Terms & Definitions

ADEM- Alabama Department of Environmental Management

ADPH- Alabama Department of Public Health

AMSL- Above mean sea level

Aquifer- An underground, water-bearing layer of earth, porous rock, sand or gravel, through which water can seep or be held in natural storage (also referred to as groundwater)

ARARs- Applicable or Relevant and Appropriate Requirements

Bentonite Seal- A clay that expands when mixed with water. Used to seal area around pipe that could allow run-off from the surface into the piezometer or well

BLS- below land surface

BTEX- benzene, toluene, ethyl benzene, and xylenes. Petroleum hydrocarbons often detected in groundwater near fuel releases

COC- Constituent of Concern

COG- Community Outreach Group-A group of citizens who live, work or own property in downtown Montgomery in the area near the Capital City Plume

EPA- Environmental Protection Agency

Groundwater- water present below ground surface (see also aquifer). Groundwater monitoring wells-devices installed into the ground to allow access and collection of groundwater. Groundwater monitoring wells are used to assess concentrations of contaminants in groundwater.

ug/l- Measurement of concentration of contaminant in water in micrograms per liter or parts per billion (ex. One part per billion is $1 out of $1,000,000,000)

ug/kg- Measurement of concentration of contaminant in soil in micrograms per kilogram or parts per billion)

mg/l- Measurement of concentration of contaminant in water in milligrams per liter or parts per million (ex. One part per million is $1 out of $1,000,000)

mg/kg- Measurement of concentration of contaminant in soil in milligrams per kilogram or parts per million

PCE- tetrachloroethylene or perchloroethylene

Permeability- the ability of a material to allow the passage of liquid, such as water, through rocks or soil. Permeable materials, such as gravel or sand, allow water to move quickly through them, whereas impermeable materials, such as clay and silt, do not allow water to flow freely.

Plume- A body of contaminated groundwater originating from a specific source and influenced by such factors as the local groundwater flow pattern, density of the contaminant, and character of the aquifer

Potable water- Water of suitable quality for drinking

ppb- parts per billion

ppm- parts per million

Piezometer- A device installed to monitor groundwater levels

Purge-To remove stagnant water or vapor from monitoring device

QA/QC- Quality Assurance/Quality Control

Remediation- The process of reducing the concentration of a contaminant(s) in air, water, or soil media to a specific level

Representative sample- A sample that properly depicts the chemical and physical character of the in-place groundwater or soil

Solubility- The amount of mass of a compound that will dissolve in a unit volume of solution

Summa Canister- An airtight, stainless-steel container. The air being sampled is “drawn” into the canister by a vacuum over a period of time eliminating the needs for pumps

Surface water- All water naturally open to the atmosphere (rivers, lakes, reservoirs, ponds, streams, impoundments, seas, estuaries, creeks, etc.)

TCE- Trichloroethylene

Topography- The physical features of a surface area including relative elevations and the position of natural and man-made features

Turbidity- The amount of solid particles that are suspended in water and that cause light rays shining through water to scatter. Turbidity makes water cloudy or opaque in extreme cases.

VOC- Volatile organic compound-Any organic compound which evaporates readily to the atmosphere

Volatile- Any substance which evaporates readily

Vapor migration- The separation of vapors from a subsurface contaminant source, such as soil or groundwater.

Water table- The level below which the ground is completely saturated with water (also known as water level). It can be measured by installing shallow wells extending a few feet into the zone of saturation and then measuring the water level in those wells