40910-40930
HEALTH AND SAFETY CODE
SECTION 40910-40930
40910. It is the intent of the Legislature in enacting this chapter
that districts shall endeavor to achieve and maintain state ambient
air quality standards for ozone, carbon monoxide, sulfur dioxide, and
nitrogen dioxide by the earliest practicable date. In developing
attainment plans and regulations to achieve this objective, districts
shall consider the full spectrum of emission sources and focus
particular attention on reducing the emissions from transportation
and areawide emission sources. Districts shall also consider the
cost-effectiveness of their air quality programs, rules, regulations,
and enforcement practices in addition to other relevant factors, and
shall strive to achieve the most efficient methods of air pollution
control. However, priority shall be placed upon expeditious progress
toward the goal of healthful air. It is also the intent of the
Legislature that redundant work shall be avoided.
40911. (a) Except as provided in subdivision (b), each district
which has been designated a nonattainment area for state ambient air
quality standards for ozone, carbon monoxide, sulfur dioxide, or
nitrogen dioxide shall prepare and submit a plan for attaining and
maintaining the standards to the state board not later than December
31, 1990.
(b) Notwithstanding subdivision (a), any district which is a
receptor or contributor of transported air pollutants, as determined
by the state board pursuant to subdivision (a) of Section 39610,
shall prepare and submit its plan to the state board not later than
June 30, 1991.
40912. The plans for districts responsible for or affected by air
pollutant transport shall provide for attainment and maintenance of
the state and federal standards in both the upwind and downwind
district. Each upwind district's plan shall contain, at a minimum,
all mitigation requirements established by the state board pursuant
to subdivision (b) of Section 39610. Each downwind district's plan
shall contain sufficient measures to reduce emissions originating in
the district below the level at which violations of state ambient air
quality standards would occur in the absence of the transport
contribution.
40913. (a) Each district plan shall be designed to achieve and
maintain the state standards by the earliest practicable date, as
determined by the district and subject to the approval of the state
board, and in consideration of all relevant factors, including, but
not limited to, the following:
(1) Present and projected maximum ambient pollutant concentration.
(2) Distribution and frequency of violations.
(3) Transport contributions.
(4) Projected emission increases based on industrial, vehicular,
or population growth.
(5) Emission inventory characteristics.
(6) Anticipated effectiveness of available and potential control
measures.
(7) Emission reductions occurring in, or expected to occur in, the
district.
(8) In districts where military bases have closed or are scheduled
for closure, the reuse plans for the closing base.
(b) Each district plan shall be based upon a determination by the
district board that the plan is a cost-effective strategy to achieve
attainment of the state standards by the earliest practicable date.
40914. (a) Each district plan shall be designed to achieve a
reduction in districtwide emissions of 5 percent or more per year for
each nonattainment pollutant or its precursors, averaged every
consecutive three-year period, unless an alternative measure of
progress is approved pursuant to Section 39607.
(b) A district may use an alternative emission reduction strategy
which achieves less than an average of 5 percent per year reduction
in districtwide emissions if the district demonstrates to the state
board, and the state board concurs in, either of the following:
(1) That the alternative emission reduction strategy is equal to
or more effective than districtwide emission reductions in improving
air quality.
(2) That despite the inclusion of every feasible measure in the
plan, and an expeditious adoption schedule, the district is unable to
achieve at least a 5-percent annual reduction in districtwide
emissions.
(c) For purposes of this section and Section 41503.1, for each
district that is designated nonattainment for a state ambient air
quality standard but is designated attainment for the federal air
quality standard for the same pollutant, reductions in emissions
shall be calculated with respect to the actual level of emissions
that exist in each district during 1990, as determined by the state
board. All reductions in emissions occurring after December 31, 1990,
including, but not limited to, reductions in emissions resulting
from measures adopted prior to December 31, 1990, shall be included
in this calculation. For each district that is designated
nonattainment for both state and federal ambient air quality
standards for a single pollutant, reductions in emissions shall be
calculated with respect to the actual level of emissions that exist
in each district during the baseline year used in the state
implementation plan required by the federal Clean Air Act. All
reductions in emissions occurring after December 31 of the baseline
year, including, but not necessarily limited to, reductions in
emissions resulting from measures adopted prior to December 31 of the
baseline year, shall be included in this calculation.
40915. Each district plan shall contain contingency measures to be
implemented upon a finding by the state board, pursuant to Section
41503.3, that the district is failing to achieve interim goals or
maintain adequate progress toward attainment. Any regulations
necessary to implement the contingency measures shall be adopted by
the district within 180 days following the state board's
determination of inadequate progress.
40916. (a) The state board shall make technical assistance
available to a district, at the district's request, to support
attainment planning and air pollutant transport planning and
associated analyses. If the state board lacks sufficient resources to
make technical assistance available to each district that requests
assistance, the state board shall give priority to those districts
that have limited financial or technical capabilities.
(b) The state board shall develop guidelines for use by the
districts to prepare emission inventories, develop monitoring
networks, and develop methods for the validation of air quality
models.
(c) The state board shall develop and periodically update
guidelines for use by the districts to establish equivalent emission
reductions for mobile source emission control strategies and
transportation control measures.
(d) (1) The state board may recommend a suggested control measure
for adoption by a district to meet the requirements of the district's
plan adopted pursuant to this chapter for any architectural paint or
coating, if the state board determines all of the following:
(A) The control measure will achieve a feasible reduction in
volatile organic compounds emitted by the architectural paint or
coating. For purposes of this paragraph, "feasible reduction in
volatile organic compounds emitted" means an emission limitation that
is achievable, taking into account environmental, energy, and
economic impacts.
(B) Adequate data exist to establish that the control measure is
necessary to attain state and federal ambient air quality standards.
(C) The control measure is commercially and technologically
feasible and necessary.
(2) Nothing in this subdivision shall limit or affect the ability
of a district to adopt or enforce rules related to architectural
paint or coatings. Every rule adopted by a district regarding
architectural paint or coatings shall be adopted by the governing
board of the district in accordance with existing law, and shall
include at least one public workshop.
40917. Two or more districts within the same air basin shall
cooperate to the extent reasonable and appropriate in developing plan
elements of mutual concern. These elements may include, but are not
limited to, emission inventories, air quality models, and growth
projections.
40918. (a) Each district with moderate air pollution shall, to the
extent necessary to meet the requirements of the plan developed
pursuant to Section 40913, include the following measures in its
attainment plan:
(1) A stationary source control program designed to achieve no net
increase in emissions of nonattainment pollutants or their
precursors from new or modified stationary sources which emit or have
the potential to emit 25 tons per year or more of nonattainment
pollutants or their precursors. The program shall require the use of
best available control technology for any new or modified stationary
source which has the potential to emit 25 pounds per day or more of
any nonattainment pollutant or its precursors.
(2) The use of reasonably available control technology for all
existing stationary sources, except that stationary sources permitted
to emit five tons or more per day or 250 tons or more per year shall
be equipped with the best available retrofit control technology.
(3) Reasonably available transportation control measures
sufficient to substantially reduce the rate of increase in passenger
vehicle trips and miles traveled per trip if the district contains an
urbanized area with a population of 50,000 or more.
(4) Provisions to develop areawide source and indirect source
control programs.
(5) Provisions to develop and maintain an emissions inventory
system to enable analysis and progress reporting and a commitment to
develop other analytical techniques to carry out its responsibilities
pursuant to subdivision (b) of Section 40924.
(6) Provisions for public education programs to promote actions to
reduce emissions from transportation and areawide sources.
(b) Any district with moderate air pollution that is not below the
pollutant concentrations for a moderate classification pursuant to
Sections 40921 and 40921.5 by December 31, 1997, shall comply with
Section 40919 if the state board demonstrates that the additional
requirements of Section 40919 will substantially expedite the
district's attainment of the state ambient air quality standards. Any
actions taken by the state board pursuant to this subdivision are
subject to Section 41503.4.
40918.5. (a) Notwithstanding Sections 40918, 40919, and 40920, a
district that does not have extreme air pollution may elect to not
include a no-net-increase permitting program in its attainment plan
if all of the following actions are taken:
(1) The governing board of the district finds, at a public
hearing, that the no-net-increase permitting program is not necessary
to achieve and maintain the state ambient air quality standards by
the earliest practicable date.
(2) Prior to making the finding specified in paragraph (1), the
governing board does both of the following:
(A) Reviews an estimate of the growth in emissions, if any, that
is likely to occur as a result of the elimination of a
no-net-increase permitting program.
(B) Complies with Section 40914 either by having adopted, or
having scheduled for adoption, all feasible measures to achieve and
maintain state ambient air quality standards, or by the use of an
alternative emission reduction strategy.
(3) The governing board of the district submits its finding to the
state board, and, within 60 days from the date of the submittal of
the finding, the state board makes a determination based on
quantifiable and substantial evidence that a no-net-increase
permitting program is not necessary to comply with the mitigation
requirements established pursuant to Section 39610 and that the
no-net-increase permitting program is not necessary to achieve and
maintain the state ambient air quality standards by the earliest
practicable date. If the state board does not make any determination
within that 60-day period, and the district does not agree to an
extension of that time period, the district may make the election
authorized by this subdivision.
(b) Nothing in this section shall relieve a district from the
obligation to require the use of the best available control
technology pursuant to Section 40918, 40919, or 40920.
40918.6. Following the implementation of Section 40918.5, both of
the following shall occur:
(1) The district governing board's finding pursuant to paragraph
(1) of subdivision (a) of Section 40918.5 shall, by operation of law,
become part of the district's attainment plan.
(2) The state board shall, during any subsequent review of the
district's attainment plan pursuant to subdivision (a) of Section
41500, determine based on quantifiable and substantial evidence
whether or not a no-net-increase permitting program is necessary to
comply with mitigation requirements established pursuant to Section
39610 or to achieve and maintain state ambient air quality standards
by the earliest practicable date. If the state board determines that
a no-net-increase permitting program is necessary to comply with
those requirements, the district shall then adopt and implement a
no-net-increase permitting program pursuant to Section 40918, 40919,
or 40920.
40918.7. (a) Emission reduction offset credits created pursuant to
subdivision (p) of Section 41865 shall be approved for use by a
stationary source in another district if all of the following
conditions are met:
(1) The district containing the source providing the offset
credits does not have a no-net-increase permitting program in its
attainment plan.
(2) The district where the offset credits are to be used is
designated as having moderate air pollution.
(3) The district where the offset credits are to be used is
located within the same air basin as, or within an air basin that is
contiguous to, the air basin in which the district containing the
source providing the offsets is located.
(4) The site where the offset credits will be used is located
within 200 linear air miles from the source providing the offset
credits.
(b) If all of the conditions specified in subdivision (a) are met,
the district receiving the offset credit shall do both of the
following:
(1) Determine the type and quantity of the emission reductions to
be credited.
(2) Adopt a rule or regulation to discount the emission reductions
credited to the stationary source. The discount shall not be less
than the emission reduction for offsets from comparable sources
located within the district boundaries.
40919. (a) Each district with serious air pollution shall, to the
extent necessary to meet the requirements of the plan adopted
pursuant to Section 40913, include the following measures in its
attainment plan:
(1) All measures required for moderate nonattainment areas, as
specified in Section 40918.
(2) A stationary source control program designed to achieve no net
increase in emissions of nonattainment pollutants or their
precursors from all new or modified stationary sources which emit, or
have the potential to emit, 15 tons or more per year. The program
shall require the use of best available control technology for any
new or modified stationary source which has the potential to emit 10
pounds per day or more of any nonattainment pollutant or its
precursors.
(3) The use of the best available retrofit control technology, as
defined in Section 40406, for all existing permitted stationary
sources.
(4) Measures to achieve the use of a significant number of
low-emission motor vehicles by operators of motor vehicle fleets.
(b) Any district with serious air pollution that has not met the
criteria for a moderate classification by December 31, 1997, shall
comply with Section 40920 if the state board demonstrates that the
additional requirements of Section 40920 will substantially expedite
the district's attainment of the state ambient air quality standards.
Any actions taken by the state board pursuant to this subdivision
are subject to Section 41503.4.
40920. Each district with severe air pollution shall, to the extent
necessary to meet the requirements of Section 40913, include the
following measures in its attainment plan:
(a) All measures required for moderate and serious nonattainment
areas, as specified in Sections 40918 and 40919.
(b) A stationary source control program designed to achieve no net
increase in emissions of nonattainment pollutants or their
precursors from all new or modified stationary sources which emit, or
have the potential to emit, 10 tons or more per year.
(c) Measures sufficient to reduce overall population exposure to
ambient pollutant levels in excess of the standard by at least 25
percent by December 31, 1994, 40 percent by December 31, 1997, and 50
percent by December 31, 2000, based on average per capita exposure
and the severity of the exposure, so as to minimize health impacts,
using the average level of exposure experienced during 1986 through
1988 as the baseline.
40920.5. Each district with extreme air pollution shall, to the
extent necessary to meet the requirements of the plan developed
pursuant to Section 40913, include the following measures in its
attainment plan:
(a) All measures required for moderate, serious, and severe areas.
(b) A stationary source control program designed to achieve no net
increase in emissions from new or modified stationary sources of
nonattainment pollutants or their precursors.
(c) Any other feasible controls that can be implemented, or for
which implementation can begin, within 10 years of the adoption date
of the most recent air quality plan.
40920.6. (a) Prior to adopting rules or regulations to meet the
requirement for best available retrofit control technology pursuant
to Sections 40918, 40919, 40920, and 40920.5, or for a feasible
measure pursuant to Section 40914, districts shall, in addition to
other requirements of this division, do all of the following:
(1) Identify one or more potential control options which achieves
the emission reduction objectives for the regulation.
(2) Review the information developed to assess the
cost-effectiveness of the potential control option. For purposes of
this paragraph, "cost-effectiveness" means the cost, in dollars, of
the potential control option divided by emission reduction potential,
in tons, of the potential control option.
(3) Calculate the incremental cost-effectiveness for the potential
control options identified in paragraph (1). To determine the
incremental cost-effectiveness under this paragraph, the district
shall calculate the difference in the dollar costs divided by the
difference in the emission reduction potentials between each
progressively more stringent potential control option as compared to
the next less expensive control option.
(4) Consider, and review in a public meeting, all of the
following:
(A) The effectiveness of the proposed control option in meeting
the requirements of this chapter and the requirements adopted by the
state board pursuant to subdivision (b) of Section 39610.
(B) The cost-effectiveness of each potential control option as
assessed pursuant to paragraph (2).
(C) The incremental cost-effectiveness between the potential
control options as calculated pursuant to paragraph (3).
(5) Make findings at the public hearing at which the regulation is
adopted stating the reasons for the district's adoption of the
proposed control option or options.
(b) A district may establish its own best available retrofit
control technology requirement based upon consideration of the
factors specified in subdivision (a) and Section 40406 if the
requirement complies with subdivision (d) of Section 40001 and is
consistent with this chapter, other state law, and federal law,
including, but not limited to, the applicable state implementation
plan.
(c) A district shall allow the retirement of marketable emission
reduction credits under a program which complies with all of the
requirements of Section 39616, or emission reduction credits which
meet all of the requirements of state and federal law, including, but
not limited to, the requirements that those emission reduction
credits be permanent, enforceable, quantifiable, and surplus, in lieu
of any requirement for best available retrofit control technology,
if the credit also complies with all district rules and regulations
affecting those credits.
(d) After a district has established the cost-effectiveness, in a
dollar amount, for any rule or regulation adopted pursuant to this
section or Section 40406, 40703, 40914, 40918, 40919, 40920, 40920.6,
or 40922, the district, consistent with subdivision (d) of Section
40001, shall allow alternative means of producing equivalent emission
reductions at an equal or lesser dollar amount per ton reduced,
including the use of emission reduction credits, for any stationary
source that has a demonstrated compliance cost exceeding that
established dollar amount.
40921. For the purposes of Sections 40918, 40919, 40920, and
40920.5, the designation of a district's air pollution as "moderate,"
"serious," "severe," or "extreme" for an area which is a receptor of
transported air pollutants shall be based on violations of state
ambient air quality standards which would occur without regard to the
transport contribution.
40921.5. (a) For purposes of classifying ozone nonattainment areas
pursuant to Sections 40918, 40919, 40920, and 40920.5, the terms
moderate, serious, severe, and extreme shall be defined as follows:
greater than 0.09 to not
more
(1) Moderate ......... than 0.12 parts per
million,
inclusive.
0.13 to 0.15 parts per
(2) Serious .......... million,
inclusive.
0.16 to 0.20 parts per
(3) Severe ........... million,
inclusive.
(4) Extreme .......... greater than 0.20 parts
per million.
(b) For the purposes of classifying carbon monoxide nonattainment
areas under Sections 40918 and 40919, the terms moderate and serious
shall be defined as follows:
greater than 9.0 to 12.7
(1) Moderate ......... parts
per million, inclusive.
(2) Serious .......... greater than 12.7 parts
per million.
(c) The state board shall determine the ambient concentration of
each nonattainment area consistent with the designation criteria
established pursuant to subdivision (e) of Section 39607.
Classifications for ozone shall be based upon the calendar years 1989
to 1991, inclusive. Classifications for carbon monoxide shall be
based upon the 1989-90 and 1990-91 winter seasons.
40922. (a) Each plan prepared pursuant to this chapter shall
include an assessment of the cost effectiveness of available and
proposed control measures and shall contain a list which ranks the
control measures from the least cost-effective to the most
cost-effective.
(b) In developing an adoption and implementation schedule for a
specific control measure, the district shall consider the relative
cost effectiveness of the measure, as determined under subdivision
(a), as well as other factors including, but not limited to,
technological feasibility, total emission reduction potential, the
rate of reduction, public acceptability, and enforceability.
40923. (a) Upon the state board's approval of a district's
attainment plan, and each January 1 thereafter, the district shall
publish a list of regulatory measures scheduled or tentatively
scheduled for consideration during the following year. The district
shall not propose a regulatory measure for consideration during any
year that is not contained in the district's most recently published
list of proposed regulatory measures unless earlier consideration is
necessary to satisfy federal requirements, to abate a substantial
endangerment to public health or welfare, or to comply with Section
39666 or 40915.
(b) Subdivision (a) does not apply to any modification of existing
rules that the district finds and determines is necessary to do
either of the following:
(1) Preserve the original intent of the rules, as stated upon
their adoption.
(2) Increase opportunities for alternative compliance methodology
pursuant to subdivision (d) of Section 40001.
40924. (a) On or before December 31 of each year following the
state board's approval of a district's attainment plan, the district
shall prepare and submit a report to the state board summarizing its
progress in meeting the schedules for developing, adopting, and
implementing the air pollution control measures contained in the
district's plan. Those annual reports shall contain, at a minimum,
the proposed and actual dates for the adoption and implementation of
each measure.
(b) On or before December 31, 1994, and once every three years
thereafter, the district shall assess its progress toward attainment
of the state ambient air quality standards. Each triennial assessment
shall be incorporated into the district's triennial plan revision
prepared pursuant to Section 40925. Each triennial assessment shall
contain, at a minimum, both of the following:
(1) The extent of air quality improvement achieved during the
preceding three years, based upon ambient pollutant measurements,
best available modeling techniques, and air quality indicators
identified by the state board for that purpose under subdivision (f)
of Section 39607.
(2) The expected and revised emission reductions for each measure
scheduled for adoption in the preceding three-year period.
40925. (a) On or before December 31, 1994, and at least once every
three years thereafter, every district shall review and revise its
attainment plan to correct for deficiencies in meeting the interim
measures of progress incorporated into the plan pursuant to Section
40914, and to incorporate new data or projections into the plan,
including, but not limited to, the quantity of emission reductions
expected from the control measures adopted in the preceding
three-year period and the dates that those emission reductions will
be achieved, and the rates of population-related, industry-related,
and vehicle-related emissions growth actually experienced in the
district and projected for the future. This data shall be compared to
the rate of emission reductions and growth projected in the previous
triennial plan revision. Upon adoption of each triennial plan
revision at a public hearing, the district board shall submit the
revision to the state board.
(b) A district may modify the emission reduction strategy or
alternative measure of progress for subsequent years based on this
assessment if the district demonstrates to the state board, and the
state board finds, that the modified strategy is at least as
effective in improving air quality as the strategy which is being
replaced.
(c) Each district which cannot demonstrate attainment by December
31, 1999, shall prepare and submit a comprehensive update of its plan
to the state board not later than December 31, 1997, unless the
state board determines, by not later than February 1, 1997, that a
comprehensive plan update is unnecessary. The revised plan shall
include an interim air quality improvement goal or an equivalent
emission reduction strategy, subject to review and approval by the
state board, to be achieved in the subsequent five-year period.
40925.3. (a) The state board shall publish on a quarterly basis, or
on a more frequent basis if determined necessary by the state board,
a list of each district's rules or rule amendments that are
submitted during that quarter to the United States Environmental
Protection Agency as revisions to the state implementation plan. The
list shall include the following dates and information, if available:
(1) The date the district adopted the revision.
(2) The date the revision was submitted to the state board.
(3) The date the state board submitted the revision to the United
States Environmental Protection Agency.
(4) The date the United States Environmental Protection Agency
published notice of a proposed action on the revision in the Federal
Register and the nature of that proposed final action.
(5) The date the United States Environmental Protection Agency
took final action of the revision and the nature of that final
action.
(b) The state board may remove a revision from the list published
pursuant to subdivision (a) 30 days after the United States
Environmental Protection Agency takes final action on the revision.
(c) For the purposes of this section, "publish" means to post the
information on the state board's Internet website, or to make the
information available to any party in writing upon request.
40925.5. (a) A district which is nonattainment for the state ozone
standard shall be designated "nonattainment-transitional" by
operation of law if, during a single calendar year, the state
standard is not exceeded more than three times at any monitoring
location within the district.
(b) Any district which is designated nonattainment-transitional
under subdivision (a) shall review its plan for attaining the state
ozone standard and shall determine whether the stationary source
control measures scheduled for adoption or implementation within the
next three years by the district are needed to accomplish expeditious
attainment or to maintain the state standard following the projected
attainment date. In making that determination, the district shall
consider air quality trends, the effect of the state's adopted and
proposed motor vehicle and area source control programs, turnover of
the vehicle fleet, the impact of measures previously adopted by the
district, the state board, and the Environmental Protection Agency
which are in the process of being implemented, and other significant
factors influencing emissions trends.
(c) If a nonattainment-transitional district determines that one
or more of the stationary source control measures scheduled for
adoption or implementation within the next three years are no longer
necessary to accomplish expeditious attainment or to maintain the
state standard, the district shall shift those measures to the
contingency category.
(d) If a nonattainment-transitional district determines that
delaying one or more stationary source control measures will not
retard the achievement of the state ozone standard, it may delay that
measure.
(e) Subdivisions (c) and (d) shall not apply to any stationary
source control measures required by Section 39610. In addition,
subdivisions (c) and (d) shall be suspended at any time that the
district ceases to qualify for a nonattainment-transitional
designation under subdivision (a).
(f) Actions of any district pursuant to this section are effective
immediately. The state board may disapprove any action of the
district pursuant to this section within 90 days of the action. The
state board shall not disapprove district actions pursuant to this
section unless it finds that the actions will delay expeditious
attainment of the state ozone standard. Actions taken by the state
board pursuant to this subdivision are subject to Section 41503.4.
(g) Actions of any district pursuant to subdivisions (c) or (d)
shall be reviewed by the district in connection with its next review
and revision of its attainment plan pursuant to Section 40925.
40926. Nothing in this chapter restricts the authority of the state
board or a district to adopt regulations to control suspended
particulate matter, visibility reducing particles, lead, hydrogen
sulfide, or sulfates, or their precursors.
40930. (a) Each district that has adopted a plan pursuant to this
chapter shall, on or before January 31 of each year, prepare and
submit to the state board a report identifying the number of days
during the preceding calendar year that air quality in the district
violated each state ambient air quality standard for which the
district's status is nonattainment.
(b) For any pollutant for which the report indicates that the
applicable state ambient air quality standard was not violated during
more than three days during the calendar year at any one or more
monitoring locations within the district, the district shall not
adopt any new or more stringent control measure until after
preparation, and approval by the district board, of an analysis that
does all of the following:
(1) Assesses the costs and benefits of all additional district,
state, and federal regulatory actions that would be necessary to
achieve attainment of the applicable state ambient air quality
standard, taking into account only the additional costs and benefits
attributable to achieving the state standard for the remaining three
or fewer days each year.
(2) Includes consideration of all of the socioeconomic impacts
specified in Section 40728.5.
(3) Identifies, if the district is an upwind district, the
benefits of the additional regulatory actions in the district on the
air quality in any downwind district, and identifies the costs
attributable to those regulatory actions.
(c) The state board shall review the district analyses prepared
pursuant to subdivision (b) to ensure expeditious progress towards
attainment in both the district that prepared the analysis and any
downwind district and to ensure that any resulting action of the
district that prepared the analysis does not adversely affect any
downwind district.