Glossary of Environmental Due Diligence Terms and Acronyms

Term or Acronym Definition of Term or Acronym Reference or Link
All Appropriate Inquiries (AAI)

The All Appropriate Inquiries (AAI) Final Rule is codified in federal law – Title 40 CFR Part 312. AAI is a process of evaluating a property's environmental conditions and assessing the likelihood of significant impacts or hazardous substance contamination. The specific reporting requirements for AAI are provided in 40 CFR §312.21.

AAI
Alquist-Priolo Special Studies Zone

Following the destructive February 9, 1971 Mw 6.6 San Fernando earthquake, the California legislature passed into law the Alquist-Priolo Earthquake Fault Zone (AP Act). The AP Act provides a mechanism for reducing losses from subsurface fault rupture on a statewide basis. The intent of the AP Act is to ensure public safety by prohibiting the siting of most structures for human occupancy across traces of active faults that constitute a potential hazard to structures from surface faulting or fault creep.

Alquist-Priolo
AMSL

Above Mean Sea Level (AMSL) is the elevation or altitude of any object, relative to the average sea level. 

AST

Above ground storage tank (AST) is any storage tank that is above ground.

ASTM

The American Society for Testing and Materials (ASTM), formally ASTM International, is a globally-recognized leader in the development and delivery of international voluntary consensus standards.

ASTM International
BTEX

Common gasoline constituents benzene, toluene, ethyl benzene, and xylenes, are often abbreviated “BTEX.”

CERCLA

The Comprehensive Environmental Response, Compensation, and Liability Act, 42 U.S. Code § 9601, et. seq., 1980 (CERCLA), is commonly known as “Superfund.” Enacted in response to the environmental horrors of Love Canal in New York, CERCLA uses industrial taxes to fund federal government responses to hazardous substance release sites. Updated in 1986, CERCLA also allows private parties to recover their response costs in specified situations. This powerful law imposes strict, joint and several liability.

CERCLA Overview
Closed Case

"Closed Case" refers to a former and/or closed environmental site assessment or remediation case that was overseen or managed by a Federal, State, or local oversight regulatory entity.

Controlled Recognized Environmental Condition (CREC)

A special category of Recognized Environmental Conditions (REC) resulting from past release of hazardous substances or petroleum products that has been addressed to the satisfaction of the applicable regulatory authority, with said contamination allowed to remain in place subject to the implementation of required controls. Controlled Recognized Environmental Conditions (CRECs) must be identified as RECs in the conclusion section of a Phase I - AAI environmental site assessment report.

ASTM E1527-13
Documented Environmental Condition™ (DEC)

Documented Environmental Condition™ (DEC) to identify the presence or likely presence of a hazardous substance or petroleum product in, on, or at a property, as derived from documents maintained with Federal, State, or local regulatory agencies and available publicly via online databases that:  (1) evidence a documented release to the environment; and/or (2) show documented conditions indicative of a past release, or that pose a material threat of a future release, to the environment (e.g., storage, handling, or waste management violations).

Dry Cleaner

Dry cleaning is any cleaning process for clothing and textiles using a chemical solvent other than water. California Disclosures™ Reports may identify properties where evidence of a commercial dry cleaner has been identified in the sources researched. Dry cleaners historically have, and currently may, use solvents containing volatile organic compounds (VOCs).

Environmental Professional

Someone who possesses sufficient specific education, training, and experience necessary to exercise professional judgment to develop opinions and conclusions regarding conditions indicative of releases or threatened releases of hazardous substances on, at, in, or to a property, sufficient to meet the objectives and performance factors of the final Environmental Protection Agency (EPA) All Appropriate Inquires (AAI) Rule (40 CFR Part 312).

EP
EPA

Federal Environmental Protection Agency (United States)

FEMA

Federal Emergency Management Agency (United States)

FEMA Flood Zone Map Designations

Flood zones are geographic areas that FEMA has defined according to varying levels of flood risk and types of flooding. For example, Zone X designates areas of moderate or minimal flood hazard based upon the principal source of flood in the area. Use the link provided to review the FEMA Flood Zone Definitions.

FEMA Flood Zone Definitions
Gas Station

A general commercial term for properties where the retail or wholesale refueling of automobiles occurs. Gas stations typically utilize underground storage tanks to store fuel and underground piping to convey fuel to the dispenser islands.  California Disclosures™ Reports may identify properties where evidence of a gas station has been identified in the sources researched.

Gasoline

A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in spark-ignition engines (U.S. Energy Information Administration)

GeoTracker

California State Water Resources Control Board’s publicly accessible website providing environmental data for regulated facilities.

GeoTracker
Groundwater

(1) Water that flows or seeps downward and saturates soil or rock, supplying springs or wells. The upper surface of the saturated zone is called the water table. (2) Water stored underground in rock crevices and in the pores of geologic materials that make up the Earth's crust.

USGS water science glossary of terms
Historical Recognized Environmental Condition (HREC)

A special category of Recognized Environmental Conditions (REC) constituting a past release of any hazardous substances or petroleum products that has occurred in connection with the property and has been addressed to the satisfaction of the applicable regulatory authority or meeting unrestricted use criteria established by a regulatory authority, without subjecting the property to any required controls.

ASTM E1527-13
Land Use Restriction, Environmental

Governmental agency-imposed restrictions, often recorded as covenants against title and “running with the land,” placing limits or requirements on future use of the burdened property due to environmental concerns (e.g., prohibition against use as a hospital or day care center, or against water well development).

Latitude

The angular distance north or south from the equator of a point on the Earth's surface, measured on the meridian of the point.

Liquefaction

Liquefaction occurs when loosely compacted granular soils that are saturated with water are subjected to seismic forces, effectively increasing the pore pressure and in turn, decreasing shear strength and vertical bearing capacity (County of Los Angeles, 2012). When the ground liquefies, sandy materials saturated with water can behave like a liquid, instead of like solid ground. The ground may sink or even pull apart (Assoc. of Bay Area Governments, 2001).

Longitude

The angular distance east or west on the Earth's surface, measured by the angle contained between the meridian of a particular place and some prime meridian, as that of Greenwich, England, and expressed either in degrees or by some corresponding difference in time.

MCLs

Maximum Contaminant Levels (MCLs) are standards set by governmental agencies for drinking water quality. An MCL is the legal threshold limit on the amount of a substance that is allowed in public water systems and is usually expressed as a concentration in milligrams (parts per million) or micrograms (parts per billion) per liter of water.

MCLs
Monitoring well

Wells drilled into groundwater for the purposes of groundwater level monitoring and the collection of groundwater samples for water quality testing. Monitoring wells are used to assess and monitor the types, amounts, and distribution of contaminants in groundwater.

MTBE

Methyl tertiary butyl ether (MTBE) is a gasoline additive that is also a regulated drinking water contaminant in California. MTBE has:

  • A primary MCL of 13 micrograms per liter (µg/L), established in 2000. Its 1999 public health goal is 13 µg/L, corresponding to the de minimis cancer risk derived from animal studies.
  • A secondary MCL of 5 µg/L, established in 1999. The secondary MCL addresses taste and odor concerns.
MTBE California
Open Case

An active environmental site assessment or remediation case being overseen or managed by a Federal, State, or local oversight regulatory entity.

PCE

Tetrachloroethylene (also known as tetrachloroethene, perchlorethylene, and "perc"), is a volatile organic compound with four chlorine molecules historically used in industries such as dry cleaning, circuit board manufacturing, and other applications that need degreasing. PCE is a human carcinogen, is persistent in the environment, and is frequently a driving factor in environmental investigations and site cleanups.

American Cancer Society
PE or P.E.

A Professional Engineer is a certified and licensed engineer. Typically, to become licensed, engineers must complete a four-year college degree, work under a Professional Engineer for at least four years, pass two intensive competency exams, and earn a license from their state's licensure board. To retain their licenses, PEs must continually maintain and improve their skills throughout their careers.

PG or P.G.

A Professional Geologist is typically a person who is a graduate of an institution of higher education with specified undergraduate or graduate work in a field of geology and professional geological work experience of a character appropriate to satisfy a state’s licensing board.

Phase I ESA AAI (ASTM E1527-13)

A Phase I Environmental Site Assessment (ESA) is a due diligence report prepared for a parcel of real estate with the objective of identifying real or potential environmental liabilities associated with a property and the surrounding properties. Key elements of a Phase I ESA include: an extensive regulatory database review, a review of historical records to evaluate potential environmental liabilities associated with past property uses, a detailed site inspection, and interviews with past and present owners, operators, and occupants. 

The specific reporting requirements for All Appropriate Inquiry (AAI) are provided in 40 CFR §312.21. ASTM E1527-13 is the Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process and has been developed by the ASTM to reflect the requirements described in 40 CFR §312.21.

Phase I ESA AAI
Phase II ESA

A more involved environmental site assessment that may be characterized by the need to collect samples for laboratory analytical testing and including an evaluation of contaminant concentrations and distribution in the subsurface (if contamination is detected).

ppb

Parts per billion (ppb).

For soil samples: 1 ppb = 1 microgram/kilogram (µg/kg)

For aqueous (e.g. groundwater) samples: 1 ppb = 1 microgram/liter (µg/L) = 0.001 milligram/liter (mg/L)

For vapor samples: parts per billion by volume of vapor is dependent upon the molecular weight of the compound(s).

ppm

Parts per million (ppm).

For soil samples: 1 ppm = 1 milligram/kilogram (mg/kg)

For aqueous (e.g. groundwater) samples: 1 ppm = 1 milligram/liter (mg/L) = 1,000 micrograms/liter (µg/L)

For vapor samples: parts per million by volume of vapor is dependent upon the molecular weight of the compound(s).

RCRA

The Resource Conservation and Recovery Act (RCRA), 42 U.S.C. §6901, et seq. (1976) regulates land-based disposal of waste and establishes the tracking requirements for hazardous waste; commonly referred to as "cradle to grave" tracking.

RCRA LQG

Pursuant to RCRA, see above, a Large Quantity Generator (LQG) generates 1,000 kilograms per month or more of hazardous waste, or more than 1 kilogram per month of acutely hazardous waste.

RCRA LQG
RCRA SQG

Pursuant to RCRA, see above, a Small Quantity Generator (SQG) generates more than 100 kilograms, but less than 1,000 kilograms, of hazardous waste per month.

RCRA SQG
Recognized Environmental Condition (REC)

A recognized environmental condition (REC) means the presence or likely presence of any hazardous substances or petroleum products in, on, or at a property: (1) due to any release to the environment; (2) under conditions indicative of a release to the environment; or (3) under conditions that pose a material threat of a future release to the environment. De minimis conditions are not recognized environmental conditions.

ASTM E1527-13
Seismic Hazard Mapping Act

The Seismic Hazards Mapping Act (SHMA) of 1990 (Public Resources Code, Chapter 7.8, Section 2690-2699.6) directs the Department of Conservation, California Geological Survey to identify and map areas prone to earthquake hazards of liquefaction, earthquake-induced landslides and amplified ground shaking. The purpose of the SHMA is to reduce the threat to public safety and to minimize the loss of life and property by identifying and mitigating these seismic hazards. The SHMA was passed by the legislature following the 1989 Loma Prieta earthquake.

SHMA Fact Sheet
Soil Gas

Soil Gas is defined by the EPA as gaseous elements and compounds in the small spaces between particles of the earth and soil. Soil gas is commonly sampled and analyzed for volatile organic compounds (VOCs) to physically investigate and determine the extent of vapor migration associated with releases of hazardous substances into the subsurface.

SWRCB

The California State Water Resources Control Board (SWRCB) was created by the legislature in 1967. The mission of the Water Board is to ensure the highest reasonable quality for waters of the state, while allocating those waters to achieve the optimum balance of beneficial uses. The joint authority of water allocation and water quality protection enables the Water Board to provide comprehensive protection for California's waters.

SWRCB
TCE

Trichloroethylene (also known as trichloroethene), is a volatile organic compound with three chlorine molecules historically used in industries that needed heavy degreasing. TCE is a human carcinogen, is persistent in the environment, and is frequently a driving factor in environmental investigations and site cleanups.

Report on Carcinogens: Webinar on TCE
Title 40 CFR Part 312

Federal regulation entitled: “Innocent Landowners, Standards for conducting All Appropriate Inquiries”

Title 40 CFR Part 312
UST

An underground storage tank (UST) is a tank and any underground piping connected to the tank that typically has at least 10 percent of its combined volume underground. Many USTs installed before 1980 consisted of bare steel pipes, which corrode over time and eventually result in leakage impacting soils and groundwater.

Vapor Migration

Vapor migration refers to the movement of volatile organic compounds (VOCs) through pore spaces in unsaturated soil. Contaminant sources for vapor migration include VOC contamination in groundwater (dissolved-phase) and/or in soil (adsorbed-phase), as well as contamination present in the vapor-phase. Vapor intrusion occurs when vapor-phase VOC contaminants migrate and enter a structure's interior space, typically through cracks, joints, or crawl-spaces.

VOC(s)

Volatile organic compounds (VOCs) is an umbrella term that includes 70-plus organic chemicals that have a high vapor pressure at room temperature. VOCs are numerous, varied, and ubiquitous and while some are naturally-occurring, many are man-made. The VOCs of interest to many environmental investigations include chemicals defined elsewhere herein such as benzene, toluene, ethyl-benzene, xylenes (BTEX), and the chlorinated solvents PCE and TCE.