Glossary
A
Accumulation Sampler:
A technology that concentrates the target chemical on a selective collecting medium such as an absorbent or absorbent solid, a solvent, or chemical reagent.
Active Sampling:
A method that relies on the mechanical action of sampling equipment to draw the medium and contaminants into the sampling device, causing deviations from the natural flow or ambient conditions.
Ambient Air:
For the purpose of this document, ambient air is equivalent to outdoor air.
C
Chemical (within the parameters of this document):
A generic term referring to an element or compound that is the target for sampling with the technology in question. This term is used in place of other common terms such as analyte, constituent, compound, contaminant, or contaminant of concern.
D
Dalton:
The unit used for the molecular weight cutoff (MWCO) by the manufacturers of dialysis membranes. It is a measure of what size molecules will go through or be excluded by the membrane. 1 Dalton=1 gram/mole, but all dialysis membranes are sold by MWCO values in Daltons.
Data quality objective (DQO):
An approach used to systematically plan for collecting environmental data of a known quality and quantity to support decisions.
E
Equilibrium sampler:
A technology that functions in a selected medium where chemicals reach concentration equivalence between the medium and the sampler through diffusion.
F
Field Parameters:
Measurements that provide information about the state and surroundings of the media in question. Examples include, but are not limited to, pH, temperature, conductivity, turbidity, dissolved oxygen, etc.
G
Grab sampler:
A device that recovers a sample of the selected medium representing the conditions at the sampling point, including any chemicals present, at the moment of sample collection or a period surrounding sample collection.
Groundwater:
Water that can be found in the subsurface in the annular spaces between soil, sand, and rock and is accessed by monitoring wells.
I
Indoor Air
The air present within buildings and structures that may be closed or sealed from exterior air.
M
Media/medium:
Soil, water, air, or any other parts of the environment that may contain contaminants
Minimum residence time:
The duration a sampling device remains in the medium for it to collect a representative sample. For groundwater, this includes well restabilization time.
Monitoring well/probe:
A device constructed in accordance with state or local regulations to obtain access to media.
N
NAPL:
The acronym for non-aqueous phase liquid. Refers to typically organic liquids that are immiscible or not soluble in water. There are two types of NAPL: light nonaqueous phase liquids (LNAPL), which are less dense than water, and dense nonaqueous phase liquids (DNAPL), which are denser than water.
Nonpassive sampler:
Technologies that do not fully meet the definition of active or passive sampling in this document.
O
Outdoor Air:
The air present exterior to a building or within structures that cannot be sealed from external sources.
P
Passive sampling:
A method that acquires a sample from a discrete location without inducing active media transport.
Polymeric samplers:
A technology that contains a hydrophobic polymer that absorbs organic compounds present in the media sampled.
Pore water:
Water located within the pore spaces between sediment particles that may represent the mobile water interacting between groundwater and surface water within permanent surface water features or intermittently flooded features (such as seasonal streams, intertidal zones, or stormwater swales/basins). This document primarily references sediment pore water; however, the information may also apply to soil pore water.
S
Sediment:
A medium consisting of primarily solid minerals and/or organic particles that are deposited as a result of water or wind transportation.
Soil:
Unconsolidated material that overlies bedrock.
Soil gas (soil vapor):
Gaseous elements and chemicals located in the spaces between soil particles within the vadose zone.
Surface water:
Permanent or reoccurring water open to the atmosphere under either high-flow (rivers or streams) or low-flow (ponds, oceans, or lakes) conditions.