Fluoride Receiving Safety

Metropolitan Water District of Salt Lake and SandyMark Sarvela

5 ½ years Metro Plant Manager, System Operator 17 years

Washington StateGO SEAHAWKS!

WHAT IS FLUORIDE?

There are three fluoride compounds used for drinking water fluoridation:1. Fluorosilicic Acid2. Sodium Fluoride3. Sodium Fluorosilicate

Most common in water treatment is Fluorosilicic AcidIt is a water based solution which may also be referred to as hydrofluorosilicate, FSA, or HFS.

Proper Chemical Handling and Operator Safety is Critical!

Fluorosilicic Acid is delivered and added to a water supply in a liquid

Sodium Fluoride and Sodium Fluorosilicate are delivered as dry chemical and then dissolved in water prior to being added to the water supply.

A survey of Oregon and Washington water treatment plants using fluoride found that Fluorosilicic Acid is used at plants with flow rates greater than 40 MGD. A simple design and minimal chemical handling are the primary reasons FSA is most commonly selected by larger utilities.

Before an Operator is to be involved with receiving a delivery of Fluorosilicic acid they must adhere to the following:

1. Understand the MSDS for Fluorosilicic Acid.

2. Understand and follow the SOP.

3. Know the location and condition of the offload eyewash station.

4. Treat all chemicals with caution and respect.

5. Complete training with senior operators before attempting to offload alone.

6. Bulk tank over flow level is (10 ft on Scada) or (11 ft actual).

BLOCK ROADWAY WITH CONES DURING CHEMICAL OFFLOADFluoride Offload at Acid Sump

BUCKETS OF LIME SLURRY FOR NEUTRALIZING

Fluoride Off Load Area

Cam loc fittingAcid Receiving Sump

Double walled containment underground

Locked butterfly Valve

Glued Fittings

Bucket Strainer

FLUORIDE BUILDINGVentilation draw ports

Security Camera

Alarm Strobe

Sump access door

FLUORIDE BUILDING ENTRANCE

ACID RESISTANT COVERALL AND OTHER APPROPRIATE PPE

FLUORIDE FEED PUMPS

Pressure Sensor

Overflow / Vapor Barrier

Containment Sump

Access Door

Sump Pump Discharge Tube

Electrical Outlet

RINSE BUCKETS AT EXIT

Cleanup and HygieneRinse gloves and boots with lime slurry to neutralize

Hose down offload area. Hose down all PPE.

Remove PPE and properly store in locker area or designated area.

Wash hands and face thoroughly. Take a shower if available.

Comments or Questions?

Sources:United States Public Health Service. Review of Fluoride: Benefits and Risks. 1991 www.health.gov/environment/Review/Fluoride

Environmental Protection Agency. Questions and Answers on Fluoride. 2011 http://water.epa.gov/lawsregs/rulesregs

Centers for Disease Control and Prevention. Community Water Fluoridation: Questions and Answers. 2012www.cdc.gov/fluoridation/fact_sheets/cwf_qa.htm

MWDSLS SOP Receiving Fluorosilicic Acid at LCWTP