Copy of `EPA - Environmental Terms Glossary`

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EPA - Environmental Terms Glossary Category: Earth and Environment Date & country: 13/09/2007, USA Words: 1829

Pressure, Total
In flowing air, the sum of the static and velocity pressures.

Pressure, Velocity
In flowing air, the pressure due to velocity and density of air.

Pretreatment
Processes used to reduce, eliminate, or alter the nature of wastewater pollutants from non-domestic sources before they are discharged into publicly owned treatment works (POTWs).

Prevalent Level Samples
Air samples taken under normal conditions (also known as ambient background samples).

Prevalent Levels
Levels of airborne contaminant occurring under normal conditions.

Primacy
Having the primary responsibility for administering and enforcing regulations.

Primary Drinking Water Regulation
Applies to public water systems and specifies a contaminant level, which, in the judgment of the EPA Administrator, will not adversely affect human health.

Primary Effect
An effect where the stressor acts directly on the ecological component of interest, not on other parts of the ecosystem. (See secondary effect.)

Primary Standards
National ambient air quality standards designed to protect human health with an adequate margin for safety. (See National Ambient Air Quality Standards, secondary standards.)

Primary Treatment
First stage of wastewater treatment in which solids are removed by screening and settling.

Primary Waste Treatment
First steps in wastewater treatment; screens and sedimentation tanks are used to remove most materials that float or will settle. Primary treatment removes about 30 percent of carbonaceous biochemical oxygen demand from domestic sewage.

Prions
Microscopic particles made of protein that can cause disease.

Prior Appropriation
A doctrine of water law that allocates the rights to use water on a first-come, first-served basis.

Probability of Detection
The likelihood, expressed as a percentage, that a test method will correctly identify a leaking tank.

Process Variable
A physical or chemical quantity which is usually measured and controlled in the operation of a water treatment plant or industrial plant.

Process Verification
Verifying that process raw materials, water usage, waste treatment processes, production rate and other facts relative to quantity and quality of pollutants contained in discharges are substantially described in the permit application and the issued permit.

Process Wastewater
Any water that comes into contact with any raw material, product, byproduct, or waste.

Process Weight
Total weight of all materials, including fuel, used in a manufacturing process; used to calculate the allowable particulate emission rate.

Producers
Plants that perform photosynthesis and provide food to consumers.

Product Level
The level of a product in a storage tank.

Product Water
Water that has passed through a water treatment plant and is ready to be delivered to consumers.

Project XL
An EPA initiative to give states and the regulated community the flexibility to develop comprehensive strategies as alternatives to multiple current regulatory requirements in order to exceed compliance and increase overall environmental benefits.

Propellant
Liquid in a self-pressurized pesticide product that expels the active ingredient from its container.

Proportionate Mortality Ratio (PMR)
The number of deaths from a specific cause in a specific period of time per 100 deaths from all causes in the same time period.

Proposed Plan
A plan for a site cleanup that is available to the public for comment.

Proteins
Complex nitrogenous organic compounds of high molecular weight made of amino acids; essential for growth and repair of animal tissue. Many, but not all, proteins are enzymes.

Protocol
A series of formal steps for conducting a test.

Protoplast
A membrane-bound cell from which the outer wall has been partially or completely removed. The term often is applied to plant cells.

Protozoa
One-celled animals that are larger and more complex than bacteria. May cause disease.

Public Comment Period
The time allowed for the public to express its views and concerns regarding an action by EPA (e.g. a Federal Register Notice of proposed rule-making, a public notice of a draft permit, or a Notice of Intent to Deny).

Public Health Approach
Regulatory and voluntary focus on effective and feasible risk management actions at the national and community level to reduce human exposures and risks, with priority given to reducing exposures with the biggest impacts in terms of the number affected and severity of effect.

Public Health Context
The incidence, prevalence, and severity of diseases in communities or populations and the factors that account for them, including infections, exposure to pollutants, and other exposures or activities.

Public Hearing
A formal meeting wherein EPA officials hear the public's views and concerns about an EPA action or proposal. EPA is required to consider such comments when evaluating its actions. Public hearings must be held upon request during the public comment period.

Public Notice
1. Notification by EPA informing the public of Agency actions such as the issuance of a draft permit or scheduling of a hearing. EPA is required to ensure proper public notice, including publication in newspapers and broadcast over radio and television stations. 2. In the safe drinking water program, water suppliers are required to publish and broadcast notices when pollution problems are discovered.

Public Water System
A system that provides piped water for human consumption to at least 15 service connections or regularly serves 25 individuals.

Pumping Station
Mechanical device installed in sewer or water system or other liquid-carrying pipelines to move the liquids to a higher level.

Pumping Test
A test conducted to determine aquifer or well characteristics.

Purging
Removing stagnant air or water from sampling zone or equipment prior to sample collection.

Putrefaction
Biological decomposition of organic matter; associated with anaerobic conditions.

Putrescible
Able to rot quickly enough to cause odors and attract flies.

Pyrolysis
Decomposition of a chemical by extreme heat.

Qualitative Use Assessment
Report summarizing the major uses of a pesticide including percentage of crop treated, and amount of pesticide used on a site.

Quality Assurance-Quality Control
A system of procedures, checks, audits, and corrective actions to ensure that all EPA research design and performance, environmental monitoring and sampling, and other technical and reporting activities are of the highest achievable quality.

Quench Tank
A water-filled tank used to cool incinerator residues or hot materials during industrial processes.

Radiation
Transmission of energy though space or any medium. Also known as radiant energy.

Radiation Standards
Regulations that set maximum exposure limits for protection of the public from radioactive materials.

Radio Frequency Radiation
(See non-ionizing electromagnetic radiation.)

Radioactive Decay
Spontaneous change in an atom by emission of of charged particles and/or gamma rays; also known as radioactive disintegration and radioactivity.

Radioactive Substances
Substances that emit ionizing radiation.

Radioactive Waste
Any waste that emits energy as rays, waves, streams or energetic particles. Radioactive materials are often mixed with hazardous waste, from nuclear reactors, research institutions, or hospitals.

Radioisotopes
Chemical variants of radioactive elements with potentially oncogenic, teratogenic, and mutagenic effects on the human body.

Radionuclide
Radioactive particle, man-made (anthropogenic) or natural, with a distinct atomic weight number. Can have a long life as soil or water pollutant.

Radius of Influence
1. The radial distance from the center of a wellbore to the point where there is no lowering of the water table or potentiometric surface (the edge of the cone of depression); 2. the radial distance from an extraction well that has adequate air flow for effective removal of contaminants when a vacuum is applied to the extraction well.

Radius of Vulnerability Zone
The maximum distance from the point of release of a hazardous substance in which the airborne concentration could reach the level of concern under specified weather conditions.

Radon
A colorless naturally occurring, radioactive, inert gas formed by radioactive decay of radium atoms in soil or rocks.

Radon Daughters-Radon Progeny
Short-lived radioactive decay products of radon that decay into longer-lived lead isotopes that can attach themselves to airborne dust and other particles and, if inhaled, damage the linings of the lungs.

Radon Decay Products
A term used to refer collectively to the immediate products of the radon decay chain. These include Po-218, Pb-214, Bi-214, and Po-214, which have an average combined half-life of about 30 minutes.

Rainbow Report
Comprehensive document giving the status of all pesticides now or ever in registration or special reviews. Known as the 'rainbow report' because chapters are printed on different colors of paper.

Rasp
A machine that grinds waste into a manageable material and helps prevent odor.

Raw Agricultural Commodity
An unprocessed human food or animal feed crop (e.g., raw carrots, apples, corn, or eggs.)

Raw Sewage
Untreated wastewater and its contents.

Raw Water
Intake water prior to any treatment or use.

Re-entry
(In indoor air program) Refers to air exhausted from a building that is immediately brought back into the system through the air intake and other openings.

Reactivity
Refers to those hazardous wastes that are normally unstable and readily undergo violent chemical change but do not explode.

Reaeration
Introduction of air into the lower layers of a reservoir. As the air bubbles form and rise through the water, the oxygen dissolves into the water and replenishes the dissolved oxygen. The rising bubbles also cause the lower waters to rise to the surface where they take on oxygen from the atmosphere.

Real-Time Monitoring
Monitoring and measuring environmental developments with technology and communications systems that provide time-relevant information to the public in an easily understood format people can use in day-to-day decision-making about their health and the environment.

Reasonable Further Progress
Annual incremental reductions in air pollutant emissions as reflected in a State Implementation Plan that EPA deems sufficient to provide for the attainment of the applicable national ambient air quality standards by the statutory deadline.

Reasonable Maximum Exposure
The maximum exposure reasonably expected to occur in a population.

Reasonable Worst Case
An estimate of the individual dose, exposure, or risk level received by an individual in a defined population that is greater than the 90th percentile but less than that received by anyone in the 98th percentile in the same population.

Recarbonization
Process in which carbon dioxide is bubbled into water being treated to lower the pH.

Receiving Waters
A river, lake, ocean, stream or other watercourse into which wastewater or treated effluent is discharged.

Receptor
Ecological entity exposed to a stressor.

Recharge
The process by which water is added to a zone of saturation, usually by percolation from the soil surface; e.g., the recharge of an aquifer.

Recharge Area
A land area in which water reaches the zone of saturation from surface infiltration, e.g., where rainwater soaks through the earth to reach an aquifer.

Recharge Rate
The quantity of water per unit of time that replenishes or refills an aquifer.

Reclamation
(In recycling) Restoration of materials found in the waste stream to a beneficial use which may be for purposes other than the original use.

Recombinant Bacteria
A microorganism whose genetic makeup has been altered by deliberate introduction of new genetic elements. The offspring of these altered bacteria also contain these new genetic elements; i.e. they 'breed true.'

Recombinant DNA
The new DNA that is formed by combining pieces of DNA from different organisms or cells.

Reconstructed Source
Facility in which components are replaced to such an extent that the fixed capital cost of the new components exceeds 50 percent of the capital cost of constructing a comparable brand-new facility. New-source performance standards may be applied to sources reconstructed after the proposal of the standard if it is technologically and economically feasible to meet the standards.

Reconstruction of Dose
Estimating exposure after it has occurred by using evidence within an organism such as chemical levels in tissue or fluids.

Record of Decision (ROD)
A public document that explains which cleanup alternative(s) will be used at National Priorities List sites where, under CERCLA, Trust Funds pay for the cleanup.

Recovery Rate
Percentage of usable recycled materials that have been removed from the total amount of municipal solid waste generated in a specific area or by a specific business.

Recycle-Reuse
Minimizing waste generation by recovering and reprocessing usable products that might otherwise become waste (.i.e. recycling of aluminum cans, paper, and bottles, etc.).

Recycling Mill
Facility where recovered materials are remanufactured into new products.

Red Bag Waste
(See infectious waste.)

Red Border
An EPA document undergoing review before being submitted for final management decision-making.

Red Tide
A proliferation of a marine plankton toxic and often fatal to fish, perhaps stimulated by the addition of nutrients. A tide can be red, green, or brown, depending on the coloration of the plankton.

Redemption Program
Program in which consumers are monetarily compensated for the collection of recyclable materials, generally through prepaid deposits or taxes on beverage containers. In some states or localities legislation has enacted redemption programs to help prevent roadside litter. (See bottle bill.)

Reduction
The addition of hydrogen, removal of oxygen, or addition of electrons to an element or compound.

Reentry Interval
The period of time immediately following the application of a pesticide during which unprotected workers should not enter a field.

Reference Dose (RfD)
The RfD is a numerical estimate of a daily oral exposure to the human population, including sensitive subgroups such as children, that is not likely to cause harmful effects during a lifetime. RfDs are generally used for health effects that are thought to have a threshold or low dose limit for producing effects.

Reformulated Gasoline
Gasoline with a different composition from conventional gasoline (e.g., lower aromatics content) that cuts air pollutants.

Refueling Emissions
Emissions released during vehicle re-fueling.

Refuse
(See solid waste.)

Refuse Reclamation
Conversion of solid waste into useful products; e.g., composting organic wastes to make soil conditioners or separating aluminum and other metals for recycling.

Regeneration
Manipulation of cells to cause them to develop into whole plants.

Regional Response Team (RRT)
Representatives of federal, local, and state agencies who may assist in coordination of activities at the request of the On-Scene Coordinator before and during a significant pollution incident such as an oil spill, major chemical release, or Superfund response.

Registrant
Any manufacturer or formulator who obtains registration for a pesticide active ingredient or product.

Registration
Formal listing with EPA of a new pesticide before it can be sold or distributed. Under the Federal Insecticide, Fungicide, and Rodenticide Act, EPA is responsible for registration (pre-market licensing) of pesticides on the basis of data demonstrating no unreasonable adverse effects on human health or the environment when applied according to approved label directions.

Registration Standards
Published documents which include summary reviews of the data available on a pesticide's active ingredient, data gaps, and the Agency's existing regulatory position on the pesticide.