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

SA program should be expanded to consider any type of treatment (not just passive)

Achieving and maintaining restoration is most important

Restoration should be done in a “comprehensive” manner

• 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

Treatability Criteria

• The treatability scoring is based on three evaluations:

1. A “Proven” evaluation: focused on evaluating whether the proposed scenario is proven to provide treatment

2. A “Reliability” evaluation: an operational evaluation

3. 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

1. is successfully used at numerous locations under treatment scenarios similar to the proposed project;

Proven Evaluation

2. is sized or manufactured using a science-base approach that can be evaluated

3. has a data-supported performance record

A “proven” technology is a treatment or abatement technique that:

1. Can achieve the treatment/abatement goals > 90% of the design life;

A “reliable” treatment or abatement technology is one that:Reliable Evaluation

2. Can be operated and maintained to consistently achieve treatment/abatement goals;

3. Can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions;

1. contains troubleshooting capacity;

Predictable Evaluation A “predictable” treatment or abatement technology is one that:

2. can be maintained or rehabilitated if the treatment/abatement goals are not being achieved;

3. has maintenance flexibility built into the treatment scheme;

Set Aside projects are arranged into 6 Categories

1. Active Treatment

2. Passive Treatment of Net Alkaline discharges

3. Passive Treatment of Net Acidic discharges using ALD

5. Innovative Technology

6. Abatement projects

• All SA projects fit into one of these categories and evaluated against the “Proven”, “Reliable,” and ‘Predictable” scoring criteria

4. All other types of Passive Treatment for Net Acidic water

Example using Active Treatment

Proven Evaluation:

** Can automatically receive a high proven score if it is commonly used to achieve water quality based standards in similar situations

1. is successfully used at numerous locations under treatment scenarios similar to the proposed project;

2. is sized or manufactured using a science-base approach that can be evaluated

3. has a data-supported performance record

4. Other factors that affect the “Proven” evaluation

Example using Active Treatment

Reliable Evaluation (deals with operational issues) :

3. Evaluate whether the proposed system can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions

2. Evaluate whether the proposed system can be operated and maintained to consistently achieve treatment/abatement goals;

1. Evaluate the likelihood that the recommended system can achieve the treatment/abatement goals > 90% of the design life;

4. Evaluate whether the proposed system be operated to achieve varying degrees of treatment

Ability to continue treatment during desludging

Ability to achieve treatment goals under the range in hydrologic and geochemical conditions characterized at the site

Ease of operation

5. Other factors that affect “Reliability” evaluation:

Example using Active Treatment

Predictability Evaluation (deals with maintenance issues) :

Sludge handling

Time frame between chemical replenishment

3. Evaluate whether the proposed system contains maintenance flexibility built into the treatment scheme;

2. Evaluate whether the proposed system can be easily maintained or rehabilitated if the treatment/abatement goals are not being achieved;

1. Evaluate the whether the proposed system contains the capacity to easily troubleshoot operational problems;

4. Other factors that affect the “Predictability” evaluation

Time frame between desludging events

Longevity of sludge storage volume

1. Active Treatment - covered

Treatability Evaluation

4. All other types of passive treatment for Net Acidic discharges using passive Treatment

3. Passive Treatment of Net Acidic Discharges using ALDs

2. Passive Treatment of Net Alkaline Discharges

Scoring is affected by sludge handling, sludge storage volume, addresses the effects of temp., etc.

Promoted by automatically receiving a high “proven” score

Promoted by automatically receiving a high “proven” score

Ease of troubleshooting system, sludge handling, rehabilitation plan

Treatability Evaluation

4. 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

Summation of Fe and Al Concentration

< 25 gpm > 25 < 50 gpm > 50 < 100 gpm > 100 < 200 gpm

< 5 Very Low Very Low Very Low Low< 15 mg/L Low Moderate Moderate High

> 15 < 25 mg/L Low Moderate Moderately High High > 25 < 50 mg/L Moderate Moderately High High Very High

> 50 mg/L Very High Very High Very High Very HighSummation of Fe and Al

Concentration > 200 < 400 gpm > 400 < 800 gpm > 800 < 1600 gpm > 1600 gpm

< 5 Moderate Moderate Moderately High Very High< 15 mg/L Very High Very High Very High Very High

> 15 < 25 mg/L Very High Very High Very High Very High> 25 < 50 mg/L Very High Very High Very High Very High

> 50 mg/L Very High Very High Very High Very High

Design Flow Rate for each treatment cell

Design Flow Rate for each treatment cell

Risk Analysis Matrix

All other Passive Treatment on Net Acidic water

Reliability Evaluation:

3. Evaluate whether the proposed system can be manipulated to achieve treatment/abatement goals under varying flow, chemistry, and operational conditions

2. Evaluate whether the proposed system can be operated and maintained to consistently achieve treatment/abatement goals;

1. Evaluate the likelihood that the recommended system can achieve the treatment/abatement goals > 90% of the design life;

4. Evaluate whether the proposed system be operated to achieve varying degrees of treatment

Ability to control flow into the system

Ease of treatment operation

Ability to continue treatment during desludging or rehabilitation events

5. Other factors that affect “Reliability” evaluation:

All other Passive Treatment on Net Acidic Water

Predictability Evaluation (deals with maintenance issues) :

3. Evaluate whether the proposed system contains maintenance flexibility built into the treatment scheme;

2. Evaluate whether the proposed system can be easily maintained or rehabilitated if the treatment/abatement goals are not being achieved;

1. Evaluate the whether the proposed system contains the capacity to easily troubleshoot operational problems;

Time frame between rehabilitation events

Ability to monitor the progression of plugging

4. Other factors that affect the “Predictability” evaluation

Ease of troubleshooting treatment system

A plan to dispose of compost or limestone

Treatability Evaluation

5. Innovative Technology

AML money is not permitted for “research” activities

Innovative Technologies would be subject to a “proven, reliability (operation), and predictability (Maintenance)” evaluations

5. 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

THE END