[Code of Federal Regulations]
[Title 40, Volume 3]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR52.128]
[Page 134-147]
TITLE 40--PROTECTION OF ENVIRONMENT
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS--Table of Contents
Subpart D--Arizona
Sec. 52.128 Rule for unpaved parking lots, unpaved roads and vacant lots.
(a) General. (1) Purpose. The purpose of this section is to limit
the emissions of particulate matter into the ambient air from human
activity on unpaved parking lots, unpaved roads and vacant lots.
(2) Applicability. The provisions of this section shall apply to
owners/operators of unpaved roads, unpaved parking lots and vacant lots
and responsible parties for weed abatement on vacant lots in the Phoenix
PM-10 nonattainment area. This section does not apply to unpaved roads,
unpaved parking lots or vacant lots located on an industrial facility,
construction, or earth-moving site that has an approved permit issued by
Maricopa County Environmental Services Division under Rule 200, Section
305, Rule 210 or Rule 220 containing a Dust Control Plan approved under
Rule 310 covering all unpaved parking lots, unpaved roads and vacant
lots. This section does not apply to the two Indian Reservations (the
Salt River Pima-Maricopa Indian Community and the Fort McDowell Mojave-
Apache Indian Community) and a portion of a third reservation (the Gila
River Indian Community) in the Phoenix PM-10 nonattainment area. Nothing
in this definition shall preclude applicability of this section to
vacant lots with disturbed surface areas due to construction, earth-
moving, weed abatement or other dust generating operations which have
been terminated for over eight months.
(3) The test methods described in Appendix A of this section shall
be used when testing is necessary to determine whether a surface has
been stabilized as defined in paragraph (b)(16) of this section.
(b) Definitions. (1) Average daily trips (ADT)--The average number
of vehicles that cross a given surface during a specified 24-hour time
period as determined by the Institute of Transportation Engineers Trip
Generation Report (6th edition, 1997) or tube counts.
(2) Chemical/organic stabilizer--Any non-toxic chemical or organic
dust suppressant other than water which meets any specifications,
criteria, or tests required by any federal, state, or local water agency
and is not prohibited for use by any applicable law, rule or regulation.
(3) Disturbed surface area--Any portion of the earth's surface, or
materials placed thereon, which has been physically moved, uncovered,
destabilized, or otherwise modified from its undisturbed natural
condition, thereby increasing the potential for emission of fugitive
dust.
(4) Dust suppressants--Water, hygroscopic materials, solution of
water and chemical surfactant, foam, or non-toxic chemical/organic
stabilizers not prohibited for use by any applicable law, rule or
regulation, as a treatment material to reduce fugitive dust emissions.
(5) EPA--United States Environmental Protection Agency, Region IX,
75 Hawthorne Street, San Francisco, California 94105.
(6) Fugitive dust--The particulate matter entrained in the ambient
air which is caused from man-made and
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natural activities such as, but not limited to, movement of soil,
vehicles, equipment, blasting, and wind. This excludes particulate
matter emitted directly from the exhaust of motor vehicles and other
internal combustion engines, from portable brazing, soldering, or
welding equipment, and from piledrivers.
(7) Lot--A parcel of land identified on a final or parcel map
recorded in the office of the Maricopa County recorder with a separate
and distinct number or letter.
(8) Low use unpaved parking lot--A lot on which vehicles are parked
no more than thirty-five (35) days a year, excluding days where the
exemption in paragraph (c)(2) of this section applies.
(9) Motor vehicle--A self-propelled vehicle for use on the public
roads and highways of the State of Arizona and required to be registered
under the Arizona State Uniform Motor Vehicle Act, including any non-
motorized attachments, such as, but not limited to, trailers or other
conveyances which are connected to or propelled by the actual motorized
portion of the vehicle.
(10) Off-road motor vehicle--any wheeled vehicle which is used off
paved roadways and includes but is not limited to the following:
(i) Any motor cycle or motor-driven cycle;
(ii) Any motor vehicle commonly referred to as a sand buggy, dune
buggy, or all terrain vehicle.
(11) Owner/operator--any person who owns, leases, operates,
controls, maintains or supervises a fugitive dust source subject to the
requirements of this section.
(12) Paving--Applying asphalt, recycled asphalt, concrete, or
asphaltic concrete to a roadway surface.
(13) Phoenix PM-10 nonattainment area--such area as defined in 40
CFR 81.303, excluding Apache Junction.
(14) PM-10--Particulate matter with an aerodynamic diameter less
than or equal to a nominal 10 micrometers as measured by reference or
equivalent methods that meet the requirements specified for PM-10 in 40
CFR part 50, Appendix J.
(15) Reasonably available control measures (RACM)--Techniques used
to prevent the emission and/or airborne transport of fugitive dust and
dirt.
(16) Stabilized surface--(i) Any unpaved road or unpaved parking lot
surface where:
(A) Any fugitive dust plume emanating from vehicular movement does
not exceed 20 percent opacity as determined in section I.A of Appendix A
of this section; and
(B) Silt loading (weight of silt per unit area) is less than 0.33
ounces per square foot as determined by the test method in section I.B
of Appendix A of this section OR where silt loading is greater than or
equal to 0.33 ounces per square foot and silt content does not exceed
six (6) percent for unpaved road surfaces or eight (8) percent for
unpaved parking lot surfaces as determined by the test method in section
I.B of Appendix A of this section.
(ii) Any vacant lot surface with:
(A) A visible crust which is sufficient as determined in section
II.1 of Appendix A of this section;
(B) A threshold friction velocity (TFV), corrected for non-erodible
elements, of 100 cm/second or higher as determined in section II.2 of
Appendix A of this section;
(C) Flat vegetation cover equal to at least 50 percent as determined
in section II.3 of Appendix A of this section;
(D) Standing vegetation cover equal to or greater than 30 percent as
determined in section II.4 of Appendix A of this section; or
(E) Standing vegetation cover equal to or greater than 10 percent as
determined in section II.4 of Appendix A of this section where threshold
friction velocity, corrected for non-erodible elements, as determined in
section II.2 of Appendix A of this section is equal to or greater than
43 cm/second.
(17) Unpaved parking lot--A privately or publicly owned or operated
area utilized for parking vehicles that is not paved and is not a Low
use unpaved parking lot.
(18) Unpaved road--Any road, equipment path or driveway used by
motor vehicles or off-road motor vehicles that is not paved which is
open to public access and owned/operated by any federal, state, county,
municipal or other governmental or quasi-governmental agencies.
[[Page 136]]
(19) Urban or suburban open area--An unsubdivided or undeveloped
tract of land adjoining a residential, industrial or commercial area,
located on public or private property.
(20) Vacant lot--A subdivided residential, industrial,
institutional, governmental or commercial lot which contains no approved
or permitted buildings or structures of a temporary or permanent nature.
(c) Exemptions. The following requirements in paragraph (d) of this
section do not apply:
(1) In paragraphs (d)(1), (d)(2) and (d)(4)(iii) of this section:
Any unpaved parking lot or vacant lot 5,000 square feet or less.
(2) In paragraphs (d)(1) and (d)(2) of this section: Any unpaved
parking lot on any day in which ten (10) or fewer vehicles enter.
(3) In paragraphs (d)(4)(i) and (d)(4)(ii) of this section: Any
vacant lot with less than 0.50 acre (21,780 square feet) of disturbed
surface area(s).
(4) In paragraph (d) of this section: Non-routine or emergency
maintenance of flood control channels and water retention basins.
(5) In paragraph (d) of this section: Vehicle test and development
facilities and operations when dust is required to test and validate
design integrity, product quality and/or commercial acceptance. Such
facilities and operations shall be exempted from the provisions of this
section only if such testing is not feasible within enclosed facilities.
(6) In paragraph (d)(4)(i) of this section: Weed abatement
operations performed on any vacant lot or property under the order of a
governing agency for the control of a potential fire hazard or otherwise
unhealthy condition provided that mowing, cutting, or another similar
process is used to maintain weed stubble at least three (3) inches above
the soil surface. This includes the application of herbicides provided
that the clean-up of any debris does not disturb the soil surface.
(7) In paragraph (d)(4)(i) of this section: Weed abatement
operations that receive an approved Earth Moving permit under Maricopa
County Rule 200, Section 305 (adopted 11/15/93).
(d) Requirements. (1) Unpaved parking lots. Any owners/operators of
an unpaved parking lot shall implement one of the following RACM on any
surface area(s) of the lot on which vehicles enter and park.
(i) Pave; or
(ii) Apply chemical/organic stabilizers in sufficient concentration
and frequency to maintain a stabilized surface; or
(iii) Apply and maintain surface gravel uniformly such that the
surface is stabilized; or
(iv) Apply and maintain an alternative control measure such that the
surface is stabilized, provided that the alternative measure is not
prohibited under paragraph (b)(2) or (b)(4) of this section.
(2) Any owners/operators of a low use unpaved parking lot as defined
in paragraph (b)(8) of this section shall implement one of the RACM
under paragraph (d)(1) of this section on any day(s) in which over 100
vehicles enter the lot, such that the surface area(s) on which vehicles
enter and park is/are stabilized throughout the duration of time that
vehicles are parked.
(3) Unpaved roads. Any owners/operators of existing unpaved roads
with ADT volumes of 250 vehicles or greater shall implement one of the
following RACM along the entire surface of the road or road segment that
is located within the Phoenix non-attainment area by June 10, 2000:
(i) Pave; or
(ii) Apply chemical/organic stabilizers in sufficient concentration
and frequency to maintain a stabilized surface; or
(iii) Apply and maintain surface gravel uniformly such that the
surface is stabilized; or
(iv) Apply and maintain an alternative control measure such that the
surface is stabilized, provided that the alternative measure is not
prohibited under paragraph (b)(2) or (b)(4) of this section.
(4) Vacant lots. The following provisions shall be implemented as
applicable.
(i) Weed abatement. No person shall remove vegetation from any
vacant lot by blading, disking, plowing under or
[[Page 137]]
any other means without implementing all of the following RACM to
prevent or minimize fugitive dust.
(A) Apply a dust suppressant(s) to the total surface area subject to
disturbance immediately prior to or during the weed abatement.
(B) Prevent or eliminate material track-out onto paved surfaces and
access points adjoining paved surfaces.
(C) Apply a dust suppressant(s), gravel, compaction or alternative
control measure immediately following weed abatement to the entire
disturbed surface area such that the surface is stabilized.
(ii) Disturbed surfaces. Any owners/operators of an urban or
suburban open area or vacant lot of which any portion has a disturbed
surface area(s) that remain(s) unoccupied, unused, vacant or undeveloped
for more than fifteen (15) calendar days shall implement one of the
following RACM within sixty (60) calendar days following the
disturbance.
(A) Establish ground cover vegetation on all disturbed surface areas
in sufficient quantity to maintain a stabilized surface; or
(B) Apply a dust suppressant(s) to all disturbed surface areas in
sufficient quantity and frequency to maintain a stabilized surface; or
(C) Restore to a natural state, i.e. as existing in or produced by
nature without cultivation or artificial influence, such that all
disturbed surface areas are stabilized; or
(D) Apply and maintain surface gravel uniformly such that all
disturbed surface areas are stabilized; or
(E) Apply and maintain an alternative control measure such that the
surface is stabilized, provided that the alternative measure is not
prohibited under paragraph (b)(2) or (b)(4) of this section.
(iii) Motor vehicle disturbances. Any owners/operators of an urban
or suburban open area or vacant lot of which any portion has a disturbed
surface area due to motor vehicle or off-road motor vehicle use or
parking, notwithstanding weed abatement operations or use or parking by
the owner(s), shall implement one of the following RACM within 60
calendar days following the initial determination of disturbance.
(A) Prevent motor vehicle and off-road motor vehicle trespass/
parking by applying fencing, shrubs, trees, barriers or other effective
measures; or
(B) Apply and maintain surface gravel or chemical/organic stabilizer
uniformly such that all disturbed surface areas are stabilized.
(5) Implementation date of RACM. All of the requirements in
paragraph (d) of this section shall be effective eight (8) months from
September 2, 1998. For requirements in paragraph (d)(4)(ii) and
(d)(4)(iii) of this section, RACM shall be implemented within eight (8)
months from September 2, 1998, or within 60 calendar days following the
disturbance, whichever is later.
(e) Monitoring and records. (1) Any owners/operators that are
subject to the provisions of this section shall compile and retain
records that provide evidence of control measure application, indicating
the type of treatment or measure, extent of coverage and date applied.
For control measures involving chemical/organic stabilization, records
shall also indicate the type of product applied, vendor name, label
instructions for approved usage, and the method, frequency,
concentration and quantity of application.
(2) Copies of control measure records and dust control plans along
with supporting documentation shall be retained for at least three
years.
(3) Agency surveys. (i) EPA or other appropriate entity shall
conduct a survey of the number and size (or length) of unpaved roads,
unpaved parking lots, and vacant lots subject to the provisions of this
section located within the Phoenix PM-10 nonattainment area beginning no
later than 365 days from September 2, 1998.
(ii) EPA or other appropriate entity shall conduct a survey at least
every three years within the Phoenix PM-10 nonattainment area beginning
no later than 365 days from September 2, 1998, which includes:
(A) An estimate of the percentage of unpaved roads, unpaved parking
lots, and vacant lots subject to this section to which RACM as required
in this section have been applied; and
(B) A description of the most frequently applied RACM and estimates
of their control effectiveness.
[[Page 138]]
Appendix A to Sec. 52.128--Test Methods To Determine Whether A Surface Is
Stabilized
I. Unpaved Roads and Unpaved Parking Lots
A. Opacity Observations
Conduct opacity observations in accordance with Reference Method 9
(40 CFR Part 60, appendix A) and Methods 203A and 203C of this appendix,
with opacity readings taken at five second observation intervals and two
consecutive readings per plume beginning with the first reading at zero
seconds, in accordance with Method 203C, sections 2.3.2. and 2.4.2 of
this appendix. Conduct visible opacity tests only on dry unpaved
surfaces (i.e. when the surface is not damp to the touch) and on days
when average wind speeds do not exceed 15 miles per hour (mph).
(i) Method 203A--Visual Determination of Opacity of Emissions From
Stationary Sources for Time-Arranged Regulations
Method 203A is virtually identical to EPA's Method 9 (40 CFR Part 60
Appendix A) except for the data-reduction procedures, which provide for
averaging times other than 6 minutes. That is, using Method 203A with a
6-minute averaging time would be the same as following EPA Method 9 (40
CFR Part 60, Appendix A). Additionally, Method 203A provides procedures
for fugitive dust applications. The certification procedures provided in
section 3 are virtually identical to Method 9 (40 CFR Part 60, Appendix
A) and are provided here, in full, for clarity and convenience.
1. Applicability and Principle
1.1 Applicability. This method is applicable for the determination
of the opacity of emissions from sources of visible emissions for time-
averaged regulations. A time-averaged regulation is any regulation that
requires averaging visible emission data to determine the opacity of
visible emissions over a specific time period.
1.2 Principle. The opacity of emissions from sources of visible
emissions is determined visually by an observer qualified according to
the procedures of section 3.
2. Procedures
An observer qualified in accordance with section 3 of this method
shall use the following procedures for visually determining the opacity
of emissions.
2.1 Procedures for Emissions from Stationary Sources. These
procedures are not applicable to this section.
2.2 Procedures for Fugitive Process Dust Emissions. These procedures
are applicable for the determination of the opacity of fugitive
emissions by a qualified observer. The qualified field observer should
do the following:
2.2.1 Position. Stand at a position at least 5 meters from the
fugitive dust source in order to provide a clear view of the emissions
with the sun oriented in the 140-degree sector to the back. Consistent
as much as possible with maintaining the above requirements, make
opacity observations from a position such that the line of vision is
approximately perpendicular to the plume and wind direction. As much as
possible, if multiple plumes are involved, do not include more than one
plume in the line of sight at one time.
2.2.2 Field Records. Record the name of the plant or site, fugitive
source location, source type [pile, stack industrial process unit,
incinerator, open burning operation activity, material handling
(transfer, loading, sorting, etc.)], method of control used, if any,
observer's name, certification data and affiliation, and a sketch of the
observer's position relative to the fugitive source. Also, record the
time, estimated distance to the fugitive source location, approximate
wind direction, estimated wind speed, description of the sky condition
(presence and color of clouds), observer's position relative to the
fugitive source, and color of the plume and type of background on the
visible emission observation form when opacity readings are initiated
and completed.
2.2.3 Observations. Make opacity observations, to the extent
possible, using a contrasting background that is perpendicular to the
line of vision. For roads, storage piles, and parking lots, make opacity
observations approximately 1 meter above the surface from which the
plume is generated. For other fugitive sources, make opacity
observations at the point of greatest opacity in that portion of the
plume where condensed water vapor is not present. For intermittent
sources, the initial observation should begin immediately after a plume
has been created above the surface involved. Do not look continuously at
the plume but, instead, observe the plume momentarily at 15-second
intervals.
2.3 Recording Observations. Record the opacity observations to the
nearest 5 percent every 15 seconds on an observational record sheet.
Each momentary observation recorded represents the average opacity of
emissions for a 15-second period.
2.4 Data Reduction for Time-Averaged Regulations. A set of
observations is composed of an appropriate number of consecutive
observations determined by the averaging time specified. Divide the
recorded observations into sets of appropriate time lengths for the
specified averaging time. Sets must consist of consecutive observations;
however, observations immediately preceding and following interrupted
observations shall be deemed consecutive. Sets need not be consecutive
in
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time and in no case shall two sets overlap, resulting in multiple
violations. For each set of observations, calculate the appropriate
average opacity.
3. Qualification and Testing
3.1 Certification Requirements. To receive certification as a
qualified observer, a candidate must be tested and demonstrate the
ability to assign opacity readings in 5 percent increments to 25
different black plumes and 25 different white plumes, with an error not
to exceed 15 percent opacity on any one reading and an average error not
to exceed 7.5 percent opacity in each category. Candidates shall be
tested according to the procedures described in paragraph 3.2. Any smoke
generator used pursuant to paragraph 3.2 shall be equipped with a smoke
meter which meets the requirements of paragraph 3.3. Certification tests
that do not meet the requirements of paragraphs 3.2 and 3.3 are not
valid.
The certification shall be valid for a period of 6 months, and after
each 6-month period, the qualification procedures must be repeated by an
observer in order to retain certification.
3.2 Certification Procedure. The certification test consists of
showing the candidate a complete run of 50 plumes, 25 black plumes and
25 white plumes, generated by a smoke generator. Plumes shall be
presented in random order within each set of 25 black and 25 white
plumes. The candidate assigns an opacity value to each plume and records
the observation on a suitable form. At the completion of each run of 50
readings, the score of the candidate is determined. If a candidate fails
to qualify, the complete run of 50 readings must be repeated in any
retest. The smoke test may be administered as part of a smoke school or
training program, and may be preceded by training or familiarization
runs of the smoke generator during which candidates are shown black and
white plumes of known opacity.
3.3 Smoke Generator Specifications. Any smoke generator used for the
purpose of paragraph 3.2 shall be equipped with a smoke meter installed
to measure opacity across the diameter of the smoke generator stack. The
smoke meter output shall display in-stack opacity, based upon a path
length equal to the stack exit diameter on a full 0 to 100 percent chart
recorder scale. The smoke meter optical design and performance shall
meet the specifications shown in Table A. The smoke meter shall be
calibrated as prescribed in paragraph 3.3.1 prior to conducting each
smoke reading test. At the completion of each test, the zero and span
drift, shall be checked, and if the drift exceeds 1 percent opacity,
the condition shall be corrected prior to conducting any subsequent test
runs. The smoke meter shall be demonstrated at the time of installation
to meet the specifications listed in Table A. This demonstration shall
be repeated following any subsequent repair or replacement of the
photocell or associated electronic circuitry including the chart
recorder or output meter, or every 6 months, whichever occurs first.
3.3.1 Calibration. The smoke meter is calibrated after allowing a
minimum of 30 minutes warm-up by alternately producing simulated opacity
of 0 percent and 100 percent. When stable response at 0 percent or 100
percent is noted, the smoke meter is adjusted to produce an output of 0
percent or 100 percent, as appropriate. This calibration shall be
repeated until stable 0 percent and 100 percent readings are produced
without adjustment. Simulated 0 percent and 100 percent opacity values
may be produced by alternately switching the power to the light source
on and off while the smoke generator is not producing smoke.
3.3.2 Smoke Meter Evaluation. The smoke meter design and performance
are to be evaluated as follows:
3.3.2.1 Light Source. Verify from manufacturer's data and from
voltage measurements made at the lamp, as installed, that the lamp is
operated within 5 percent of the nominal rated voltage.
3.3.2.2 Spectral Response of Photocell. Verify from manufacturer's
data that the photocell has a photopic response; i.e., the spectral
sensitivity of the cell shall closely approximate the standard spectral-
luminosity curve for photopic vision which is referenced in (b) of Table
A.
3.3.2.3 Angle of View. Check construction geometry to ensure that
the total angle of view of the smoke plume, as seen by the photocell,
does not exceed 15 degrees. Calculate the total angle of view as
follows:
[phis]v = 2 tan-1 d/2L
Where:
[phis]v = total angle of view;
d = the photocell diameter + the diameter of the limiting aperture; and
L = distance from the photocell to the limiting aperture.
The limiting aperture is the point in the path between the photocell
and the smoke plume where the angle of view is most restricted. In smoke
generator smoke meters, this is normally an orifice plate.
3.3.2.4 Angle of Projection. Check construction geometry to ensure
that the total angle of projection of the lamp on the smoke plume does
not exceed 15 degrees. Calculate the total angle of projection as
follows:
[phis]p = 2 tan-1 d/2L
Where:
[phis]p = total angle of projection;
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d = the sum of the length of the lamp filament + the diameter of the
limiting aperture; and
L = the distance from the lamp to the limiting aperture.
3.3.2.5 Calibration Error. Using neutral-density filters of known
opacity, check the error between the actual response and the theoretical
linear response of the smoke meter. This check is accomplished by first
calibrating the smoke meter according to 3.3.1 and then inserting a
series of three neutral-density filters of nominal opacity of 20, 50,
and 75 percent in the smoke meter path length. Use filters calibrated
within 2 percent. Care should be taken when inserting the filters to
prevent stray light from affecting the meter. Make a total of five
nonconsecutive readings for each filter. The maximum opacity error on
any one reading shall be 3 percent.
3.3.2.6 Zero and Span Drift. Determine the zero and span drift by
calibrating and operating the smoke generator in a normal manner over a
1-hour period. The drift is measured by checking the zero and span at
the end of this period.
3.3.2.7 Response Time. Determine the response time by producing the
series of five simulated 0 percent and 100 percent opacity values and
observing the time required to reach stable response. Opacity values of
0 percent and 100 percent may be simulated by alternately switching the
power to the light source off and on while the smoke generator is not
operating.
4. References
1. U.S. Environmental Protection Agency. Standards of Performance
for New Stationary Sources; appendix A; Method 9 for Visual
Determination of the Opacity of Emissions from Stationary Sources. Final
Rule. 39 FR 219. Washington, DC. U.S. Government Printing Office.
November 12, 1974.
2. Office of Air and Radiation. ``Quality Assurance Guideline for
Visible Emission Training Programs.'' EPA-600/S4-83-011. Quality
Assurance Division. Research Triangle Park, N.C. May 1982.
3. ``Method 9--Visible Determination of the Opacity of Emissions
from Stationary Sources.'' February 1984. Quality Assurance Handbook for
Air Pollution Measurement Systems. Volume III, section 3.1.2. Stationary
Source Specific Methods. EPA-600-4-77-027b. August 1977. Office of
Research and Development Publications, 26 West Clair Street, Cincinnati,
OH.
4. Office of Air Quality Planning and Standards. ``Opacity Error for
Averaging and Nonaveraging Data Reduction and Reporting Techniques.''
Final Report-SR-1-6-85. Emission Measurement Branch, Research Triangle
Park, N.C. June 1985.
5. The U.S. Environmental Protection Agency. Preparation, Adoption,
and Submittal of State Implementation Plans. Methods for Measurement of
PM10 Emissions from Stationary Sources. Final Rule. Federal
Register. Washington, DC. U.S. Government Printing Office. Volumes 55.
No. 74. pps. 14246-14279. April 17, 1990.
(ii) Method 203C--Visual Determination of Opacity of Emissions From
Stationary Sources for Instantaneous Limitation Regulations
Method 203C is virtually identical to EPA's Method 9 (40 CFR Part
60, Appendix A), except for the data-reduction procedures which have
been modified for application to instantaneous limitation regulations.
Additionally, Method 203C provides procedures for fugitive dust
applications which were unavailable when Method 9 was promulgated. The
certification procedures in section 3 are identical to Method 9. These
certification procedures are provided in Method 203A as well, and,
therefore, have not been repeated in this method.
1. Applicability and Principle
1.1 Applicability. This method is applicable for the determination
of the opacity of emissions from sources of visible emissions for
instantaneous limitations. An instantaneous limitation regulation is an
opacity limit which is never to be exceeded.
1.2 Principle. The opacity of emissions from sources of visible
emissions is determined visually by a qualified observer.
2. Procedures
The observer qualified in accordance with section 3 of this method
shall use the following procedures for visually determining the opacity
of emissions.
2.1 Procedures for Emissions From Stationary Sources. Same as 2.1,
Method 203A.
2.1.1 Position. Same as 2.1.1, Method 203A.
2.1.2 Field Records. Same as 2.1.2, Method 203A.
2.1.3 Observations. Make opacity observations at the point of
greatest opacity in that portion of the plume where condensed water
vapor is not present.
Do not look continuously at the plume. Instead, observe the plume
momentarily at the interval specified in the subject regulation. Unless
otherwise specified, a 15-second observation interval is assumed.
2.1.3.1 Attached Steam Plumes. Same as 2.1.3.1, Method 203A.
2.1.3.2 Detached Steam Plumes. Same as 2.1.3.2, Method 203A.
2.2 Procedures for Fugitive Process Dust Emissions.
2.2.1 Position. Same as section 2.2.1, Method 203A.
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2.2.2 Field Records. Same as section 2.2.2, Method 203A.
2.2.3 Observations.
2.2.3.1 Observations for a 15-second Observation Interval
Regulations. Same as section 2.2.3, Method 203A.
2.2.3.2 Observations for a 5-second Observation Interval
Regulations. Same as section 2.2.3, Method 203A, except, observe the
plume momentarily at 5-second intervals.
2.3 Recording Observations. Record opacity observations to the
nearest 5 percent at the prescribed interval on an observational record
sheet. Each momentary observation recorded represents the average of
emissions for the prescribed period. If a 5-second observation period is
not specified in the applicable regulation, a 15-second interval is
assumed. The overall time for which recordings are made shall be of a
length appropriate to the regulation for which opacity is being
measured.
2.3.1 Recording Observations for 15-second Observation Interval
Regulations. Record opacity observations to the nearest 5 percent at 15-
second intervals on an observational record sheet. Each momentary
observation recorded represents the average of emissions for a 15-second
period.
2.3.2 Recording Observations for 5-second Observation Interval
Regulations. Record opacity observations to the nearest 5 percent at 5-
second intervals on an observational record sheet. Each momentary
observation recorded represents the average of emissions for 5-second
period.
2.4 Data Reduction for Instantaneous Limitation Regulations. For an
instantaneous limitation regulation, a 1-minute averaging time will be
used. Divide the observations recorded on the record sheet into sets of
consecutive observations. A set is composed of the consecutive
observations made in 1 minute. Sets need not be consecutive in time, and
in no case shall two sets overlap. Reduce opacity observations by
dividing the sum of all observations recorded in a set by the number of
observations recorded in each set.
2.4.1 Data Reduction for 15-second Observation Intervals. Reduce
opacity observations by averaging four consecutive observations recorded
at 15-second intervals. Divide the observations recorded on the record
sheet into sets of four consecutive observations. For each set of four
observations, calculate the average by summing the opacity of the four
observations and dividing this sum by four.
2.4.2 Data Reduction for 5-second Observation Intervals. Reduce
opacity observations by averaging 12 consecutive observations recorded
at 5-second intervals. Divide the observations recorded on the record
sheet into sets of 12 consecutive observations. For each set of 12
observations, calculate the average by summing the opacity of the 12
observations and dividing this sum by 12.
3. Qualification and Test
Same as section 3, Method 203A.
TABLE A--Smoke Meter Design and Performance Specifications
------------------------------------------------------------------------
Parameter Specification
------------------------------------------------------------------------
a. Light Source........................ Incandescent lamp operated at
nominal rated voltage.
b. Spectral response of photocell...... Photopic (daylight spectral
response of the human eye--
Reference 4.1 of section 4.)
c. Angle of view....................... 15 degrees maximum total angle
d. Angle of projection................. 15 degrees maximum total angle.
e. Calibration error................... 3 percent opacity, maximum.
f. Zero and span drift................. 1 percent opacity, 30 minutes.
g. Response time....................... [le]5 seconds.
------------------------------------------------------------------------
B. Silt Content
Conduct the following test method to determine the silt loading and
silt content of unpaved road and unpaved parking lot surfaces.
(i) Collect a sample of loose surface material from an area 30 cm by
30 cm (1 foot by 1 foot) in size to a depth of approximately 1 cm or
until a hard subsurface is reached, whichever occurs first. Use a brush
and dustpan or other similar device. Collect the sample from a
routinely-traveled portion of the surface which receives a preponderance
of vehicle traffic, i.e. as commonly evidenced by tire tracks. Conduct
sweeping slowly so that fine surface material is not released into the
air. Only collect samples from surfaces that are not wet or damp due to
precipitation or dew.
(ii) Obtain a shallow, lightweight container and a scale with
readings in half ounce increments or less. Place the scale on a level
surface and zero it with the weight of the empty container. Transfer the
entire sample collected to the container, minimizing escape of particles
into the air. Weigh the sample and record its weight.
(iii) Obtain and stack a set of sieves with the following openings:
4 mm, 2 mm, 1 mm, 0.5 mm, and 0.25 mm. Place the sieves in order
according to size openings beginning with the largest size opening at
the top.
[[Page 142]]
Place a collector pan underneath the bottom (0.25 mm) sieve. Pour the
entire sample into the top sieve, minimizing escape of particles into
the air by positioning the sieve/collector pan unit in an enclosed or
wind barricaded area. Cover the sieve/collector pan unit with a lid.
Shake the covered sieve/collector pan unit vigorously for a period of at
least one (1) minute in both the horizontal and vertical planes. Remove
the lid from the sieve/collector pan unit and disassemble each sieve
separately beginning with the largest sieve. As each sieve is removed,
examine it for a complete separation of material in order to ensure that
all material has been sifted to the finest sieve through which it can
pass. If not, reassemble and cover the sieve/collector pan unit and
shake it for period of at least one (1) minute. After disassembling the
sieve/collector pan unit, transfer the material which is captured in the
collector pan into the lightweight container originally used to collect
and weigh the sample. Minimize escape of particles into the air when
transferring the material into the container. Weigh the container with
the material from the collector pan and record its weight. Multiply the
resulting weight by 0.38 if the source is an unpaved road or by 0.55 if
the source is an unpaved parking lot to estimate silt loading. Divide by
the total sample weight and multiply by 100 to arrive at the percent
silt content.
(iv) As an alternative to conducting the procedure described above
in section I.B.(ii) and section I.B.(iii) of this appendix, the sample
(collected according to section I.B.(i) of this appendix) may be taken
to an independent testing laboratory or engineering facility for silt
loading (e.g. net weight < 200 mesh) and silt content analysis according
to the following test method from ``Procedures For Laboratory Analysis
Of Surface/Bulk Dust Loading Samples'', (Fifth Edition, Volume I,
Appendix C.2.3 ``Silt Analysis'', 1995), AP-42, Office of Air Quality
Planning & Standards, U.S. Environmental Protection Agency, Research
Triangle Park, North Carolina.
1. Objective--Several open dust emission factors have been found to
be correlated with the silt content(< 200 mesh) of the material being
disturbed. The basic procedure for silt content determination is
mechanical, dry sieving. For sources other than paved roads, the same
sample which was oven-dried to determine moisture content is then
mechanically sieved.
2.1 Procedure--Select the appropriate 20-cm (8-in.) diameter, 5-cm
(2-in.) deep sieve sizes.
Recommended U. S. Standard Series sizes are 3/8 in., No. 4, No. 40,
No. 100, No. 140, No. 200, and a pan. Comparable Tyler Series sizes can
also be used. The No. 20 and the No. 200 are mandatory. The others can
be varied if the recommended sieves are not available, or if buildup on
1 particulate sieve during sieving indicates that an intermediate sieve
should be inserted.
2.2 Obtain a mechanical sieving device, such as a vibratory shaker
or a Roto-Tap [delta] 1 without the tapping
function.
---------------------------------------------------------------------------
\1\ CFR part 60, App. A, Meth. 5, 2.1.2, footnote 2.
---------------------------------------------------------------------------
2.3 Clean the sieves with compressed air and/or a soft brush. Any
material lodged in the sieve openings or adhering to the sides of the
sieve should be removed, without handling the screen roughly, if
possible.
2.4 Obtain a scale (capacity of at least 1600 grams [g] or 3.5 lb)
and record make, capacity, smallest division, date of last calibration,
and accuracy. (See Figure A)
2.5 Weigh the sieves and pan to determine tare weights. Check the
zero before every weighing. Record the weights.
2.6 After nesting the sieves in decreasing order of size, and with
pan at the bottom, dump dried laboratory sample (preferably immediately
after moisture analysis) into the top sieve. The sample should weigh
between [cent] 400 and 1600 g ([cent] 0.9 and 3.5 lb). This amount will
vary for finely textured materials, and 100 to 300 g may be sufficient
when 90% of the sample passes a No. 8 (2.36 mm) sieve. Brush any fine
material adhering to the sides of the container into the top sieve and
cover the top sieve with a special lid normally purchased with the pan.
2.7 Place nested sieves into the mechanical sieving device and sieve
for 10 minutes (min). Remove pan containing minus No. 200 and weigh.
Repeat the sieving at 10-min intervals until the difference between 2
successive pan sample weighings (with the pan tare weight subtracted) is
less than 3.0%. Do not sieve longer than 40 min.
2.8 Weigh each sieve and its contents and record the weight. Check
the zero before every weighing.
2.9 Collect the laboratory sample. Place the sample in a separate
container if further analysis is expected.
2.10 Calculate the percent of mass less than the 200 mesh screen (75
micrometers [[mgr]m]). This is the silt content.
Figure A. Example silt analysis form.
Silt Analysis
Dated: _____
By: ____________
Sample No: ____ Sample Weight (after drying)
Material: ____
Pan + Sample: ______
Pan: ______
Split Sample Balance: ______
Dry Sample: _______
Make ______ Capacity: ______
Smallest Division ____
Final Weight ______
[[Page 143]]
% Silt = [Net Weight <200 Mesh] / [Total Net Weight x 100] =__%
Sieving
------------------------------------------------------------------------
Time: Start: Weight (Pan Only)
------------------------------------------------------------------------
Initial (Tare):
10 min:
20 min:
30 min:
40 min:
------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------
Final weight (screen
Screen Tare weight (screen) + sample) Net weight (sample) %
----------------------------------------------------------------------------------------------------------------
\3/8\ in..........................
4 mesh............................
10 mesh...........................
20 mesh...........................
40 mesh...........................
100 mesh..........................
140 mesh..........................
200 mesh..........................
Pan...............................
----------------------------------------------------------------------------------------------------------------
(v) The silt loading and percent silt content for any given unpaved
road surface or unpaved parking lot surface shall be based on the
average of at least three (3) samples that are representative of
routinely-traveled portions of the road or parking lot surface. In order
to simplify the sieve test procedures in section I.B.(ii) and section
I.B.(iii) of this appendix, the three samples may be combined as long as
all material is sifted to the finest sieve through which it can pass,
each sample weighs within 1 ounce of the other two samples, and the
combined weight of the samples and unit area from which they were
collected is calculated and recorded accurately.
II. Vacant Lots
The following test methods shall be used for determining whether a
vacant lot, or portion thereof, has a stabilized surface.
Should a disturbed vacant lot contain more than one type of
disturbance, soil, vegetation or other characteristics which are visibly
distinguishable, test each representative surface for stability
separately in random areas according to the test methods in section II.
of this appendix and include or eliminate it from the total size
assessment of disturbed surface area(s) depending upon test method
results. A vacant lot surface shall be considered stabilized if any of
the test methods in section II. of this appendix indicate that the
surface is stabilized such that the conditions defined in paragraph
(b)(16)(ii) of this section are met:
1. Visible Crust Determination
(i) Where a visible crust exists, drop a steel ball with a diameter
of 15.9 millimeters (0.625 inches) and a mass ranging from 16 to 17
grams from a distance of 30 centimeters (one foot) directly above (at a
90 degree angle perpendicular to) the soil surface. If blowsand is
present, clear the blowsand from the surfaces on which the visible crust
test method is conducted. Blowsand is defined as thin deposits of loose
uncombined grains covering less than 50 percent of a vacant lot which
have not originated from the representative vacant lot surface being
tested. If material covers a visible crust which is not blowsand, apply
the test method in section II.2 of this appendix to the loose material
to determine whether the surface is stabilized.
(ii) A sufficient crust is defined under the following conditions:
once a ball has been dropped according to section II.1.(i) of this
appendix, the ball does not sink into the surface so that it is
partially or fully surrounded by loose grains and, upon removing the
ball, the surface upon which it fell has not been pulverized so that
loose grains are visible.
(iii) Conduct three tests, dropping the ball once per test, within a
survey area the size of one foot by one foot. The survey area shall be
considered sufficiently crusted if at least two out of three tests meet
the definition in section II.1.(ii) of this appendix. Select at least
two other survey areas that represent the disturbed surface area and
repeat this procedure. Whether a sufficient crust covers the disturbed
surface area shall be based on a determination that all of the survey
areas tested are sufficiently crusted.
(iv) At any given site, the existence of a sufficient crust covering
one portion of a disturbed surface may not represent the existence or
protectiveness of a crust on another disturbed surface(s). Repeat the
visible crust test as often as necessary on each representative
disturbed surface area for an accurate assessment of all disturbed
surfaces at a given site.
[[Page 144]]
2. Determination of Threshold Friction Velocity (TFV)
For disturbed surface areas that are not crusted or vegetated,
determine threshold friction velocity (TFV) according to the following
sieving field procedure (based on a 1952 laboratory procedure published
by W. S. Chepil).
(i) Obtain and stack a set of sieves with the following openings: 4
millimeters (mm), 2 mm, 1 mm, 0.5 mm, and 0.25 mm. Place the sieves in
order according to size openings beginning with the largest size opening
at the top. Place a collector pan underneath the bottom (0.25 mm) sieve.
Collect a sample of loose surface material from an area at least 30 cm
by 30 cm in size to a depth of approximately 1 cm using a brush and
dustpan or other similar device. Only collect soil samples from dry
surfaces (i.e. when the surface is not damp to the touch). Remove any
rocks larger than 1 cm in diameter from the sample. Pour the sample into
the top sieve (4 mm opening) and cover the sieve/collector pan unit with
a lid. Minimize escape of particles into the air when transferring
surface soil into the sieve/collector pan unit. Move the covered sieve/
collector pan unit by hand using a broad, circular arm motion in the
horizontal plane. Complete twenty circular arm movements, ten clockwise
and ten counterclockwise, at a speed just necessary to achieve some
relative horizontal motion between the sieves and the particles. Remove
the lid from the sieve/collector pan unit and disassemble each sieve
separately beginning with the largest sieve. As each sieve is removed,
examine it for loose particles. If loose particles have not been sifted
to the finest sieve through which they can pass, reassemble and cover
the sieve/collector pan unit and gently rotate it an additional ten
times. After disassembling the sieve/collector pan unit, slightly tilt
and gently tap each sieve and the collector pan so that material aligns
along one side. In doing so, minimize escape of particles into the air.
Line up the sieves and collector pan in a row and visibly inspect the
relative quantities of catch in order to determine which sieve (or
whether the collector pan) contains the greatest volume of material. If
a visual determination of relative volumes of catch among sieves is
difficult, use a graduated cylinder to measure the volume. Estimate TFV
for the sieve catch with the greatest volume using Table 1, which
provides a correlation between sieve opening size and TFV.
Table 1 (Metric Units)--Determination of Threshold Friction Velocity
(TFV)
------------------------------------------------------------------------
Opening TFV (cm/
Tyler Sieve No. (mm) s)
------------------------------------------------------------------------
5.................................................. 4 >100
10................................................. 2 100
18................................................. 1 76
35................................................. 0.5 58
60................................................. 0.25 43
Collector Pan...................................... ......... 30
------------------------------------------------------------------------
Collect at least three (3) soil samples which are representative of
the disturbed surface area, repeat the above TFV test method for each
sample and average the resulting TFVs together to determine the TFV
uncorrected for non-erodible elements.
(ii) Non-erodible elements are distinct elements on the disturbed
surface area that are larger than one (1) cm in diameter, remain firmly
in place during a wind episode and inhibit soil loss by consuming part
of the shear stress of the wind. Non-erodible elements include stones
and bulk surface material but do not include flat or standing
vegetation. For surfaces with non-erodible elements, determine
corrections to the TFV by identifying the fraction of the survey area,
as viewed from directly overhead, that is occupied by non-erodible
elements using the following procedure. Select a survey area of one (1)
meter by 1 meter. Where many non-erodible elements lie on the disturbed
surface area, separate them into groups according to size. For each
group, calculate the overhead area for the non-erodible elements
according to the following equations:
(Average length) x (Average width) = Average Dimensions Eq. 1
(Average Dimensions) x (Number of Elements) = Overhead Area Eq. 2
Overhead Area of Group 1 + Overhead Area of Group 2 (etc.) = Total
Overhead Area Eq. 3
Total Overhead Area/2 = Total Frontal Area Eq. 4
(Total Frontal Area/Survey Area) x 100 = Percent Cover of Non-erodible
Elements Eq. 5
(Ensure consistent units of measurement, e.g. square meters or square
inches when calculating percent cover.)
Repeat this procedure on an additional two (2) distinct survey areas
representing a disturbed surface and average the results. Use Table 2 to
identify the correction factor for the percent cover of non-erodible
elements. Multiply the TFV by the corresponding correction factor to
calculate the TFV corrected for non-erodible elements.
[[Page 145]]
Table 2--Correction Factors for Threshold Friction Velocity
------------------------------------------------------------------------
Percent cover of non-erodible elements Correction factor
------------------------------------------------------------------------
[ge]10%.................................... 5
[ge]5% and < 10%........................... 3
< 5% and [ge] 1%........................... 2
< 1%....................................... None.
------------------------------------------------------------------------
3. Determination of Flat Vegetation Cover
Flat vegetation includes attached (rooted) vegetation or unattached
vegetative debris lying on the surface with a predominant horizontal
orientation that is not subject to movement by wind. Flat vegetation
which is dead but firmly attached shall be considered equally protective
as live vegetation. Stones or other aggregate larger than one centimeter
in diameter shall be considered protective cover in the course of
conducting the line transect method. Where flat vegetation exists,
conduct the following line transect method.
(i) Stretch a one-hundred (100) foot measuring tape across a
disturbed surface area. Firmly anchor both ends of the measuring tape
into the surface using a tool such as a screwdriver with the tape
stretched taut and close to the soil surface. If vegetation exists in
regular rows, place the tape diagonally (at approximately a 45 degree
angle) away from a parallel or perpendicular position to the vegetated
rows. Pinpoint an area the size of a \3/32\ inch diameter brazing rod or
wooden dowel centered above each one-foot interval mark along one edge
of the tape. Count the number of times that flat vegetation lies
directly underneath the pinpointed area at one-foot intervals.
Consistently observe the underlying surface from a 90 degree angle
directly above each pinpoint on one side of the tape. Do not count the
underlying surface as vegetated if any portion of the pinpoint extends
beyond the edge of the vegetation underneath in any direction. If clumps
of vegetation or vegetative debris lie underneath the pinpointed area,
count the surface as vegetated unless bare soil is visible directly
below the pinpointed area. When 100 observations have been made, add
together the number of times a surface was counted as vegetated. This
total represents the percent of flat vegetation cover (e.g. if 35
positive counts were made, then vegetation cover is 35 percent). If the
disturbed surface area is too small for 100 observations, make as many
observations as possible. Then multiply the count of vegetated surface
areas by the appropriate conversion factor to obtain percent cover. For
example, if vegetation was counted 20 times within a total of 50
observations, divide 20 by 50 and multiply by 100 to obtain a flat
vegetation cover of 40 percent.
(ii) Conduct the above line transect test method an additional two
(2) times on areas representative of the disturbed surface and average
results.
4. Determination of Standing Vegetation Cover
Standing vegetation includes vegetation that is attached (rooted)
with a predominant vertical orientation. Standing vegetation which is
dead but firmly rooted shall be considered equally protective as live
vegetation. Conduct the following standing vegetation test method to
determine if 30 percent cover or more exists. If the resulting percent
cover is less than 30 percent but equal to or greater than 10 percent,
then conduct the Threshold Friction Velocity test in section II.2 of
this appendix in order to determine whether the disturbed surface area
is stabilized according to paragraph (b)(16)(ii)(E) of this section.
(i) For standing vegetation that consists of large, separate
vegetative structures (for example, shrubs and sagebrush), select a
survey area representing the disturbed surface that is the shape of a
square with sides equal to at least ten (10) times the average height of
the vegetative structures. For smaller standing vegetation, select a
survey area of three (3) feet by 3 feet.
(ii) Count the number of standing vegetative structures within the
survey area. Count vegetation which grows in clumps as a single unit.
Where different types of vegetation exists and/or vegetation of
different height and width exists, separate the vegetative structures
with similar dimensions into groups. Count the number of vegetative
structures in each group within the survey area. Select an individual
structure within each group that represents the average height and width
of the vegetation in the group. If the structure is dense (i.e. when
looking at it vertically from base to top there is little or zero open
air space within its perimeter), calculate and record its frontal
silhouette area according to Equation 6 of this appendix. Also use
Equation 6 if the survey area is larger than nine square feet,
estimating the average height and width of the vegetation. Otherwise,
use the procedure in section II.4.(iii) of this appendix to calculate
the Frontal Silhouette Area. Then calculate the percent cover of
standing vegetation according to Equations 7, 8 and 9 of this appendix.
(Ensure consistent units of measurement, e.g. square feet or square
inches when calculating percent cover.)
(iii) Vegetative Density Factor. Cut a single, representative piece
of vegetation (or consolidated vegetative structure) to within 1 cm of
surface soil. Using a white paper grid or transparent grid over white
paper, lay the vegetation flat on top of the grid (but do not apply
pressure to flatten the structure). Grid boxes of one inch or one half
inch squares are sufficient for most vegetation when conducting this
procedure. Using a marker or pencil, outline the shape of the vegetation
[[Page 146]]
along its outer perimeter according to Figure B, C or D of this
appendix, as appropriate. (Note: Figure C differs from Figure D
primarily in that the width of vegetation in Figure C is narrow at its
base and gradually broadens to its tallest height. In Figure D, the
width of the vegetation generally becomes narrower from its midpoint to
its tallest height.) Remove the vegetation and count and record the
total number of gridline intersections within the outlined area, but do
not count gridline intersections that connect with the outlined shape.
There must be at least 10 gridline intersections within the outlined
area and preferably more than 20, otherwise, use smaller grid boxes.
Draw small circles (no greater than a \3/32\ inch diameter) at each
gridline intersection counted within the outlined area. Replace the
vegetation on the grid within its outlined shape. From a distance of
approximately two feet directly above the grid, observe each circled
gridline intersection. Count and record the number of circled gridline
intersections that are not covered by any piece of the vegetation. To
calculate percent vegetative density, use Equations 10 and 11 of this
appendix. If percent vegetative density is equal to or greater than 30,
use the equation (Eq. 14, 15 or 16) that matches the outline used to
trace the vegetation (Figure B, C or D) to calculate its Frontal
Silhouette Area. If percent vegetative density is less than 30, use
Equations 12 and 13 of this appendix to calculate the Frontal Silhouette
Area.
(iv) Within a disturbed surface area that contains multiple types of
vegetation with each vegetation type uniformly distributed, results of
the percent cover associated with the individual vegetation types may be
added together.
(v) Repeat this procedure on an additional two (2) distinct survey
areas representing the disturbed surface and average the results.
Height x Width = Frontal Silhouette Area Eq. 6
(Frontal Silhouette Area of Individual Vegetative Structure) x Number of
Vegetation Structures Per Group = Group Frontal Silhouette Area of Group
Eq. 7
Frontal Silhouette Area of Group 1 + Frontal Silhouette Area of Group 2
(etc.) = Total Frontal Silhouette Area Eq. 8
(Total Frontal Silhouette Area/Survey Area) x 100 = Percent Cover of
Standing Vegetation Eq. 9
[(Number of circled gridlines within the outlined area counted that are
not covered by vegetation / Total number of gridline intersections
within the outlined area) x 100] = Percent Open Space Eq. 10
100 = Percent Open Space = Percent Vegetative Density Eq. 11
Percent Vegetative Density/100 = Vegetative Density Eq. 12
[GRAPHIC] [TIFF OMITTED] TR21DE99.000
[[Page 147]]
[GRAPHIC] [TIFF OMITTED] TR21DE99.001
Alternative Test Methods
Alternative test methods may be used upon obtaining the written
approval of the EPA.
[64 FR 71308, Dec. 21, 1999]