15A NCAC 02E .0507 DEFINITIONS

The following is a list of definitions for terms found in Section .0500 of this Subchapter:

(1) Approved base rate: The larger of a person's January 1, 1997 through December 31, 1997 or August 1, 1999 through July 31, 2000 annual water use rate from the Cretaceous aquifer system, or an adjusted water use rate determined by the Division based upon documentation of the following information:

(a) water use reductions made since January 1, 1992;

(b) use of wells for which funding has been approved or for which plans have been approved by the Department of Environmental Quality by August 1, 2002;

(d) other information pertaining to water use during the time periods specified.

(2) Aquifer: Water-bearing earth materials that are capable of yielding water in usable quantities to a well or spring.

(3) Aquifer recharge: The addition of water to the zone of saturation.

(4) Aquifer storage and recovery program (ASR): Controlled injection of water into an aquifer with the intent to store water in the aquifer for subsequent withdrawal and use.

(5) Confining unit: A geologic formation that does not yield usable quantities of water to wells or springs. Confining units separate aquifers and slow the movement of ground water.

(6) Cretaceous aquifer system: A system of aquifers in the North Carolina coastal plain that is comprised of water-bearing earth materials deposited during the Cretaceous period of geologic time. The extent of the Cretaceous Aquifer System is defined in the hydrogeological framework and includes the Peedee, Black Creek, Upper Cape Fear, and Lower Cape Fear aquifers.

(7) Cretaceous aquifer system zones: Regions established in the fresh water portion of the Cretaceous aquifer system that delimit zones of salt water encroachment, dewatering, and declining water levels. These zones are designated on the paper and digital map entitled "Central Coastal Plain Capacity Use Area Cretaceous Aquifer Zones" (CCPCUA) on file in the Office of the Secretary of State. These zones encompass areas sensitive to over-development because aquifer withdrawal rates can exceed recharge rates and includes the regions where, between August 1, 2002 and July 31, 2019, Cretaceous Aquifer system zone users were required to reduce withdrawals from their Approved Base Rates up to 30 percent in the declining water level zone and up to 75 percent in the dewatering and salt water encroachment zones. Intermittent users and users of wells exclusively screened or open to the Peedee aquifer were not required to reduce withdrawals.

(8) Dewatering: Dewatering occurs when aquifer water levels are depressed below the top of a confined aquifer or water table declines adversely impact the resource.

(9) Flat rates: Unit price remains the same regardless of usage within customer class.

(10) Fresh water: Water containing chloride concentrations less than 250 milligrams per liter.

(11) Gravel pack: Sand or gravel sized material inside the well bore and outside the well screen and casing.

(12) Ground water: Water in pore spaces or void spaces of subsurface sediments or consolidated rock.

(13) Hydrogeological framework: A three-dimensional representation of aquifers and confining units that is stored in Division data bases and may be adjusted by applicant supplied information.

(14) Increasing block rates: Unit price increases with additional usage.

(15) Intermittent users: Persons who withdraw ground water less than 60 days per calendar year or who withdraw less than 15 million gallons of ground water in a calendar year; or aquaculture operations registered by the Board of Agriculture in accordance with G.S. 106-761 using water for the initial filling of ponds or refilling of ponds no more frequently than every five years.

(16) Observation well: A non-pumping well screened in a particular aquifer where water levels can be measured and water samples can be obtained.

(17) Pumping water level: The depth to ground water in a pumping well as measured from a known land surface elevation. Measurements shall be made four hours after pumping begins. Measurements shall be within accuracy limits of plus or minus 0.10 feet.

(18) Quantity based surcharges: Surcharges billed with usage over a certain determined quantity.

(19) Recharge rate: The rate of which water replenishes an aquifer.

(20) Salt water: Water containing chloride concentrations equal to and in excess of 250 milligrams per liter.

(21) Salt water encroachment: The lateral or vertical migration of salt water toward areas occupied by fresh water. This may occur in aquifers due to natural or man-made causes.

(22) Seasonal rates: Unit price changes according to the season.

(23) Static water level: The depth to ground water in a non-pumping well as measured from a known land surface elevation. Measurements shall be made after pumping has ceased for 12 hours. Measurements shall be within accuracy limits of plus or minus 0.10 feet.

(24) Unaccounted for water: The difference between the total water entering the system, including produced and purchased, and the total metered or otherwise accounted for water usage.

(25) Water table: The water level in an unconfined aquifer.

History Note: Authority G.S. 143-215.14;

Eff. August 1, 2002;

Readopted Eff. January 1, 2022.