Presented by:Mark LovittUtilities Department/Pretreatment DivisionTown of Cary, N.C.

Fats Oils and Grease Sampling Presentation

Grease Interceptor Sampling

Nationally and statewide: More focus on proper grease interceptor cleaning and service frequency rather than sampling to judge compliance

Sampling interceptors is a tool: Helps to measure performance and efficiency of the grease interceptor

Useful information for chronic problem areas

Why Sample a Grease Separation Device?

Grab sample: Only collection method recognized for compliance determination by EPA

Collection – Typically a wide mouth 1000 ml glass container is used, depending on the lab used: dip and take method; Not recommended to transfer sample to another container

Sample Collection

· Grab sample · 1000 ml Wide Mouth Glass Container· Teflon lined Cap· Preserved with H2SO4 or HCl to <2.0 std. units· Refrigerate 6.0C

· Maximum hold time 28 days

EPA Manual for Industrial User Inspection And Sampling Manual for POTW’s, April 1994

FOG Sample Collection

1000 ml Glass Sample Container Sulfuric or Hydrochloric Acids (Preservation) pH Meter Thermometer pH Test Strips Chain of Custody/Labels PPE (Personal Protective Equipment) Cooler with Wet Ice

TOOLS OF THE TRADE

TOOLS OF THE TRADE

T Transferring devices

Sa Sample pole with bottle

Solids and Grease Measurement

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Considerations When SamplingIs there a sample point located on grease interceptor?

Considerations When SamplingWhen grease interceptor is hydraulically loaded

Ware being washed? Just using clean water?

Considerations When SamplingCan a Sample Be Collected Properly?

What’s the Goal: FSE Compliance You need the Customer’s Cooperation Coordinate w/FSE to sample when

dishes/ware can be washed

Considerations When SamplingCustomer Service

Sample CollectionHydraulic Jump

Grab Sample Jar Method 1.

Sample Vault with Hydraulic Jump Use where sewer elevation permits

Preferred sampling point and procedure

Connected to greaseinterceptors outlet

Outlet – Discharging tosanitary sewer

Hydraulic Jump

Concrete fill and slopedtoward outlet for completedrainage.

Minimum 6”

Outlet pipe diameter shall be ata minimum equal to or greaterthan inlet pipe diameter

Minimum 4”

HYDRAULIC JUMP SAMPLE VAULT

Hydraulic Jump Sample Vault

Sample CollectionSample Vault-Open Invert

Grab Sample Jar Method 2.Sampling Vault Illustration

2nd most preferred sample point and procedure

8 – 10 “

50% totalwater depth

½ pipe diameter

Sanitary Tee

8 – 10 “Pipe cutout

Concrete fill on both sides ofpipe cutout and sloped tochannel water into pipe.

Flow

“dam” rod & flow-blocking plate

Flow direction

Sample collection jar

Sample CollectionSanitary Tee

Grab Sample Jar Method 3.Sanitary Tee Sample Collection Illustration

Existing interceptor, where sample vault cannot be installed3rd most preferred sample point and procedure

4 – 6”Sanitary tee

Grease Interceptor Wall

Flow

GlassSample Jar

1000 ml

Sample Jar attached tosampling rod

Lower Sample Jar intoSanitary tee and belowthe flowing water levelto obtain sample

Interior Exterior

Plunge Sampler IllustrationSmall interceptors and sanitary tee’s

Vent

Grease Interceptor

Outlet

Flow

Plunge Sampler

Sample Port

Grease Interceptor

Sample Port

Stainless Steel

Rubber Bulb

Discharge to sanitary sewer

Flow

Vent

Bulb Sample MethodSmall Grease Separation Devices

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Pizza Grill Cafeteria Pasta Pizza Bakery Full service menu

Steakhouse

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Sample Site

Method 413 Vs. Method 1664

Method 1664

Method 413

Establishing A Limit

Summary of FOG Sampling : Use sampling of grease interceptors as a

tool of a good FOG Inspection program not the only tool.

FOG Ordinance- Will you use an enforcement limit or action level.

Educate your FSE’s and help them stay in compliance.

In Conclusion

Closing Thoughts and Comments !

Contact Info

Mark LovittUtility Pretreatment Technician ITown of Cary, N.C.mark.lovitt@townofcary.orgPhone: 919-270-6425