# Presentation: 146971

## Filter Backwash Recycling Rule

** ****Final:  June 8, 2001**

- FBRR

## Background

- Filter backwash recycle reintroduces contaminants back into the treatment process
- 1996 SDWA Amendments require EPA to promulgate a regulation that “governs” recycle of filter backwash water within a treatment plant

**Notes:**
The main objective of the FBRR is to improve performance at filtration plants by reducing the opportunity for recycle practices to adversely affect plant performance in a way that would allow microbes such as Cryptosporidium to pass through into finished drinking water.  

## Purpose of FBRR

- Recycle streams are source of high concentration of microbial pathogens and chemical contaminants
- Contribute to the contaminant load
- Coagulant chemistry imbalance
- Hydraulic surge--overwhelms plant’s unit processes
- Waste flows may adversely affect plant performance and, subsequently, pathogen removal

**Notes:**
Contaminants in the recycle stream, particularly Cryptosporidium, can affect finished water quality.
Residual chemicals and other contaminants in the recycle stream can upset chemical feed processes in the main treatment train process, affecting the coagulation process and contaminant removal in subsequent treatment processes.
Recycle streams can be reintroduced in sufficient volumes (such as spent filter backwash) to create an hydraulic surge or cause  plant capacity exceedance issues.
All of these issues have the potential to impact finished water quality.

## Purpose of FBRR

- FBRR reduces potential for Cryptosporidium oocysts to pass through filters into finished water by ensuring proper management of residual streams
- FBRR also allows States to evaluate recycle practices and identify any potential problems.

**Notes:**
States will need to assess recycle practices of systems regulated under the FBRR to make sure recycle practices are not affecting finished water quality.
States will evaluate information submitted and collected by systems to assess recycle practices.  States will want to identify recycle practices that may or are causing finished water quality issues (such as turbidity levels in excess of allowed limits).

## Systems Covered by FBRR §141.76(a)

**Systems Covered by FBRR §141.76(a)**

- SW and GWUDI (Subpart H) systems that employ conventional or direct filtration and
- Recycle one or more of the following:
- Spent filter backwash water
- Thickener supernatant
- Liquids from dewatering processes

**Notes:**
The Filter Backwash Recycling Rule applies to all surface water or ground water systems under the direct influence of surface water that practice conventional (coagulation, flocculation, sedimentation, and filtration) or direct filtration (coagulation, flocculation, and filtration), and that recycle at least one of the three specific streams above.

These three recycle streams were selected for regulation because they are produced in large volumes (such as spent filter backwash) and may cause a plant upset and/or they have the potential to contain high concentrations of Cryptosporidium oocysts. 

## Conventional Treatment Plant

**Conventional Treatment Plant**

**Notes:**
Conventional treatment plants have the potential to produce and  recycle a number of residual streams, such as spent filter backwash (regulated), thickener supernatant (regulated), liquids from dewatering processes (regulated), or filter-to-waste(unregulated).

## Direct Filtration

**Direct Filtration**

**Notes:**
Direct filtration plants have the potential to produce and recycle spent filter backwash (regulated) or filter-to-waste(unregulated).  
If spent filter backwash is not treated prior to recycle, solids loading on to the filters will increase over time because there is no way for solids to be removed from the treatment train.  Therefore, spent filter backwash should receive treatment prior to being returned to the main treatment train.

## What is Filter Backwash Water?

- Resulting water pushed back through the filter in the cleaning process
- Filter backwashing is an integral part of treatment plant operation

**Notes:**
Filters must be routinely backwashed to maintain proper treatment capability of the filter.  The frequency of backwashing and backwash method will vary from plant to plant.  The backwash process fluidizes the filter media and removes particles that have been trapped within the media.  The spent filter backwash will contain the removed particles.

## What is Thickener Supernatant?What are Liquids from Dewatering Processes?

- Thickener supernatant
- The “clear water” that exits sedimentation basins and clarifiers after particles have been allowed to settle out
- Liquids from dewatering processes
- Dewatering processes remove water from waste solids “sludge” in order to reduce the solids volume to be disposed

**Notes:**
Some systems pull the sludge from the sedimentation basins or clarifiers in the main treatment train and thicken the sludge in another clarifier or similar type unit.  The sludge settles to the bottom of the thickener and the clear liquid (supernatant) that exits the top of thickener can be recycled.  

Some systems dewater their waste solids and sludge to further reduce the volume for disposal by mechanical (filter press, centrifuge, vacuum) or non-mechanical (drying beds, lagoons, monofills) methods.  The liquid that is removed from the solids during the dewatering process can be recycled.

## Key Components

- Submit data to State
- Plant schematic
- Plant and recycle flow rates
- State-approved operating capacity of plant
- Appropriate recycle return location
- Through all processes of a
- 	system’s conventional and
- 	direct filtration treatment
- State-approved alternative
- 	location
- Maintain specific records

**Notes:**
The FBRR consists of three distinct components:
Reporting
Recycle Return Location
Recordkeeping 

## Notify State in Writing §141.76(b)

- Notify State in writing by December 8, 2003, if system recycles
- Notification must include:
- Plant schematic
- Origin of all recycle flows
- Hydraulic conveyance used to transport them
- Location where they are recycled back into the plant
- Flow data
- Typical recycle flow (gpm)
- Highest observed plant flow from previous year (gpm)
- Design flow for treatment plant (gpm)
- State-approved operating capacity

**Notes:**
Reporting
Systems must notify (Recycle Notification) the State about their recycle practices.  The information must include plant schematic, typical recycle flow, highest observed plant flow in the previous year, design flow, and State-approved operating capacity.  States should evaluate this information and make an initial assessment of the recycle practices.  An example Recycle Notification form is available in the FBRR Guidance Manuals.

## Treatment Technique Requirement §141.76(c)

- By June 8, 2004, must return recycle flow through either:
- Processes of conventional or direct filtration system
- Alternative location approved by the State
- If capital improvements are required to modify recycle location, must be completed no later than June 8, 2006

**Notes:**
Recycle return location
The recycle return location must incorporate all conventional treatment processes (coagulation, flocculation, sedimentation, and filtration) or direct filtration processes (coagulation, flocculation, and filtration).  
Some systems may have a recycle location that does not incorporate all treatment processes, but are still able to maintain high finished water quality.  These systems can request that an alternative recycle return location by approved the State.   It is suggested that systems submit this request and supplemental information with the recycle notification since alternative locations must be APPROVED by June 8, 2004.

## Recycle Return Location

**Recycle Return Location**

**Notes:**
This schematic illustrates the allowed recycle return location under the FBRR.  Systems may request an alternative location from the State.

## Example 1

**Example 1**

**Notes:**
An example of a system where FBRR applies since spent filter backwash is recycled.

Recycle return location complies with the rule.

A treatment unit should be provided to remove solids to minimize solids loading to the main treatment train.

## Example 2

**Example 2**

**Notes:**
FBRR would not apply as this is only filter-to-waste recycled (not regulated).
Since solids are typically minimal in filter-to-waste streams, a treatment unit may not be necessary.

## Example 3

**Example 3**

**Notes:**
FBRR applies.  Spent filter backwash and thickener supernatant are recycled.

Return location does not comply with the rule.  System must relocate return location or receive approval from State for alternative return location.

The holding tank in this example will allow solids to settle prior to recycle.

## Recordkeeping by Systems §141.76(d)

- Beginning June 8, 2004, the following info must be on file for review and evaluation by the State
- Copy of recycle notification and information submitted to State
- List of all recycle flows and frequency of return
- Average and maximum
- Backwash flow rate through filters
- Duration of the filter backwash
- 	process (minutes)

**Notes:**
Recordkeeping
Systems must record all recycle flows (regulated and non-regulated) and the frequency at which they are returned (once per day, continuously, intermittently throughout the day, or other frequency).

## Typical filter run length and written summary of how determined (headloss, turbidity, time)
Type of treatment provided for recycle flow
Data on 
Physical dimensions of equalization and/or treatment units
Typical and maximum hydraulic loading rates
Type of treatment chemicals used and average dose and frequency of use
Frequency at which solids are removed from treatment units

- Type of treatment provided for recycle flow
- Data on
- Physical dimensions of equalization and/or treatment units
- Typical and maximum hydraulic loading rates
- Type of treatment chemicals used and average dose and frequency of use
- Frequency at which solids are removed from treatment units

**Recordkeeping by Systems §141.76(d)**

**Notes:**
Recordkeeping (cont.)
Systems must collect and retain all the required information by June 8, 2004, and make this information available to the State during any State site visit, such as a sanitary survey, Comprehensive Performance Evaluation, or other activity. 

The collected information will provide additional information to the State on the system’s recycle practices.  The State will assess all information and identify recycle practices that may be impairing treatment plant performance.  States will want to closely evaluate all collected recycle information if a system is experiencing treatment technique violations for turbidity standards. An example recordkeeping form is available in the FBRR Guidance Manuals.

## Violations and Public Notification

**Violations and Public Notification**

## State Primacy Requirements § 142.12(b)(1)(2)

- June 8, 2003:  Final primacy applications due unless granted extension
- June 8, 2005:  Final primacy revision applications from States with approved extensions must be submitted

## State Special Primacy Requirement § 142.16(i)(1)(i)

- States must have the proper rules and authority to use sanitary surveys, comprehensive performance evaluations (CPEs), other inspections, or other activities to evaluate recycle data maintained by systems and require modifications to recycle practices

**Notes:**
This special primacy requirement can be satisfied by a description of statutes, rules, or other authority the State can use to evaluate recycle data maintained by systems through inspections and activities such as sanitary surveys or CPEs AND require modifications to recycle practices.

## Available FBRR Documents

- Filter Backwash Recycling Rule:  A Rule Summary for Systems
- Fact Sheet:  Filter Backwash Recycling Rule
- Filter Backwash Recycling Rule:  A Quick Reference Guide
- Filter Backwash Recycling Rule Technical Guidance Manual (under development)
- Filter Backwash Recycling Rule Implementation Guidance

**Notes:**
Some materials are still in draft form.
All final materials will be posted to the site listed on the next page.

## For More Information

**www.epa.gov/safewater/filterbackwash.html**
**Safe Drinking Water Hotline 1-800-426-4791**
**	**

**Notes:**
States may wish to add their contact information.