Sunday 14 February 2016

Toxicity Characteristic Leaching Procedure (TCLP)


SECTION A - BOTTLE EXTRACTION PROCEDURE


1. SCOPE AND APPLICATION

    The TCLP is designed to determine the mobility of both organic and inorganic analytes
    present in liquid, solid and multiphasic wastes. The bottle extraction method applies only
    to non-volatile analytes.


2. APPARATUS AND MATERIALS

2.1 Agitation Apparatus

      2.1.1 Tumbler to meet specifications listed in USEPA 1311.



2.2 Extraction Vessels

      2.2.1 2 litre glass TCLP bottles

      2.2.2 Teflon lined lids
      2.2.3 White plumbers tape.

2.3 Filtration Devices

      2.3.1 Millipore Vacuum filtration apparatus

2.4 Filters

      2.4.1 0.6 - 0.8 µm TCLP glass fibre filter paper (142 mm)

2.5 pH Meter

      2.5.1 The meter should be accurate to ± 0.05 units at 25 oC

2.6 Analytical Balance

      2.6.1 Any balance accurate to within ± 0.01 g may be used (all weight measurements are to
               be within ± 0.1 g).

2.7 Beaker or similar container

      2.7.1 Glass or plastic, 100 mL

2.8 Watchglass (suitable size to cover beaker or similar container)

2.9 Magnetic Stirrer


3. REAGENTS

3.1 Hydrochloric acid (HCl), 32 %, AR

3.2 Hydrochloric acid, 1 M: Add 100 mL of 32 % HCl (3.1) to 800 mL of DI water, mix well, then
      bulk up to 1 L.

3.3 Deionised (DI) Water

3.4 Glacial Acetic Acid, AR. Use in a fume cupboard. Where this is not possible keep sealed as
      much as possible when using on the bench.

3.5 Sodium Hydroxide (NaOH), AR

3.6 Nitric Acid, AR

3.7 Extraction Fluid #1: Prepare by mixing 4 L (using a measuring cylinder) of DI water, 22.8 mL
      (using burette) glacial acetic acid (3.4) and 10.25 - 10.30 g of NaOH (3.5). If required, this
      solution must be adjusted to a pH of 4.88 - 4.98 using either NaOH (3.5) or acetic acid (3.4).
      Record this pH.

3.8 Extraction Fluid #2: Prepare by mixing 4 L (using a measuring cylinder) of DI water with 22.8
      mL (using burette) of glacial acetic acid (3.4). The pH of the solution must be 2.83 - 2.93.
      Adjust pH if necessary with NaOH (3.5) or acetic acid (3.4). Record this pH.


4. PRELIMINARY EVALUATIONS

4.1 Determination of Percent Solid

      The percent solid is defined as that fraction of a waste sample from which no liquid may be
      forced out.

      4.1.1 If the waste will obviously yield no liquid when subjected to pressure (that is: it is
               100 % solid) proceed to section 4.2.

      4.1.2 Record the following information in the Miscellaneous Workbook. If the sample is
               liquid or liquid/solid a percent solid determination is required. This is achieved using
               a vacuum filtration device. The first step is to preweigh the filter paper and the
               container which will receive the filtrate. A subsample of the waste is then weighed
               out (a minimum of 100 g) and the weight recorded. This subsample is then
               quantitatively transferred to the filtration device and vacuum applied gradually.
               When continued vacuum does not result in any additional filtrate within any 2 minute
               period, stop the filtration.


      4.1.3 Record the weight of the liquid and solid phases. Calculate the percent solids as
               follows:

                                             weight of solid
               Percent solids = ----------------------------- x 100 %
                                             total weight of waste

               Retain both liquid and solid obtained from this determination.

      4.1.4 If the percent solids is equal to or greater than 0.5 %, the liquid if any, is separated
               from the solid phase and stored for later analysis (see 7.4.). Proceed to section 4.2
               for the solid phase. If the percent of solids is less than 0.5 %, the liquid phase, after
               filtration through a 0.6 - 0.8 µm glass fibre filter, is defined as the TCLP extract.

4.2 Determination of Particle Size Reduction

      Particle size reduction is required unless the solid is smaller than 1 cm in its narrowest
      dimension. If the particle size is larger than described above, prepare the solid portion for
      extraction by crushing, cutting or grinding the waste to a suitable particle size.


5. DETERMINATION AND PREPARATION OF APPROPRIATE EXTRACTION FLUID

5.1 Transfer 5.0 g of the solid phase (after particle size reduction, if required) to a beaker. Add
      96.5 mL of DI water and record the pH of the solution whilst stirring vigorously. If the pH is
      < 5 use extraction fluid #1. If the pH is > 5, proceed to section 5.2.

5.2 Add 3.5 mL, using a 10 mL graduated dispensing pipette, of 1 M HCl to the solution, cover       with a watchglass and heat at 50 oC ± 5ºC (on a water bath) for 10 minutes. Allow to cool
      and record the pH again. If the pH is < 5 use extraction fluid #1. If the pH is > 5 use
      extraction fluid #2.

      Note: Discard this solution - do not use in extraction procedure.


6. EXTRACTION PROCEDURE

6.1 Procedure with regard to percentage of solid

      6.1.1 If the waste is 100 % solid: Weigh out 100 g of prepared waste. Transfer quantitatively
               to a glass TCLP bottle (2 litre capacity) and fill bottle with 2 L (using a measuring
               cylinder) of the appropriate extraction fluid. If less than 100 grams of sample is
               available, then the amount of soil that is available is used, and the volume of
               extraction fluid used is scaled down accordingly. e.g.: if 80 grams of soil is used, then
               1.6 L of extraction fluid is used. This information is recorded in the TCLP workbook.


      6.1.2 If the waste has a mixture of solid and liquid but has more than 0.5 % solid, take the
               filtered and prepared sample (from 4.1 and 4.2) and the filter used to separate the
               liquid from the solid phase (from 4.1), and place into a TCLP bottle.

      Determine the amount of extraction fluid to add to the extraction vessel as follows:

                                                       20 x percent solids (4.1.3) x weight of waste filtered (4.1.2)
Volume of extraction fluid (mL) = -------------------------------------------------------------------
                                                                                          100

      Slowly add this amount of extraction fluid to the TCLP bottle.

      NOTE 1: Ensure that the amount of extraction fluid is going to be sufficient to undertake
      the analysis. If not, use more filtered sample.

      NOTE 2: For further explanation and details, see USEPA 1311, Section 7.2.

6.2 Seal bottle using a Teflon-lined lid and white plumbers tape.

6.3 A blank (containing only extraction fluid) must be run with each batch.

6.4 Waste is extracted by tumbling at 30 ± 2 rpm, for 18 ± 2 hours on the tumbler, at 19 - 25 OC.
      The temperature of the room must be monitored, using a max. - min. thermometer. If the
      temperature falls outside this range then a comment should be made when reporting the
      results.


7. FINAL FILTRATION PROCEDURE

7.1 After tumbling, the waste should be allowed to settle (while standing upright) for at least
      2 hours.

7.2 The supernatant is poured onto the TCLP filter and gravity filtered until no additional liquid
      passes through the filter in any 2 minute interval. A gentle pressure of 10 psi is then
      applied until air moves through the filter. If this does not occur, and no additional liquid
      passes through the filter in any 2 minute interval, the pressure is increased in 10-psi
      increments. This continues until air flows through the filter, or liquid ceases to flow (in a
      2 minute period) at 50 psi.
      Note: Instantaneous application of high pressure can degrade the glass filter and may cause
      premature plugging.


7.3 If the waste contained no initial liquid phase, the filtered liquid material obtained from 7.2
      is defined as the TCLP extract.

7.4 If compatible (multiphases will not result on combination), combine the filtered liquid       resulting from section 7.2 with the initial liquid phase of the waste obtained in section       4.1.2. This combined liquid is defined as the TCLP extract.

7.5 If the initial liquid phase of the waste obtained from section 4.1.2 is not or may not be       compatible with the filtered liquid resulting from section 7.2, do not combine these
      liquids. Analyse the liquids, collectively defined as the TCLP extract, and combine
      the results mathematically. For further explanation see USEPA 1311, section 7.2.14.

7.6 The filtrate is collected in an amber solvent washed glass bottle if organic analysis is       required, a nitric preserved plastic bottle if metals are required, or a natural plastic bottle
      for other analytes. The extracts are stored in the cold room for further analysis.

7.7 The TCLP filter must be washed and the filter paper changed between each sample. If       metals are being analysed for, the filters and filter paper must be rinsed with 10 % nitric
      acid before use.

7.8 The pH of the final extract is recorded.




SECTION B - ZERO - HEADSPACE EXTRACTION PROCEDURE


1. SCOPE AND APPLICATION

    This method applies only to waste being tested for volatile analytes. This procedure is
    applicable to the extraction of WAD and total cyanide and those volatile organic compounds
    listed in Table 1 of USEPA 1311.

    The Zero-Headspace Vessel (ZHE) allows for the initial liquid / solid separation, extraction,
    and final filtration to occur without opening of the vessel.


2. APPARATUS AND MATERIALS

2.1 Zero-Headspace Extraction Vessel (ZHE).

      2.1.1 To meet specifications listed in USEPA 1311.

2.2 ZHE Extract Collection Devices: TEDLAR bags or glass, stainless steel or PTFE gas tight       syringes.

2.3 ZHE Extraction Fluid Transfer Devices; Any device capable of transferring the extraction       fluid into the ZHE without changing the nature of the extraction fluid is acceptable.
      e.g. a positive displacement or peristaltic pump, a gas tight syringe, pressure filtration
      unit, or other ZHE device.

2.4 Filters

      2.4.1 0.6 - 0.8 µm TCLP glass fibre filter paper (142 mm)

2.5 pH Meter
      2.5.1 The meter should be accurate to + 0.05 units at 25 oC

2.6 Analytical Balance

      2.6.1 Any balance accurate to within + 0.01 g may be used (all weight measurements are to
               be within ± 0.1 g).

2.7 Beaker or similar container

      2.7.1 Glass or plastic, 100 mL

2.8 Watchglass (suitable size to cover beaker or similar container)

2.9 Magnetic Stirrer



3. REAGENTS

3.1 Ultra High Purity (UHP) Water

3.2 Glacial Acetic Acid, AR. Use in a fume cupboard. Where this is not possible keep sealed       as much as possible when using on the bench.

3.3 Sodium Hydroxide (NaOH), AR

3.4 Extraction Fluid #1: Prepare by mixing 4 L (using a measuring cylinder) of DI water, 22.8 mL
      (using burette) glacial acetic acid and 10.25 - 10.30 g of NaOH. If required, this solution
      must be adjusted to a pH of 4.88 - 4.98 using either NaOH or acetic acid. Record this pH.


4. PRELIMINARY EVALUATIONS

4.1 Determination of Percent Solid

      TAKE ANY SUBSAMPLES FOR TOTAL SOLIDS DETERMINATION RAPIDLY FROM A COLD SAMPLE
      TO AVOID THE LOSS OF VOLATILES.

      THE SAMPLE USED FOR THE SOLIDS DETERMINATION IS NOT TO BE USED FOR ZHE ANALYSIS.

      The percent solid is defined as that fraction of a waste sample from which no liquid may be
      forced out.

      4.1.1 If the waste will obviously yield no liquid when subjected to pressure (that is: it is
               100 % solid) proceed to section 4.2.

      4.1.2 Record the following information in the Miscellaneous Workbook. If the sample is
               liquid or liquid/solid a percent solid determination is required. This is achieved using
               a vacuum filtration device. The first step is to preweigh the filter paper and the
               container which will receive the filtrate. A subsample of the waste is then weighed
               out (a minimum of 100 g) and the weight recorded. This subsample is then
               quantitatively transferred to the filtration device and vacuum applied gradually.
               When continued vacuum does not result in any additional filtrate within any 2 minute
               period, stop the filtration.

      4.1.3 Record the weight of the liquid and solid phases. Calculate the percent solids
               as follows:

                                             weight of solid
               Percent solids = ----------------------------- x 100 %
                                             total weight of waste


4.2 Determination of Particle Size Reduction

      Particle size reduction is required unless the solid is smaller than 1 cm in its narrowest
      dimension. If the particle size is larger than described above, prepare the solid portion for
      extraction by crushing, cutting or grinding the waste to a suitable particle size.

      IF PARTICLE SIZE REDUCTION IS REQUIRED, THIS IS TO BE CARRIED OUT ON THE SAMPLE
      IMMEDIATELY PRIOR TO EXTRACTION.


5. EXTRACTION PROCEDURE

5.1 Pre-weigh the evacuated filtrate collection container and set aside.

5.2 Place the ZHE piston within the body of the ZHE. Adjust the piston within the ZHE body to
      a height that will minimise the distance the piston will have to move once the ZHE is
      charged with sample. Secure the gas inlet / outlet flange (bottom flange) onto the ZHE
      body in accordance with the manufacturer’s instructions. Secure the glass fibre filter
      between the support screens and set aside. Set the liquid inlet / outlet flange (top flange)
      aside.

5.3 If the waste is 100 % solid, weigh out 25 g of the waste.

5.4 If the percent of solids is less than 0.5 %, the liquid phase, after filtration, is defined as
      the TCLP extract. Filter enough sample so that that the amount of filtrate will support all
      the volatile analysis required. For wastes containing ≥ 0.5 % dry solids (ref 4.1.3), use the
      % solids information to determine the optimum sample size to charge into the ZHE.

5.5 For wastes containing < 5 % solids, weigh out a 500 g subsample and record the weight. 5.6 For wastes containing ≥ 0.5 % solids, determine the amount of waste to charge into the ZHE       as follows:                                                                      25       Weight of waste to charge to ZHE = --------------- x 100                                                              percent solids 5.7 Weigh out a subsample (cold) of the waste of the appropriate size and record the weight. 5.8 Carry out any particle size reduction. 5.9 Transfer quantitatively, as quickly as possible the entire sample to the ZHE. Secure the        filter and support screens onto the top flange of the device and secure the top flange to        the ZHE body in accordance with the manufacturers instructions. Tighten all ZHE fittings        and place the device in the vertical position (gas inlet / outlet flange on the bottom).        Do not attach the extraction collection device to the top plate.        NOTE: If > 1 % of waste material has adhered to the container used to transfer the sample,
       determine the weight of the residue and subtract it from the initial weight.

5.10 Attach a gas line to the gas inlet / outlet valve (bottom flange) and with the liquid inlet        / outlet valve (top flange) open, begin applying gentle pressure of 1 -10 psi (or more if
       necessary) to force all the headspace slowly out of the ZHE device. At the first appearance
       of liquid from the liquid inlet / outlet valve, quickly close the valve and discontinue
       pressure. If filtration of the waste at 4 OC reduces the amount of expressed liquid over
       what would be expressed at room temperature, then allow the sample to warm to room
       temperature in the device before filtering.
       If the waste is 100 % solid, slowly increase the pressure to a maximum of 50 psi to force
       most of the headspace out of the devise. Proceed to 5.15.

5.11 Attach the evacuated pre-weighed filtrate collection container to the liquid inlet / outlet        valve and open the valve. Begin applying gentle pressure of 1 - 10 psi to force the liquid
       phase of the sample into the filtrate collection container. If no additional liquid has
       passed through the filter in any 2 minute interval, slowly increase the pressure in 10-psi
       increments to a maximum of 50 psi. After each incremental increase of 10 psi, if no
       additional liquid has passed through the filter in any 2 minute interval, proceed to the
       next 10-psi increment. When liquid flow has ceased such that continued pressure filtration
       at 50 psi does not result in any additional filtrate within a 2 minute period stop the
       filtration. Close the liquid inlet / outlet valve, discontinue pressure to the piston, and
       disconnect and weigh the filtrate collection container.

       Note: Instantaneous application of high pressure can degrade the glass filter and may
       cause premature plugging.

5.12 The material in the ZHE is defined as the solid phase of the waste and the filtrate is        defined as the liquid phase.

       Note: Some wastes, such as oily wastes and some paint wastes, will obviously contain
       some material that appears to be a liquid. Even after applying pressure filtration, this
       material will not filter. In this case, the material within the filtration device is defined as
       a solid and is carried through the TCLP extraction as a solid.

5.13 If the original waste contained < 0.5 % dry solids, this filtrate is defined as the TCLP        extract and is analysed directly.

5.14 The liquid phase may now be either analysed immediately or stored at 4 OC under minimal        headspace conditions until time of analysis. Determine the weight of solid to add to the
       ZHE as follows:
                                                               100 x 500 mL (Volume of extraction fluid)
       weight of waste filtered (4.1.2) = -----------------------------------------------------
                                                                             20 x percent solids (4.1.3)


5.15 With the ZHE in the vertical position, attach a line from the extraction fluid reservoir to        the liquid inlet / outlet valve. The line used shall contain fresh extractant fluid and should
       be preflushed with fluid to eliminate any air pockets in the line. Release the gas pressure
       on the ZHE piston (from the gas inlet /outlet valve), open the liquid inlet / outlet valve,
       and begin transferring extraction fluid (by pumping or similar means) into the ZHE.
       Continue pumping extraction fluid into the ZHE until the appropriate amount of fluid has
       been introduced into the device.

5.16 After the extraction fluid has been added, immediately close the liquid inlet / outlet
       valve and disconnect the extraction fluid line. Check the ZHE to ensure that all the valves
       are in their closed positions. Manually rotate the device in an end over end fashion 2 or
       3 times. Reposition the ZHE in the vertical position with the liquid inlet / outlet valve on
       top. Pressurise the ZHE to 5-10 psi (if necessary) and slowly open the liquid inlet / outlet
       valve to bleed out any headspace that may have been introduced due to the addition of
       extraction fluid. This bleeding shall be done quickly and shall be stopped at the first
       appearance of liquid from the valve. Re-pressurise the ZHE with 5 -10 psi and check all ZHE
       fittings to ensure that they are closed.

5.17 Place the ZHE in the rotary agitation apparatus (if it is not already there) and rotate at        30 ± 2 rpm for 18 ± 2 hours at 21 - 25 OC.

5.18 After the 18  2 hour agitation period, check the pressure behind the ZHE piston by
       quickly opening and closing the gas inlet / outlet valve and noting the escape of gas. If the
       pressure has not been maintained (i.e. no gas release observed), the device is leaking.
       Check the ZHE for leaking as specified in Appendix 1 - Sect 4.2.1, and perform the
       extraction again with a new sample of waste. If the pressure within the device has been
       maintained, the material in the extractor vessel is once again separated into its
       component liquid and solid phases. If the waste contained an initial liquid phase, the
       liquid may be filtered directly into the same filtrate collection container holding the
       initial liquid phase of the waste. A separate filtrate collection container must be used if
       combining would create multiple phases, or there is not enough volume left within
       the filtrate
       collection container. Filter through the glass fibre filter, using the ZHE device as discussed
       in Sect 5.15. All extract shall be filtered and collected if the extract is multiphasic,
       or if the waste contained an initial liquid phase.

       NOTE: An in-line glass fibre filter may be used to filter the material within the ZHE if it is
       suspected that the glass fibre filter has been ruptured.

5.19 If the waste contained no initial liquid phase, the filtered liquid material obtained from        5.18 is defined as the TCLP extract.

5.20 If compatible (multiphases will not result on combination), combine the filtered liquid        resulting from section 5.18 with the initial liquid phase of the waste obtained in section
       5.12. This combined liquid is defined as the TCLP extract.

5.21 If the initial liquid phase of the waste obtained from section 5.12 is not or may not be        compatible with the filtered liquid resulting from section 5.18, do not combine these
       liquids. Analyse the liquids, collectively defined as the TCLP extract, and combine the
       results mathematically. For further explanation see Appendix 1, section 7.2.14.

5.22 Following the collection of the TCLP extract, the sample is prepared for analysis. Store        extract with minimal headspace at 4 OC.


6. REFERENCE

USEPA Method 1311

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