96009.017
REPORT ON THE
COLLECTION AND COMPILATION OF DATA ON
POINT SOURCES OF AIR POLLUTANTS EMISSIONS
FOR THE STATE OF MARYLAND AND DISTRICT OF COLUMBIA
Contract No. 68-02-0048
Task Order 10
27 October 1972
Prepared For
Environmental Protection Agency
Research Triangle Park, N.C.
Prepared By
TRW Inc.
Transportation & Environmental Operations
Environmental Services
7600 Colshire Drive
McLean, Virginia
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INTRODUCTI ON
This report summarizes the scope of the effort on the Maryland and
District of Columbia point sources inventory update. This work was
performed under Task Order 10, Contract No. 68-02-0048.
POWER PLANTS
Most of the power plant load sheets were obtained from Federal Power
Commission reports obtained from the EPA Project Officer and entitled
“Steam-Electric Plant Air and Water Quality Control Data for Year Ended
December 31, 1969” (FPC Form 67) and the same report-dated December 31,
1970. These reports were sufficiently detailed to provide all required
data with the exception of UTM coordinates. The coordinates were converted
from the Maryland grid coordinates in the printout. UTM coordinates for
the D.C. power plants were obtained from the D.C. air pollution control
officials’ files. Boilers were apportioned to stacks for all the power
plants appearing in the Federal Power Commission reports.
FEDERAL FACILITIES
Point source data on Federal facilities in the District of Columbia
and Maryland were obtained from EPA’s computer printout “Federal Facilities
Emissions.” The data were coded on the NEDS forms in accordance with
the instructions and examples in the letter from John C. Bosch, dated
August 4, 1972, subject: Coding of Federal Point Source Information on
NEDS Data Forms.
f1ARYLAND FACILITIES
The questionnaires in the Maryland data file were not always complete.
Additionally, some inconsistencies were found in the data,.
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Data for private sources and some power plants were extracted from
State of Maryland air pollution source inventory printouts and the State
of Maryland file of this inventory. Data were first taken from the print-
outs and entered onto computer load sheets. Later, additional data were
extracted from the Maryland files and entered onto these same load sheets
At this time, the data first extracted from the printouts were verified
against the Maryland files.
The Maryland files contained, in addition to letters, text, and
diagrams, a multitude of questionnaires (some old format and others new
format) for the same piece of equipment. The forms, of various dates and
at various stages of completion, were spread throughout the file made up
for the particular establishment. The old forms have certain data
(particularly stack data) required on the NEDS load sheets and not found
on the new forms. Therefore, data were first taken from the most up—to-
date new type form and then additional data were taken from the most up-.
to—date old type form. Then the file was searched for whatever data were
still missing.
In the case of identical units of equipment at any facility covered
by the Maryland file, all units were covered by one questionnaire. The
amounts processed, produced, combusted, etc., appearing on the questionnaire
were intended to be totals for all units covered by the questionnaire;
while fuel rate capcities, MBTU per hour capacities, production per hour,
processed material per hour, and other rates were to be per unit quantities.
However, rate per hour values sometimes appeared to be a total for all
units; while at other times, total production, process, fuel combustion,
etc., amøunts were suspected to. really be per unit amounts. These
inconsistencies may have provided some error in the data transcribed
onto the NEDS load sheets.
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Specific problem areas were as follows.
City Code Numbers
Where the city code number was not available, this field was left
blank.
Mailing Address
nailing addresses were completed from the Maryland files. Often the
field was not long enough to completely fit even an abbreviated name and
address. in such cases, the balance of the address was put below the field.
The complete name and address was put on only the first load sheet of
each facility, to save time.
Stack Data
In nearly all cases, it was not too apparent what units fed which
stacks. It was therefore decided, with EPA’s concurrence, that a separate
load sheet be filled out for each piece of equipment, instead of for each
stack. In addition, it was not always possible to apportion flow rates nor
diameters to specific units. Stack data entered onto load sheets .ere most
often actual stack data, unapportioned.
Combustion source questionnaires in the Maryland file just provided for
stack height. The balance of the stack data was missing. Process source
questionnaires in the Maryland files provided a11 required 3tack data.
However, diameters had to be converted from inches to feet and flow rates
were obtained by multiplying gas velocities by calculated cross—sectional
areas. quiva1ent stack diameters were calculated for stacks with rectangu-
lar cross—sections. Where stack data were not available, plume height was
also left blank.
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SIC and IPP Process Codes
Though a SIC code that described the manufacturing process could
nearly always be found in the printout, selecting a satisfactory IPP
process code from those available was not necessarily possible. The
equipment or process description on the questionnaire might be for only
a portion of that process described by the IPP process code. In many
cases, only a person with detailed knowledge of the particular process
could pick the correct code.
Boiler Design Capacities
These capacities were obtained from the Maryland files. It is suspected
that sometimes the values shown on the multiple units’ questionnaires were
totals rather than per unit values.
Control Equi pment Types
Control equipment types were identified in the printout, but control
efficiencies were not given. Control equipment efficiencies were obtained
from the Maryland questionnaires. The efficiencies were necessary for
selecting the control equipment code numbers. When efficiencies were
lacking, this field was left blank and the .generic name of the device written
above the field. Sometimes diagrams in the Maryland files provided insight
into how the control equipment served the process equipment and boilers.
These diagrams would show if control equipments were in parallel or series
with one another and integrated efficiencies could be calculated.
Normal Operating Times
These times were obtained from the Maryland files. Only the process
questionnaires provided for these data; the combustion questionnaires did
not. In the case of boilers, it was necessary to make educated
assumptions based on the operating times of boiler-associated processes or
use of the boiler.
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Emission Estimates
Emission estimates were taken from the printout and verified against
the Maryland files. Carbon monoxide emissions were not given for boilers.
These emissions were calculated from fuel usage. On several occasions,
emissions were calculated using EPA approved emission factors and found
to differ from the State of Maryland estimated emissions. In such cases,
the Maryland estimated emissions were used. It is therefore probable that i-f
calculations are performed they will differ from Maryland’s estimates.
Percent Space Heat
Percent space heat, except for a rare once or twice, was not found
either in the computer printout or the source questionnaires.
SCC Numbers
It was often not possible to find SCC numbers that would completely
satisfy the reported process. Interpretation of satisfying SCC numbers
has probably varied between persons filling load sheets. In most cases,
many processes and equipments contributed to a .firiished product. Therefore,
it was desirable to first search for a process related 5CC number before
settling for a product related number (e.g, if they fabricate metal parts,
but the process is painting these parts, then 40200101 would be used
instead of 30900199).’ In cases where available SCC codes did not adequately
describe the process, 9’s were entered in the appropriate fields.
Operatin g Rate
These &nnual rates were taken from the Maryland files. Units corresponded
to thos?listed for. the related- SCC number. When these rates were missing
from the questionnaire, the space was left blank.
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Maximum Design Rate
These rates were either obtained from the questionnaires in the Maryland
files or calculated by dividing the number of hours of operation into the
operating rate. The calculation probably resulted in a value considerably
lower than the actual maximum design rate.
Heat Content
This field was mostly left blank since the heat content was rarely given
in the questionnaires and did not appear in the printouts.
Comments
This field was used to identify the equipment and/or process. The
printout showed equipment code numbers which were used to provide the
initial entries into this field. These entries were later modified using
the Maryland files. It as found that the equipment code numbers often
did not accurately reflect the actual process as identified in the Maryland
questionnaires.
D.C. FACILITIES
Data in the files maintained by D.C. air pollution control officials
were compiled by facilities rather than by individual equipment . However,
this had little effect on filling out the load sheets since the only D.C.
process sources were petroleum storage tanks. Data missing from the D.C.
load sheets were not available in the D.C. files.
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