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Completeness Checklist
Local agency staff can use the following checklist to help ensure that the noise element addresses all required issues. Please note
that use of this checklist is purely advisory, and only contains issues that are legally required by
Government Code section 65302
(f)
. Noise elements may address additional issues at the discretion of the local government. Because general plan formats may
vary, this checklist suggests identifying where the particular government code provision is satisfied.
Statutory Citation
Brief Description of Requirement
Gov. Code § 65302(f)(1)
(1) A noise element that shall identify and appraise noise problems in the community and shall analyze and
quantify, to the extent practicable, as determined
by the legislative body, current and projected noise levels for
all of the following sources:
(A) Highways and freeways.
Gov. Code § 65302 (f)(1)(B)
(B) Primary arterials and major local streets.
Gov. Code § 65302 (f)(1)(C)
(C) Passenger and freight online railroad operations and ground rapid transit systems.
Gov. Code §65302 (f)(1)(D)
(D) Commercial, general aviation, heliport, helistop, and
military airport operations, aircraft overflights, jet
engine test stands, and all other ground facilities and maintenance functions related to airport operation.
Gov. Code § 65302(f)(1)(E)
(E) Local industrial plants, including, but not limited to, railroad classification yards
Gov. Code § 65302 (f)(1)(F)
(F) Other ground stationary noise sources, including, but not limited to,
military installations,
identified by
local agencies as contributing to the community noise environment
Gov. Code § 65302(f)(2)
(2) Noise contours shall be shown for all of these sources and stated in terms of community noise
equivalent level (CNEL) or day-night average level (Ldn). The noise contours shall be prepared on the
basis of noise monitoring or following generally accepted noise modeling techniques for the various
sources identified in paragraphs (1) to (6), inclusive.
Gov. Code § 65302(f)(3)
(3) The noise contours shall be used as a guide for establishing a pattern of land uses in the land use element
that minimizes the exposure of community residents to excessive noise.
Gov. Code § 65302(f)(4)
(4) The noise element shall include implementation measures and possible solutions that address existing
and foreseeable noise problems, if any. The adopted noise element shall serve as a guideline for
compliance with the state’s noise insulation standards.
Required
Contents
The noise element should utilize the most accurate and up-to-date information available to reflect the noise environment,
stationary sources of noise, predicted levels of noise, and the impacts of noise on local residents. It should be as detailed as
necessary to describe the local situation and offer solutions to local noise issues. It must include the considerations of noise
levels from:
(A) Highways and freeways.
(B) Primary arterials and major local streets.
(C) Passenger and freight online railroad operations and ground rapid transit systems.
(D) Commercial, general aviation, heliport, helistop, and military airport operations, aircraft overflights, jet engine test stands,
and all other ground facilities and maintenance functions related to airport operation.
(E) Local industrial plants, including, but not limited to, railroad classification yards.
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(F) Other ground stationary noise sources, including, but not limited to, military installations, identified by local agencies as
contributing to the community noise environment.
The general plan’s noise element must show contours for these noise sources, to the extent practicable, in either Community
Noise Equivalent Levels (
CNEL
) or Day-Night Average Level (
Ldn
). These noise contours must be prepared using noise
monitoring or accepted noise-modeling techniques. The noise contours must be used as a guide to establish a pattern of land
uses in the land use element that minimizes the exposure of community residents to excessive noise (
Gov. Code § 65302 (f)
(2), (f)(3)
). The noise element must include implementation measures and possible solutions to existing and foreseeable noise
issues. Furthermore, the policies and standards must be sufficient to serve as a guideline for compliance with the state’s noise
insulation standards (
Gov. Code § 65302(f)(4)
).
The noise element should be used to guide decisions concerning land use and the location of new
roads and transit facilities
since these are common sources of excessive noise levels. Proposed land uses should be analyzed to ensure they are compatible
with existing uses in the surrounding area, especially residential developments and sensitive receptors, such as schools,
hospitals, and places of worship. Additionally, construction noise, especially in urban areas, can be mitigated with policies such
as limiting construction hours or days.
Definitions
Decibel, dB: A unit of measurement describing
the amplitude of sound, equal to 20 times the logarithm to the base 10 of the
ratio of the pressure of the sound measured to the reference pressure, which is 20 micropascals (20 micronewtons per square
meter).
A-Weighted Level: The sound level in decibels as measured on a sound level meter using the A-weighting filter network. The
A-weighting filter de-emphasizes the very low and very high frequency components of the sound in a manner similar to the
response of the human ear and gives good correlation with subjective reactions to noise.
L10: The A-weighted sound level that is exceeded ten percent of the sample time. Similarly, L50, L90, etc.
Leq: Equivalent energy level. The sound level corresponding to a steady-state sound level containing the same total energy as a time-
varying signal over a given sample period. Leq is typically computed over 1-, 8-, and 24-hour sample periods.
CNEL: Community Noise Equivalent Level. The average equivalent A-weighted sound level during a 24-hour day, obtained after
addition of five decibels to sound levels in the evening from 7 p.m. to 10 p.m. and after addition of 10 decibels to sound levels in
the night from 10 p.m. to 7 a.m.
Ldn: Day-Night Average Level. The average equivalent A-weighted sound level during a 24-hour day,
obtained after the addition
of 10 decibels to sound levels in the night after 10 p.m. and before 7 a.m. (Note: CNEL and Ldn represent daily levels of noise
exposure averaged on an annual or daily basis, while Leq represents the equivalent energy noise exposure for a shorter time
period, typically one hour.)