United States
Environmental Protection
Agency
Hazardous Waste Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-85/057 July 1985
l\\
Project Summary
Evaluation of Air Emissions
from Hazardous Waste Treat-
ment Storage, and Disposal
Facilities
W. D. Balfour, R. G. Wetherold, and D. L. Lewis
This study examines the fugitive air
emissions from landfills, surface im-
poundments, storage tanks, containers
(drums), solvent recovery processes,
and land treatment technologies at
Hazardous Waste Disposal Facilities
(HWDFs). The main objective was to de-
velop and demonstrate techniques for
determining air emissions from the
above sources. Various predictive mod-
els for estimating air emissions exist for
some of these sources. These models
have been identified and evaluated for
applicability to select HWDFs. Sam-
pling approaches have been identified
for measuring the air emissions from
these different operations. Procedures
for the collection and qualitative and
quantitative analysis of the air samples
and the liquid and solid samples taken
in conjunction with the air samples
have also been developed. The result-
ing analytical data have provided gen-
eral information on the level of air emis-
sions from the sources studied. This
document summarizes the findings
from each of four HWDFs tested, com-
paring and contrasting the measured
and predicted emission results and the
experiences gained in using the various
sampling approaches.
This Project Summary was devel-
oped by EPA's Hazardous Waste Engi-
neering Research Laboratory, Cincin-
nati, OH, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Introduction
The Office of Solid Waste (OSW) is
required, under Executive Order 12291,
to conduct a Regulatory Impact Analy-
sis (RIA) that will examine costs and
benefits for various alternatives to con-
trol air emissions from the treatment,
storage, and disposal operations at haz-
ardous waste disposal facilities
(HWDFs). This study has examined the
fugitive air emissions from landfills,
surface impoundments, storage tanks,
containers (drums), solvent recovery
processes, and land treatment tech-
nologies at HWDFs.
The main objective of this study was
to develop and demonstrate techniques
for determining air emissions from the
above HWDF technologies (sources).
Various predictive models for estimat-
ing air emissions exist for some of these
sources. These models have been iden-
tified and evaluated for applicability to
select HWDFs. Sampling approaches
have been identified for measuring the
air emissions from these treatment,
storage, and disposal operations. Pro-
cedures for the collection and qualita-
tive and quantitative analysis of the air
samples and the liquid and solid sam-
ples taken in conjunction with the air
samples have been developed. The
resulting analytical data have provided
general information on the level of air
emissions from the sources studied.
Specific information has been pre-
sented in separate Data Volumes for
each of the four sites tested. This docu-
ment summarizes the findings from
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each of these sites, comparing and con-
trasting the measured and predicted
emission results and the experiences
gained in using the various sampling
approaches.
Predictive Models for Compari-
son to Air Emission Measure-
ments
Reviews of models for estimating air
emissions from hazardous waste treat-
ment, storage, and disposal facilities
have been provided to EPA by Radian
and GCA. GCA has recommended those
models shown in Table 1 for use in pre-
dicting emissions from various treat-
ment, storage, and disposal facilities.
Data were collected at the sites for input
to the models. Where possible, mea-
sured values were used as input. Where
measured values were not possible, in-
put values were obtained from records,
literature values, engineering esti-
mates, etc.
Sampling Approaches for Mea-
suring Air Emissions
The sampling approaches for mea-
suring air emissions from treatment,
storage, and disposal facilities (TSDFs)
include:
emission isolation flux chamber,
vent sampling,
concentration-profile,
transect technique, and
mass balance.
Table 2 presents the sampling ap-
proaches identified as applicable to var-
ious treatment, storage, and disposal
facilities.
Sampling Sites
Six sites were investigated during an
initial pretest site survey. The survey
was designed to select those sites that
had TSDFs most suitable for testing.
The recommendations for field testing
and results from the initial sampling
and analytical efforts are found in the
pretest site survey report. Four of these
six sites were tested, including Sites 2,
4, 5, and 6.
Testing Program
The field testing conducted at the
sites is shown in Table 3. The field test-
ing was performed during the following
periods during the Fall of 1983.
Site 5 - September 30 - October 11,
Site 4 - October 11 and 12,
Site 6 - October 24-28, and
Site 2 - November 14-18.
A systems and performance audit of the
Table 1. Recommended Air Emissions Models for Hazardous Waste Disposal Facilities
Source Model(s)
Landfill
Landtreatment
Surface Impoundment
Open Tank
Storage Pile
Fixed Roof Tanks
Floating Roof Tanks
Farmer, et al (1978) - for Covered Landfills
Thibodeaux (1980) - Landfill Equation-without internal
gas generation
Thibodeaux (1981) - Landfill Equation-with internal
gas generation
Hartley Model (1969)
Thibodeaux-Hwang (1982)
Mackay and Leinonen (1975) - Unsteady-State Predic-
tive Model for Nonaerated Surface Impoundments
Thibodeaux, Parker, and Heck (1981) - Steady-State
Predictive Model for Nonaerated and Aerated Sur-
face Impoundments
Thibodeaux (1980) - Aerated Surface Impoundment
(ASI) Model
Hwang (1970) - Activated Sludge Surface Aeration
(ASSA) Model
Freeman (1980) - Diffused Air Activated Sludge (DASS)
Model
Midwest Research Institute Emission Factor Equations
for Storage Piles
API (1962), modified by TRW/EPA, Fixed Roof Tank
Breathing Losses
API (1962) - Fixed Roof Tank Working Losses
API (1980) - Evaporation Loss from External Floating
Roof Tanks
EPA/API (1981) - Standing Storage Losses from Exter-
nal Floating Roof Tanks
EPA/API (1981) - Standing Storage Losses from Inter-
nal Floating Roof Tanks
on-site sampling and analytical activi-
ties was conducted by Radian's Quality
Assurance Coordinator on October 5-7.
Conclusions
The field testing performed in this
program has provided data on the air
emission rates from a variety of sources
within hazardous waste treatment, stor-
age, and disposal facilities (TSDFs). Air
emission rates were measured using
various approaches and predicted using
existing models. Neither the measure-
ment approaches nor the predictive
models have been validated, and as
such, this program represents a demon-
stration of these approaches for mea-
suring/modeling erpissions from TSDF
sources. The measured and predicted
emission rates have been compared
throughout this report as a relative com-
parison only. The accuracy of the mea-
sured and the predictive procedures are
not established. The experiences
gained during this program should,
however, provide a basis for future field
testing of TSDFs.
A summary of the results of the emis-
sion rate measurements from the vari-
ous TSDFs tested is given in Table 4.
Only the total nonmethane hydrocar-
bon (TNMHC) emissions are included in
this table. Results are provided for both
the entire surface area (kg-C/day) and
per unit area (kg-C/hectare-day). The
emission rates presented in the table
represent an average of all the measure-
ments for a given source. The measure-
ments were made over a relatively short
period of time and under specific pro-
cess operating and meteorological con-
ditions. For these reasons, caution
should be used in attempting to extrap-
olate these data to sources at other
TSDFs, or for longer time periods (i.e.,
annual averages).
The highest emissions measured at
an active landfill were encountered dur-
ing active dumping of the waste (23.1
kg-C/day). Emission rates were lower
(1-10 kg-C/day) in areas of the landfills
which did not have active dumping con-
current with the measurements. All but
one of the landfills tested were very
large with multiple cells. Because of the
large exposed surface areas, the emis-
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sions for the total source were similar in
magnitude to the surface impound-
ments. No measurable emissions were
detected through the cover of the inac-
tive landfills tested. Both inactive land-
fills did however have vents from which
emissions were detected (<0.01 kg-
C/day). Emissions from the vents were
not constant, rather they occurred as
puffs with no specific frequency of oc-
currence.
A variety of surface impoundments
were tested, including small surface
area receiving ponds (high liquid con-
centrations) and large surface area pol-
ishing ponds (now liquid concentra-
tions). As expected, the emissions from
the receiving ponds were higher (order
of magnitude) than the polishing ponds
on a per surface area basis. Emissions
from the total sources were more simi-
Table 2. Summary of Emission Measurement Approaches for Selected Activities within a Hazardous Waste Disposal Facility
Comments
Activity
Emission Measurement
Approach3
Treatment Plants
1) Physical, biological and/or chemical
treatment units, including continuous
mixing in open tanks
2) Spraying/aeration and spray irrigation
3) Distillation and cracking/refining
Storage
4) Open tanks
5) Surface impoundments
6) Evaporation ponds or tanks
(unheated and heated)
7) Drum recycling operations
8) Spent drum storage
Disposal Facilities
9) Landfills (active and inactive)
W) Landtreatment
Fugitive Sources
71) Vacuum pumps used on tank trucks
Emission isolation flux chamber
Mass balance
Transect technique
Vent sampling
Transect technique
Vent sampling
See 1) above
Concentration-profile technique
Transect technique
Emission isolation flux chamber
Mass balance
See 1) above
Transect technique
Emission isolation flux chamber
See 7) above
Transect technique
Emission isolation flux chamber
Vent sampling
Emission isolation flux chamber
Mass balance
Transect technique
Vent sampling
Transect technique
Open tanks; little or no surface disturb-
ance
Batch process or steady-state operation/
process
Requires minimal interferences from other
emission sources; applicable when
surface is highly agitated
Closed tanks
Requires minimal interferences from other
sources; must consider aerosal vs. vapor
during sampling collection
Must meet criteria for the micro-
meteorological model
Requires minimal interferences from other
emission sources; not applicable to large
impoundments
Small surface impoundments and/or
minimal surface disturbances
Batch process or steady-state operation/
process
Requires minimal interferences from other
emission sources
Bagging of single drums only
Requires minimal interferences from other
emission sources
Covered landfill only
Covered landfill with gas collection system
Requires some knowledge of biodegrada-
tion rate
Requires minimal interferences from other
emission sources
Requires minimal interferences from other
emission sources
3Description of emission measurement approaches:
Emission isolation flux chamber - direct emission measurement, no interference from other emission sources.
Mass balance - indirect emission measurement based upon difference in bulk component concentrations.
Transect technique - indirect emission measurement based upon ambient concentrations downwind from source, other emission sources
can interfere with measurements.
Vent sampling - direct emission measurement, no interferences from other emission sources.
Concentration-profile technique - indirect emission measurement based upon ambient concentrations immediately above surface,
minimal interference from other emission sources as long as a concentration profile can be measured.
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Table 3.
Site
2
4
5
Summary of Field Testing
Source
Landfill (active)
Landtreatment
Chemical Landfill D
(active)
Chemical Landfill C
(inactive)
Wastewater treatment.
Reducing Lagoon 1
Wastewater treatment,
Oxiriirinn 1 aannn 2
Performed
Sampling Approach
Transect technique and
Emission isolation flux
chamber
Emission isolation flux
chamber and
Concentration-profile
technioue
Flux chamber
Flux chamber
Flux chamber
Flux chamber
Model
No specific model
applicable
Thibodeaux-Hwang
(1982), Hartley
(1969)
No specific model
applicable
No specific model
applicable
Thibodeaux, Parker
and Heck (1983)
Thibodeaux, Parker
anri Her.k /IflR.lt
ity control procedures were readily per-
formed. The statistical sampling ap-
proach appears suited to the sampled
ponds, landfarm, and some landfills.
However, certain of the landfills were
quite large and heterogeneous in na-
ture, making the overall representative-
ness of the limited data obtained sus-
pect in these cases. In general, very
good correlations were observed be-
tween all components detected from
the chamber and the volatile compo-
nents in the corresponding liquids and
solids (waste). The variability in the
emission rates determined using the
flux chamber was typically much less
than the transect, concentration-profile,
or predicted emission rates.
Wastewater treatment,
Holding Pond 6
Hazardous, non-hazardous
drum storage building
Chemical Landfill 10
(active)
Chemical Landfill 7
(inactive)
Distillation Process
Closed Tanks (vented)
Drum Storage and
Handling3
Spray Evaporation Pondb
Concentration-profile
Flux chamber
Vent sampling
Transect technique
Flux chamber
Flux chamber
Vent sampling
Mass balance
Vent sampling
Transect technique
Transect technique
Thibodeaux, Parker
and Heck (1983)
No specific model
applicable
Individual cells,
Farmer, et al (1978)
Thibodeaux (1980)
No specific model
applicable
No specific model
applicable
API/EPA (1962)
No specific model
applicable
No specific model
applicable
3Testing scheduled, but not performed due to meteorological conditions; qualitative data
obtained.
bLimited testing performed due to meteorological conditions.
lar due to the differences in size of the
ponds, with the receiving ponds (1-7 kg-
C/day) being somewhat higher than the
polishing ponds (0.4-1.4 kg-C/day).
The highest emissions measured
were for the land treatment of oily
wastes. Depending on the approach
used for making the measurement and
the time that the measurement was
made after initial spreading of the
waste, the emission rates ranged from
3-60 kg-C/day. The waste was surface
spread and included daily tilling. Emis-
sions tended to decrease rapidly follow-
ing the initial application and to in-
crease slightly with each day's tilling.
Emissions during solvent recovery
operations for 1,1,1-trichloroethane and
methylethylketone (MEK) were at nomi-
nally 1% of the throughput for the distil-
lation process. Losses (emissions) dur-
ing washing of the 1,1,1-trichloroethane
were substantially greater (16.7%).
Emissions from a drum storage build-
ing were measured at 0.2 kg-C/day. Sur-
veys around outside drum storage
areas showed measurable TNMHC con-
centrations, but no emission rates were
determined. Measurements of the
breathing losses (emissions) from
fixed-roof storage tanks were at-
tempted, but no measurable flow from
the vents could be detected.
A number of field sampling tech-
niques were used in this study includ-
ing:
emission isolation flux chamber
transect technique
concentration-profile technique
vent sampling
mass balance
As a result of the experience gained in
using these techniques, several general
statements on the use and limitations of
each of the approaches can be made.
The emission isolation flux chamber
technique was simple and straight-
forward to execute in the field. No spe-
cific meteorological conditions pre-
vented sampling, with the exception of
high winds during tethered operation at
some ponds. Field calibration and qual-
The transect technique required more
instrumentation and was more labor in-
tensive than the emission isolation flux
chamber. The transect technique is very
dependent upon and very vulnerable to
ambient meteorological conditions, the
physical surroundings about the mea-
sured source, and the configuration of
the source itself. During the testing peri-
ods, testing was often prevented due to
unacceptable atmospheric stabilities,
high/low wind speeds, variable wind di-
rection, and wrong wind direction.
Transect testing was precluded at some
sites because of the proximity of obsta-
cles that produced air turbulence and
prevented proper plume formation.
These experiences emphasize the ex-
tent to which meteorological depen-
dence can escalate the cost and ability
of obtaining emission data using the
transect technique. In general, the un-
certainty associated with the emission
rates estimated by the transect tech-
nique are greater than those measured
by other methods.
The concentration-profile technique
required the most instrumentation and
was the most labor intensive of the
three sampling approaches. It too is de-
pendent on ambient meteorological
conditions and physical configuration
of the source. During the field testing,
unsatisfactory meteorological condi-
tions resulted in several days' delay
and, in some cases, samples of
questionable validity. Both the
concentration-profile and transect tech-
niques require analysis of air samples
which are at least an order of magnitude
more dilute than corresponding flux
chamber samples. This fact impacts the
analytical procedures which can be
used with these approaches and the
level of compounds which may be de-
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tected. The method is also limited to
flat, relatively large area sources. The
variability in the emission rates deter-
mined using the concentration-profile
technique was typically greater than
with the flux chamber, but better than
the transect technique.
It is generally expected that the flux
chamber will result in lower measured
emission rate than the concentration-
profile technique, due to the absence of
wind effects in the flux chamber. In
comparing the emission rates deter-
mined by both methods at the landtreat-
ment area. Site 2, the concentration-
profile values were indeed higher than
the flux chamber values. The difference,
however, may have also been due in
part to the time dependence of the
emission rates from the landtreatment
area and the fact that the concentration-
profile measurements were made fol-
lowing tilling (which is expected to tem-
porarily increase the emission rate).
Table 4. Emission Rates of Total Nonmethane Hydrocarbons from TSDF
Sources Measured Using Various Sampling Approaches
Emission Rate
TSDF Source
Sampling Approach (Kg-C/hectare-day) (Kg-C/day)
Active Landfill
Site 5-Landfill 10
Site 4-Landfill D
Site 2-Landfill Q
Inactive Landfill
Site 5-Landfill 7
Site 4-Landfill C
Surface Impoundments
Site 5-Lagoon 1
Site 5-Lagoon 2
Site 5-Pond 6
Site 6-Pond 3
Solvent Recovery
Site 6-1,1,1-Trichloroethane
Site 6-MEK
Landtreatment
Site 2-Landtreatment
Drum Storage Building
Site 5
Storage Tanks
Site 6
Transect Technique 3.8, 9.2a
Emission Isolation Flux 4.5b, 13b
Chamber
Emission Isolation Flux 4.1b
Chamber
Emission Isolation Flux 0.8b
Chamber
Emission Isolation Flux
Chamber
Vent Sampling
Emission Isolation Flux
Chamber
Vent Sampling
Emission Isolation Flux 10
Chamber
Emission Isolation Flux 49
Chamber
Emission Isolation Flux 2.7
Chamber
Concentration-Profile 0.8
Transect Technique 54d
Mass Balance
Mass Balance
e, 16.7%f
Emission Isolation Flux 626-539
Chamber
Concentration-Profile 1080-831h
Vent Sampling
Vent Sampling
9.5, 23.1
1.1b,8.2b
1.6b
0.015b
<0.01
<0.001
1.4
7.1
1.4
0.4
2.7d
35-38
60.5-46.5"
0.2
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between predicted and measured emis-
sion rates in half of the cases examined
for Lagoon 1. In all other cases, the pre-
dicted rate was greater than the mea-
sured rate for Lagoon 1. For Lagoon 2,
the predicted rate was orders of magni-
tude greater than the measured rate in
all cases. This discrepancy is attributed
to problems in modeling the sludge/oil/
aqueous surface encountered for this
lagoon. Predicted emissions were
compared to emission rates for Hold-
ing Pond 6 measured using both
concentration-profile and flux chamber
techniques. In general, the predicted
rates are statistically greater than those
measured by the concentration-profile
technique and less than those mea-
sured by the flux chamber.
The Thibodeaux, Parker, and Heck air
emission model was also used to pre-
dict emissions from the spray evapora-
tion pond at Site 6 due to vaporization
of the liquid surface. The model does
not include emissions due to vaporiza-
tion from the spray nozzles and would
therefore be expected to predict lower
emission rates than would be mea-
sured. This was not the case, however.
Due to the poor quality of the transect
data, the measured data are perceived
to have underestimated the true emis-
sion rate. However, it should be noted
that both the predicted and measured
emission rates had very broad confi-
dence intervals, which both included
the corresponding mean values and a
zero emission rate. The imprecision of
the predicted values is attributed to the
wide variability in the concentrations of
compounds found in the pond samples.
The Thibodeaux-Hwang air emission
model was used to predict emissions
from the landfarm. The predicted emis-
sions show a time dependence, with the
emission rate decreasing exponentially.
The effect of retilling the area is to in-
crease emissions initially; however, the
emission rate quickly returns to the
range of values predicted if no tilling
had occurred. The predicted emission
rates were compared with the emission
rates measured using the flux chamber
and concentration-profile techniques. In
general, the predicted emissions agreed
with the measured emissions for spe-
cific compounds, but did not agree with
the compound classes and total non-
methane hydrocarbon emission rates.
In all cases, the predicted emission rates
were significantly greater than the mea-
sured emission rates for the compound
classes and total nonmethane hydrocar-
bons. This discrepancy may be caused,
at least in part, by the composite param-
eters which were used for the com-
pound classes. The Thibodeaux-Hwang
model was developed for single compo-
nents. To apply the model to multicom-
ponent compound groups or classes, a
set of parameters was developed for
each group by averaging the parameter
values of the more prominent com-
pounds contained within the group. A
more sophisticated approach may be
needed to extend the model to multi-
component systems.
Existing predictive models were not
used to estimate emissions from the in-
active chemical landfills in light of the
heterogeneous nature of the waste and
inability of the existing models to ac-
count for vented emissions.
The API imperical model for breath-
ing losses was used to predict breathing
losses from four of the fixed-roof tanks
at Site 6. The annual emission rates pre-
dicted by the API model were then used
to calculate flow rates through the
vents. Additionally, vent flow rates were
calculated based upon vapor displace-
ment calculations. The flow rates calcu-
lated by each method are quite similar,
and all were at or below the detection
limits for the flow measurement tech-
niques used on site. The field observa-
tions and predicted emission rates from
the fixed-roof tanks are therefore con-
sistent with each other.
In summary, the Thibodeaux, Parker,
and Heck surface impoundment model
appears to be generally applicable to in-
dividual compounds in impoundments
having no oil on the surface and/or no
mechanical sprays. The Thibodeaux-
Hwang landtreatment mode! appears to
adequately describe the emissions of
single compounds. However, it was not
found to be satisfactory for compound
classes or total NMHC emissions.
W. D. Balfour, R. G. Wetherold, and D. L Lewis are with Radian Corporation,
Austin, TX 78766.
Paul dePercin is the EPA Project Officer (see below).
The complete report, entitled "Evaluation of A ir Emissions from Hazardous Waste
Treatment, Storage, and Disposal Facilities," (Order No. PB 85-203 792/AS;
Cost: $11.50, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Hazardous Waste Engineering Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
U. S. GOVERNMENT PRINTING OFFICE: 1985/559-111/20624
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Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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