to SQC accuracy must be reported to EPA along with the data and reasoning that led to the conclusion.
For non-VCSB methods used to measure method-defined parameters that are highly sensitive to matrix composition, we are proposing the same accuracy requirements that must be maintained as for other methods for method-defined parameters, except that the check standards will consist of production fuels, representative of those production fuels routinely analyzed by the laboratory, that have been submitted to a reference installation of the designated test method.  We are proposing that the designated test method measurements should be replicated and the average of these results used as the ARV for the check standard.  Additionally, we are proposing that the laboratory operating the alternative method is responsible for the qualification status and current stability of the reference method installation (for example, documentation on the identity of the reference installation and its control status must be maintained on the premises of the laboratory that is using the alternative test method).
Also for non-VCSB methods, the Agency is proposing external checks on the accuracy of matrix-sensitive methods.  Laboratories that have qualified such a method would be required to send a sample of each 20[th] production batch of gasoline or diesel fuel to EPA's Ann Arbor laboratory, along with the lab's measurement results using the alternative method (the result used to certify the batch).  The EPA lab may return such a sample on a blind basis for a required reanalysis by the originating laboratory at any time up to two months from EPA's receipt of the sample.  This external control is an additional check on both the site precision of the alternative method and its accuracy.  We request comments on all aspects of our proposal.
Agency Approval Options
We are proposing to require qualification of only non-VCSB test methods for fuel parameters. We are also seeking comment on whether we should require qualification of all test methods for fuel parameters.  We are also proposing a requirement for regulated parties to identify the test method used for each compliance measurement as part of the applicable record keeping and reporting.  The following section contains a discussion of our proposal
We believe that the proposed approach to performance-based qualification of test methods goes considerably beyond the minimum requirements of the NTTAA in providing flexibility of method choice, and accomplish performance-based qualification without compromising measurement quality.  We also believe that the primary tools for achieving the latter objective are lab-specific qualification of method installations and a requirement for across-the-board SQC.  While EPA would benefit from finalizing today's proposal by no longer having to evaluate new alternative measurement methodologies, this benefit is not likely to offset the substantial and unpredictable resource costs involved in administering a qualification process and providing infrastructural support for laboratories' SQC programs.
        Agency Approval of Only Non-VCSB Methods
We are proposing that only non-VCSB test methods for fuel parameters would need to be qualified.  We are proposing to exclude designated test methods that have been in operation 6 months prior to finalizing this rule, as discussed below, as well as test methods that are developed by VCSBs, like ASTM International or the International Organization for Standards (ISO).  A laboratory that has developed a test method but has decided not to offer it for evaluation and establishment through a VCSB-based organizational process would be required to qualify the test methods using the process discussed earlier.  We are proposing that such test methods must be qualified independently by each analytical laboratory that wishes to adopt the test method.  This is because such a test method has not been shown to be capable of accurately measuring the parameter in different laboratories and across a variety of fuel matrices. The precision for the candidate analytical test method must be established by a medium-term series of measurements on production fuels, the workability of the test method must be verified by at least one other laboratory, and its accuracy must be demonstrated by direct correlation to the designated analytical test method for the particular fuel parameter.
 We are proposing the following requirements for test methods that have been sponsored and published by a VCSB such as ASTM or ISO.  The test method must be fully described so that it is replicable in many different laboratories and so that its operation may be understood by a technician.  The VCSB must have tested the candidate test method in a round robin program against the designated test method, must have published a determination that the test method meets the performance criteria as discussed, and must have published the information necessary to correlate the alternative test method to the designated test method.
We are proposing a system of self-qualification for VCSB-based alternative test methods.  Thus, we are also proposing that a VCSB-based candidate alternative test method need not be qualified separately in each laboratory that adopts it.  This is because by the time a VCSB-based candidate alternative test method has been through the extensive development process typically required by a VCSB, the test method's procedures will have been exhaustively described.  At this point there will be little uncertainty about how the analytical test method is to be applied, and it will have been implemented in a variety of different laboratories and used on a variety of different types of fuels.  Therefore, the VCSB-based process gives EPA some confidence that the analytical test method is likely to be stable in use and can be implemented with very little ambiguity regarding instrumentation, materials, and procedures.
VCSB method evaluation protocols have been established, including a recently developed protocol for comparing methods, which provide means for establishing a proposed VCSB alternative method's precision parity with the designated method for the parameter and for determining whether the alternative test method can be adequately correlated with the designated test method.
We also recognize that imposing this qualification requirement on existing test methods developed by a VCSB without adequate lead time may be problematic.  We are thus proposing to give methods published and in operation when this proposal is published a grace period of one year from the effective date of a final rule before they meet these proposed requirements.
We are also proposing to exempt existing (i.e., in use for six months prior to publication of this proposal) installations of designated test methods that are method-defined parameters from the qualification requirement.  We presume these to be stable and capable methods in relatively experienced hands.  Because they are already being used to certify fuels, requiring their qualification could be disruptive and burdensome to both their operators and to whoever manages the qualification process.  Such installations would not benefit tangibly from this rule (as by obtaining access to a desired new method), but would nevertheless bear a newly-imposed burden.
We are also proposing to require record keeping and retention requirements for both VCSB alternative and non-VCSB test methods.  Parties would need to maintain qualification records for demonstrating compliance for a period of 5 years after they cease use of the particular test method.  Parties must also maintain a complete description of the test method and data with statistical analysis that supports its qualification.
We are also seeking comment on whether the Agency should require qualification of all analytical test methods for the fuel parameters at 40 CFR 80.  This would include each designated test method, all alternative test methods currently allowed by our regulations, as well as any other analytical test method regardless of whether the test method was developed by a voluntary consensus standards based organization, like ASTM, or if it is a proprietary analytical test method, that is, non-VCSB test method.
We recognize that imposing the qualification requirement on existing and operational installations of all methods without adequate lead time may be problematic.  We are thus proposing to give such laboratories (i.e., those in operation when this proposal is published) a grace period of one year from the effective date of the final rule before they must have qualified if they wish to continue in operation.  We believe that a year should be enough time to determine whether an existing test method is likely to qualify or to adopt and qualify a replacement test method if it should fall short.  New installations of previously accepted methods, including alternatives, would be required to qualify their laboratory before being put into service just like all other installations of new test methods in a laboratory.
Downstream Pentane Blending
	The current regulations at 40 CFR 80.82 reduce the burden of compliance with EPA gasoline quality requirements for parties that blend butane into conventional gasoline, reformulated gasoline (RFG), or reformulated blendstock for oxygenate blending (RBOB) downstream of a crude oil refinery.  Parties that conduct such butane blending are considered a refiner, however, they are not subject to sampling testing requirements that would otherwise apply to a refiner provided they use butane of known quality and meet certain other requirements.  Butane blending is not allowed into RFG or RBOB from April 1 through September 30 or into any RFG or RBOB that is designated as VOC-controlled.  Butane blenders must test to ensure that the volatility requirements of the final gasoline blend are met.  Testing to demonstrate compliance with other gasoline compositional requirements is not required provided that the blender has documents from the supplier demonstrating the butane is "commercial grade".  Commercial grade butane is currently defined as butane for which test results demonstrate that it is 95 percent pure and has the following properties: sulfur <= 30 ppm, benzene <= 0.03 volume percent, olefins <= 1.0 volume percent, and aromatics <= 2.0 volume percent.  Documents from the supplier demonstrating the butane is "non-commercial grade" may also be used to demonstrate compliance with gasoline quality requirements other than volatility provided the blender conducts a quality assurance program on the butane they blend.   Non-commercial grade butane is currently defined as follows: sulfur <= 30 ppm, benzene <= 0.03 volume percent, olefins <= 10.0 volume percent, and aromatics <= 2.0 volume percent.  Today's action is proposing to amend these butane specifications to replace the current 30 ppm sulfur cap with a 10 ppm cap consistent with today's proposed 10 ppm refinery average sulfur standard.
Butane blenders stated that broadening the downstream butane blending provisions to include pentane would help to increase the domestic supply of gasoline by providing a market for the pentane fraction of natural gasoline liquids.  A substantial increase in the production of natural gasoline liquids is occurring as a by-product of increased domestic natural gas and crude oil production in the U.S.  Given the lower volatility of pentane compared to butane, a greater volume of such domestically-available feedstocks could be blended into gasoline downstream of the refinery while still maintaining the gasoline quality specifications including RVP.  We request comment on whether the provisions for butane blending might also be applied to pentane blending, including the specifications for the fuel qualities noted above.  Specific comment is requested on the potential vehicle emissions and operability effects from such pentane blending.  To the extent that pentane blending might displace butane blending, there may be some decrease in evaporative emissions due to pentane's lower boiling point compared to butane.  Therefore, we anticipate that allowing downstream blending of pentane would have a neutral or marginally beneficial effect on vehicle emissions.  If we were to extend the downstream butane blending provisions to pentane, we also seek comment on whether any additional pentane quality specifications or blending requirements would be necessary to protect vehicle emissions and operability performance.
Engine, Vehicle and Equipment Programs
We are proposing several technical amendments to existing regulatory requirements for motor vehicles and other types of vehicles and engines.  These changes are intended to align with the Tier 3 standards proposed in this rule and to make various adjustments and corrections to the regulations.  We are also proposing to remove large portions of obsolete regulatory text and update cross references accordingly.  We request comment on all these amendments.  However, we are not requesting comment on the underlying regulatory requirements except as specifically described in this section.
Fuel Economy Labeling
EPA adopted updated fuel economy labeling requirements in 40 CFR part 600 on July 6, 2011. The label displays a smog rating based on relative emission rates for certified vehicles.  With new Tier 3 standards, this rating scale becomes less useful, since the Tier 3 standards would disallow certification to half of the existing smog ratings.  We are therefore proposing a new smog rating scale starting in model year 2018.  Manufacturers choosing to transition to the Tier 3 NMOG+NOX standards based on a percentage phase-in could continue to meet Tier 2 standards for the "phase-out" fraction of the fleet through model year 2020, but would use a new smog rating scale that lines up, to the extent possible, the Tier 2 standards with the new Tier 3 scale.  We believe it is appropriate to shift to the new scale in model year 2018 to reflect the start of Tier 3 program for the majority of vehicles.
The smog rating scale ranges from 1 to 10.  The federal Tier 3 program comprises seven different NMOG+NOX emission certification levels.  In addition, the California ZEV program for 2018 and later model years includes a unique TZEV category, which falls between a ZEV (Bin 0) and a SULEV20 (Bin 20), resulting in a total of eight emission standards.  We propose to omit rankings 2 and 4, ranking the eight emission levels in order over the remaining ratings.  Omitting ratings 2 and 4 helps convey the larger absolute differences in the g/mile standards between Bins 70 and 125 and Bins 125 and 160.
We also propose to adjust the scale again in model year 2025 so that, consistent with the fuel economy and greenhouse gas rating, the middle of the scale (a smog rating of 5 or 6) is equivalent to the fleet average standard of 0.030 g/mile for NMOG + NOx. Using this approach, we would apply a smog rating of 8 for TZEVs and omit 9 from the smog ratings.  We request comment on applying smog ratings to TZEV vehicles; in particular, we request comment on any appropriate differentiation of TZEV vehicles, such as assigning different smog ratings based on the particular SULEV exhaust emission standards or the allowance value for different all-electric range values.
We request comment on these and other alternative approaches to revising the specifications for the smog rating on the fuel economy label.  We also request comment on whether one or more transition rating scales would be appropriate to gradually adjust the smog rating scale as the fleet average standards become more stringent.
Removing Obsolete Regulatory Text
EPA regulations for highway and nonroad engines, vehicles, and equipment in many cases apply for a range of model years before being replaced by a new set of standards, requirements, and other provisions for implementing a program that changes to reflect technological innovation, changing environmental needs, new business dynamics, and other factors.
We are proposing to take steps in this rulemaking to remove substantial portions of regulatory text that no longer have any regulatory significance, generally because they have been superseded by newer provisions.  In many cases, this simply involves removing paragraphs or sections related to certifying products that no longer apply to 2004 or newer model years.  In other cases, we can remove whole subparts that apply only to engines and vehicles that have reached the end of their useful lives for the purpose of regulation.  For example, the in-use regulations from 40 CFR part 86, subpart H, applied only for 1993 through 2003 model year light-duty vehicles, light-duty trucks, and medium-duty passenger vehicles.  Also, the National LEV standards in 40 CFR part 86, subpart R (and in Appendix XIII through XVIII of part 86), applied only for 1999 through 2003 model years.  These subparts, and references to that content, can be removed from the CFR.
Similarly, the provisions of 40 CFR part 86, subpart A, applied to light-duty vehicles only through model year 2000 for light-duty vehicles and model year 2004 for light-duty trucks and chassis-certified heavy-duty vehicles.  Much of that subpart continues to apply for heavy-duty engines, so the obsolete portions must be removed more selectively.  The proposal includes removal of substantial portions of 40 CFR part 86, subpart A, to omit text that applies only for light-duty vehicles or light-duty trucks, and additional portions that do not apply for any 2004 or newer model years.
There are also instances where we are proposing to streamline the organization of regulatory sections in 40 CFR part 86.  For those places where there is a new section for a given model year where all the old provisions continue to apply, and the new section introduces a narrow additional provision, we are proposing to copy the new paragraph into the section for the older model-year provisions, with descriptive language in place to say when the new provision applies.  This consolidation would allow us to take out numerous sections that can lead to confusion for the reader.
The following sections describe additional changes to remove material.
Certification Short Test and I/M Provisions
Inspection and maintenance (I/M) programs have been implemented by state and local governments for many years.  These programs have been effective at identifying vehicles that need some kind of repair to restore vehicles' emission control systems.  In that context, they have also provided useful information to facilitate warranty coverage where defective components or systems were still covered by the manufacturer's warranty, as required by section 207 of the Clean Air Act.  In 1993, EPA adopted a requirement for the certification short test ("CST" or "cert short test").  The purpose of the cert short test was to correlate the vehicle manufacturer's certification and I/M testing.  Under this approach, the vehicle manufacturer certifies that a properly maintained and operated vehicle will pass I/M testing. When such a vehicle fails I/M during the warranty period, the manufacturer is responsible for the cost of repairs necessary to correct the problem so the vehicle can pass the I/M test.
EPA adopted requirements in 1993 for manufacturers to design and build their vehicles with OBD, which provides performance feedback for evaluating whether emission control systems are functioning properly.  This rule, combined with fleet turnover, has resulted in vehicles subject to I/M being equipped with OBD. The standard protocol for I/M programs now depends on the OBD system instead of tailpipe tests to determine which vehicles need maintenance.  Since vehicle manufacturers have to certify the performance of OBD systems as part of the certification process, the use of OBD for I/M testing also provides a basis for determining that emission repairs are covered by the manufacturer's warranty, when necessary.  For many years, manufacturers have submitted a compliance statement for certification instead of submitting data to demonstrate that they meet the standards associated with the cert short test.  Since emission measurements are no longer part of any standardized I/M testing, it has become clear that OBD systems have completely replaced the cert short test as the means of making warranty determinations for I/M testing.  We are therefore proposing in this rule to entirely remove the cert short test standards and test procedures from 40 CFR part 86, subparts O and S, and to similarly remove the emission measurement procedures from 40 CFR part 85, subpart W.
The remaining regulatory text in 40 CFR part 85, subpart W, relates only to the role of OBD testing in the determination of manufacturers' warranty obligations resulting from I/M testing.  In addition to removing material that no longer applies based on model years, we are proposing to update this remaining text in two ways.  First, we are expanding the scope to include medium-duty passenger vehicles since these vehicles are now subject to both OBD certification requirements and I/M testing.  Second, we are replacing all citations to SAE reference procedures with a cross-reference to 40 CFR 86.1806, where we already specify all the relevant OBD reference procedures.  This avoids the possibility of changing the certification procedures in a way that departs from the I/M and warranty provisions.  Since these programs are paired, there would never be a need to specify different reference procedures for the two programs.
Testing for Heavy-Duty Highway Engines
We recently completed the migration of test procedures for heavy-duty highway engines from 40 CFR part 86, subpart N, to 40 CFR part 1065.  Now that these manufacturers are all relying the new test procedures, we are proposing to eliminate the regulatory provisions that no longer apply.  This involves large portions of text in 40 CFR part 86, subpart N, that have been superseded by analogous material in 40 CFR part 1065, such as analyzer specifications, calibration procedures, calculation methods, and fuel specifications.  The obsolete text also included several references to 40 CFR part 86, subpart D, which we are also proposing to no longer print in the CFR.
We are keeping regulatory provisions in 40 CFR part 86, subpart N, that serve as the "standard-setting part" for matters related to testing, such as the duty cycles and not-to-exceed test procedures.  These provisions are unique to heavy-duty highway engines and are therefore not suitable for the general test specifications in 40 CFR part 1065.
In the case of testing in-use engines that were originally certified using the procedures in 40 CFR part 86, subpart N, we are including a regulatory provision that would allow EPA and manufacturers to continue to use the original certification procedures as a pre-approved alternate procedure.
Testing for Heavy-Duty Highway Vehicles
The regulations at 40 CFR part 85, subpart M, describe how to test heavy-duty vehicles above 14,000 lbs GVWR to demonstrate compliance with evaporative emission standards.  Most of these provisions are identical to those that apply under 40 CFR part 86, subpart B.  This can better be accomplished with appropriate references to the procedures in subpart B instead of repeating text.  Relying on references to subpart B would eliminate many pages of unnecessary printing, but it would also make it easier for us to maintain a consistent set of requirements.  Changing a provision in subpart B would automatically apply for evaporative testing of heavy-duty vehicles without making that duplicate change in subpart M.  In addition, as noted in Section IV.C, we are proposing to allow manufacturers of these vehicles to rely on an engineering analysis instead of performing new tests.  This would further reduce the need to have separate requirements spelled out for these vehicles.  The revised regulations preserve provisions that are specific to heavy-duty vehicle testing.  In particular, the heavy-duty procedure involves testing with a different driving schedule and wider speed tolerances, testing does not involve ethanol-blended test fuel, and exhaust emissions are not measured during the drive preceding the two-day diurnal emission test.
In some cases, the current regulations in subparts B and M include differences in test provisions that we are not preserving.  Some of these differences arose from changes to subpart B that were inadvertently not carried over to subpart M.  In other cases, there may have been an intentional distinction that no longer applies (such as provisions related to slippage on twin-roll dynamometers.  Perhaps the most important of these include procedures for determining road load settings and for operating manual or automatic transmissions.  Additional differences we are not preserving include gas divider specifications, SHED and dynamometer calibration procedures, and some provisions for alternative canister loading and vehicle preconditioning.  We are also restoring paragraphs §86.1235(b) through (i) related to dynamometer operating procedures, which were inadvertently removed in an earlier rulemaking.  This leaner approach for vehicles above 14,000 lbs GVWR is also consistent with our proposed change to waive evaporative testing requirements for certifying these vehicles.
Service Information Requirements for Light-Duty Vehicles
The service information regulations were originally adopted for light-duty motor vehicles 40 CFR 86.038-96.  These requirements applied for 1996 and later model year vehicles.  Starting with the 2001 model year, these same requirements were copied into §86.1808-01.  These two sets of requirements are identical except for the model year applicability and a variety of very minor stylistic differences.  We are proposing to revise the service information regulations in §86.1808-01 to apply also to 1996 through 2000 model year vehicles, and to correct several typographical and formatting errors.  These changes should have no practical significance, since the requirements are the same in both regulatory sections.
Motorcycle Driving Schedules
The CFR includes two separate driving schedules for motorcycles.  The first, for motorcycles at or above 170 cubic centimeters (cc), is identical to that used for light-duty vehicles except that the speeds are converted to kilometers per hour.  The second driving schedule, for smaller motorcycles, is also identical except for a period of about three minutes of reduced-speed operation.  To simplify this arrangement, and to make room for the new LA-92 driving schedule described in Section IV.B for heavy-duty vehicles, and also to allow for reference to m/s values as described above for light-duty vehicles, we are proposing to eliminate the identical portions of these drive schedules.  This revised approach involves referencing the driving schedule for light-duty vehicles with instructions to convert to kilometers per hour and round the resulting speeds to the nearest 0.1 kilometers per hour, instead of repeating the driving schedule just to publish the same speed trace in different units.  The unique portion of the driving schedule is laid out, with reference to the light-duty driving schedule for the portions that are unchanged.  This is not intended to cause any change in the current requirements or practices for certifying motorcycles.
Updating Reference Procedures
The regulations in 40 CFR part 1065 depend on a large number of reference procedures and technical standards from ASTM, SAE International, and ISO, among others.  These reference procedures and technical standards are updated periodically to keep them current with ongoing developments in the field.  Many times these changes include only minor corrections or clarifications.  In other cases the updates incorporate new test methods, accommodate changing engine technologies, or other more substantive changes.  Whether the updated reference documents involve major changes or not, it is important for the regulations to rely on documents that are readily available.  Toward that end, we plan to update §1065.1010 with the latest versions of all the reference procedures and technical standards that we identify.
In areas of the regulations other than part 1065, we intend to rely on the latest reference documents where we are changing or adding a provision that depends on one of these reference documents, but we do not plan in this rulemaking to make broad or universal changes to these references.
One particular area of interest relates to rounding.  As described in Section IV.F.3, we are proposing to define "round" for 40 CFR part 86 to have the meaning we give in 40 CFR 1065.20, which spells out a detailed rounding protocol that is consistent with ASTM E29 and NIST SP811.  The proposed definition of "round" will defer to existing references in part 86 so that the part 1065 protocol will apply only where we do not specifically refer to ASTM E29.  This is not intended to change the policy for calculating or reporting numerical quantities, but rather to clarify the protocol and avoid the administrative complication of referencing multiple versions of the ASTM document.
What are the Cost Impacts of the Proposed Rule?
We have estimated the costs for both the proposed vehicle standards described in Section IV and the proposed fuel standards described in Section V.  This section summarizes these costs, while further information on the methodology we used to develop these costs can be found in Chapters 2 and 5 of the draft RIA.
Section VII.C provides a summary of total costs for the proposed vehicle and fuel programs together.  We have also compared the proposed program costs to the projected emission reductions in Section VII.D and compared these cost-effectiveness estimates to those for other programs.  For a comparison of the program costs to the monetized health and welfare benefits, see Section VIII.
Estimated Costs of the Vehicle Standards
To determine the cost for vehicles, we first determined which technologies were most likely to be applied by vehicle manufacturers to meet the proposed standards assuming gasoline sulfur levels were reduced to a 10 ppm average.  These technologies were then combined into technology packages which reflected vehicle design attributes that directly contribute to a vehicle's emissions performance.  The attributes considered included vehicle type (car or truck), number of cylinders, engine displacement, and the type of fuel used (gasoline or diesel).  We also created separate packages for light-duty and heavy-duty trucks and vans.  In estimating both cost and technology application, we have relied on publicly available information (such as that developed by California), confidential information supplied by individual manufacturers and suppliers, and the results of our own in-house testing.  The technology packages that we developed represent what we consider to be the most likely average emissions control solution for each vehicle type.
In general, we expect that the majority of vehicles would be able to comply with the Tier 3 standards which we are proposing through refinements of current emissions control components and systems.  Some vehicles may require additional emission controls, such as large trucks with large displacement engines (in particular, LDT3s and LDT4s).  Overall, smaller, lighter-weight vehicles will require less extensive improvements than larger vehicles and trucks.  Specifically, we anticipate a combination of technology upgrades including:
Catalyst Platinum Group Metal (PGM) Loading.  Increased catalyst application of precious metals.
Optimized Close-coupled catalyst:  Improvements to the catalyst system design, structure, and packaging to reduce light-off time.
Optimized Thermal Management:  Overall thermal management of the emissions control system to improve to shorten the time it takes for the catalyst to light-off.
Secondary Air Injection:  Increased application of secondary air injection for some 6-cylinder and larger engines.
Engine Calibration:  Engine control and calibration modifications to improve air and fuel mixtures, particularly at cold start and/or to control secondary air and hydrocarbon adsorbers.
Hydrocarbon Adsorber:  Limited application of hydrocarbon adsorbers to trap hydrocarbons during cold start and release the hydrocarbons after the catalyst lights off.
Evaporative Emissions Controls:  Improved evaporative emissions systems, including canister scrubbers, more permeation-resistant materials, and improved system integration.
As stated above, we have developed our costs with respect to a given vehicle type and the type of engine with which it is equipped.  Although the cost of achieving the proposed Tier 3 standards will increase with the size of the vehicle and the displacement of the engine, we have concluded that the cost for each engine type is independent of the type of vehicle in which it is equipped.  For example, we estimate that the cost of catalyst loading for an in-line 4-cylinder (I4) engine will be the same whether the engine is in a car or a truck.  The final cost per vehicle is the result of not only the cost per technology, but also the application rate of that technology for each vehicle type.  For example, while the $199 (2010$) cost of secondary air injection is the same for both a 6-cylinder (V6) and 8-cylinder (V8) application, we anticipate that only 25 percent of the V6 applications will require this technology, while 75 percent of the V8 applications will require it.  Table VII-1 below shows our estimate of the cost of each of the emission control technologies for the gasoline vehicles affected by this proposed rule.  Table VII-2 provides the anticipated application rate of the technology by vehicle type.  Note that all of the costs shown in this section are in 2010 dollars, are applicable for the 2017 MY and are marked-up by an Indirect Cost Multiplier (ICM) so they include both direct and indirect costs.  (For details of regarding ICMs and their application refer to Chapter 2 of the draft RIA.)
Table VII-1  2017MY Technology Costs by Gasoline Engine Type (2010$)
Technology
                            Gasoline Engine Type[a]

                                      I4
                                      V6
                                      V8
                                   HD[c] V8
Catalyst Loading
                                      $72
                                      $95
                                     $119
                                      $60
Optimized Close-coupled Catalyst
                                      $24
                                      $48
                                      $72
                                      $72
Optimized Thermal Management
                                      $36
                                      $36
                                      $36
                                      $36
Secondary Air Injection
                                    N/R[b]
                                     $119
                                     $119
                                      N/R
Engine Calibration
                                      $2
                                      $2
                                      $2
                                      $2
Hydrocarbon Adsorber
                                      N/R
                                      N/R
                                     $201
                                      N/R
Evaporative Emissions Controls
                                      $20
                                      $20
                                      $20
                                      $20
[a] I4  -  In-line 4-cylinder, V6: 6-cylinder, V8: 8-cylinder
[b] N/R  -  Not Required
[c] Heavy-duty
Table VII-2  Technology Application Rates for Gasoline Vehicles
                                  Technology
                  Technology Application Rate by Vehicle Type

                                    I4 LDV
                                    V6 LDV
                                    V8 LDV
                                    I4 LDT
                                    V6 LDT
                                    V8 LDT
                                     HD V8
                               Catalyst Loading
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                       Optimized Close-coupled Catalyst
                                      50%
                                      60%
                                      75%
                                      50%
                                      60%
                                      75%
                                      0%
                         Optimized Thermal Management
                                      25%
                                      25%
                                      25%
                                      25%
                                      25%
                                      25%
                                      25%
                            Secondary Air Injection
                                      N/R
                                      25%
                                      75%
                                      0%
                                      25%
                                      75%
                                      N/R
                              Engine Calibration
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                             Hydrocarbon Adsorber
                                      N/R
                                      N/R
                                      15%
                                      0%
                                      0%
                                      15%
                                      N/R
                        Evaporative Emissions Controls
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%
                                     100%

Medium Duty Passenger Vehicles (MDPVs) were included in the light-duty fleet as part of Tier 2.  Given their current certification requirements for criteria pollutants, we have included the costs for MDPVs to meet the Tier 3 standards with the LDT4 cost estimates.  We do not expect that the technologies required to meet the Tier 3 standards for MDPVs will be different from those applied to LDT4s, as in many cases identical powertrains and chassis exist between the LDT4 and MDPV platforms.
We also expect that manufacturers will continue to build and sell light-duty diesel vehicles and certify those vehicles to Tier 3.  All light-duty diesel vehicles currently being sold in the federal fleet are equipped with some means of controlling NOX emissions, either a Lean NOX Trap (LNT) or SCR system.  As these systems are already very effective in controlling NOX emissions, we expect that they will remain the primary emissions control systems to meet Tier 3.   Similar to gasoline engines, diesel powertrains may be required to improve the effectiveness of their emission control systems during cold start.  Therefore, we have developed our costs for diesels with the expectation that the incremental costs will be realized to improve LNT and SCR systems during cold start.  The improvements have been categorized as general SCR optimization, which include packaging changes to the SCR system to allow faster light off; Optimized Thermal Management, to reduce the thermal mass of the system and allow more of the combustion heat to reach the SCR system sooner; and the calibration work associated with both of these changes.  Table VII-3 below describes both the cost of the technologies as well as their anticipated application rates.
 Table VII-3  2017MY Technology Costs and Application Rates for Diesel Engines (2010$)
Technology
                              Diesel Engine Costs
                                  (all types)
                  Light-duty and Heavy-duty Application Rate
Optimized Thermal Management
                                      $36
                                      25%
Engine Calibration
                                      $2
                                     100%
SCR Optimization
                                      $60
                                     100%
Costs have also been estimated for HDVs between 8,501 and 14,000 lbs GVWR.  Vehicles in this range are often referred to as Class 2b (8,5001-10,000 lbs) and Class 3 (10,001-14,000 lbs) vehicles and are typically full-size pickup truck and work vans.  We applied the same process to the heavy-duty vehicles as we did to the light-duty vehicles.  Heavy-duty costs and application rates may be found in Table VII-1, Table VII-2, and Table VII-3 above.
 We have also considered the impacts of manufacturer learning on the technology cost estimates.  We reflect the phenomenon of volume-based learning curve cost reductions in our modeling using two algorithms, depending on where in the learning cycle (i.e., on what portion of the learning curve) we consider a technology to be: the "steep" portion of the curve for newer technologies and "flat" portion of the curve for more mature technologies.  The observed phenomenon in the economic literature which supports manufacturer learning cost reductions are based on reductions in costs as production volumes increase with the highest absolute cost reduction occurring with the first doubling of production.   For additional information on technology learning refer to Chapter 2 of the draft RIA.  Learning impacts have been considered on all of the technologies expected to be used with the assumption that all technologies are on the flat portion of the learning curve.  We did not consider any of the technologies to be on the steep portion of the learning curve because none are being used for the first time in the 2017-2025 timeframe.
Finally, we have prepared our cost estimates for meeting the Tier 3 standards using a baseline of Tier 2 Bin 5 technologies for all LDVs, LDTs, and MDPVs.  The baseline fleet used for these cost estimates is the MY 2016 light-duty fleet predicted by the 2012-2016 GHG Rule.  The 2012 GHG Rule provides us with the clearest picture of what the light-duty fleet may look like in MY 2017.  Additional details on how the 2017 MY fleet (i.e., the reference case fleet for this proposal) was developed can be found in Chapter 2 of the draft RIA.  In short, the 2012-2016 GHG final rule is expected to result in considerable downsize of engines along with turbocharging to maintain performance.  Since engines are expected to be downsized, the estimated Tier 3 costs are impacted since smaller engines are expected to incur lower costs as shown in Table VII-1.
Since GHG standards for the 2017-2025 fleet have just recently been finalized, we were not able to reflect their potential impacts on the baseline fleet in this proposal.  We do not expect the MYs 2017-2025 GHG standards will change the technologies that we project will be used to comply with the proposed Tier 3 standards.  However, some of the changes to the vehicle fleet expected to result from the MYs 2017-2025 GHG standards, such as a greater penetration of downsized engines, could lower the cost of complying with Tier 3 standards.  The final Tier 3 rule will include the changes to the fleet associated with the GHG standards and the resulting impacts on cost.