P2— Pollution Prevention
PAG— Pesticide Assignment Guidelines
PAH— Polynuclear Aromatic Hydrocarbons
PAl— Performance Audit Inspection (CWA);
Pure Active Ingredient compound
PAM— Pesticide Analytical Manual
PAMS— Photochemical Assessment Monitoring
PAT— Permit Assistance Team (RCRA)
PATS— Pesticide Action Tracking System;
Pesticides Analytical Transport Solution
PBA— Preliminary Benefit Analysis (BEAD)
PCA— Principle Component Analysis
PCB— Polychlorinated Biphenyl
PCM— Phase Contrast Microscopy
PCN— Policy Criteria Notice
PCO— Pest Control Operator
PCSD— President’s Council on Sustainable
PDCI— Product Data Call-In
PFC— Perfluorated Carbon
PFCRA— Program Fraud Civil Remedies
PHC— Principal Hazardous Constituent
PHI— Pre-Harvest Interval
PHSA— Public Health Service Act
PI— Preliminary Injunction. Program
PIC— Products of Incomplete Combustion
PIGS— Pesticides in Groundwater Strategy
PIMS— Pesticide Incident Monitoring
PIN— Pesticide Information Network
PIN— Procurement Information Notice
PIP— Public Involvement Program
PIPQUIC— Program Integration Project
Queries Used in Interactive Command
PIRG— Public Interest Research Group
PIRT— Pretreatment Implementation Review
PIT— Permit Improvement Team
PITS— Project Information Tracking System
PLIRRA— Pollution Liability Insurance
and Risk Retention Act
PLM— Polarized Light Microscopy
PLUVUE— Plume Visibility Model
PM— Particulate Matter
PMAS— Photochemical Assessment Monitoring
PM2.5— Particulate Matter Smaller than
2.5 Micrometers in Diameter
PM10— Particulate Matter (nominally
10m and less)
PM15— Particulate Matter (nominally
15m and less)
PMEL— Pacific Marine Environmental Laboratory
PMN— Premanufacture Notification
PMNF— Premanufacture Notification Form
PMR— Pollutant Mass Rate
PMR— Proportionate Mortality Ratio
PMRS— Performance Management and Recognition
PMS— Program Management System
PNA— Polynuclear Aromatic Hydrocarbons
PO— Project Officer
POC— Point Of Compliance
POE— Point Of Exposure
POGO— Privately-Owned/ Government-Operated
POHC— Principal Organic Hazardous Constituent
POI— Point Of Interception
POM— Particulate Organic Matter. Polycyclic
POP— Persistent Organic Pollutant
POR— Program of Requirements
POTW— Publicly Owned Treatment Works
POV— Privately Owned Vehicle
PP— Program Planning
PPA— Planned Program Accomplishment
PPB— Parts Per Billion
PPE— Personal Protective Equipment
PPG— Performance Partnership Grant
PPIC— Pesticide Programs Information
PPIS— Pesticide Product Information
System; Pollution Prevention Incentives for
PPMAP— Power Planning Modeling Application
PPM/PPB— Parts per million/ parts per
PPSP— Power Plant Siting Program
PPT— Parts Per Trillion
PPTH— Parts Per Thousand
PQUA— Preliminary Quantitative Usage
PR— Pesticide Regulation Notice; Preliminary
PRA— Paperwork Reduction Act; Planned
PRATS— Pesticides Regulatory Action
PRC— Planning Research Corporation
PRI— Periodic Reinvestigation
PRM— Prevention Reference Manuals
PRN— Pesticide Registration Notice
PRP— Potentially Responsible Party
PRZM— Pesticide Root Zone Model
PS— Point Source
PSAM— Point Source Ambient Monitoring
PSC— Program Site Coordinator
PSD— Prevention of Significant Deterioration
PSES— Pretreatment Standards for Existing
PSI— Pollutant Standards Index; Pounds
Per Square Inch; Pressure Per Square Inch
PSIG— Pressure Per Square Inch Gauge
PSM— Point Source Monitoring
PSNS— Pretreatment Standards for New
PSU— Primary Sampling Unit
PTDIS— Single Stack Meteorological Model
in EPA UNAMAP Series
PTE— Potential to Emit
PTFE— Polytetrafluoroethylene (Teflon)
PTMAX— Single Stack Meteorological Model
in EPA UNAMAP series
PTPLU— Point Source Gaussian Diffusion
PUC— Public Utility Commission
PV— Project Verification
PVC— Polyvinyl Chloride
PWB— Printed Wiring Board
PWS— Public Water Supply/ System
PWSS— Public Water Supply System
Packaging— The assembly
of one or more containers and any other components
necessary to ensure minimum compliance with
a program’s storage and shipment packaging
requirements. Also, the containers, etc. involved.
Packed Bed Scrubber—
An air pollution control device in which emissions
pass through alkaline water to neutralize
hydrogen chloride gas.
Packed Tower— A pollution
control device that forces dirty air through
a tower packed with crushed rock or wood chips
while liquid is sprayed over the packing material.
The pollutants in the air stream either dissolve
or chemically react with the liquid.
Packer— An inflatable
gland, or balloon, used to create a temporary
seal in a borehole, probe hole, well, or drive
casing. It is made of rubber or non-reactive
Palatable Water— Water,
at a desirable temperature, that is free from
objectionable tastes, odors, colors, and turbidity.
Pandemic— A widespread
epidemic throughout an area, nation or the
Paper— In the recycling
business, refers to products and materials,
including newspapers, magazines, office papers,
corrugated containers, bags and some paperboard
packaging that can be recycled into new paper
Paper Processor/Plastics Processor—
Intermediate facility where recovered paper
or plastic products and materials are sorted,
decontaminated, and prepared for final recycling.
Parameter— A variable,
measurable property whose value is a determinant
of the characteristics of a system; e.g. temperature,
pressure, and density are parameters of the
Paraquat— A standard
herbicide used to kill various types of crops,
including marijuana. Causes lung damage if
smoke from the crop is inhaled.
Parshall Flume— Device
used to measure the flow of water in an open
Participation Rate— Portion
of population participating in a recycling
Particle Count— Results
of a microscopic examination of treated water
with a special “particle counter”
that classifies suspended particles by number
The mass of particulates per unit volume of
air or water.
Particulates— 1. Fine
liquid or solid particles such as dust, smoke,
mist, fumes, or smog, found in air or emissions.
2. Very small solids suspended in water; they
can vary in size, shape, density and electrical
charge and can be gathered together by coagulation
Measure of the sorption phenomenon, whereby
a pesticide is divided between the soil and
water phase; also referred to as adsorption
Parts Per Billion (ppb)/Parts
Per Million (ppm)— Units commonly used
to express contamination ratios, as in establishing
the maximum permissible amount of a contaminant
in water, land, or air.
Smoke— Inhalation of others’ tobacco
Passive Treatment Walls—
Technology in which a chemical reaction takes
place when contaminated ground water comes
in contact with a barrier such as limestone
or a wall containing iron filings.
(e.g., bacteria, viruses, or parasites) that
can cause disease in humans, animals and plants.
Pathway— The physical
course a chemical or pollutant takes from
its source to the exposed organism.
Pricing— Systems under which residents
pay for municipal waste management and disposal
services by weight or volume collected, not
a fixed fee.
Peak Electricity Demand—
The maximum electricity used to meet the cooling
load of a building or buildings in a given
Peak Levels— Levels of
airborne pollutant contaminants much higher
than average or occurring for short periods
of time in response to sudden releases.
The amount of a substance that is dissolved
in a solution compared to the amount that
could be dissolved in it.
Perched Water— Zone of
unpressurized water held above the water table
by impermeable rock or sediment.
Percolating Water— Water
that passes through rocks or soil under the
force of gravity.
Percolation— 1. The movement
of water downward and radially through subsurface
soil layers, usually continuing downward to
ground water. Can also involve upward movement
of water. 2. Slow seepage of water through
Performance Bond— Cash
or securities deposited before a landfill
operating permit is issued, which are held
to ensure that all requirements for operating
ad subsequently closing the landfill are faithful
performed. The money is returned to the owner
after proper closure of the landfill is completed.
If contamination or other problems appear
at any time during operation, or upon closure,
and are not addressed, the owner must forfeit
all or part of the bond which is then used
to cover clean-up costs.
Performance Data (For Incinerators)—
Information collected, during a trial burn,
on concentrations of designated organic compounds
and pollutants found in incinerator emissions.
Data analysis must show that the incinerator
meets performance standards under operating
conditions specified in the RCRA permit.
1. Regulatory requirements limiting the concentrations
of designated organic compounds, particulate
matter, and hydrogen chloride in emissions
from incinerators. 2. Operating standards
established by EPA for various permitted pollution
control systems, asbestos inspections, and
various program operations and maintenance
underwater plants and animals that are firmly
attached to solid surfaces such as rocks,
logs, and pilings.
Permeability— The rate
at which liquids pass through soil or other
materials in a specified direction.
Permissible Dose— The
dose of a chemical that may be received by
an individual without the expectation of a
significantly harmful result.
Permit— An authorization,
license, or equivalent control document issued
by EPA or an approved state agency to implement
the requirements of an environmental regulation;
e.g. a permit to operate a wastewater treatment
plant or to operate a facility that may generate
Persistence— Refers to
the length of time a compound stays in the
environment, once introduced. A compound may
persist for less than a second or indefinitely.
Pesticides that do not break down chemically
or break down very slowly and remain in the
environment after a growing season.
Personal Air Samples—
Air samples taken with a pump that is directly
attached to the worker with the collecting
filter and cassette placed in the worker’s
breathing zone (required under OSHA asbestos
standards and EPA worker protection rule).
A measurement collected from an individual’s
Personal Protective Equipment—
Clothing and equipment worn by pesticide mixers,
loaders and applicators and re-entry workers,
hazmat emergency responders, workers cleaning
up Superfund sites, et. al., which is worn
to reduce their exposure to potentially hazardous
chemicals and other pollutants.
Pest— An insect, rodent,
nematode, fungus, weed or other form of terrestrial
or aquatic plant or animal life that is injurious
to health or the environment.
Pest Control Operator—
Person or company that applies pesticides
as a business (e.g. exterminator); usually
describes household services, not agricultural
or mixture there of intended for preventing,
destroying, repelling, or mitigating any pest.
Also, any substance or mixture intended for
use as a plant regulator, defoliant, or desiccant.
Pesticide Regulation Notice—
Formal notice to pesticide registrants about
important changes in regulatory policy, procedures,
The amount of pesticide residue allowed by
law to remain in or on a harvested crop. EPA
sets these levels well below the point where
the compounds might be harmful to consumers.
PETE (Polyethylene Terepthalate)—
Thermoplastic material used in plastic soft
drink and rigid containers.
Petroleum— Crude oil
or any fraction thereof that is liquid under
normal conditions of temperature and pressure.
The term includes petroleum-based substances
comprising a complex blend of hydrocarbons
derived from crude oil through the process
of separation, conversion, upgrading, and
finishing, such as motor fuel, jet oil, lubricants,
petroleum solvents, and used oil.
Chemicals formed when gasoline breaks down
in contact with ground water.
pH— An expression of
the intensity of the basic or acid condition
of a liquid; may range from 0 to 14, where
0 is the most acid and 7 is neutral. Natural
waters usually have a pH between 6.5 and 8.5.
study of the way that drugs move through the
body after they are swallowed or injected.
The alkalinity in a water sample measured
by the amount of standard acid needed to lower
the pH to a level of 8.3 as indicated by the
change of color of the phenolphthalein from
pink to clear.
Phenols— Organic compounds
that are byproducts of petroleum refining,
tanning, and textile, dye, and resin manufacturing.
Low concentrations cause taste and odor problems
in water; higher concentrations can kill aquatic
life and humans.
Phosphates— Certain chemical
compounds containing phosphorus.
Phosphogypsum Piles (Stacks)—
Principal byproduct generated in production
of phosphoric acid from phosphate rock. These
piles may generate radioactive radon gas.
Phosphorus— An essential
chemical food element that can contribute
to the eutrophication of lakes and other water
bodies. Increased phosphorus levels result
from discharge of phosphorus-containing materials
into surface waters.
Phosphorus Plants— Facilities
using electric furnaces to produce elemental
phosphorous for commercial use, such as high
grade phosphoric acid, phosphate-based detergent,
and organic chemicals use.
Air pollutants formed by the action of sunlight
on oxides of nitrogen and hydrocarbons.
Photochemical Smog— Air
pollution caused by chemical reactions of
various pollutants emitted from different
Photosynthesis— The manufacture
by plants of carbohydrates and oxygen from
carbon dioxide mediated by chlorophyll in
the presence of sunlight.
Physical and Chemical Treatment—
Processes generally used in large-scale wastewater
treatment facilities. Physical processes may
include air-stripping or filtration. Chemical
treatment includes coagulation, chlorination,
or ozonation. The term can also refer to treatment
of toxic materials in surface and ground waters,
oil spills, and some methods of dealing with
hazardous materials on or in the ground.
Phytoplankton— That portion
of the plankton community comprised of tiny
plants; e.g. algae, diatoms.
remediation option for sites with widely dispersed
contamination at low concentrations.
Phytotoxic— Harmful to
Phytotreatment— The cultivation
of specialized plants that absorb specific
contaminants from the soil through their roots
or foliage. This reduces the concentration
of contaminants in the soil, but incorporates
them into biomasses that may be released back
into the environment when the plant dies or
Picocuries Per Liter pCi/L)—
A unit of measure for levels of radon gas;
becquerels per cubic meter is metric equivalent.
Piezometer— A nonpumping
well, generally of small diameter, for measuring
the elevation of a water table.
Pilot Tests— Testing
a cleanup technology under actual site conditions
to identify potential problems prior to full-scale
Plankton— Tiny plants
and animals that live in water.
Plasma-Arc Reactor— An
incinerator that operates at extremely high
temperatures; treats highly toxic wastes that
do not burn easily.
Plasmid— A circular piece
of DNA that exists apart from the chromosome
and replicates independently of it. Bacterial
plasmids carry information that renders the
bacteria resistant to antibiotics. Plasmids
are often used in genetic engineering to carry
desired genes into organisms.
chemoreactive compounds molded into rigid
or pliable construction materials, fabrics,
Plate Tower Scrubber—
An air pollution control device that neutralizes
hydrogen chloride gas by bubbling alkaline
water through holes in a series of metal plates.
Plug Flow— Type of flow
the occurs in tanks, basins, or reactors when
a slug of water moves through without ever
dispersing or mixing with the rest of the
water flowing through.
Plugging— Act or process
of stopping the flow of water, oil, or gas
into or out of a formation through a borehole
or well penetrating that formation.
Plume— 1. A visible or
measurable discharge of a contaminant from
a given point of origin. Can be visible or
thermal in water, or visible in the air as,
for example, a plume of smoke. 2 The area
of radiation leaking from a damaged reactor.
3. Area downwind within which a release could
be dangerous for those exposed to leaking
Plutonium— A radioactive
metallic element chemically similar to uranium.
PM-10/PM-2.5— PM 10 is
measure of particles in the atmosphere with
a diameter of less than ten or equal to a
nominal 10 micrometers. PM-2.5 is a measure
of smaller particles in the air. PM-10 has
been the pollutant particulate level standard
against which EPA has been measuring Clean
Air Act compliance. On the basis of newer
scientific findings, the Agency is considering
regulations that will make PM-2.5 the new
conditions characterized by permanent deposition
of substantial amounts of particulate matter
in the lungs and by the tissue reaction to
its presence; can range from relatively harmless
forms of sclerosis to the destructive fibrotic
effect of silicosis.
Point Source— A stationary
location or fixed facility from which pollutants
are discharged; any single identifiable source
of pollution; e.g. a pipe, ditch, ship, ore
pit, factory smokestack.
of Exposure— Estimating exposure by
measuring concentrations over time (while
the exposure is taking place) at or near the
place where it is occurring.
The point where disinfectant is applied and
water downstream of that point is not subject
to recontamination by surface water runoff.
Point-of-Use Treatment Device—
Treatment device applied to a single tap to
reduce contaminants in the drinking water
at the one faucet.
Pollen— The fertilizing
element of flowering plants; background air
any substance introduced into the environment
that adversely affects the usefulness of a
resource or the health of humans, animals,
Pollutant Pathways— Avenues
for distribution of pollutants. In most buildings,
for example, HVAC systems are the primary
pathways although all building components
can interact to affect how air movement distributes
Pollutant Standard Index (PSI)—
Indicator of one or more pollutants that may
be used to inform the public about the potential
for adverse health effects from air pollution
in major cities.
the presence of a substance in the environment
that because of its chemical composition or
quantity prevents the functioning of natural
processes and produces undesirable environmental
and health effects.Under the Clean Water Act,
for example, the term has been defined as
the man-made or man-induced alteration of
the physical, biological, chemical, and radiological
integrity of water and other media.
1. Identifying areas, processes, and activities
which create excessive waste products or pollutants
in order to reduce or prevent them through,
alteration, or eliminating a process. Such
activities, consistent with the Pollution
Prevention Act of 1990, are conducted across
all EPA programs and can involve cooperative
efforts with such agencies as the Departments
of Agriculture and Energy. 2. EPA has initiated
a number of voluntary programs in which industrial,
or commercial or “partners” join
with EPA in promoting activities that conserve
energy, conserve and protect water supply,
reduce emissions or find ways of utilizing
them as energy resources, and reduce the waste
stream. Among these are— Agstar, to
reduce methane emissions through manure management.
Climate Wise, to lower industrial greenhouse-gas
emissions and energy costs. Coalbed Methane
Outreach, to boost methane recovery at coal
mines. Design for the Environment, to foster
including environmental considerations in
product design and processes. Energy Star
programs, to promote energy efficiency in
commercial and residential buildings, office
equipment, transformers, computers, office
equipment, and home appliances. Environmental
Accounting, to help businesses identify environmental
costs and factor them into management decision
making. Green Chemistry, to promote and recognize
cost-effective breakthroughs in chemistry
that prevent pollution. Green Lights, to spread
the use of energy-efficient lighting technologies.
Indoor Environments, to reduce risks from
indoor-air pollution. Landfill Methane Outreach,
to develop landfill gas-to-energy projects.
Natural Gas Star, to reduce methane emissions
from the natural gas industry. Ruminant Livestock
Methane, to reduce methane emissions from
ruminant livestock. Transportation Partners,
to reduce carbon dioxide emissions from the
transportation sector. Voluntary Aluminum
Industrial Partnership, to reduce perfluorocarbon
emissions from the primary aluminum industry.
WAVE, to promote efficient water use in the
lodging industry. Wastewi$e, to reduce business-generated
solid waste through prevention, reuse, and
A local effect produced in the tissue or organ
of first contact between a toxicant and the
Polonium— A radioactive
element that occurs in pitchblende and other
chemicals that help solids to clump during
Polymer— A natural or
synthetic chemical structure where two or
more like molecules are joined to form a more
complex molecular structure (e.g. polyethylene
Polyvinyl Chloride (PVC)—
A tough, environmentally indestructible plastic
that releases hydrochloric acid when burned.
Population— A group of
interbreeding organisms occupying a particular
space; the number of humans or other living
creatures in a designated area.
Population at Risk— A
population subgroup that is more likely to
be exposed to a chemical, or is more sensitive
to the chemical, than is the general population.
Porosity— Degree to which
soil, gravel, sediment, or rock is permeated
with pores or cavities through which water
or air can move.
of chlorine to plant effluent for disinfectant
purposes after the effluent has been treated.
Post-Closure— The time
period following the shutdown of a waste management
or manufacturing facility; for monitoring
purposes, often considered to be 30 years.
Recovered materials that are diverted from
municipal solid waste for the purpose of collection,
recycling, and disposition.
Use of materials generated from residential
and consumer waste for new or similar purposes;
e.g. converting wastepaper from offices into
corrugated boxes or newsprint.
Potable Water— Water
that is safe for drinking and cooking.
Potential Dose— The amount
of a compound contained in material swallowed,
breathed, or applied to the skin.
Potentially Responsible Party
(PRP)— Any individual or company—including
owners, operators, transporters or generators—potentially
responsible for, or contributing to a spill
or other contamination at a Superfund site.
Whenever possible, through administrative
and legal actions, EPA requires PRPs to clean
up hazardous sites they have contaminated.
Potentiation— The ability
of one chemical to increase the effect of
The surface to which water in an aquifer can
rise by hydrostatic pressure.
When information about potential risks is
incomplete, basing decisions about the best
ways to manage or reduce risks on a preference
for avoiding unnecessary health risks instead
of on unnecessary economic expenditures.
Materials generated in manufacturing and converting
processes such as manufacturing scrap and
trimmings and cuttings. Includes print overruns,
overissue publications, and obsolete inventories.
The time between the last pesticide application
and harvest of the treated crops.
addition of chlorine at the headworks of a
treatment plant prior to other treatment processes.
Done mainly for disinfection and control of
tastes, odors, and aquatic growths, and to
aid in coagulation and settling.
Precipitate— A substance
separated from a solution or suspension by
chemical or physical change.
of hazardous solids from liquid waste to permit
safe disposal; removal of particles from airborne
emissions as in rain (e.g. acid precipitation).
control device that collects particles from
an air stream.
Precursor— In photochemistry,
a compound antecedent to a pollutant. For
example, volatile organic compounds (VOCs)
and nitric oxides of nitrogen react in sunlight
to form ozone or other photochemical oxidants.
As such, VOCs and oxides of nitrogen are precursors.
The process of collecting and reviewing available
information about a known or suspected waste
site or release.
Prescriptive— Water rights
which are acquired by diverting water and
putting it to use in accordance with specified
procedures; e.g. filing a request with a state
agency to use unused water in a stream, river,
Pressed Wood Products—
Materials used in building and furniture construction
that are made from wood veneers, particles,
or fibers bonded together with an adhesive
under heat and pressure.
Pressure Sewers— A system
of pipes in which water, wastewater, or other
liquid is pumped to a higher elevation.
Pressure, Static— In
flowing air, the total pressure minus velocity
pressure, pushing equally in all directions.
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.
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
Prevention of Significant Deterioration
(PSD)— EPA program in which state and/or
federal permits are required in order to restrict
emissions from new or modified sources in
places where air quality already meets or
exceeds primary and secondary ambient air
Primacy— Having the primary
responsibility for administering and enforcing
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.
Primary Standards— National
ambient air quality standards designed to
protect human health with an adequate margin
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.
Principal Organic Hazardous
Constituents (POHCs)— Hazardous compounds
monitored during an incinerator’s trial
burn, selected for high concentration in the
waste feed and difficulty of combustion.
Prions— Microscopic particles
made of protein that can cause disease.
A doctrine of water law that allocates the
rights to use water on a first-come, first-served
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.
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
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.
Products of Incomplete Combustion
(PICs)— Organic compounds formed by
combustion. Usually generated in small amounts
and sometimes toxic, PICs are heat-altered
versions of the original material fed into
the incinerator (e.g. charcoal is a P.I.C.
from burning wood).
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.
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
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.
Publicly Owned Treatment Works
(POTWs)— A waste-treatment works owned
by a state, unit of local government, or Indian
tribe, usually designed to treat domestic
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.
decomposition of organic matter; associated
with anaerobic conditions.
Putrescible— Able to
rot quickly enough to cause odors and attract
of a chemical by extreme heat.