GB Series Great Basin Grease Interceptors

Great BasinTM Grease Interceptors

The Great BasinTM is the world’s best grease interceptor
designed to offer better performance and better pump-out
information. It comes with the only lifetime warranty in the
industry. The first Great BasinTM grease interceptor was installed
in 2006, forging a new category in the world of grease
interceptors. Prior to 2006, there were undersized steel grease
traps inside of the building and oversized concrete grease
interceptors outside of the building. These products offered
little-to-no information in the way of performance. The Great
BasinTM was designed to offer better performance and better
pump-out information along with the only lifetime warranty in the
industry.

Safety Warnings

It is important to follow these safety warnings to prevent
property damage, personal injury, or death:

• Perform frequent interceptor maintenance that includes complete
  removal (pumpout) of all interceptor contents. Schier recommends a
  pumpout cycle of 30 to 90 days to prevent buildup of dangerous H2S
  vapors, maintain sanitary conditions, and ensure the interceptor
  performs as designed.

• All grease interceptors meet the OSHA definition of a confined
  space; they have the potential to contain a hazardous atmosphere,
  and contain material that could engulf an entrant (water, grease,
  and solids). Enter the space only if necessary and follow
  established procedures:

  • Never leave an open grease interceptor accessway
    unattended.

  • Always replace the cover and secure with bolts if equipped.
    Failure to do so risks pedestrian injury or death. Replace damaged
    or missing cover bolts promptly.

Special Precautions for Installation

It is important to follow these precautions during installation
to avoid voiding your warranty:

• Do not air test unit or riser system.

• Do not install the unit in any manner except as described in
  the installation instructions.

• Read all instructions prior to installation. Interceptor is
  intended to be installed by a licensed plumber in conformance with
  all local codes.

OWNER’S MANUAL
Great BasinTM Grease Interceptors
GBOM-0123

The world’s best grease interceptor
Please use the information in this manual to make the most of your Great BasinTM. We are confident that you will be happy with your investment and we truly value your business. Please contact Schier anytime with questions or feedback.
Table of Contents
Safety Warnings and Special Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 Why Grease Interceptors Are Necessary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Great BasinTM Series Identification and Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8 Grease Interceptor Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Suggested Maintenance Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Calculating Pump-Out Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Core Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Kitchen Best Management Practices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Maintenance Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
History
The very first Great BasinTM grease interceptor was installed in 2006, forging a new category in the world of grease interceptors. Prior to 2006, it was undersized steel grease traps inside of the building and oversized concrete grease interceptors outside of the building. These products offered little-to- no information in the way of performance. Worse, due to inferior materials and the corrosiveness of commercial kitchen wastewater, all of these units are guaranteed to fail.
The Great BasinTM was designed to offer better performance and better pump-out information along with the only lifetime warranty in the industry. With thousands of installations from San Francisco to Singapore, Schier has a growing fleet of corporate account specifications, installations at over 15 professional sports stadiums, thousands of restaurants, schools, corporate campuses, One World Trade Center and (we’ve been told) the White House.

1

Great BasinTM Owners Manual schierproducts.com 913-951-3300

SAFETY WARNINGS
For all Schier Grease Interceptor Maintenance – Failure to heed these warnings may result in property damage, personal injury or death.

HYDROGEN SULFIDE (H2S) GAS Large grease interceptors with low flows are conducive to creating septic conditions that can generate H2S gases and the associated “rotten egg” odor. Produced naturally from decaying organic matter, H2S vapors are noxious, highly toxic, flammable and potentially corrosive to metal and concrete. If inhaled, these vapors can be lethal, or cause you to lose consciousness and possibly fall into the grease interceptor and drown.
Newer Schier grease interceptors feature a Safety Star® access restrictor in the accessway to help prevent accidental falls. Do not remove the Safety Star® from the accessway unless absolutely necessary. Never cut the tether that permanently attaches the Safety Star® to the accessway. Replace worn or damaged tethers promptly.
Perform frequent interceptor maintenance that includes complete removal (pumpout) of all interceptor conents. Schier recommends a pumpout cycle of 30 to 90 days. Doing so will prevent buildup of dangerous H2S vapors, maintain sanitary conditions and ensure the interceptor performs as designed.

CONFINED SPACE All grease interceptors meet the OSHA definition of a confined space; they have the potential to contain a hazardous atmosphere, and contain material that could engulf an entrant (water, grease and solids). Enter the space only if necessary and follow established procedures:
· Test (monitor) the air in the space from the outside before entering.
· Test (monitor) the air in the space continuously during work operation.
· Determine if entry permit is required. · Ventilate area continuously to remove accumulated
hydrogen sulfide. · Make sure that rescue procedures, personnel, and equipment
are in place. · Maintain contact with trained attendant.
Never leave an open grease interceptor accessway unattended. Always replace the cover and secure with bolts if equipped. Failure to do so risks pedestrian injury or death. Replace damaged or missing cover bolts promptly.

SPECIAL PRECAUTIONS
For Schier Grease Interceptor Installations – Failure to follow this guidance voids your warranty

DO NOT AIR TEST UNIT OR RISER SYSTEM! Doing so may result in property damage, personal injury or death.

Do not install the unit in any manner except as described in the installation instructions.

Installation Instructions
Installation instructions and additional components are included with the interceptor. Read all instructions prior to installation. Interceptor is intended to be installed by a licensed plumber in conformance with all local codes.

Install interceptor as close as possible to fixtures being served

Provide clearance above unit for routine maintenance. See p. 10

Maintenance Clearance

ODOR ALERT!
Interceptor is not a sewer gas trap. All upstream fixtures must be trapped
ODOR ALERT!
Do not install air gap on outlet side of interceptor.

Great BasinTM Owners Manual schierproducts.com 913-951-3300

2

SPECIAL PRECAUTIONS
For Schier Grease Interceptor Installations – Failure to follow this guidance voids your warranty

High Temperature Kitchen Water
cold water supply line high temperature effluent ( > 150º F) approved backflow
prevention assembly DTV (drain water tempering valve)

Fully Support Base of Unit
Install unit on solid, level surface in contact with the entire footprint of unit base
Support Inlet and Outlet Piping
For above grade installations ensure heavy inlet and outlet piping (such as cast iron or long runs) is properly supported or suspended during the entire installation process to prevent connection failure or damage to bulkhead fittings.

pipe supports

Suspended Installations
Design trapeze to support the wet weight of the unit. Do not partially support unit or suspend unit using metal U-channel to create a trapeze.

concrete floor

directly connected

indirectly connected

If water is entering the interceptor at excessive temperature (over 150º F), a drain water tempering valve (DTV) and approved backflow prevention assembly must be installed. Most state and local plumbing codes prohibit water above 150º F being discharged into the sanitary sewer. Water above 150º F will weaken or deform PVC Schedule 40 pipe, poly drainage fixtures like interceptors and erode the coating of cast iron (leading to eventual failure).

DO NOT USE CAST IRON COVERS IN ABOVE GRADE OR INDOOR INSTALLATIONS
Use composite cover C24BC for above grade installations

When Installing Interceptor Inside
If your dishwashing sink(s)

Fernco or similar rubber flow restriction end cap

discharges into a floor

drain/sink (drain), you must

regulate the flow into the drain

to avoid an overflow of water

onto the kitchen floor. This can

be done by installing a valve or

flow restriction cap on the sink

piping that discharges into the drain. See drawing for guidance. For detailed

guidance on indirect connections, go to:

webtools.schierproducts.com/Technical_Data/Indirect_Connections.pdf

Above Grade Installation Support
The wet weight of the interceptor combined with high temperature kitchen water creates the potential for tank deformation when installed above grade. Model GB-500 installed above grade must be installed with Above Grade Support Kit model AGS2 to maintain structural integrity.
Secure Cover Adapters
Cover adapters must be secured to newer model base units in above grade installations with increased head pressure conditions. Use cover adapter tie- down kit model ATD1. See your specific Specification/Submittal and Installation guide to determine necessity.

AGS2

3

Great BasinTM Owners Manual schierproducts.com 913-951-3300

SPECIAL PRECAUTIONS
For Schier Grease Interceptor Installations – Failure to follow this guidance voids your warranty

High Water

Table Installations
Interceptors and risers are not

max water table height for direct burial

designed to withstand water table

height in excess of the top of the unit

when buried (see figure). If it is possible

for this to occur, install the interceptor

and risers in a water-tight concrete vault

or backfill with concrete or flowable fill

(wet concrete and flowable backfill should be poured in stages to avoid crushing the interceptor). At risk areas

GB-250 with model AK1 anchor kit shown

include but are not limited to tidal surge

areas, floodplains and areas that receive storm water. Great BasinTM models that are

direct buried in high water table scenarios must be installed with the anchor kit

reccommended in their specific Specification/

Submittal and Installation Guide.

Hydrostatic/ Pressure Slabs
When installed under a hydrostatic slab (slab designed to withstand upward lift, usually caused by hydrostatic pressure) interceptor must be enclosed in a watertight concrete vault.

concrete slab subject to hydrostatic pressure
watertight concrete vault

DO NOT COMPACT BACKFILL MECHANICALLY
Compact by hand only

Below Grade Installation Slab Requirements
A concrete slab to finished grade with rebar is required when installing interceptor below grade.

Rebar

4″ min. slab

Rebar

8″ min. slab

Pedestrian Traffic or Greenspace Areas
Installations with Risers 2 FCR1 Risers Max
25″

Vehicular Traffic Areas
3 FCR2 Risers Max 94″

Max Water Level Risers are not designed
to retain water

Flush-to-Grade Burials
Flush-to-Grade buried installations (without a riser) are not recommended for heavy foot traffic areas without the use of an internal gusset support kit SGK2 (for GB2) or SGK3 (for GB3).

Corrugated Riser Pipe

CA2

Requirements

Riser adapter model CA2 must be used when installing interceptors using 24″ diameter corrugated pipe as a riser. This will adequately embed the cover adapter in the concrete slab, preventing cover/cover adapture failure under traffic rated loads.

6 – 94″

Great BasinTM Owners Manual schierproducts.com 913-951-3300

4

Why Grease Interceptors Are Necessary
Grease interceptors, sometimes called grease traps or grease pits, are required in most food service establishments. The primary function is to separate and store the fats, oils and grease that are washed down the drain during food prep and dishwashing. Without grease interceptors, fats, oils and grease will build up on the walls of drainage piping, ultimately causing a blockage. This can lead to an immediate back-up in your kitchen, or worse, the city’s wastewater collection system. When a blockage happens in the city’s system, it can lead to a Sanitary Sewer Overflow (SSO), which results in raw sewage flooding out of manhole covers spreading dangerous bacteria into streets and walkways. SSOs are a leading cause of fresh water contamination and can be deadly for fish, plankton and other aquatic life. By properly maintaining your Great BasinTM, you are doing your part to protect the environment.

Inside of pipe showing effects of an improperly maintained grease interceptor
5

Inside of pipe of a properly maintained grease interceptor
Great BasinTM Owners Manual schierproducts.com 913-951-3300

Great BasinTM Identification and Specifications
Since its introduction, the Great BasinTM series has led the industry in hydromechanical interceptor design and performance. The series has evolved during that time, resulting in a variety of units with similar or identical model numbers but different shell designs and certified grease capacities. This section is provided to help you determine which interceptor you have installed. Locate the product ID label located on the interceptor and make note of the model, 9-digit part number and the serial number. If buried, the label will be on the underside of the cover or the inner wall of the cover adapter. Contact customer service if unsure what model you have.

GB-15

Years Produced: 2011 – 2018 Identification: Single 16″ cover.
Flow Rate/Grease Capacity: 15 GPM / 74 lbs. (10.1 gal.)
Liquid Capacity: 16 gal. Solids Capacity: 3.9 gal.

GB1

Years Produced: 2017 – present Identification: Single 21″ cover.
Flow Rates/Grease Capacities: 20 GPM / 70 lbs. (9.6 gal.) 25 GPM / 64 lbs. (8.9 gal.)
Liquid Capacity: 10 gal. Solids Capacity: 1.3 gal.

GB-20

Years Produced: 2011 – 2018 Identification: Single 16″ cover.
Flow Rate/Grease Capacity: 20 GPM / 109 lbs. (14.9 gal.)
Liquid Capacity: 22 gal. Solids Capacity: 6.4 gal.

GB2

Years Produced: 2017 – present Identification: Single 21″ cover.
Flow Rates/Grease Capacities: 35 GPM / 130 lbs. (17.9 gal.) 50 GPM / 127 lbs. (17.5 gal.)
Liquid Capacity: 20 gal. Solids Capacity: 1.8 gal.

GB-25

Years Produced: 2011 – 2018 Identification: Single 16″ cover.
Flow Rate/Grease Capacity: 25 GPM / 75 lbs. (10.3 gal.)
Liquid Capacity: 22 gal. Solids Capacity: 6.4 gal.

GB2-2 (99%)

Years Produced: 2019 – present Identification: Two 21″ covers (2 tanks in series).
Flow Rates/Grease Capacities: 35 GPM / 180 lbs. (24.7 gal.)
Liquid Capacity: 40 gal. Solids Capacity: 3.6 gal.

GB-35

Years Produced: 2011 – 2018 Identification: Single 16″ cover.
Flow Rate/Grease Capacity: 35 GPM / 142 lbs. (19.5 gal.)
Liquid Capacity: 35 gal. Solids Capacity: 9.5 gal.

GB3

Years Produced: 2017 – present Identification: Single 21″ cover.
Flow Rates/Grease Capacities: 50 GPM / 272 lbs. (37.4 gal.) 75 GPM / 175 lbs. (24.1 gal.)
Liquid Capacity: 40 gal. Solids Capacity: 1.9 gal.

Great BasinTM Owners Manual schierproducts.com 913-951-3300

6

Great BasinTM Identification and Specifications

GB-50
Gen 1
Gen 2
GB-75
Gen 1
Gen 2
Gen 3

Years Produced: 2011 – 2019
Identification: 24″ cover, no Safety Star®
Flow Rate/Grease Capacity: 50 GPM / 249 lbs. (34 gal.)
Liquid Capacity: 52 gal. Solids Capacity: 12.5 gal.

GB-75-2-Series (99%)
Years Produced: 2019 – 2020 Identification: 24″ covers, no Safety Star®, black diffusers, two units in series
Flow Rate/Grease Capacity: 75 GPM / 861 lbs. (118 gal.)
Liquid Capacity: 250 gal. Solids Capacity: 38.4 gal.

Years Produced: 2019 – present Identification: 24″ cover with Safety Star® access restrictor
Flow Rate/Grease Capacities: 50 GPM / 439 lbs. (60 gal.) 75 GPM / 287 lbs. (39 gal.)
Liquid Capacity: 65 gal. Solids Capacity: 13 gal.

GB-75-B (99%)
Years Produced: 2020 – present Identification: 24″ cover with Safety Star® access restrictor.
Flow Rate/Grease Capacity: 50 GPM / 623 lbs. (85 gal.)
Liquid Capacity: 125 gal. Solids Capacity: 0 gal.

Years Produced: 2011 – 2018
Identification: 24″ cover, no Safety Star®, black diffusers
Flow Rate/Grease Capacity: 75 GPM / 616 lbs. (84 gal.)
Liquid Capacity: 125 gal.
Solids Capacity: 19.2 gal.

GB-250
Gen 1

Years Produced: 2018 – 2020
Identification: 24″ covers, no Safety Star®, white or black round diffusers
Flow Rate/Grease Capacity: 75 GPM / 653 lbs. (89 gal.)
Liquid Capacity: 125 gal.
Solids Capacity: 19.2 gal.

Gen 2

Years Produced: 2020 – present
Identification: 24″ cover with Safety Star® access restrictor.
Flow Rate/Grease Capacity: 75 GPM / 861 lbs. (118 gal.)
Liquid Capacity: 125 gal.
Solids Capacity: 31 gal.

Gen 3

Years Produced: 2008 – 2018 Identification: 24″ covers, no Safety Star®, black diffusers Flow Rate/Grease Capacity:
100 GPM / 1,076 lbs. (147 gal.) Liquid Capacity: 275 gal. Solids Capacity: 105 gal.
Years Produced: 2018 – 2020 Identification: 24″ covers, no Safety Star®, white or black round diffusers Flow Rates/Grease Capacities:
100 GPM / 1,751 lbs. (240 gal.) 200 GPM / 1,196 lbs. (164 gal.) Liquid Capacity: 275 gal. Solids Capacity: 21 gal.
Years Produced: 2020 – present Identification: 24″ covers with Safety Star® access restrictors Flow Rates/Grease Capacities:
100 GPM / 1,895 lbs. (260 gal.) 200 GPM / 1,196 lbs. (164 gal.) Liquid Capacity: 275 gal. Solids Capacity: 69 gal.

7

Great BasinTM Owners Manual schierproducts.com 913-951-3300

Great BasinTM Identification and Specifications

GB-250-2 Series (99%)
Years Produced: 2019 – present Identification: 24″ covers, no Safety Star®, white or black round diffusers, 2 units in series
Flow Rate/Grease Capacity: 100GPM / 2,593 lbs. (355 gal.)
Liquid Capacity: 550 gal. Solids Capacity: 42 gal.

GB-1000 (99%)

Gen 1

Years Produced: 2018 – present
Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 6,237 lbs. (854 gal.)
Liquid Capacity: 1,010 gal.
Solids Capacity: 103 gal.

GB-250-B (99%)
Years Produced: 2020 – present Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 75 GPM / 1,817 lbs. (249 gal.)
Liquid Capacity: 277 gal. Solids Capacity: 103 gal.

GB-500

Years Produced: 2018 – present
Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 3,048 lbs. (418 gal.)
Liquid Capacity: 510 gal.
Solids Capacity: 128 gal.

GB-500-B (99%)
Years Produced: 2019 – present Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 2,817 lbs. (386 gal.)
Liquid Capacity: 510 gal. Solids Capacity: 102 gal.

GB-1000
Gen 1

Years Produced: 2018 – present
Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 6,547 lbs. (897 gal.)
Liquid Capacity: 1,010 gal.
Solids Capacity: 103 gal.

Gen 2
GB-1000-B

Years Produced: 2021 – present Identification: 24″ covers with Safety Star® access restrictors Flow Rate/Grease Capacity:
100 GPM / 5,272 lbs. (687 gal.) 200 GPM / 3,127 lbs (369 gal.) Liquid Capacity: 1,000 gal. Solids Capacity: 211 gal.
Years Produced: 2020 – present Identification: 24″ covers with Safety Star® access restrictors Flow Rate/Grease Capacity:
200 GPM / 3,939 lbs. (540 gal.) Liquid Capacity: 1,010 gal. Solids Capacity: 103 gal.

GB-1000-B (99%)
Years Produced: 2020 – present Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 200 GPM / 3,681 lbs. (504 gal.)
Liquid Capacity: 1,010 gal. Solids Capacity: 103 gal.

GB-1500

Years Produced: 2022 – present Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 10,061 lbs. (1,207 gal.) 200 GPM / 9,446 lbs (1,133 gal.)
Liquid Capacity: 1,588 gal Solids Capacity: 318 gal.

Gen 2

Years Produced: 2021 – present Identification: 24″ covers with Safety Star® access restrictors
Flow Rate/Grease Capacity: 100 GPM / 5,495 lbs. (716 gal.) 200 GPM / 4,959 lbs. (647 gal.)
Liquid Capacity: 1,000 gal. Solids Capacity: 211 gal.

Great BasinTM Owners Manual schierproducts.com 913-951-3300

8

Grease Interceptor Components
Generic side view diagram of a typical Great BasinTM grease interceptor.

1

14

2

3

4

15

5

6

16

7

6

8

17

9

10

10

11

18

12

13

19

FLOW

1 Cover
2 Cover Adapter Larger models (with 24″ diameter covers) will have a cover adapter.
3 Riser
4 Flow Control Cartridge A red cartridge may be found here on models produced after 2018. If white, the cartridge is for preventing unit swamping and does not regulate flow.
5 Flow Control Plate A snap-in red plate that may be found on the snout of the inlet diffuser on any model produced from 2014 until 2019.
6 Saddle Adapter Early GB1, GB2 and GB3 models feature this adapter which allows for easy insertion and removal of the inlet and outlet diffusers.
7 Flow Control Plate A snap-in white plate that may be found on the snout of the saddle adapter on indoor models produced from 2014 until 2019.
8 6″ Flow Control Plate A screw-on white plate may be found here on models with 6″ connections.

9 Inlet Bulkhead Connection
10 Diffuser Locking Collar Used to secure the diffusers (or saddle adapters) to the bulkhead connections.
11 Flow Control Aperture A permanent hole in the inlet diffuser snout used with all models produced prior to 2014.
12 Inlet Diffuser
13 Inlet Diffuser Foot Later models may have a foot attached to the inlet diffuser. If removed, ensure it is replaced and oriented so that the foot directs flow to the inlet endwall.
14 Safety Star® Access restrictor for newer models with 24″ diameter covers.
15 Air Relief/Visual Access
16 Optional Outlet Bulkhead Connection
17 Outlet Bulkhead Connection
18 Outlet Diffuser
19 Outlet Diffuser Foot Later models may have a foot attached to the outlet diffuser. If removed, ensure it is replaced and oriented so that the foot directs flow to the outlet endwall.

9

Great BasinTM Owners Manual schierproducts.com 913-951-3300

Routine Maintenance Procedure

1. Remove cover(s). Do not remove Safety Star® access restrictor (if present) for routine maintenance.
2. Remove all interceptor contents including grease, sediment and wastewater. For most thorough cleaning contact a professional pumper contractor.

3. Run sinks to fill unit(s) with cold water.
4. Inspect cover gasket for wear and tear. Replace cover(s). Avoid using power tools to tighten bolted covers as it may strip the heads.
5. Dispose of grease per local code.

NOTE: It is not necessary to remove the diffusers during routine maintenance unless there is a backup or drain lines require jetting. To remove most inlet and outlet diffusers, hand loosen the green locking collars. If interceptor is equipped with saddle adapters, pull the diffusers straight up to remove. With diffusers removed, clean the drain lines, diffusers and air relief thoroughly of all debris as needed.

Routine Maintenance Clearance Heights

The following are the minimum clearance heights required above the interceptor cover to be able to access and remove any internal interceptor components. These clearance heights apply to any generation of interceptor. Do not install permanent fixtures (i.e. plumbing) within these zones.

model(s)

GB1, GB2, GB3

minimum clearance height (inches)

5.5

GB-15, GB-20, GB-25 8

GB-35, GB-50 12

GB-75, GB-250, GB-500
16

GB-1000 GB-1500
72

Great BasinTM Owners Manual schierproducts.com 913-951-3300

10

Calculating Pump-Out Frequency
All grease interceptors have a maximum grease holding capacity. Once that maximum capacity is exceeded, fats, oils and grease (FOG) will bypass to the collection system, creating the potential for blockages. It’s critical to determine an accurate pump-out schedule that ensures the interceptor gets pumped out only as often as necessary, but before it reaches its maximum rated capacity. Your Great BasinTM grease interceptor should have been sized according to the Grease Production SizingTM (GPS) and assigned a pump-out schedule prior to installation. If it wasn’t, or if circumstances have changed, use the following formula to get your pump-out schedule back on track.

Grease Capacity
(See pages 6-8)

Meals Per Day

Grease Production Values

(see

below)

Pumpout Frequency in Days

Foodservice Establishment (FSE) Grease Production Values

category low medium high

grease production values 0.005 lbs / meal (no flatware) 0.0065 lbs / meal (with flatware) 0.025 lbs / meal (no flatware) 0.0325 lbs / meal(with flatware) 0.035 lbs / meal (no flatware) 0.0455 lbs / meal (with flatware)

description / examples
serves food prepared offsite or food that requires minimal preparation and/or warming; sandwich shop, convenience store (no kitchen), hotel breakfast bar, frozen yogurt, coffee shop, take & bake pizza, bar (limited food service), cafeteria (no prep), grocery meat department, sushi (no grill)
serves foods from a limited menu and/or with a limited amount of onsite preparation; pizza, ice cream parlor, fast food hamburger (pre-cooked), caterer, Greek, Japanese, Vietnamese (Pho), grocery store (no fryer), cafeteria (limited prep), low category restaurants w/ fryer
serves a full menu of food prepared onsite; American traditional, hamburger (with grill), BBQ, Mexican, Italian, steak/ seafood house, hibachi, buffet, fast food fried chicken, bakery/donut shop (w/fryer), Chinese, Indian, grocery store (w/ fryer), cafeteria (full prep), medium category restaurants w/ fryer

Please note that GPS may not satisfy local jurisdictional requirements for installation approval and should always be verified prior to selection. The easiest way to verify sizing for any project is to use our Grease MonkeyTM sizing tool ( https:// greasemonkeysizing.com/ ). When scheduling pump-outs, Schier recommends a pumping frequency between 30 and 90 days. Your calculations should be updated if number of meals per day, operating days per week or the menu types (more greasy or less greasy) change.

11

Great BasinTM Owners Manual schierproducts.com 913-951-3300

Core Samples
If you prefer not to rely solely on the GPSM to dictate pre-scheduled monthly pumpouts, you can take a more commanding role in dictating pump-out frequency with some simple tools and regular inspections. To do this you will need a core sampler. Popular brand names include DipStick Pro and Sludge Judge .
Once you have your core sampler, it can be outfitted with some simple labeling (via high adhesive tape or permanent marker) to indicate your pump-out levels (see below). Contact customer service if unsure what model you have.
NOTE: Series Installations
When installed in series, initially the first unit will fill up with grease while passing some grease to subsequent unit(s). As the grease layer in the first unit grows, more grease will pass to subsequent units. When it reaches maximum capacity, the first unit will pass all grease to subsequent unit(s). Core samples should be taken from the final tank in the series and pump-out scheduling should be conducted when it is near full capacity.

GB-250 (100 GPM) Core Sample at Full Capacity

22″ 31″
column

grease

water

8″

solids

Core Sample Measurements at Full Capacity*

Model
GB1 GB1 GB2 GB2 GB2-2 (99%) GB3 GB3 GB-15 GB-20 GB-25 GB-35 GB-50 (Gen 1) GB-50 (Gen 2) GB-50 (Gen 2) GB-75 (Gen 1) GB-75 (Gen 2) GB-75 (Gen 3) GB-75-2-Series (Gen 2, 99%) GB-75-B (Gen 3, 99%) GB-250 (Gen 1) GB-250 (Gen 2) GB-250 (Gen 3) GB-250 (Gen 2 & 3) GB-250-2 Series (Gen 2, 99%) GB-250-B (Gen 3, 99%) GB-500 GB-500-B (99%) GB-1000 (Gen 1) GB-1000 (Gen 2) GB-1000 (Gen 2) GB-1000 (Gen 1, 99%) GB-1000 (Gen 2, 99%) GB-1000 (Gen 2, 99%) GB-1000-B (99%) GB-1500

ASME Certification Type
C C C C C C C C C C C C D D C C D C D C C D C C D C D C D D C D D D D

Flow Rate (GPM)
20 25 35 50 35 50 75 15 20 25 35 50 50 75 75 75 75 75 50 100 100 100 200 100 75 100 100 100 100 200 100 100 200 200 100

Maximum Grease
Capacity (lbs)
70 64 130 127 180 272 175 74 109 75 142 249 439 287 616 653 861 861 623 1,076 1,751 1,895 1,196 2,593 1,817 3,048 2,817 6,547 5,495 4,959 6,237 5,272 3,127 3,681 10,061

Total Liquid Height (In)
5.25 5.25
7 7 7 13.75 13.75 9 10 10 14 16 17.5 16.25 24 24 24 24 24 36 36 29.5 36 36 29.5 35 35 53 53 53 53 53 53 53 57

Maximum Grease
Height (In)
5 4.6 6.25 6.1 2.6 12.8 8.25 5 6.6 4.4 6.2 9.1 13 9.5 16.6 17.3 17.5 5.5 16.5 18.8 30 22 20 14.5 22.75 25.8 30.5 42 42 34.5 39.75 35.5 21.5 42 47

Maximum Grease % of
Volume
95% 88% 89% 87% 62% 93% 60% 63% 68% 47% 56% 66% 75% 58% 68% 71% 75% 75% 68% 54% 87% 75% 59% 64.5% 89% 82% 76% 89% 74% 67% 85% 71% 42% 50% 80%

Maximum Solids
Height (In)
0.75 0.75 0.75 0.75
0 0.75 0.75
2 2 2 2.6 3.3 3.25 3.25 1.5 1.5 6.75 1.5 6 12.8 2.6 8.5 2.6 0 8.5 10.9 0 4.8 21 21 4.8 21 21 0 16

• Please note that as the grease layer inside of a grease interceptor accumulates it displaces the water below it downward. Much like an iceberg this grease layer will partially float above the static water line while the majority of it rests below it. As a result, the static water line of grease interceptor when at total grease capacity is slightly greater than the standard published static water line.

Great BasinTM Owners Manual schierproducts.com 913-951-3300

12

Kitchen Best Management Practices
The following kitchen best management practices (BMPs) will help reduce the cost to clean and maintain your grease interceptor and keep your facility in good standing with local pretreatment authorities.

1

2

3

Use debris screens in all floor and sink drains. Regularly empty screens into trash.

Minimize use of food waste disposals Dry-wipe food waste from dishes

to improve interceptor storage and before washing and clean grease

reduce maintenance costs.

spills with disposable materials.

4

5

6

NEVER pour oil, fry oil, or melted lard or butter down drain line. Dispose these oils in appropriate container.

NEVER put chemicals for reducing grease into the drain system. The temporarily dissolved grease will bypass the interceptor and harden in downstream piping.

Implement BMP training program for kitchen staff.

7

8

9

Observe pumper contractor work to ensure interceptor is fully pumped out, properly cleaned and in good condition.

Make sure to run sinks to refill unit with cold water after pump-out.

Keep maintenance log detailing pump-outs, repairs and condition of interceptor.

13

Great BasinTM Owners Manual schierproducts.com 913-951-3300

Maintenance Log

Date

Action (Inspection/ pump-out)

Grease Solids Level Level (inches) (inches)

Notes

CONTACT INFORMATION Pumper Contractor Sewer and Drain Contractor Local Authority Having Jurisdiction

Grease Permit #

Great BasinTM Owners Manual schierproducts.com 913-951-3300

14

References

• Grease interceptor sizing. Made easy. | Grease Monkey
• Schier Products | Manufacturing America's Grease Interceptor

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>