U. S. DEPARTMENT OF HEALTH, EDUCATION. AND WELFARE
Public Health Service
Environmental Health Service
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Office of Air Programs Publication No. APTD-0880
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DENVER AIR POLLUTANT EMISSION INVENTORY
Prepared by:
Clyde Morita
Guntis Ozolins
George Duggan
DEPARTMENT OF HEALTH. EDUCATION, AND WELFARE
U, S, Public Health Service
National Air Pollution Control Administration
Air Quality and Emission Data Program
Durham, North Carolina
August, 1968
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ACKNOh'LEDGHENT
The Public. Health Service acknoHledges \vith apprecfation the many
-... contributio~s of cooperating agencies in the publication of this report.
In particular, we are. grateful for the use of qata and personnel assist-
ance furnished by the following:
Colorado State Department of Public
Health, .Tri-County District Health Department, Boulder City - County
Health Department, Denver City and Co~nty Air Pollution Section, and the
Jefferson County Health Department.
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CON TEN T S
INTRODUCTION
STUDY AREA
SUHNARY OF RESULTS'
'.
EMISSIONS BY CATEGORY.
Fuel Combustion in Stationary Sources
Transportation.
.: .
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~~~~.
Solid - Waste Disposal.
Industrial Process Losses
EMISSIONS BY GRIDS.
REFERENCES.
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4
7
10
17
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26
33
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AIR POWJTANT EHISSION, INVENTORY
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, INTRODUCTION
, 1
This report presents the results of a rapid emission inventory of
air pollutant sources in the Denver metropolitan area.
The objectives of
---'-"---~his--s tuCfy "were" to dctermi'ncH the'-Eotal quanti ties ot vart"ous--'aIr politi ta'ntS' ..------
..emitted and to estim~te the. geographical and seasonal variation in air pol-
--_,____l,ut_a!l:t.. ,c!!li::;sions., - _T~ ,accomplish this ..task, t}:~. St,:udy- ~rea..,w8:s, _~iv~ded.. ----'. _-h"h..--.
into a grid coordinate system and the ~ilission quantities were reported
in terms of tons of pollutant per grid on an average annual day, average
summer day, and average winter day.
.'"
The pollutants considered in this survey are sulfur oxides, parti-
culates, .and carbon monoxide.
The emissions of other pollutants were
, '. not estimated due to a limrt'at'ion of time, personnel, and available data.
Data presented herein are representative of 1967 and were mainly gathered
by the acknowledged State and local agencies.
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STUDY AREA
The Study Area, as presented in Figure 1, consists' of the City and
'"
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County of Denver, and the Counties of Adams, Arapahoe, Boulder, Jefferson,
Larimer, and Weld.
This area occupies lO~305 square miles and contains
an estimated 1967 population of 1,235,000.
Table 1 shows the land areas
and the 1960 and 1967 populations for each of the major political
jurisdictions.
Approximately 63% of the State population resides in this area which
comprise$ about 10% of the land area of the State.
Larimer and '\~~d
Counties aie outside the defined boundaries of the Denver Standard
1
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(:\GUR~ L - D£NVtR STUDY ARtA
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LARiM[R
W~LD
. . - - -.. - _.- .
,.,
, BOULDbR
.
ADAMS
J~~f[RSON
ARAPAWO~
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Table 1.
DENVER STUDY AREA CHARACTERISTICS2, 1967
Political Jurisdiction Land Area Population Population
(sq. roi.>' 1960 1967 Density
(1967)
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Denver SNSA 3,687 929,000 1,083,000 294
Adams County 1,241 120,000 157,000 126
Arapahoe 'County 801 113,000 131,000 164
Boulder County 758 74,000 105,000 139
Denver City & County 98 494,000 485,000 4,950
J~fferson County 789 128,000 205,000 260
Larimer County ,,' 2,614 53,000 72,000* 28
'~e1d .County . 4,004 . 72,000 80,000* 20
Total Study Area 10,305 1tOS4~000: 1,235,000 120
'" = Estimated /
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Metropolitan Statistical Area (SMSA); however, their proximity and degree
. of industrialization necessit~te~ their inclusion within the Study Area.
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The Colorado Springs ~~~A is located approximately 68 miles South of
Denver.
Due to the direction of prevailing winds and tbe sheltering effect
of the foothills bet'.,reen the metropolitan areas, Colorado Springs "las
not included in this study.
~ogra1.?l2L
Most of the Study Area is situated east of the foothills of the'Rocky
Hountains.
This area is fairly level with an elevation of 5,000 to 5,500
feet above mean sea level.
The foothills are located 18 miles west of
. Denver and rise from the plateau area to greater: .,than 13,000 feet, in the
main ranges, along the western extremities of the Study Area.
Denver,
itself, is approximately 40 miles east of the main range of the Rocky
M . 3
ounta1ns .
Grid Coordinate System
For the purposes of this survey, the Study Area was divided into 81
grids based on latitude and longitude.
Five grid sizes of 2 minute, 4 min-
ute, 8 minute, 16 minute, and 32 minute grids were utilized depending upon
,;
the extent of urbanization of the area.
Figure 2 indicates the grid
system used for reporting the emissions.
In those cases where sections
of outlying counties are omitted, the air pollutant emissions arc consid-
ered negligible.
Sm~~RY OF PillSULTS
The estimated annual emissions of the three surveyed pollutants, in
the Study Area, are 31,400 tons ?f sulfur oxides, 33,400 tons of particulates,
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rtGURl2 - REPORTING lON[S ~OR
D[NVER STUDY AR~A
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and 616",000 tons of carbon monoxide.
The air pollutant emlssions by
~olitica1 jurisdiction are indicated in Table 2.
Denver has the highest
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emission rate of particulates and carbon monoxide. and Adams County the
highest emission rate of sulfur oxides.
Table 3 lists the breakdo~~ of pollutant emissions by source cate-
gory in the Study Area.
The following is a brief summary of pollutant
emissions and sources:
(1)
Of the 31,'tOO tons of sax emit ted annually. 67% originate from
fuel combustion sources, 28% from industrial process losses, and
5% from mobile sources.
The contribution from solid waste dis-
---.. - - .
posal is negligible.
The combustion of coal, mainly in steam
electric power plants, produces 62% of'the total sulfur oxides
,in the areq..
(2)
Particulate emissions from fuel combustion contribute 54%,
solid waste disposal 4%, industrial process losses 27%, and
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mobile sources 15% of the 33,400 tons of particulates emitted
in the Study Area.
"The combustion of coal produces 50% 'of the
total particulate endssions.
(3)
Mobile sources contribute 94% of the 616,000 tons of CO emitted
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per year.
Other sources are the combustion of fuels in station-
ary sources which contribute less than 1%, solid waste disposal
1%, and industrial process losses 4%.
DIISSIONS BY CATEGORY
For purposes of compiling the basic data and emission estimates, the
air pollutant sources were classified into the following four categories:
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Table 2.
EMISSIONS BY POLITICAL JURISDICTION
(tons/year)
County SOx Part. CO
-
Adams 15,100 8,980 ,---'" -. ------
I 94,300 ,
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Arapahoe 320 1,180 , 81,700
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Boulder 5,630 4,550 I
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Denver 6 , -9 5 0 9,370 ; 241,600
!
Jefferson i
1,350 4,670 \ 115,700
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SMSA Total 29,400 ,.28,800 ! 567,000
Larimer 910 i
2,000 \ 22,200
Weld- 1,070 2,600 26,400
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Study Area Total 31,400 33,400 1616,000
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Table 3.
EMISSIONS BY SOURCE CATEGORY IN STUDY AREA, 1967
(tons/year)
Source category
Fuel combustion
(Stationary sources)
Total
SOx Part.
19,300 16,700
1,000 300
570* 1,200
20,900 .18,200
CO
Coal
.- Oil
Gas
r--,::..'
I I 4,400 .
I ---. --. -.
, 100
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4,500
Solid waste disposal
I. -_0.-.' --. ._4
Open burning
Incineration
On-site
B~ckyard
Incineration
Total
n 100
n n
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13 550
39 650
. 50 1,300
. 8,800 8,900
970
n
6,600
2,200
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9,800
Industrial process
24,700
Mobile sources
Gasoline combustion
Diesel combustion
Railroads
Aircraft
Total
1,000 2,300 563,900
500 1,300 800
100 300 200
n 1,100 11,500
1,600 5,000 576,00"0
n = negligible
* 550 tons/year due to burning of a surpl us '$tock of mustard gas
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(1)
Fuel combustion in S~ationary Sources
(2)
Transportation
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(3)
(4)
Solid - t~aste Disposal
Industrial process losses
In the following sections, each of the categories is discussed and a
summary of the resulting emissions is presented.
Fuel Combustion in Stationary Sources
Although all of the three major fuels are consumed within the Study
Area, natural gas is by far the most important. In 1967, natural gas
accounted for 110 x 1012 BTUs or approximately 63 percent of the total
energy input.
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As sho~~ in Table 4, approximately 2,330,000 tons of coal,
210,000 barrels of residual fuel oil, 350,000 barrels of distillate fuel
'oil and 131.2 billion cubic feet of natural gas were consumed in the Study
. Area.
~1ereas the coal and natural gas consumption data. are fairly
accurate, the fuel oil data is a rough estimate, based partially on 1962
d t 4,5
a a .
Much of the difficulty with respect to defining fuel oil use
data is due. to the fact that oil, especially residual fuel oil, is used
as standby fuel for interruptible gas consumers.
Because of variability /
in climatic conditions, the annual consumption of fuel oil may therefore
vary
significantly from one year to the next.
The sulfur and ash contents of the fuels used in the Study Area are
summarized in Table 5.
The sulfur contents of both coal and fuel oil are
relatively 1m...,
There are five steam - electric generating plants Hithin the Study
'Area.
Fuel combustion for each of these is summarized in Table 6.
These
. plants used 85% of the total coal consumed in the Study Area.
All of the
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Table 4,
Steam-electric utilities
Ind~stry
Residential
Commercial-institutional
Total
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FUEL CONSUMPTION IN STUDY AREA, 1967
Coal
(1,000 tons)
Fuel Oil
Residual Distillate
.(1,00'0 bbl.) (1,000 bbl.)
25 ,-
160 58
270
25 . 22
210 350
1,973
229
20
110
2,332
Natural Gas
(106 cu. ft.)
16,248
~27,677
53,559
33,745
131,229
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Table 5.
SULFUR AND ASH CONTENT OF FUELSi~, 1967
Fuel
% Sulfur
% Ash
.-
Coal
0.6
0.7
6.0
Residual Fuel Oil
-'
Distillate Fuel Oil
0.3
Natural Gas
,0.0008
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*Information gathered from local officials and
fuel companies,
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4.
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Table
6. FUEL CONSUNPTION IN STEM! ELECTRIC GENERATING PLANTS~' 7 1967
Arapahoe (City of Denver)
Zuni (City of Denver) .
Cherokee (Adams County)
Valmont (Boulder County)
Ft. Collins (Larimer County)
Total
a .'
Equipped'with cyclones and ESP.
. b . .
Equ~pped with cyclones and ESP.
c
Equipped with ESP.
dEquipped with cyclone and ESP.
. e
No control.
Coal
(tons)
233',600a
134,300b
'1,034,OOOc
, 558,OOOd
l3,OOOe
1,972,900
(~
Fuel 011
(barrels)
.24,700
.,-
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2/.,700
Gas
(mill. cu. ft.)
.9,607
6,427
---
214
16,248
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plants except Ft. Collins are equipped with some form of air pollution
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.control device.
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The primary fuel used by industry is natural gas.
Except for a few
large consumers of coal and fuel oil, these fuels. are used primarily for
standby purposes.
Six plants collectively consumed over 170,000 tons of
coal or 747. of the total coal used in all industrial operations.
Fuel use
in the co~nercial and institutional category is not well defined.
Here
again, interruptible gas supplemented by fuel oil-residual and distillate.
is used.
The largest knO\m users of the heavy fuels are public schools
(4,000 tons of coal), Lowry Air Force Base (14,000 tons of coal) and the
Federal Center (24,000 tons of coal),
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Close to 100 percent of the residences in the urbanized portion of
the Study Area are ~erved by natural gas.
The outlying areas as well as
major housing developments throughout the Area are .partially heated by
distillate fuel oil and to lesser extent - by coal.
An estimated 270,000
"barrels of fuel oil and 20,000 tons of coal are used for these purposes.
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Emissions from Fuel Combustion
The air pollutant emissions resulting from fuel.combustion in station-
ary sources are listed ~n Table 7.
The emissions are presented for
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industrial, commercial and institutional, residential., and steam-electric
utility sources.
Although the combustion of coal accounts for 357. of the BTU comSUDp-
tion within the Studv Area, coal contributes 94% of the SO , 927. of the
.. . x
particulates, and 98% of the CO resulting from the combustion of fuels.
The majority of these emissions are isolated in a fe,~:large fuel consumers
such as power plants, large industries and institutions.
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Table 7.
AIR POLLUTANT EHISSIO:JS FRO:'1 COHBUSTION OF
FUELS IN THE STUDY AREA (tons/yr.)
Fuel Use"r Category Pollutant Emissions
SOx Part. CO
Coal Industrial 2,770 5,670 380
Commercial & Institutional 1,140 4,370 2,760
Residential 430 820 1,020
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Stearn-Electric Utilities 15,000 5,810 210
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Fuel Oil . Industrial 500 170 115
Commercial & Institutional 230 70 3
Residential 230 60 10
Pm-1er 55 5 neg.
Natural Gas Industrial 7 250 7
Commercial & Institutional 555)': 320 neg.
Residential '9 460 9 ,/
PO\-1er neg. 120 neg.
*550 tons SOx/yr. due to burning of mustard gas.
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The co~bustion of fuels, m~inly coal, in the five steam-electric
'--
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utilities accounts for 48% of the SOx and 177. of the particulates generated
in the Study Area.
The particulate contribution is low since the majority
of the plants have electrostatic precipitators.
The emissions resulting from the combustion of fuel oil and natural
gas are minor compared to tnat from coal combustion.
A unique problem is
the 550 tons per year of sulfur oxides resulting from the burning o.f surplus
mustard gas at one of the federal facilities in Adams County.
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Data Sources
The natural gas consumption data by consumer category ,~as provided by
the Public Service Company of Colorado.
Fuel ,consumption by each of their
four steaul-electric utility plants in the Study Area was a1so provided;
consumption for the Fort Collins plant, operated by the Fort Collins Light
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& Power Department, was obtained from "Steam Electric Plan~ Factors.,,7.
}
Coal consumption by industrial, residential, an? commercial-institu-
tional sourc'es '~as established on the basis of information gathered from
,-.----" --' --. . ----_._- - -- - .
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. ----. -_.- -_._-
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local coal dealers.
The major consumers of coa1~ad been previously
I contacted individually by l~cal agencies.
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Fuel oil consumption ,data for industrial establishments were obtained
from "Distiliate and Residual Fuel' Oil Consumed in Manufacturing Industries:
1962,,5.
Fuel oil consumed by residential units in the Study Area ,vas
assumed to be only distillate.
Dwelling unit data (1960) and type of
. 1,9
, heating equipment were utilized to calculate fuel oil consumpt1on.
Com-
mercial and institutional sources of f~e1 oil were obtained from the major
users, and estimate.d for those users for which data was not available.
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~nsportation
Three ty~es of transportation sources of air pollution are considered
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in this survey - motor vehicles; aircraft, and railroads.
The emissions
caused by the operation of motor vehicles is furtner subdivided according
to type of fuel - gasoline or diesel.
Motor Vehi.cles
On the basis of gasoline sales data, it is estimated that approximately
~ 10 11
~7S million gallons of gasoline' were sold in the Study Area during
1967.
Gasoline sales and automobile registrations by major political sub-
divisions are presented in Table 8.
The total of 475 million gallons
includes both hig}nvay and non-high~.;ray uses.
Because the non~highway uses
account for only S to 7 percent, they were considered together ~.;rith the
high~vay uses.
Approximately 1.S to 2.0 percent of gasoline is lost through evapora-
tion resulting in annual losses of about 9.S'million gallons.
The
consumption of gasoline by political subdivisions is presented in Table 9.
The apportionment of gasoline consumption ,vas accomplished on the basis of
traffic. information (vehicle miles) obtained from the Colorado State
Department of Highways.12
An estimated 24.5 million gallons of diesel fuel is burned by buses
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and trucks, operating or passing through the Study Area.
This accounts
. for approximately 40 percent of the total amount of diesel fuel consumed
in the State of Colorado.
The overall estimate as well as the apportion-
ment by counties is based on registration data12 of diesel powered
vehicles in these areas.
Aircraft
Stapleton. Airport in the City of Denver,
Droomfield Airport in
1 ry
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Table 8. AUTOMOBILE REGISTltATION Alf'D GASOLINE SALES
IN DENVER STUDY AREA, 1967
Automobile
Registration
(l,OOO's)
City of Denver 230.6
Adams County 78.6 '"
Arapahoe County 73.0
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Jefferson.County 106.9
Boulder County 53.6
,
Larimer County 35.4
Weld County 36.3'
Total 614.4
Gasoline
Sales
(in million gal.)
403.7
30.7
20.2
20.8
475.4
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'l'able 9. CONSUJI1PTION OF MOTOR FUEL IN THE DENVER
STUDY .AREA, 1967 (millions of. gallons)
Political
subdivision
;.
Gasoline . Diesel fuel
consumption consumption
205.3 5.8
3.4
45.4
6.8 .
..' 1.8
;.
41.9 f~
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16.7
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55.9
City of Denver
Adams Coun ty
ins ide *
outside*
Arapahoe County
inside
outside
Jefferson County
inside
outside
23.6
Boulder County
30.1
1.9
Larimer County
i
Weld County
19.8
20.4
2.2
6.4
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Total
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465.9
24.5
*Refers to portion of county covered by transportation study.
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Jefferson County, and the Buckler Air National Guard Field in Arapahoe
j .
County are the three major airports in the Study Area.
The air traffic
. .
activity by type of operation at both of these locations is summarized in
Table' 10.
Collectively, a total of 742,000 operations (take off and
landing) Here performed during 1967.
According to local FAA representa-
~ives, about 70% of air carrier flights and 50 percent of the military
flights were due to jet powered aircraft.
Railroads
Railroads conSU!:1C about 5.5 million gallons of diesel 011 annually
within the Denver area.
This value was. derived from an estimate made in
19623.
'p'':.''
Emissions from Transportation.Sources
Mobile sources account for 1,600 tons of SOx, 5,000 tons of Particu-
lates, and 576,000 tons of CO in the Study Area.
Approximately 94% of the
sulfur oxides, 72% of the particulates, and 98% of the CO from mobile sources
are attributed to motor vehicles. As shown in Table.ll, the largest
concentration of. pollutants is located in the counties surrounding Denver
and the least concentration in the outlying jurisdictions.
/
. Gasoline powered automobiles and trucks collectively account for 67%,
64%, .and 99% respectively, of the 1,500tons of SOx' 2,600 tons of Parti-:-
culates, and 576,000 tons of CO emitted annually by motor vehicles.
The
remainder is attributed to diesel powered trucks and buses.
The emissions from railroads in the Denver area are negligible.
Most of these emissions are concentrated along the South Platte River.
Aircraft activities account for more than 1,100 tons of particulates
and 11,500 tons of CO annually in the Study Area.
Sulfur oxide ~nissions
~.
are neeligible.
Stapleton Airport, \,'hich is the busiE:st of the three,
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Table 10.
AIR TRAFFIC. ACTIVITY AT STAPLETON, BROOHFIELD, AND BUCKLEY AIRPORTS
CALENDAR YEAR 1967
. Category
of Itinerant Local
Operation Operations Operations
Stapleton Air Carrier 129,141 None
(Denver) '.'
. General Aviation 222,904 90,307
Military 1,598 960
Total 353,643 91,267
,
;
,
Broomfield Air Carrier None None
(Jefferson County)
General Aviation 76,111 180,586
Military 207 58
Total 76,318 180,644
/
Buckley Military (39,596)
(Arapahoe)
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Table 1:. AIR POLLUTANT EMISSIONS FROM TRANSPORTATION
SOURCES:, lQ.9) . (tons/year)
, 1 >/
Political
jurisdiction
Category
SO
~
Adams'
Motor vehicles-gasoline
Motor vehicles-diesel
Railroads
Aircraft
Total
125
70
40
23"5" .
Arapahoe
140
35
10
n
185"
Motor vehicles-gasoline
Motor vehicles~diesel
Railroad?
Aircraft
Total
Boulder
Motor vehicles-gasoline
Motor vehicles~diesel
Railroads
Aircraft
Total
75
40
6
na
120
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Denver
Motor vehicles-gasoline
Motor vehicles~diesel
Railroads
Aircraft
Total
365
115
40
JL.
520
Jefferson
Motor vehi.cles-,gasoline
Motor vehicles~diesel
Railroads
Aircraft
Total
200
60
14
.JL
275
Larimer
Motor vehicles-gasoline
'Motor vehicles-diesel
Ra'ilroads.
Aircraft.
Total
46
45
na .
na
90
Weld
Mbtor vehicles-gasoline
Motor vehicles~diesel
Railroads
Aircraft
Total
43
130
na
na
170
Grand total
1,600
'n=neglig ib1e
na ::: not available
zz
Part.
290
190
100
'580
330
100
27
220
680
175
105
15
na
300
.825
320
100
880
2,125
450
175
40
20
685
110
120
na
na
230
105
355
na
na
460
5,000
I
CO
69,600
100
60
69, BOO
80,200
55
15
1,170
81,400
32,600
60
8
na
32,670
228,000
175 .
60
9,550
2 37 , BO 0
113,400
90
20
800
114,300
2'0, 7 0 0
. 65
na.
na
20,800
19,400
195
na
na
19,600
576,000
-------
contributes 80% of the particulates and 83% of the carbon monoxide from
aircraft operations.
(
; i
Solid - Waste Disuosa1
,
Approximately one million tons of combustible refuse are generated
annually within the Denver Study Area.
The bulk of this refuse is
collected and disposed of by means of modified sanitary land fills, which
.' rarely become a source of air pollution.
According to a survey conducted
by the U.S. Public Health Service in 196713, about 870,00~ tons or 'almost
90 percent, are disposed of in this manner.
The remainder, as shmm in
Table 12, is either composted, incinerated, or burned openly indlli~ps and
on-site.
There are no municipal incinerators !n the Study Area.
Open
burning is prevalent only in the two rural counties -Larimer and Weld,
where some 80,000 tons of refuse are burned annually.
There are no major individual sources of refuse burning in the Study
Area.
The burning of refuse in dumps is spread amoung 20 locations ,,,ith
yearly burning ranging from 30 tons to 3,000 tons.
These, although not
considered as point sources, were identified and located within the grid
system.
The burning of automobile components has been a localized nuisance /
. in the past.
This practice is presently banned and is no longer a problem
in the Study Area.
Emissions from
Solid - Waste Disposal
A total of 50 tons of sax, 1,300 tons of particulates, and 9,800 tons
of CO are emitted annually from solid \"aste disposal practices.
The break-
down of emissions is presented in Table 13.
The majority of emissions are
due to on-site incineration 8n4 backyard burning of refuse in Denver and
., <)
t:' oJ
-------
!"
; i
Table 12. REFUSE DISPOSAL IN DENVER STUDY AREA, 1967 (tons/year)
Combustible.
Poli tical Refuse Incineration Open-Burning
Subdivision Generated ~Hunicipal On-Site Landfills Dumps On-2ite
Denver City .398,000 12,000 386,000
Adams County 129,000 n* 123,006 6,000
Arapahoe County. 108,000 n)~ 107,000 1,000
Boulder County 86,000 600 52,000
Jefferson County 168,000 7,800 160,000 400
.'"
Larimer County 59,000 n* 43,000 8,700 7,100
'rle1d County 65,000 n* 1, .500 n* 64,000
.
Total 1,013,000 20,400 872 ,500 16,100 71,100,
*Negligib1e
".
24
-------
.._-~
-
Table 13. AIR POLLUTANT EHISSIONS FRON SOLID HASTE DISPOSAL - 1967 (tons!jL)
Jurisciction Type of Disposal SOx Part. CO.
Adams Open Burning n* 45 240 "
Incineration n n n
, On~site
I Backyard
I n n n
Incineration n 37 n
Total n 80 240
Arapahoe Open Burning n 2 9
Incineration n n n
On:...site
B.ackyard n - n n
Incineration n n n
Total n "2 9
Bouldcr Open Burnin/; n n n
Incineration n n n
On-site
Backyard n n n
Incineration n 5 60
Total n ,"" 5 60
Denver. Open Burning n n n
"Incineration n n n
On-site
Backyard n n n
Incineration 36 590 1,970
Total 36 590 1,970
Jefferson Open Burning n 3 15
Incineration n n n
On-site
Backyard n n n
Incineration n 16 207
Total n 16 220
/
Larimer Open Burning n 53 710
.Incineration n n n
On-site
Backyard n 70 265
Incineration n n n
.-
Total n 120 980
Held Open Burning n n n
. Incineration n n n
On-site
Backyard 13 477 6,350
Incineration n n n
Total 13 480 6,350
Grand Tc,tal .50 1,300 9,800
N* - nCfoligible
,~ -
" ,
.......
-------
,Weld Counties.
The remainder is divided
among open dumps that. are burned
'intermittently, and onsite disposal sites in the other counties.
, i
Industrial Process Losses
Table 14 presents the number and type of selected manufacturing'
establishments in the Study Area.
Although the Study Area is notably void
of any large heavy industrial complexes, it does contain a significant
"number of industries that generate air pollution emissions from their
. processes.
These include some 30 foundries, a cement plant, 2 refineries,
10 asphalt batching and roo~ing p1~nts, 6 sand and gravel operations, 13
grain storage and processing facilities, a sulfuric acid manufacturing
plant, 6 sugar producing' plants and a number of-miscellaneous operations.
t.Jhere adequate, informat.ion was available, el.1iss~on estimates ,,,ere made and
are included in this survey.
As is the case in any emission inventory,
the lack ofemissionc factors15 for some industrial processes did not allow
a complete estimation of process emissions.
There are 14 iron and steel foundries and 16 non-ferrous foundries
operating in the Study Area.
Based on a 5-day week, an estimated 500 tons
. of metal per day are produced in the ferrous foundries.
The distribution
of production by type.of furnace and air pollution control equipment is
/
summarized in Table 15.'
Seven asphalt batching plants produce approximately 890,000 tons of
asphalt per year.
The plants range in size from 50,000 to 400,000 tons per
year.
All of the plants are equipped with air pollution cont!ol devices,
primarily cyclone separators and scrubbers.
Three asphalt roofing plants
bave a collective production rate of 37,000 tons per year.
The t\'l0 largest
plants (31,000 tons per year) are equipped ,wit!l scrubbers, whereas the
2G
-------
10- -.- 0
1
0'
: 1
Table 14. SELECTED }V~NUFACTURING ESTABLISill1ENTS14
IN THE DElNER STUDY AREA. 1966
Type of Establishment
. Number
Fabricated Structural & ~fetal Products
Nisce11ancous l'Jachinery
Textiles
Concrete; Gypsum, & Clay Products
Instrument Hanufacture
Food & Kindred Product~
Chemicals 0 .
Paper.Products
Glass Products
Roofing & Paving
Stone Products
Paint Manufacture
Printing & Coating
Uood Products, Furniture
Miscellaneous Manufacturing
170
280
100
110
68
215
58
36
22
9
16
-12
280
160
180
,,,
. '''''",
I 0
/
27
-------
"
,. i
Table l5~. PRODUCTION AND EQUIPME~7 IN FERROUS FOUNDRIES, 1967
Production
Furnace Rate Air Pollution
Type Number (tons/day) Control Equipment
Electric arc 4 66 all equipped w/baghouse
Open hearth 1 2 N. A.
Induction 9 270 no controls
Elec. induction 1 31 N. A.
Cupola 1 80 ..,,~, baghouse & afterburner
3 40 no controls
Other 3 6 . no controls
Total 22 495
1 ;
00
"
.. - .
28
-------
smallest is uncontrolled.
(
A portland cement plant lobated in Larimer County produces 1,430
tons of cement per day by the dry process.
The rotary driers are equipped
with ,fabric baghouses and the clinker kilns are equipped ,.,ith cyclones and
electrostatic precipitators.
Six sand and gravel operations produce a total of 1,300 tons of
aggrcgate per day.
Much of the crushing, screening aDd handling activi-
ties are controlled by baghouse and cyclone collectors.
T\-1O petroleum refineries and a small re-refining operation are
located in Adams County.
The two refineries have a collective throughput
rate of 33,000 barrels per day of sweet crude and 3,500 barrels per day
of asphalt crude.
The sulfur content of the crude oil is approximately
0.3%.
, .
The operation at both of these plants includes vacuum di.stillation,
catalytic cracking, and reforming.
The comb-ined catalytic cracking rate
is about 14,800 barrels per day fresh feed. One of these uses a Thermofor
unit ",hereas the other employs a fluid catalytic cracker.
The Denver Metropolitan Area is a major grain handling, processing
and storage center.
There are 13 major grain handling and storage
,,'
establishments located in the Study Area.
In addition to handling and
,~toring, five of these establishments have milling facilities.
Table 16
presents the annual storage as 'veIl as milling capacities by type of grain.
Hore than 50 million bushels of grain, primarily corns miio and wheat,
were handled during 1967.
An estimated 310,000 tons of ,.,heat, \'Jere milled
in the Denver area during 1967~
There is a variety of chemical plants in the Study Area.
Among these
<:r~--
are producers of sulfuric acid" aIT~onium sulfatet phosphate and nitrate
fertilizers, and others.
~ chemical plant located within the City of Denver
.~) g
-------
(.
; i
Table 16,- STORAGE AND HILLING OF GRAIN IN THE STUDY AREA, 1967
Storage
.capacity
Type (million bu/year)
Corn 18.0
Milo 18.0
Hheat 10.4
Barley 1.6
Oats 0.3 . -,'
Rice 1.0
1.0 ..
Rye
A1f.a1fa
-.
Total 50.3
'J 0
t) .
. Milling
(103 tons/year)
310.0.
7.5
317.5
i.
t
f
i
,
i
r
t
I
!
.
.
(
i
I-
I
L
.
f~
i
I
f:
., )
t
1
r.
-------
produces 100 tons/day of sulfur~c acid, 20-30 tons per day of aiuminum
sulfate and 10-15 tons per day of nitric acid.
A fertilizer pla~t in
Boulder operates for a period of 4 months producing 50 tons per day.
Among the other types of industries located in the Study Area are
six beet sugar plants, several lumber and paperboard Dills, and numerous
fabricated metal shops.
The six beet sugar plants located in Adams,
Larimer, and Held Counties process more than 8,500 tons per day during
seasonal peak.
There are numerous establishments in the Study Area that manufacture
or utilize organic solvents in their operations.
These include dry clean-
-,'
ing plants, paint shops, wood preservative operations, and printing and
publishing establishments.
The hydrocarbons generated by these establish-
ments have not been included in this study,
Emissions from Industrial Process Losses
Air pollutants from industrial process losses account for 8,800 tons
of the SOx, 8,900 tons of the particulates, and 24,700 tons of the CO emitt-
ed annually in the Study Area.
The breakdovm of emissions by industry
. types is shown in Table 17.
;'
The two petroleum refineries in the Study Area generate 77% of the
sulfur oxides emitted by process loss sources.
Approximately four-fifths
of this is due to the burning of plant fuel containing hydrogen sulfide.
Two chemical plants producing sulfur and sulfuric-acid account for the
remainder of the SOx emissions.
The storage and processing of grain in the Study Area account for 57%
of the particulates from process losses.
Although most of the plants are
equipped with cyclones, fine particles are released into the atmosphere.
The remainder of the particulate e!:1ission.s Clre divided among the other
-------
(
'i
Table17.AIR POLLUTANT EMISSIONS FROM PROCESS LOSS
SOURCES IN THE STUDY AREA, 1967 (tons/year)
Type of Industry SOx Part. CO
Asphalt batching plants, 80
Asphalt roofing plants 150
Chemical plants 2,000
Cement manufacturers 120
Ferrous foundries 230 1,280
,.,
Grain storage & processing 5,060
I ' Non-ferrous fo~ndries 20
I Petroleum refining 6,830 260 23,400,
[
I Sand &, gravel operations 1 ,.14 0
Other 1,840
Total 8,800 8,900 24,700
/
, .
3c
(.,
-------
'. "-----~
industries in the Study Area.
~ .
The, catalytic craclcing uni~s in the petroleum refineries produce 95%
. i
of the carbo~ monoxid~ 5enerated from industrial process losses. Gray
iron cupolas in the ferrous foundries account for the remaining 5%
of the
CO emissions.
EMISSIONS BY GRIDS
For the purpose of nJodeling the air pollutant emissions in the Study
Area, the resulting emissions are apportioned on the gri~ coordina'te
system.
Sixteen point sources of SOx, 15 point sources of particulates,
and 2 point sources of CO are identified individually ,~ith respect to
location and' emissions.
The emissions for SOX) ,particulates , and CO are
presented in Tables l8A and l8B as average summer day, average winter day,
U.----_.._._-
. .. _.- ----_M. .----:....-
. -. -.. ------
and average annual day estima'tes.
.-.-----""""'---~...-
---'~,......~-~
. r..
, The daily emission rates were obtained by dividing yearly totals by~.
~_. ----.-.... ,'-----"-"--- . -..- ---------- - ---.--... -... '------""-----'-- --"'-'--- _......--.--- .
appropriate operating day values.
Fuel combustion was aivided into space
heating and constant emissions.
Space heating was apportioned on the basis
of degree day variations.
-Residential emissions were assumed to occur through-
out the year.
Unless specific data was obtained from individual sources,
industrial, commercial, and institutional sources were assumed to operat~
from 250 to 310 days per year.
Mobile sources and' solid waste disposal sources
were assumed to be spread thoughout the year.
The seasonal variations in
motor vel11.cle emission<;'vere based on average daily traffic factors.
p~'
33
r
-------
'I
,I
,)
"
J
I
II
"
i:
-- -.... - -. --.
34
. ~. '1...'.- .... .
. ...~~. .......~"'- - -
,"
'i
KEY TO DIISSION TABLES
".'
1)
Area - Square Kilometers
2) . SOx - Sulfur Oxi<;les
3)
4)
Part. - Particulates
CO - Carbon Monoxide
5)
6)
S - Average Summer Day
W -..Average Hinter Day
7)
A - Average Day
,;
-------
i ---- --- ------
- - - -- - -
I'
i ~
II
Ii
j Table 18A. Sill-lN/\RY OF EHISSIONS FROH AREA SOURCES BY SEASON
.~ :-
. ; i
.. Grid Area SOx Ton/Day Ton/Day CO Ton/Day
j Part.
Sq.~. S \01 A S W A S W A.
j
.~ 1 2,741 .0 .0 .0 .01 .01 .01 .69 ,57 .61
1
i 2 2,741 .47 1.23 .85 2.03 3.88 2.96 44. 7/f 36.56 39.24
3 2,741 .16 .42 .29 .63 .89 .76 12.28 10.52 11.10
t 4 2,741 .01 .03 .02 .16 .20 .18 3.61 3.03 3.22
5 171.4 .0 .02 .01 .08 .12 .10 1.36 1.11 1.19
~ 6 171.4 .0 .0 ' .0 .02 .02 .02 1. 31 1.06 1.14
':i 7 171.4 .10 .40 .25 .45 1.32 .89 21. 27 17.49 18.73
> 8 171.4 .39 .65 .52 .47 .77 .62 8.25 7.0,8 7.46
'
J
'! 9 171.4 .48 1.33 .91 2.09 4.04 3.07 39.37 33.51 35.43
:i 10 171. 4 .08 .08 .08 .08 .08 ~08 1. 25 1.01 1.09
11 171.4 .0 .02 .01 .0/1 .08 .06 4.11 3.32 3.58
.. 12 171.4 .47 1.44 .96 1.40 4.38 51. 50 41. 67 44.89
2.90
13 171.4 .49 1.11 ~80 2.23 4..10 3.17 22.11 18.17 19.46
14 171.4 .08 .20 .14 .41 .69 .55 8.57 7.40 7.78
: 15 171.4 .05 .07 .06 .16 .20 .' .18 2.67 2.31 2.43
,-
[i 16 171.4 .0 '.0 .0 .19 .19 ~19 2.24 2.00 2.08
I, 17 171.4 .0 .0 .0 .04 .04 .04 '5.31 4.29 4.62
11 18 42.84 .82 1.24 1.03 1.14 1.38 1.26 29.64 23.97 25.83
I; 19 42.84 .21 .43 .32 .55 1.17 .86 29.75 24.47 26.20
" 20 42.84 .04 .04 .04 .10 .10 .10 5.77 4.67 5.03
,
j 21 42.84 .07 .07 . .07 .27 .27 .27 12.68 10.25 11.05
.
'I 22 42.84 '.27 .63 .45 .73 1".92 1.33 1~9 .if3 40.01 43.13
~
[.1 23 171.4 .0 .0 .0 . . O!~ .04 .04 .78 .65 .69
" 24 171.4 .0 - -.0 .0 ' .11 .11 .11. 1.25 1.12 1.16
I! '
25 171.4 .0: ..0 .0 .0 ~ .O .0. ' ,If 6 .37 .40
, . -
26 171.4 .07 .07 .07 .J, .15 .15 .15 23.64 19.09 20.58
I .27 42.84 .36 .60 .48 .71 1.58 'h 1.15 61. 09 49.34 53.19
1 28 42.84 .04 .04 .04 .08 .08 .98 16.20 i 13.08 14.10
j 29 171.4 .0 .0 .0 .04 .04 .04 5.74 4.64 5.00
Ii 30 171.4 .0 .0 .0 .04 .04 .04 5.74 4. 6/~ .5 .00
I~ 31 171.4 .0 .0 .0 .05 .05 .05 5.77 4.67 5.03
~ 32 171.4 .01 .01 .01 .04 .04 ;04 4.08 3.29 3.55
33 171.4 ' .0 .0 . .0 .01 .01 .01. 1.63 1.32 1.42
~ 34 42.84 .05 .05 .05 .10 .10 .10 19.02 15.36 16.56
35 42.84 .12 .16 .14 .27 .43 .35 38.10 30.78 33.18
,; 36 42.84 .1I~ .18 .16 .95 1.03 .99 44.59 36;01 38.82
37 42.84 .20 .26 .23 .83 .97 .90 33.69 27.27 29.37
11 38 42.84 .16 .50 .33 .28 1.43 .86 If 0 . 37 32.68 35.20
39 10.71 .05 .53 .29 .62 .94 .78 13.58 10.98 11. 83
1 40 10.71 .07 .65 .36 .16 2.17 1~17 20.99 17 .01 18.31
" 41 10.71 .10 .20. .15 .20 .28 .24 12.19 9.85 10.62
"
['; 42 10.71 .12 .26 .19 .36 .80 .58 59.76 l.8. 31 52.06
II 43 10.71 ,09 .~15 ' .12 1.27 1.41 1.34 15.09 12.19 13.14
. 44 10.71 .29 .43 .36 3.30 3.66 3,1.8 50. /.3 38.98' 42.73
j 45 10.71 .11 .17 .1.4 1.63 1.77 1. 70 15.()7 12.77 13.72
46 10.71 .15 .l~1 .28 3.08 3.91 3.50 59.80 48.35 52.10
" -
(I ;)
-------
(Continuation of Table 18A)
!
Grid Area SO.., Ton/Day ; r Part. Ton/Day CO Ton/Day
" Sq. Km. S H A S W A S t.J' ,A
47 10.71 .08 .16 .12 .79 1.03 .91 20.70 16.73 18.03
48 10.71 .15 .2 J. .18 .48 6 -, .58 23.94 19.37 20.87
. b
49 10.71 .02 .02 .02 .02 .02 .02 3.73 3.01 3.25
50 10.71, .01 .01 .01 2.45 2.45 2.45 32.06 30.93 31. 30
51 171.1. .12 .20 .16 .40 ,.64 .52 26.12 21.11 22.75
.52 42.84 .18 .92 , .55 .19 3.15 1.68 33.58 27.27 29.34
53 10.71 .10 .70 ,L~O .20, 2.49 1.35 28.16 22.79 21. .55
54 10.71 .05 .23 .14 .10 ..64 .37 19.07 15.41 16.61
55 10.71 .09 .31 .20 1.02 1.66 1.34 60.28 48.83 52.58
56 10.71 .08 .20 .14 1.39 1. 79 1.59 36.88 29.83 32.14
57 10.71 .31 1.09 .70 .81 3.28 ' 2.05 111.57 90.19 97.19
58 10.71 .21 .39 .30 1. 76 2.28 2.02 59.83 48.38 52.13
59 10.71 .13 .55 .34 .33 1. 78 1.06 59.77 48.32 52.07
60 10.71 .06 .18 .12 .20 .60 .40 31.90 25.82 27.81
61 10.71 .09 .29 .19 .23 .99' .61 36.89 29.81. 32.15
62 10.71 .04 .06 .05 .06 .22 .14 15.79 12.75 13,.75
63 10.71 .32 64 .48 .09 .53 .31 19.72 15.94 17.18
64 10.71 ..04 .04 .04 .01 .01 ";01 3.91 3.15 3.40'
65 42.84 .22 . 40 .31 .19 ' .67 .43 37.37 30.19 32.54
66 42.84 .01 .01 .01 .72 .72 .72 23.31 19.44 20.71
67 42 .8'. .07 .07 .07 .1'0 '.16 .13 16.29 13 . 16 14.19
68 42.84 .27 .35 .31 .74 1.06 .90 1.1. 77 33.81 36.42
69 42.84 .38 .60 .49 .97 2.02 1.50 53.43 43.18 46.54
70 42. 8'{ .15 .15 .15 .45 ,.55 .50 31. 96 26.63 28.38
71 42,84 .05 ,05 .05 .05 ,05 .05' 13.21 1.0.67 11.50
72 42,84 ,0 .0 ,0 .01 .01 .01 2.87 2.32 2.50
73 42.84 .05 .05 .05 .08 .08 .08 16.20 13.08 14.10
7'~ 42.84 .13 .15 .14 .27 .39 .33 19.28 15.57 16.79
75 42.84 .08 .08 .08 .10 .16 .13 16.40 13.25 1/..28
76 42.84 .04 .Oft .04 .04 .06 .05 9.17' 7.1.0 7'.98
77 42.84 .02 '.02 .02 .05 .05 .05 4.08 3.29 3.55
78 42.84 a na na na na na na na na
n
, '79 42.84 na 11a na na ~a na, na " na na
80 42.84 na na na ', na na na na na na
81 171.4 .04 .04 .04 .08 .08 .08 14.91 12.01. 12.98
na = not available (Douglas County)
r
36
-------
: i
Table laB. SUHMARY OF EMISSIONS FROM POINT SOURCES BY SEASON
Type of P1a~t Grid SOx Ton/Day Part. Ton/Day CO Ton/Day
S hI A S H A S i.; .'
,~
Chemical Plant 56 4.49 4.49 4.49
,
Chemic~l Plant 58 3.60 3.60 3.60
Industry 22 0.81 1..20 1.01 4.14 5.70 4.90
Grain Elevator 41 7.70 7.70 7.70
Grain Elevator 47 2.42 2.42 2.42
Industry 13 1.94 2.88 2.41 1.81 2~46 2.18
Industry 21 neg. 4.00 1.43 neg. 10.00 3.60
Industry 9 neg. 2.44 0.89 neg. 6.45 2.32
Federal Facility 51 2.20 2.20 2.20
Feder~l Facility 63 2.11 6.30 4.18
Industry 7 neg. 4.45 1.59 neg. .3.06 1.10
Industry 9 neg. 2.67 0.97 neg. 3.78 1.36
Federal Facility 52 0.05 . 1.59 0.80 0.19 7.53 3.78
./
Power Plant 55 1.10. 6.20 2.95 0.55 2.15 1.15
PO\ver Plant 68 . 0.53 . 8.92 4.88 0.55 3.23 1.95
Power Plant 45 16.80 23.20 21.50 6.03 8.35 7.73
Power Plant .13 11.85 13.50 11. 60 4.28 4.88 4.18
Power Plant 2 1.30 1.30 1.30
Refinery /,5 16.91 16.91 16.91 27.20 27.20 2i.20
Refinery 45 1.80 1.80 1.80 37.00 37.00 3i.C
" ,....
J i
-------
._,-'..' . ~
.)'Q
"
REFERENCES
.. .,.' ,"-..
; I
1.
Ozolins, Guntis, and Smith, Raymond:
Rapid Survey Technique for
Estimating Community Air Pollution Emis3ions, DHEH, PIlS, October, 1966.
2.
Colorado Hunicipalities, 1967, Colorado Division of Accounts and Control.
3.
Cooperative Study by
Dobler, Leonard A., and Palomba, Joseph, Jr.:
the Denver Hetropolitan,Air Pollution Study Group, January, 1967 -
April, 1963.
4.
Fuels and Electric Energy Consumed in Hanufacturing Industries:
1962,
1963 Census of Nanufacturers, U.S. Department of Commerce, July, 1964.
5.
Distillate and Residual Fuel Oil Consumed by Nanufacturing Industries:
."
1962, 1963 Census of }lanufacturers, U.S. Department of Commerce,
NoveI'!1ber, . 196} .
6.
Communications from the Public Service Company of Colorado to Denver
City and County Air Pollution Section.
7.
Steam Electric Plant Factorsi 1966, National Coal Association, August,
1967.
8.
Personal Communication from Colorado Petroleum Council.
9.
U.S. Census of Housing 1960, Colorado, U.S. Department of Con~erce, /
Bureau of the Census, Report HC . (1) - 7, December, 1961.
10.
Personal Communication from the Imperial Coal Company, Colovl}'o Coal
Company and the Clayton Coal Company to the Colorado Department of
Public Health.
11.
Retail Trade - Ga~oline Service Stations and Liquefied Petroleum Gas
Dealers, U.S. Census of Business, U.S. Department of Con~erce,
January, 1967.
12.
Personal Commun:!.cation from the Colorado Department of IUgln'laYs,
PlanninB and Research Division to National Air Pollution Control Adrnl~:-
str;]ti.on.
-------
...' .. ~._-- .. -..
. 14.
i
13.
Community Description, Facility Investigation, and Land Disposal Site
J
Investigation Reports of the U.S. DHEW Solid ~aste Program.
Directory of Colorado ~Janufacturers, 1966, University of Colorado,
Business Research Division of the School of Business, 1967.
15.
Duprey, Robert L.:
Compilation of Air Pollutant Emission Factors,
DHEH, PHS, 1968.
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