| (40) Innovative technology--A process, method, product,
or material not addressed in this chapter or a process specifically
identified as innovative by this chapter.
(41) Interceptor tank--A collection system unit that
receives raw wastewater, removes floatable and settleable solids,
stores the removed solids, and provides flow attenuation.
(42) Lift station--A structure that collects wastewater
and uses pumps to raise it to a higher elevation. The term lift station
applies to a structure in which the static head exceeds the frictional
head losses.
(43) Maintenance--The scheduled preventative care,
repair, or equivalent replacement of components or appurtenances of
a treatment unit or a collection system unit (e.g., replacing a pump
with an equivalent pump - not replacing an entire lift station, and
not replacing a pump in a lift station with a pump that will operate
at a different flow rate or pressure). Replacement must not cause
alteration, as defined in this chapter. Maintenance does not include
replacement of a treatment unit or a collection system unit.
(44) Membrane bioreactor system--An activated sludge
process that uses membrane filtration rather than clarification to
remove solids.
(45) Minimum grade effluent sewer--An alternative collection
system pipeline with a constant downward slope that transports effluent
from an interceptor tank by gravity flow.
(46) Multiple equivalent dwelling unit--Either:
(A) a group of two or more residences served by a common
service connection; or
(B) a commercial, industrial, institutional, or other
non-residential establishment that produces wastewater:
(i) in excess of 1,500 gallons per day; or
(ii) not comparable in composition to that discharged
by a single private residence.
(47) Non-conforming technology--Technology or a process
that does not conform to the design criteria of this chapter or a
technology or process specifically identified as non-conforming in
this chapter.
(48) Off-site component--A collection system component
that includes collection system pipes, force mains, pump stations,
lift stations, vacuum stations, and related appurtenances not located
at a wastewater treatment facility.
(49) On-site component--Alternative collection system
equipment placed on private property.
(50) Overflow--An unauthorized flow of untreated or
partially treated wastewater from a collection system or from a treatment
unit at a wastewater treatment facility.
(51) Owner--A person who owns a collection system or
a wastewater treatment facility or part of a collection system or
wastewater treatment facility. For the purposes of this chapter, "owner"
refers to the owner and to the owner's representatives, agents, and
designees (for example, an operator, an engineer, a staff member,
a contractor).
(52) Partially mixed aerated lagoon--A lagoon in which
oxygen is supplied mainly through mechanical or diffused aeration,
in which the aeration system is designed to allow solids to settle
out of suspension.
(53) Peak flow--The highest two-hour flow expected
under any operational conditions, including times of high rainfall,
based on a two-year, 24-hour storm or a prolonged period of wet weather.
(54) Plans--Construction drawings or other documents
that show details of the design of a project.
(55) Preliminary treatment--Removal of wastewater constituents
such as rags, sticks, floating material, and grit that may cause maintenance
or operational problems in subsequent treatment units.
(56) Pressure sewer--A collection system that is pressurized
by pumps at each service connection.
(57) Primary sedimentation unit--A treatment unit that
removes solids from the wastewater by physical settling before the
wastewater enters a unit that removes waste by biological conversion.
(58) Primary treatment--A physical treatment process,
other than preliminary treatment, that removes biologically available
wastewater constituents primarily by settling or floatation.
(59) Processing unit--A component of a wastewater treatment
facility that performs a basic step in preparing sludge for disposal
after the sludge has been separated from the wastewater (e.g., sludge
thickener, digester, sludge drying bed, belt press). Processing units
are considered a subset of treatment units for the purposes of this
chapter.
(60) Project--A construction, repair, alteration, or
rehabilitation of a collection system, a wastewater treatment facility,
or an associated component, beginning with design initiation and ending
with permanent decommissioning.
(61) Pump--A device that raises, transfers, or compresses
fluids by suction, pressure, or both.
(62) Rehabilitate--To repair a collection system using
a technology that is described in §217.56(c) of this title (relating
to Trenchless Pipe Installation) or using any other lining or coating
method.
(63) Re-rate--To change the design flow or design organic
loading of a treatment unit, without altering the unit, based on actual
performance data.
(64) Secondary treatment--The level of treatment defined
as secondary treatment in §309.1(b) of this title (relating to
Scope and Applicability).
(65) Sequencing batch reactor (SBR)--A fill and draw
activated sludge treatment system where secondary aeration and secondary
clarification processes are carried out sequentially in the same tank.
An SBR system has the following five steps that are carried out in
the following sequence:
(A) fill - the basin is filled with the influent;
(B) react - the influent in the basin is aerated;
(C) settle - the mixed liquor within the basin is settled
(clarification);
(D) draw - the basin is decanted; and
(E) idle - the sludge is removed from the basin.
(66) Sludge stabilization--The process of destroying
or inactivating pathogens in sludge and reducing volatile solids content.
(67) Small diameter effluent sewer--A collection system
that receives effluent from an interceptor tank and transports the
flow by gravity. A small diameter effluent sewer may include minimum
grade and variable grade effluent sewers.
(68) Specifications--Precise standards of performance
for construction work, materials, and manufactured products, which
make possible the expression of expected value when they are purchased
or contracted for and which provide means of determining their conformance
with expectations after they are purchased or constructed.
(69) Stabilization lagoon--A shallow lagoon used to
achieve secondary treatment through natural processes. In this chapter,
"stabilization lagoon" is synonymous with "stabilization pond," "oxidation
lagoon," and "oxidation pond."
(70) Subsurface flow wetland--A wetland system that
maintains the water level below the surface of the gravel or other
media placed in the wetland bed or cell.
(71) Summary transmittal letter--A letter submitted
to the executive director that provides basic information about a
project so that the executive director can determine whether to require
a full review of the project plans and specifications.
(72) Surcharge--The hydraulic overloading of a portion
of a gravity collection system. A surcharge causes wastewater to rise
within manholes and may cause an overflow.
(73) Totalizing meter--A water measuring device that
registers or accumulates total flow. The totalizing meter shall be
non-resettable.
(74) Treatment unit--A component of a wastewater treatment
facility that performs a basic step in the wastewater treatment process
(e.g., lift station, bar screen, aeration basin, clarifier, chlorine
contact chamber).
(75) Twenty-five-year, 24-hour rainfall event--The
maximum rainfall event with a probable recurrence interval of once
in 25 years, with a duration of 24 hours, as defined by the National
Weather Service in Technical Paper Number 40, Rainfall
Frequency Atlas of the United States, May 1961; or equivalent
regional or state rainfall information.
(76) Two-year, 24-hour rainfall event--The maximum
rainfall event with a probable recurrence interval of once in two
years, with a duration of 24 hours, as defined by the National Weather
Service in Technical Paper Number 40, Rainfall
Frequency Atlas of the United States, May 1961; or equivalent
regional or state rainfall information.
(77) Variable grade effluent sewer--A small diameter
gravity collection system that does not require a uniform gradient,
but will allow for both positive and negative gradients. A variable
grade effluent collection system may be used with septic tank effluent
pumps.
Cont'd... |
