Environmental Monitoring

Waste & Materials Management's Environmental Monitoring Program

GEMS Database Glossary of Terms & Definitions

Active: The sampling point is currently being monitored.
Analysis Date: The date on which the analysis for a particular parameter was completed.
Analysis Method (Code): The name or number of the published approach to determining the result used by the laboratory or field technician.
Common Name: The name used by a facility to identify a sampling point. Monitoring wells are commonly numbered consecutively and often referred to as MW-1, MW-2, and so forth. A Wisconsin Unique Well Number is also used with the common name to distinguish these wells apart.
Downgradient: When applied to groundwater at a particular location, it means that prior to reaching that location the groundwater has flowed under or through a facility or site. Sample results may show the effects of the facility or site activities when compared to upgradient results (see also sidegradient).
Duplicate Sample #: The duplicate number indicates whether a particular sample was a duplicate (two or more samples collected from the same point) and the number of the duplicate if more than one was collected.
Enforcement Standards (ESs): Groundwater quality standards in Chapter NR 140, Wisconsin Administrative Code.
Facility Address: The city or town and the street address of the facility or site.
Facility Contact: The contact name(s) and address(es) for a facility.
Facility Name: The name of the facility or site.
Facility Owner: The owner of the facility or site.
Facility Search: A query scheme designed to access monitoring data in GEMS by identifying facilities.
FID: A 9 digit facility identification number assigned by the DNR for tracking and consolidated environmental billing.
GEMS: The Groundwater & Environmental Monitoring System Database.
GEMS Contact: The contact name(s) and address(es) for a facility.
GEMS Point: The location from which the sample is collected.
Gradient Position: Identification of the position of a groundwater monitoring point relative to the facility or site and local groundwater flow (i.e. upgradient, downgradient, sidegradient). See Linked Points for additional information.
Lab ID: The certification number assigned by the DNR to a lab for unique identification.
License No.: A five-digit number assigned to each licensed facility or site that uniquely identifies that facility or site. See Monitoring ID.
Limit of Detection (LOD): The lowest concentration of a substance that can be determined using a particular method of analysis.
Limit of Quantitation (LOQ): The level above which a quantifiable concentration can be measured in a sample with a specific degree of confidence. Current methods tend to be more sensitive and accurate than previous ones, therefore historical data may display a wide range of values.
Linked Points: Indicates whether another facility or site also uses this monitoring point. The gradient position for any linked points is not indicated because the point may be upgradient from one facility while downgradient from another one.
Monitoring ID: A five-digit number assigned to each unlicensed facility or site, such as a small size construction and demolition waste landfill, that uniquely identifies that facility or site. See License No.
Monitoring Points: A list of all sampling points for a specific facility, these may include landfill gas, surface water, or groundwater sampling points. Some of the listed points, if they represent an actual monitoring well rather than a sampling location (ex. a specific spot by a stream or pond) may have been damaged and replaced by a newer well, and abandoned by either physically removing the well or filling it with cement to seal it. A replacement well is normally designated by using the original name and adding a "R" to the end of the name.
Monitoring Well: A monitoring well is a water table observation well or a piezometer established to examine the physical and/or chemical characteristics of the groundwater at a particular location.
Non Subtitle D Well: A monitoring well that has been identified for use to assess compliance only with the Wisconsin groundwater regulations (see Subtitle D Well).
Parameter Code: A five-digit code assigned for each chemical compound or parameter contained in the database. The parameter code is based on agency parameter codes, most of which were originally created for the US EPA STORET database.
Piezometer: A groundwater monitoring well established to examine the characteristics of the groundwater below the water table surface. Piezometers generally have 2 to 5 foot screen lengths. See Water Table Observation Well.
Point Count: The number of monitoring points established in GEMS that are assigned to a given facility or site.
Point ID: A three-digit code that along with a Monitoring ID or License No. uniquely defines a specific sampling point in the database.
Point Status: dentifies whether the monitoring point is currently active (A) or has been temporarily discontinued (I) or abandoned permanently (P) or is planned to be installed in the future (L). Some private wells are maintained strictly for sample collection after a new source of water has been established and are labeled as active potable - not consumed (N).
Point Type: Identifies the type of point from which the sample was collected, such as a gas probe, leachate collection system or a water table observation well.
Preventive Action Limits (PALs): Groundwater quality limits established in Chapter NR 140, Wisconsin Administrative Code, to be lower values than Enforcement Standards. PALs are designed to trigger a review of water quality conditions and potential responses in advance of violations of the Enforcement Standards.
Previous Name: Any former common name used for the monitoring point.
Public Land Survey (PLS): A system for identifying and locating parcels of land. See Survey Range, Survey Section, Survey Township.
Quality Control Flags: Additional information associated with each parameter result to help assess the validity of the result.
Range: See Survey Range.
Report Period Date: The first date of the reporting period for which the sample was required to be collected.
Reporting Limit (RL): The concentration or value below which the laboratory will not accurately report a result for the parameter indicated (similar to the Limit of Detection, but not formally recognized).
Result Amount: The measured quantity or concentration of a substance in a sample as measured by a laboratory or field instrument, associated with some Result Units.
Result Count: The number of parameters for which there are results in GEMS for a particular sampling date.
Result Qualifier: An identifier is sometimes associated with one or more results in a batch of analytical data submitted to the DNR, which provides additional information on the quality of the result provided for the parameter indicated.
Result Units: The measured quantity or concentration for each parameter is expressed as a unit of measure such as degrees Celsius, Milligrams per liter (mg/L) or micrograms per liter (ug/L).
Results for Parameter: The number of separate samples for which there are results in GEMS for a particular parameter at a given monitoring point.
Sample Collector: The name of the individual or company that collected the sample.
Sample Date: Date on which the sample was collected.
Sample ID: The identification number or code assigned by a lab to a sample for unique identification in order to maintain accurate records.
Section: See Survey Section.
Sidegradient: When applied to groundwater at a particular location, it means the flow path of groundwater relative to a facility location appears to be neither upgradient nor downgradient of a facility or site. Sample results may or may not show effects of any activities at that facility or sited when compared to upgradient results.
Subtitle D Well: A monitoring well that has been identified for use to assess compliance with Federal regulations established by the US EPA under the Resource Conservation and Recovery Act (RCRA) Subtitle D which covers municipal solid waste landfills.
Survey Range: Two-digit Public Land Survey (PLS) range number followed by a single letter indication East or West of the survey origin. Ranges are numbered consecutively from the survey origin (e.g. Range 1 West is the first one west of the survey origin and is displayed as R1W). A single combination of a survey range and survey township is commonly known as a "township" (not to be confused with the Wisconsin statutory municipal township). Such a township is an area that is six miles by six miles in size subdivided into sections that are one mile by one mile in size (thus there are 36 sections per township).
Survey Section: Two-digit Public Land Survey (PLS) section identification number. Sections are usually one square mile. Thirty-six sections make up a one PLS township. Valid numbers are 01 - 36, with the section numbers assigned following a specific pattern with a township, starting the upper-right hand corner (see diagram below).
Survey Township: Two-digit Public Land Survey (PLS) Township number followed by a single letter indication North or South of the of the survey origin (in Wisconsin, all PLS townships are North of the survey origin on the Illinois border). Townships are numbered consecutively from the survey origin (e.g. Township 1 North is the first one north of the Southern border). A single combination of a survey range and survey township is commonly known as a "township" (not to be confused with the Wisconsin statutory municipal township). A township is an area that is six miles by six miles in size subdivided into sections that are one mile by one mile in size (thus there are 36 sections per township).
Township: See Survey Township.
Upgradient: When applied to groundwater at a particular location, it means that water at this point will later flow under or through a facility or site. Upgradient monitoring points are often used to evaluate any impact that a facility may be having on downgradient or sidegradient water quality.
WI Unique Well Number: A five-character identification assigned to all wells in Wisconsin since 1988. The number is used to keep track of groundwater quality in a specific well over time and is tied to well location and construction information. It is made up of two alphabetic characters followed by three numeric characters (e.g. AB123).
WTM: Wisconsin Transverse Mercator.
WTM Easting: Defined as meters East of the Wisconsin Transverse Mercator (WTM) coordinate system y-axis based on the North American Datum of 1927. (Example: 652343.12)
WTM Northing: Defined in meters North of the Wisconsin Transverse Mercator (WTM) coordinate system x-axis based on the North American Datum of 1927. (Example 534023.81)
Water Table: The water table is the boundary between saturated soil and/or rock material and non-saturated soil or rock material. The water table is the level at which water stands in a shallow well. The water table is not flat over great distances, rather, it has peaks and valleys that usually mimic the shape of the land above it.
Water Table Observation Well: A groundwater monitoring well established to examine the characteristics of groundwater at the water table. Water table observation wells commonly have 10 - 15 foot screen lengths constructed to intersect the water table. See Piezometer.
X Coordinate: Defined as distance East or West of baseline.
Y Coordinate: Defined as distance North or South of baseline.

GEMS Data Search

Last Revised: Monday November 06 2006