Office of
United States Ground Water and
^1 Environmental Protection Agency Drinking Water

CLASS V UIC STUDY FACT SHEET
FOOD PROCESSING WELLS
What is a food
processing well?
Food processing wells are Class V underground injection (UIC) wells used to dispose of food
preparation-related wastewater and equipment or facility wash down water. These wells are usually
constructed as septic tanks and leachfields, athough some are simply drywells that allow wastewater to
enter the soil untreated.
What types of fluids are
injected into food
processing wells?
Food processing wastewater that may contain high levels of organic substances (e.g., food waste),
cleaning compound residues, and various inert substances.
Do injectate constituents
exceed drinking water
standards at the point of
injection?
No injectate sampling has been performed, so it is difficult to say what (if any) constituents exceed
standards. However, based on observations during site visits and assumptions described in studies of
similar wastewater treatment systems, it appears likely that the concentrations of nitrate, nitrite, total
colifonn, and ammonia may exceed primary drinking water standards or health advisory levels. It is
also possible that the secondary drinking water standards for turbidity and chloride may be exceeded.
What are the
characteristics of the
injection zone of a food
processing well?
Food processing wells typically inject above underground sources of drinking water (USDWs) and into
a variety of different geological formations, terrains, and soils. However, one recently closed food
processing well at a fruit processing facility in Hawaii was injecting directly into a USDW. Site visits
in TN revealed that some food processing facilities inject slaughterhouse wastewater, via septic
systems, into fractured geologic units and karst terrains that apparently had very little top soil.
Are there any
contamination incidents
associated with food
processing wells?
Only one USDW contamination incident has been identified that is clearly linked to a food processing
well. In ME, a lobster processing/holding facility discharged large volumes of seawater into its
combined food processing well and sanitary septic system. As a result, the chloride concentration in a
nearby private drinking water well exceeded the secondary drinking water standard.
Are food processing
wells vulnerable to spills
or illicit discharges?
Food processing wells may be vulnerable to receiving spills that occur at the facility. Some food
processing facilities use strong cleaning compounds to clean or disinfect equipment and, based on
observations from site visits, some facilities may not always be storing these chemicals in storage areas
away from floor drains that are connected to food processing wells.
How many food
processing wells exist in
the United States?
There are at least 741 documented food processing wells and more than 1,468 estimated to exist in the
United States.
Where are food
processing wells located
within the United States?
Of the 741 documented wells, 43 percent are found in ME and NY and 52 percent are found in AL and
WV. The remaining few are found in AK, WI, HI, and a few other states. TN also has a significant
number of food processing wells but the inventory has not been finalized.
How are food processing
wells regulated in states
with the largest number
of this type of well?
Permit by rule: AL, TN, WV, and IA
Individual or general permit. AK, ME, NY, OR, and WI
Varies by county/region: CA
Banned: OR
Where can I obtain
additional information
on food processing wells?
For general information, contact the Safe Drinking Water Hotline, toll-free 800-426-4791. The Safe
Drinking Water Hotline is open Monday through Friday, excluding federal holidays, from 9:00 a.m. to
5:30 p.m. Eastern Standard Time. For technical inquiries, contact Amber Moreen, Underground
Injection Control Program Office of Ground Water and Drinking Water (mail code 4606), EPA, 401
M Street, SW, Washington, D.C., 20460. Phone: 202-260-4891. E-mail: mo re e n. a mb e r Vv c pa. go v. The
complete Class V UIC Study (EPA/816-R-99-014, September 1999), which includes a volume
addressing food processing wells (Volume 6), can be found at
http://www.epa.gov/OGWDW/uic/cl5study.html.

-------