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Performance-Based Measurement System (PBMS) & Flexible Approach

EPA received many questions about hazardous waste test methods. The questions and responses for this category are listed below.
 

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What is the current process to promulgate SW-846 test methods?

I understand the process has changed in promulgating SW-846 test methods. How are they promulgated? When are they finally approved for use?

Currently, many RCRA regulations specifically require the use of SW-846 methods. Methods are added to the SW-846 methods compendium by two ways. Required methods are added to SW-846 through a formal rulemaking process, in which the Agency follows the Action Development Process (ADP), through which the agency seeks notice and comment. After the comments are reviewed, the required method may be revised, based on public comment. Then Agency will finalized the methods with a Final rule after the designated comment period. Only after a final rule is published are methods approved for use by the regulated community in order to comply with RCRA regulations requiring the use of finalized SW-846 methods. States may choose to adopt the required method(s).

For all other methods considered guidance, updates to SW-846 are announced through a Notice of Availability (NOA). These validated methods are made available to the public for comment. After comments are evaluated, the agency will revise the method update appropriately. Once the methods are finalized, the update is incorporated into the SW-846 method compendium.

Other Categories: General, MIR & MDPs

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How can one determine when a non-required method is appropriate to use for compliance with RCRA in relation to the Methods Innovation Rule?

How can one determine when a non-required method is appropriate to use for compliance with RCRA in relation to the Methods Innovation Rule?

If the analysis that you wish to perform is not for one of the Method Defined Parameters (MDPs) listed in 40 CFR §260.11, then you must determine whether a method (whether SW-846 or not) is appropriate for the analytical purpose. The Agency has written the following guidance in the MIR for determining method appropriateness:

  • An appropriate method might be one published by:
  • EPA in a different manual or regulation;
  • Another government agency;
  • A voluntary standards setting organization; or
  • Other well-known source.

Appropriate methods are reliable and accepted as such in the scientific community. These methods might include those published by the Agency or other government entities using techniques that have documented reliability (e.g., ASTM).

Appropriate methods generate effective data, known and of appropriate quality for project-specific decisions.

When selecting an appropriate method to use, you must be able to demonstrate and document that you are able to see the analyte of concern, in the matrix of concern, at the level of concern.

In addition, before selecting an alternative method other than SW-846 for RCRA-related testing and monitoring activities, we recommend that you discuss your plans with your regulating authority and the project managers.

Other Categories: General, MIR & MDPs

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Do the "flexible approach", performance based measurement system (PBMS), and/or Methods Innovation Rule (MIR) change the way prescriptive language is interpreted in SW-846 methods?

The following statement from the Disclaimer for SW-846 provides specific guidance for interpretation of must, should, etc.:

"EPA generally does not intend these methods to be overly prescriptive. The words "shall," "must," or "require" are used to indicate aspects of the method that are considered essential to its performance, based on sound analytical practices (e.g., an instrument must be calibrated before use). In contrast, the words "should," "may," or "recommend" are used to provide guidance on aspects of the method that are useful but not essential. This flexibility does not apply to those Method Defined Parameters where the analytical result is wholly dependent on the process used to make the measurement."

Other Categories: General, MIR & MDPs

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What is the "flexible approach" for environmental measurement?

In 2008, EPA gauged its progress towards achieving the goals of PBMS, and redefined the steps needed to ensure continued progress. As a result of this analysis, the Agency now believes that while it may be possible to specify performance criteria in a manner that is independent of methods, techniques, or instruments, the development of a single protocol for the validation of all current and future measurements, including measurements made with techniques yet to be invented, is simply not possible. Accordingly, in February 2008 EPA introduced flexible approaches for environmental measurement which capture the Agency's experience of the past ten years and set the stage for future progress.

Key goals for these flexible approaches are as follows:

  1. Increased emphasis on flexibility in choosing sampling and analytical approaches to meet regulatory requirements for measurements.
  2. Development of processes for validation that confirm that measurements meet quality requirements.
  3. Increased collaboration with stakeholders to develop validation processes for new measurement technology.
  4. Rapid assessment of new or modified technologies, methods and procedures.

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What is EPA doing to implement a Performance Based Measurement System (PBMS)?

Assuring the quality of environmental measurements is essential to implementation of EPA's environmental programs, both regulatory and voluntary. In a 1997 Notice of Intent, the Agency outlined a "Performance Based Measurement System (PBMS)" concept that was intended to "improve data quality and encourage advancement of analytical technologies.”

As part of EPA's effort to implement the PBMS approach, the following actions were taken:

Incorporating the PBMS philosophy into new regulations.

Establishing data quality and performance requirements for RCRA-required monitoring and including the requirements in the RCRA regulations, as necessary, to assist the regulated community in method selection and help assure successful PBMS implementation.

Developing new sampling and testing methodologies which are compatible with the PBMS approach and encouraging use of those methods.

Fostering training and guidance to educate regulators and the regulated community regarding the flexibility of PBMS, the inherent flexibility of SW-846, and application of PBMS during RCRA-related monitoring.

Removing some of the required uses for SW-846 methods from RCRA regulations, where the Agency believes these requirements are not necessary (in order to facilitate PBMS implementation), and thus removing regulatory barriers to the use of new and innovative technologies for RCRA-related monitoring.

In 2008, EPA gauged its progress towards achieving the goals of PBMS, and redefined the steps needed to ensure continued progress. As a result of this analysis, the Agency now believes that while it may be possible to specify performance criteria in a manner that is independent of methods, techniques, or instruments, the development of a single protocol for the validation of all current and future measurements, including measurements made with techniques yet to be invented, is simply not possible. Accordingly, in February 2008 EPA introduced flexible approaches for environmental measurement which capture the Agency's experience of the past ten years and set the stage for future progress.

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What are the benefits of EPA's Performance Based Measurement System (PBMS)?

The PBMS approach would provide many benefits to both regulators and the regulated community, including:

  • Flexibility in method selection.
  • Expedited approval of new and emerging technologies to meet mandated monitoring requirements.
  • Development and use of cost-effective methods that meet program requirements and their associated performance criteria.
  • Where PBMS is implemented, the regulated community will be able to select an appropriate analytical method for use in complying with the RCRA regulations, including a method not found in EPA-published manuals that is cost-effective and meets the particular project criteria.

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How does EPA's Performance Based Measurement System (PBMS) approach affect SW-846?

Due to the complexities in material and waste characterization in support of RCRA, SW-846 functions under the Performance Based Approach (PBMS), and flexibility (in choosing sampling and analytical approaches to meet measurement requirements) is allowed when it is appropriate to do so. PBMS conveys "what" needs to be accomplished, but not prescriptively "how" to do it. EPA defines PBMS as a set of processes wherein the data needs, mandates, or limitations of a program or project are specified, and serve as criteria for selecting appropriate methods to meet those needs in a cost-effective manner. The criteria may be published in regulations, technical guidance documents, permits, work plans, or enforcement orders. Under a performance-based approach, EPA would specify:

  • Questions to be answered by monitoring.
  • Decisions to be supported by the data.
  • Level of uncertainty acceptable for making decisions.
  • Documentation to be generated to support this approach in the RCRA monitoring program.

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Why use a Performance Based Measurement System (PBMS)?

In 1997, the Agency adopted the Performance Based Measurement System (PBMS) (i.e., Federal Register Notice of Intent) to:

  • Reduce the cost of monitoring;
  • Stimulate the development and use of innovative technologies;
  • Speed up the introduction of new methods; and
  • Improve the quality of science in the monitoring community.

Unfortunately, the "one size fits all" approach did not work for the diversely different programs and authority within each Agency office. The guidance document “Flexible Approaches to Environmental Measurement”, created in 2008 shifted the focus from the performance approach to a more flexible one. Documentation on the Agency’s commitment to this flexible approach can be found on the EPA's Environmental Measurements and Modeling page.

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