United States
Environmental Protection
Agency
Hazardous Waste Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-87/043 July 1987
Project Summary
Composition of Leachates from
Actual Hazardous Waste Sites
J. Bramlett, C Furman, A. Johnson, William D. Ellis, H. Nelson,
and William H. Vick
Leachate from 13 hazardous waste
sites In different parts of the country
was analyzed for organic and
inorganic chemical content to
determine patterns and to assess the
feasibility of formulating synthetic
mixtures representative of actual
leachates. Leachates were
approximately 99% aqueous and 1%
organic. Less than 5% of the total
organic content (TOC) was
accounted for in nearly all sites;
consequently recommendations for
synthetic mixtures were based on a
number of assumptions and
compromises. Organic acids and
oxygenated/heteroatomic
hydrocarbons comprised the bulk of
the characterized TOC with
halogenated hydrocarbons present in
lesser but still significant quantities.
This Project Summary was
developed by EPA's Hazardous Waste
Engineering Research Laboratory,
Cincinnati, OH, to announce key
findings of the research project that
is fully documented in a separate
report of the same title (see Project
Report ordering information at back).
Introduction
The Hazardous Waste Engineering
Research Laboratory (HWERL) of the
U.S. Environmental Protection Agency
(USEPA), is interested in determining the
feasibility of formulating a synthetic
hazardous waste leachate, representative
of actual leachates for the purpose of
testing containment liners that are
currently available for use in landfills
treatment, and disposal facilities. To this
end, the USEPA has undertaken a study
to gather data on the composition of
leachate from representative hazardous
waste sites across the country.
Approach
The general approach to this study is
summarized as follows:
Sfep 1; Site Selection - Thirteen
sites were selected for study based on
geographical location, mix of weather
conditions, presence of leachate
collection system, and relatively good
management.
S/ep 2; Sampling and Analysis - Ten
sites were sampled by the contractor
and three were sampled by site
personnel. Field tests included
temperature, pH, redox potential and
conductivity. Laboratory analysis
included tests for volatile and semivolatile
organics using gas chromatography-
mass spectrometry, heavy metals,
cyanide, chemical oxygen demand
(COD) and total organic carbon (TOC).
Sfep 3; Data Evaluation and
Assessment of Formulating Synthetic
Leachate - Laboratory data were
reviewed and leachate quality evaluated.
Based on these data three synthetic
mixtures have been suggested.
Step 4; Report Preparation - A final
report, complete with titles, charts and
figures showing data gathered and
conclusions drawn was prepared.
Evaluation of Total Organic
Carbon (TOC)
The TOC of leachates was used as an
indicator of the level or organic loading.
Subsequent identification and
quantification of individual constituents of
each leachate led to the calculation and
assignment of a portion of the leachate
TOC to each identified constituent.
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Combined, the calculated TOG of
identified constituents comprised a
fraction of the TOG of the leachate - the
larger the fraction, the higher the
success of the analytical program in
achieving maximum identification.
Results
The leachate samples were analyzed
for 35 volatile, 68 semivolatile and 13
metal priority pollutants. In addition, 102
nonpriority pollutant compounds and
families of compounds were identified.
Specifically, the results are presented in
six classes:
1) organic acids,
2) oxygenated/heteroatomic
hydrocarbons,
3) halogenated hydrocarbons,
4) organic bases,
5) aromatic hydrocarbons,
6) aliphatic hydrocarbons.
Of these six classes, the organic acids
and oxygenated/heteroatomic
hydrocarbons constituted 75% of the
characterized TOC. Halogenated
hydrocarbons and aromatic
hydrocarbons were found in lesser
quantities in all sites.
Within a given class, compounds
having higher water solubility accounted
for the highest mole fraction
percentages.
The leachates were analyzed for 13
heavy metals, 8 of which were found in
all sites in varying concentrations. These
included silver, cadmium, chromium,
copper, nickel, lead, selenium and zinc.
Arsenic in high concentration was found
in 10 sites.
The percentage of analytical TOC
which is accounted for in the identified
organics was less that 10% for 11 of the
13 sites and less than 5% for 6 of the 13
sites. These low percentages reflect
large quantities of nonvolatile compounds
or nonextractable components. Overall,
approximately 96% of the TOC remains
unidentified.
Leachate Formulation
While it is recognized that a synthetic
mixture based on a mere 4% of
characterized components may not be
representative of actual leachates, the
information generated in this study is
sufficiently comprehensive to allow
suggestions of three possible formulas:
one incorporates general classes of
compounds in more fractions found to
exist in actual leachates, and the other
two formulas utilize specific chemicals
focused commonly in more than five
sites and at significant concentrations.
The 96% uncharacterized organic
carbon may be represented by high
molecular weight n-alkane or motor oil
that forms a suspension at the 1% level.
This is based on descriptions of
materials disposed of at the waste sites
as being "petroleum based materials" in
nearly all sites.
Recommendation
The project demonstrated the
complexity and the diversity of leachates.
Characterization of leachate constituents
is a difficult, time consuming and
expensive task that requires a more
concentrated effort than was possible
under this task. More detailed analyses
of fewer samples would perhaps provide
a more realistic picture of leachate
compositions. Emphasis should be
placed on the nonvolatile and
nonextractable components which
comprise the bulk of leachate
composition.
*U.S. GPO: 1987—748-012/67190
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J. Bramlett, C. Furman, A. Johnson. W. Ellis, H. Nelson, and W. Vick are with
JRB Associates (SAIC), McLean, VA 22102..
Charles I. Mas/in/ is the EPA Project Officer (see below).
The complete report entitled "Composition of Leachates from Actual Hazardous
Waste Sites," (Order No. PB 87-19d743IAS; Cost: $18.95, 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
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
Official Business
Penalty for Private Use $300
EPA/600/S2-87/043
US EPA
RESIOH V
60604
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