NV Well Driller key terms

The pipe installed in a borehole to keep the hole open, prevent cave-in, and seal off unwanted water or contamination so that only the intended aquifer feeds the well.

The impermeable material placed in the space between the borehole wall and the casing, extending from land surface down to the required depth, to block surface and shallow water from moving along the outside of the casing.

A cement-based or bentonite mixture pumped into the annular space to harden into a low-permeability barrier that protects groundwater and stabilizes the borehole.

A mix of cement and water only, without sand, used where a strong, low-permeability annular seal is required; it is denser than bentonite slurry and sets hard.

A slotted or perforated section of casing set across a producing formation that lets water enter the well while holding back sand and gravel.

Sorted gravel placed in the annular space around a screen to filter formation sand from entering the well and to increase the effective producing area.

Uniformly graded sand or gravel installed between the screen and the formation so finer aquifer material is held back while water flows freely into the well.

The surface portion of the well seal and casing arrangement, including a watertight cap or seal, that keeps surface runoff, insects, and debris from entering the well.

A well in which water rises above the top of the confined aquifer under its own pressure, sometimes flowing at the surface without pumping.

A water-bearing layer bounded above and below by low-permeability material so that the water is under pressure greater than atmospheric at the top of the aquifer.

An aquifer whose upper boundary is the water table, open to atmospheric pressure through overlying permeable material.

A geologic formation or group of formations that stores and transmits enough groundwater to supply wells or springs in usable quantities.

The upper surface of the saturated zone in an unconfined aquifer, where pore pressure equals atmospheric pressure.

The imaginary level to which water in a confined aquifer would rise in a tightly cased well under its natural pressure.

The depth to the water surface in a well when the pump has been off long enough for the water level to stabilize, reflecting ambient aquifer conditions.

The depth to water measured in a well while it is being pumped at a steady rate, after drawdown has stabilized.

The difference between the static water level and the pumping water level in a well, representing the head lost to pump the well at that rate.

The pumping rate divided by the drawdown it produces, usually expressed in gallons per minute per foot; a higher value indicates a more productive well.

A controlled test in which a well is pumped at measured rates while water levels are recorded over time to estimate yield, specific capacity, and aquifer properties.

The roughly conical lowering of the water table or potentiometric surface around a pumping well, caused by drawdown.

The mutual reduction in water levels and yield that occurs when pumping wells are spaced closely enough that their cones of depression overlap.

A localized body of groundwater held above the main water table by a small lens of low-permeability material; it may supply a well briefly but is usually limited.

A use of water recognized as productive and reasonable under Nevada law, such as domestic, municipal, irrigation, stock, mining, or industrial supply.

The doctrine under which the first person to put water to beneficial use obtains a right with a priority date, and earlier rights are satisfied first in times of shortage.

The date a water right application is filed or a use is initiated, which fixes the right's rank relative to other rights on the same source.

The legal process of acquiring a right to use water by applying to the state, obtaining a permit, and putting the water to beneficial use.

The state-issued authorization allowing an applicant to develop a water supply and apply it to the stated beneficial use, subject to conditions and deadlines.

The document issued after a permitted use is perfected and verified, confirming the vested right, its amount, purpose, and priority date.

The filing and showing required to demonstrate that water has actually been applied to the authorized use, which supports issuance of a certificate.

A formal state proceeding to determine and confirm the relative rights of all claimants to water in a designated stream system or groundwater basin.

A groundwater area formally designated by the state so that withdrawals are administered, and new appropriations may be conditioned or restricted, based on supply conditions.

The credential issued by the state that authorizes a person or firm to drill, construct, or abandon water wells within the jurisdiction, subject to renewal and discipline.

The form a licensed driller files with the state before starting a well, identifying the location, proposed depth, use, and owner so the work can be tracked and approved.

The required record of a completed well reporting location, owner, dates, total depth, casing and screen details, seal, water levels, yield, and formations encountered.

The portion of a well record describing the sequence and thickness of soil and rock units penetrated, based on the driller's observations of cuttings and drilling behavior.

The field record kept during drilling that documents depth, formations, water strikes, casing set, and grouting, later used to complete the official well report.

The proper sealing of a well no longer in use, typically with grout or approved material placed to prevent intermixing of aquifers and contamination of groundwater.

The downward movement of water through soil and rock openings toward the water table, a key process in recharging unconfined aquifers.