The TCLP,or Toxicity Characteristic Leaching(not Leachate)Procedure is designed to determine the mobility of both organic and inorganic analytes present in liquid,solid, and multiphasic wastes.This is usually used to determine if a waste may meet the definition of EP Toxicity,that is,carrying a hazardous waste code under RCRA(40 CFR Part261)of D004through D052.As it is the generator's responsibility to make this determination,but generators often contract outside labs to perform the TCLP test, these questions and answers may be helpful to generators.For this reason and sometimes in cleanup actions,businesses are often asked to perform an analysis on their waste using the TCLP.The Code of Federal Regulations(CFR)
40CFR§261.24,outlines the40contaminants the TCLP analysis tests for(See Table 1—Maximum Concentration of Contaminants for Toxicity Characteristic).I f a“S o l i d Wa s t e”f a i l s t h e t e s t f o r one or more of these compounds,the waste is considered to be a characteristic hazardous waste–unless there is an exemption that applies.Bear in mind,too,that a characteristic waste may still also be a“l i s t e d”h a z a r d o u s w a s t e. The procedure follows below.For more general information,FAQs and guidances, see www.ehso/
1.0SCOPE AND APPLICATION
1.1The TCLP is designed to determine the mobility of both organic
and inorganic analytes present in liquid,solid,and
multiphasic wastes.
1.2If a total analysis of the waste demonstrates that individual
analytes are not present in the waste,or that they are present
but at such low concentrations that the appropriate regulatory
levels could not possibly be exceeded,the TCLP need not be
run.
1.3If an analysis of any one of the liquid fractions of the TCLP
extract indicates that a regulated compound is present at such
high concentrations that,even after accounting for dilution
from the other fractions of the extract,the concentration would
be above the regulatory level for that compound,then the waste
is hazardous and it is not necessary to analyze the remaining
fractions of the extract.
1.4If an analysis of extract obtained using a bottle extractor
shows that the concentration of any regulated volatile analyte
exceeds the regulatory level for that compound,then the waste
is hazardous and extraction using the ZHE is not necessary.
However,extract from a bottle extractor cannot be used to
demonstrate that the concentration of volatile compounds is
below the regulatory level.
2.0SUMMARY OF METHOD
2.1For liquid ,those containing less than0.5%dry
solid material),after filtration through a0.6to Page1of38TCLP;Method1311-1Revision0July1992
0.8µm glass fiber filter,is defined as the TCLP extract.
2.2For wastes containing greater than or equal to0.5%solids,the
liquid,if any,is separated from the solid phase and stored for
later analysis;the particle size of the solid phase is reduced,
if necessary.The solid phase is extracted with an amount of
extraction fluid equal to20times the weight of the solid phase.
The extraction fluid employed is a function of the alkalinity of
the solid phase of the waste.A special extractor vessel is used
when testing for volatile analytes(see Table1for a list of
volatile compounds).Following extraction,the liquid extract is
separated from the solid phase by filtration through a0.6to0.8
µm glass fiber filter.
2.3If ,multiple phases will not form on
combination),the liquid phase of the waste is added to
the liquid extract,and these are analyzed together.If
incompatible,the liquids are analyzed separately and the results
are mathematically combined to yield a volume-weighted average
concentration.
3.0INTERFERENCES
3.1Potential interferences that may be encountered during analysis
are discussed in the individual analytical methods.
4.0APPARATUS AND MATERIALS
4.1Agitation apparatus:The agitation apparatus must be capable of
rotating the extraction vessel in an end-over-end fashion(see
Figure1)at30+2rpm.Suitable devices known to EPA are
identified in Table 2.
4.2Extraction Vessels
4.2.1Zero-Headspace Extraction Vessel(ZHE).This device is
for use only when the waste is being tested for the
mobility of volatile ,those listed in
Table1).The ZHE(depicted in Figure2)allows for
liquid/solid separation within the device,and
effectively precludes headspace.This type of vessel
allows for initial liquid/solid separation,extraction,
and final extract filtration without opening the vessel
(see Section 4.3.1).The vessels shall have an internal
volume of500-600mL,and be equipped to accommodate a90-
110mm filter.The devices contain VITON O-rings which
should be replaced frequently.Suitable ZHE devices
known to EPA are identified in Table 3.
For the ZHE to be acceptable for use,the piston within
the ZHE should be able to be moved with approximately15
psi or less.If it takes more pressure to move the
piston,the O-rings in the device should be replaced.If Page2of38TCLP;Method1311-2Revision0July1992
this does not solve the problem,the ZHE is unacceptable
for TCLP analyses and the manufacturer should be
contacted.
The ZHE should be checked for leaks after every
extraction.If the device contains a built-in pressure
gauge,pressurize the device to50psi,allow it to stand
unattended for1hour,and recheck the pressure.If the
device does not have a built-in pressure gauge,
pressurize the device to50psi,submerge it in water,
and check for the presence of air bubbles escaping from
any of the fittings.If pressure is lost,check all
fittings and inspect and replace O-rings,if necessary.
Retest the device.If leakage problems cannot be solved,
the manufacturer should be contacted.
Some ZHEs use gas pressure to actuate the ZHE piston,
while others use mechanical pressure(see Table3).
Whereas the volatiles procedure(see Section7.3)refers
to pounds per square inch(psi),for the mechanically
actuated piston,the pressure applied is measured in
torque-inch-pounds.Refer to the manufacturer's
instructions as to the proper conversion.1®
VITON is a trademark of Du Pont.CD-ROM1311-2
4.2.2Bottle Extraction Vessel.When the waste is being
evaluated using the nonvolatile extraction,a jar with
sufficient capacity to hold the sample and the extraction
fluid is needed.Headspace is allowed in this vessel.
The extraction bottles may be constructed from various
materials,depending on the analytes to be analyzed and
the nature of the waste(see Section 4.3.3).It is
recommended that borosilicate glass bottles be used
instead of other types of glass,especially when
inorganics are of concern.Plastic bottles,other than
polytetrafluoroethylene,shall not be used if organics
are to be investigated.Bottles are available from a
number of laboratory suppliers.When this type of
extraction vessel is used,the filtration device
discussed in Section 4.3.2is used for initial
liquid/solid separation and final extract filtration.
4.3Filtration Devices:It is recommended that all filtrations be
performed in a hood.
4.3.1Zero-Headspace Extractor Vessel(ZHE):When the waste is
evaluated for volatiles,the zero-headspace extraction
vessel described in Section 4.2.1is used for filtration.
The device shall be capable of supporting and keeping in
place the glass fiber filter and be able to withstand
the pressure needed to accomplish separation(50psi).
NOTE:When it is suspected that the glass fiber filter Page3of38TCLP;Method1311-3Revision0July1992
has been ruptured,an in-line glass fiber filter
may be used to filter the material within the ZHE.
4.3.2Filter Holder:When the waste is evaluated for other
than volatile analytes,any filter holder capable of
supporting a glass fiber filter and able to withstand
the pressure needed to accomplish separation may be
used.Suitable filter holders range from simple vacuum
units to relatively complex systems capable of exerting
pressures of up to50psi or more.The type of filter
holder used depends on the properties of the material to
be filtered(see Section 4.3.3).These devices shall
have a minimum internal volume of300mL and be equipped
to accommodate a minimum filter size of47mm(filter
holders having an internal capacity of 1.5L or greater,
and equipped to accommodate a142mm diameter filter,
are recommended).Vacuum filtration can only be used
for wastes with low solids content(<10%)and for highly
granular,liquid-containing wastes.All other types of
wastes should be filtered using positive pressure
filtration.Suitable filter holders known to EPA are
shown in Table 4.
4.3.3Materials of Construction:Extraction vessels and
filtration devices shall be made of inert materials
which will not leach or absorb waste components.Glass,
polytetrafluoroethylene(PTFE),or type316stainless
steel equipment may be used when evaluating the
mobility of both organic and inorganic components.
Devices made of high density polyethylene(HDPE),
polypropylene(PP),or polyvinyl chloride(PVC)may be
used only when evaluating the mobility of metals.
Borosili-cate glass bottles are recommended for use
over other types of glass bottles,especially when
inorganics are analytes of concern.
4.4Filters:Filters shall be made of borosilicate glass fiber,
shall contain no binder materials,and shall have an
effective pore size of0.6to0.8µm,or equivalent.Filters
known to EPA which meet these specifications are identified in
Table 5.Pre-filters must not be used.When evaluating the
mobility of metals,filters shall be acid-washed prior to use
by rinsing with1N nitric acid followed by three consecutive
rinses with deionized distilled water(a minimum of1L per
rinse is recommended).Glass fiber filters are fragile and
should be handled with care.
4.5pH Meters:The meter should be accurate to+0.05units at25
E C.
®2
4.6ZHE Extract Collection Devices:TEDLAR bags or glass,
stainless steel or PTFE gas-tight syringes are used to collect Page4of38TCLP;Method1311-4Revision0July1992
the initial liquid phase and the final extract of the waste when
using the ZHE device.The devices listed are recommended for
use under the following conditions:
4.6.1If a waste contains an aqueous liquid phase or if a
waste does not contain a significant amount of
nonaqueous ,<1%of total waste),the
TEDLAR bag or a should be used to
collect and combine the initial liquid and solid
extract.
4.6.2If a waste contains a significant amount of
nonaqueous liquid in the initial liquid ,
>1%of total waste),the syringe or the TEDLAR
be used for both the initial solid/liquid separation
and the final extract filtration.However,analysts
editor evaluating revisionshould use one or the other,not both.
4.6.3If the waste contains no initial liquid phase(is
100%solid)or has no significant solid phase(is
100%liquid),either the TEDLAR bag or the syringe
may be used.If the syringe is used,discard the
first5mL of liquid expressed from the device.The
remaining aliquots are used for analysis.
4.7ZHE Extraction Fluid Transfer Devices:Any device capable of
transferring the extraction fluid into the ZHE without changing
the nature of the extraction fluid is ,a
positive displacement or peristaltic pump,a gas tight syringe,
pressure filtration unit(see Section 4.3.2),or other ZHE
device).
4.8Laboratory Balance:Any laboratory balance accurate to within+
0.01grams may be used(all weight measurements are to be within
+0.1grams).
4.9Beaker or Erlenmeyer flask,glass,500mL.2®
TEDLAR is a registered trademark of Du Pont.
4.10Watchglass,appropriate diameter to cover beaker or Erlenmeyer
flask.
4.11Magnetic stirrer.
5Reagents
5.1Reagent grade chemicals shall be used in all tests.Unless
otherwise indicated,it is intended that all reagents shall
conform to the specifications of the Committee on Analytical
Reagents of the American Chemical Society,where such
specifications are available.Other grades may be used,
provided it is first ascertained that the reagent is of Page5of38TCLP;Method1311-5Revision0July1992
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