Small Water Systems
& Wells
in Los Angeles County

Non-Production Wells and Exploratory Holes

Monitoring Wells

Monitoring wells are constructed to observe conditions at defined or required locations. Monitoring well locations are selected based on known or expected hydrologic, geologic, and water quality conditions and the location of pollutant or contaminant sources. Monitoring wells frequently need to be located close to or within areas of pollution or contamination.

Cathodic Protection Well

Cathodic protection well is any artificial excavation in excess of 50 feet constructed by any method for the purpose of installing equipment or facilities for the protection electrically of metallic equipment in contact with the ground, commonly referred to as cathodic protection.

Geothermal Heat Exchange Well

A geothermal heat exchange well is any uncased artificial excavation, by any method, that uses the heat exchange capacity of the earth for heating and cooling, in which excavation the ambient ground temperature is 30 degrees Celsius (86 degrees Fahrenheit) or less, and which excavation uses a closed loop fluid system to prevent the discharge or escape of its fluid into surrounding aquifers or other geologic formations. Geothermal heat exchange wells include ground source heat pump wells.

Test Wells (Hole)

Test wells are constructed to obtain information needed for design of other wells. Test wells should not be confused with "exploration holes", which are temporary. Test wells are cased and can be converted to other uses such as groundwater monitoring and, under certain circumstances, to production wells.

Recharge, Injection or Air Conditioning Wells

Wells constructed to introduce water into the ground as a means of replenishing groundwater basins, repelling the intrusion of seawater, disposing of wastewater, or returning to the groundwater which has been used as a coolant in air conditioning processes. These wells are constructed under the jurisdiction of Regional Water Quality Control Boards under the authority of the California Water Code and California Public Resources Code. They also include "dry" wells, "drainage" wells and "sewer" wells.

Exploration Hole (Boring) and Soil Vapor Probe

Exploration holes (or Borings) and Cone Penetrometer Tests (CPT) for the purpose of determining hydrological conditions at a site, which are conducted at a depth greater than 10 feet below ground surface in the vadose zone or at any depth in the saturated zone, are required to submit a work plan and application to the Drinking Water Program. If an exploration hole (or Boring) or Cone Penetrometer Test (CPT) does not exceed 10 feet below ground surface and is not located within the saturated zone, a work plan and application is not required.

No permit is required for Soil Vapor Probe installed in vadose zone. A permit will be required if they reach saturated zone during the installation of the probe.

Shallow Anodes

Installation of anodes for pipeline protection at a depth of less than 50 feet deep are "legally" considered "shallow anodes", not cathodic protection wells. Shallow anodes do not require a well permit.

Dewatering / Stabilizing Wells

Dewatering or stabilizing wells are those wells installed for the purpose of dewatering excavations during construction or stabilizing hillsides and earth embankments. These wells do not require a well permit.

Oil and Gas Wells or Geothermal Wells Constructed in the State's Geothermal Resources Areas

Wells constructed under the jurisdiction of the Department of Conservation, California Geologic Energy Management Division shall not require a well permit.

Soil Vapor Extraction Wells

Soil vapor extraction wells use vacuum pressure to remove volatile and some semi-volatile contaminants (VOCs and SVOCs) from the soil. These wells may need a well permit. If these types of wells unexpectedly penetrate a subsurface aquifer, the contractor, driller, or consultant must contact Public Health for the purpose of evaluating the need for standard measures to protect the aquifer and for a well permit