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Set Aside Treatability Guidelines. Brent Means U.S. Office of Surface Mining. Introduction. The SA program is ~ 14 years old. The AML reauthorization provides an opportunity and reason to perform a review of the SA program.
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Set Aside Treatability Guidelines Brent Means U.S. Office of Surface Mining
Introduction • The SA program is ~ 14 years old • The AML reauthorization provides an opportunity and reason to perform a review of the SA program • The workgroup was formed to produce guidelines that would form the basis for future project selection • The guidelines contain both project selection and treatability criteria
Project Selection and Treatability Document: Guiding Principals Achieving and maintaining restoration is most important SA program should be expanded to consider any type of treatment (not just passive) Restoration should be done in a “comprehensive” manner
Treatability Criteria • The goal of the criteria is to ensure the proposed treatment or abatement strategy is an appropriate match for the water quality and site conditions • The treatability scoring is based on three evaluations: • A “Proven” evaluation: focused on evaluating whether the proposed scenario is proven to provide treatment • A “Reliability” evaluation: an operational evaluation • A “Predictable” evaluation: a maintenance evaluation • The proposed treatment project is evaluated against the criteria for each of the three assessments, resulting in an overall score for the Treatability section of the document
Proven Evaluation A “proven” technology is a treatment or abatement technique that: • is successfully used at numerous locations under treatment scenarios similar to the proposed project; • is sized or manufactured using a science-base approach that can be evaluated • has a data-supported performance record
Reliable Evaluation A “reliable” treatment or abatement technology is one that: • Can achieve the treatment/abatement goals > 90% of the design life; • Can be operated and maintained to consistently achieve treatment/abatement goals; • Can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions;
Predictable Evaluation A “predictable” treatment or abatement technology is one that: • contains troubleshooting capacity; • can be maintained or rehabilitated if the treatment/abatement goals are not being achieved; • has maintenance flexibility built into the treatment scheme;
Set Aside projects are arranged into 6 Categories • Active Treatment • Passive Treatment of Net Alkaline discharges • Passive Treatment of Net Acidic discharges using ALD • All other types of Passive Treatment for Net Acidic water • Innovative Technology • Abatement projects • All SA projects fit into one of these categories and evaluated against the “Proven”, “Reliable,” and ‘Predictable” scoring criteria
Example using Active Treatment Proven Evaluation: • is successfully used at numerous locations under treatment scenarios similar to the proposed project; • is sized or manufactured using a science-base approach that can be evaluated • has a data-supported performance record ** Can automatically receive a high proven score if it is commonly used to achieve water quality based standards in similar situations • Other factors that affect the “Proven” evaluation
Example using Active Treatment • Other factors that affect “Reliability” evaluation: • Ability to achieve treatment goals under the range in hydrologic and geochemical conditions characterized at the site • Ability to continue treatment during desludging • Ease of operation Reliable Evaluation (deals with operational issues) : • Evaluate the likelihood that the recommended system can achieve the treatment/abatement goals > 90% of the design life; • Evaluate whether the proposed system can be operated and maintained to consistently achieve treatment/abatement goals; • Evaluate whether the proposed system can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions • Evaluate whether the proposed system be operated to achieve varying degrees of treatment
Example using Active Treatment Predictability Evaluation (deals with maintenance issues) : • Evaluate the whether the proposed system contains the capacity to easily troubleshoot operational problems; • Evaluate whether the proposed system can be easily maintained or rehabilitated if the treatment/abatement goals are not being achieved; • Evaluate whether the proposed system contains maintenance flexibility built into the treatment scheme; • Other factors that affect the “Predictability” evaluation • Time frame between chemical replenishment • Time frame between desludging events • Sludge handling • Longevity of sludge storage volume
Treatability Evaluation • Active Treatment - covered • Passive Treatment of Net Alkaline Discharges • Promoted by automatically receiving a high “proven” score • Scoring is affected by sludge handling, sludge storage volume, addresses the effects of temp., etc. • Passive Treatment of Net Acidic Discharges using ALDs • Promoted by automatically receiving a high “proven” score • Ease of troubleshooting system, sludge handling, rehabilitation plan • All other types of passive treatment for Net Acidic discharges using passive Treatment
Treatability Evaluation • All other types of passive treatment for Net Acidic discharges using passive Treatment Proven Evaluation: • Discharge characteristics are compared against risk matrix to obtain a score • Risk Matrix was developed on the premise that passive treatment (e.g. VFP) best performs (longevity, maintenance) on low-loading discharges • The intent of the risk matrix is to provide a structured approach for project selection that would be continuously refined as projects are completed and performance is field-validated
All other Passive Treatment on Net Acidic water • Other factors that affect “Reliability” evaluation: • Ability to control flow into the system • Ease of treatment operation • Ability to continue treatment during desludging or rehabilitation events Reliability Evaluation: • Evaluate the likelihood that the recommended system can achieve the treatment/abatement goals > 90% of the design life; • Evaluate whether the proposed system can be operated and maintained to consistently achieve treatment/abatement goals; • Evaluate whether the proposed system can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions • Evaluate whether the proposed system be operated to achieve varying degrees of treatment
All other Passive Treatment on Net Acidic Water • Other factors that affect the “Predictability” evaluation • Ability to monitor the progression of plugging • Ease of troubleshooting treatment system • Time frame between rehabilitation events • A plan to dispose of compost or limestone Predictability Evaluation (deals with maintenance issues) : • Evaluate the whether the proposed system contains the capacity to easily troubleshoot operational problems; • Evaluate whether the proposed system can be easily maintained or rehabilitated if the treatment/abatement goals are not being achieved; • Evaluate whether the proposed system contains maintenance flexibility built into the treatment scheme;
Treatability Evaluation • Innovative Technology • AML money is not permitted for “research” activities • Innovative Technologies would be subject to a “proven, reliability (operation), and predictability (Maintenance)” evaluations • Abatement Projects • Abatement Projects would be subject to a “proven, reliability (operation), and predictability (Maintenance)” evaluations • The background data should be sufficient enough to show the cause/effect relationship between the mining feature and the affected water resource