collected in the organic phase. Place the organic extract in a tared 350-ml weighing tin. 5.3.2.2 Organic Fraction Weight Determination (Organic Phase from Container Nos. 4 and 5). Evaporate the organic extract at room temperature and pressure in a laboratory hood. Following evaporation, desiccate the organic fraction for 24 hours in a desiccator containing anhydrous calcium sulfate. Weigh to a constant weight and report the results to the nearest 0.1 mg. 5.3.2.3 Inorganic Fraction Weight Determination. (Note: If NH4Cl is to be counted as CPM, the inorganic fraction should be taken to near dryness (less than 1 ml liquid) in the oven and then allow to air dry at ambient temperature. If multiple acid emissions are suspected, the ammonia titration procedure in section 8.1 may be preferred.) Using a hot plate, or equivalent, evaporate the aqueous phase to approximately 50 ml; then, evaporate to dryness in a 105 °C oven. Redissovle the residue in 100 ml of water. Add five drops of phenolphthalein to this solution; then, add concentrated (14.8 M) NH4OH until the sample turns pink. Any excess NH2OH will be evaporated during the drying step. Evaporate the sample to dryness in a 105 °C oven, desiccate the sample for 24 hours, weigh to a constant weight, and record the results to the nearest 0.1 mg. (Note: The addition of NH4OH is recommended, but is optional when little or no SO2 is present in the gas stream, 1.e., when the pH of the impinger solution is greater than 4.5, the addition of NH4OH is not necessary.) 5.3.2.4 Analysis of Sulfate by IC to Determine Ammonium Ion (NH) Retained in the Sample. (Note: If NH4OH is not added, omit this step.) Determine the amount of sulfate in the aliquot taken from Container No. 4 earlier as described in Method 5F (appendix A, 40 CFR part 60). Based on the IC SO1-2 analysis of the aliquot, calculate the correction factor to subtract the NH4+ retained in the sample and to add the combined water removed by the acid-base reaction (see section 7.2). 5.3.3 Analysis of Water and MeCl2 Blanks (Container Nos. 6 and 7). Analyze these sample blanks as described above in sections 5.3.2.3 and 5.3.2.2, respectively. 5.3.4 Analysis of Acetone Blank (Container No. 8). Same as in Method 17, section 4.3. 6. Calibration Same as in Method 17, section 5, except for the following: 6.1 IC Calibration. Same as Method 5F, section 5. 6.2 Audit Procedure. Concurrently, analyze the audit sample and a set of compliance samples in the same manner to evaluate the technique of the analyst and the standards preparation. The same analyst, analytical reagents, and analytical system shall be used both for compliance samples and the EPA audit sample. If this condition is met, auditing of subsequent compliance analyses for the same enforcement agency within 30 days is not required. An audit sample set may not be used to validate different sets of compliance samples under the jurisdiction of different enforcement agencies, unless prior arrangements are made with both enforcement agencies. 6.3 Audit Samples. Audit Sample Availability. Audit samples will be supplied only to enforcement agencies for compliance tests. The availability of audit samples may be obtained by writing: Source Test Audit Coordinator (MD-77B), Quality Assurance Division, Atmospheric Research and Exposure Assessment Laboratory, U.S. Environmental Protection Agency, Research Triangle, Park, NC 27711 or by calling the Source Test Audit Coordinator (STAC) at (919) 541-7834. The request for the audit sample must be made at least 30 days prior to the scheduled compliance sample analysis. 6.4 Audit Results. Calculate the audit sample concentration according to the calculation procedure described in the audit instructions included with the audit sample. Fill in the audit sample concentration and the analyst's name on the audit response form included with the audit instructions. Send one copy to the EPA Regional Office or the appropriate enforcement agency and a second copy to the STAC. The EPA Regional Office or the appropriate enforcement agency will report the results of the audit to the laboratory being audited. Include this response with the results of the compliance samples in relevant reports to the EPA Regional Office or the appropriate enforcement agency. 7. Calculations Same as in Method 17, section 6, with the following additions: 7.1 Nomenclature. Same as in Method 17, section 6.1 with the following additions. Ccpm=Concentration of the CPM in the stack gas, dry basis, corrected to standard conditions, g/dscm (g/dscf). Cso4-Concentration of SO4-2 in the sample, mg/ml. m, Sum of the mass of the water and MeCl2 blanks, mg. m-Mass of the NH4+ added to sample to form ammonium sulfate, mg. m=Mass of inorganic CPM matter, mg. m.-Mass of organic CPM, mg. m, Mass of dried sample from inorganic fraction, mg. V=Volume of aliquot taken for IC analysis, ml. Vic=Volume of impinger contents sample, ml. 7.2 Correction for NH4+ and H2O. Calculate the correction factor to subtract the 8.1 Determination of NH4+ Retained in Sample by Titration. 8.1.1 An alternative procedure to determine the amount of NH4+ added to the inorganic fraction by titration may be used. After dissolving the inorganic residue in 100 ml of water, titrate the solution with 0.1 N NH4OH to a pH of 7.0, as indicated by a pH meter. The 0.1 N NH4OH is made as follows: Add 7 ml of concentrated (14.8 M) NH4OH to 1 liter of water. Standardize against standardized 0.1 N H2SO4 and calculate the exact normality using a procedure parallel to that described in section 5.5 of Method 6 (appendix A, 40 CFR part 60). Alternatively, purchase 0.1 N NH4OH that has been standardized against a National Institute of Standards and Technology reference material. 8.1.2 Calculate the concentration of SO4-2 in the sample using the following equation. drying of the sample should have removed all HCl. Therefore, the remaining chlorides measured by IC can be assumed to be NH.C1, and this weight can be subtracted from the weight determined for CPM. 8.3 Air Purge to Remove SO2 from Impinger Contents. As an alternative to the post-test N2 purge described in section 5.2.1, the tester may opt to conduct the post-test purge with air at 20 liter/min. Note: The use of an air purge is not as effective as a N2 purge. 8.4 Chloroform-ether Extraction. As an alternative to the methylene chloride extraction described in section 5.3.2.1, the tester may opt to conduct a chloroform-ether extraction. Note: The Chloroform-ether was not as effective as the MeCl2 in removing the organics, but it was found to be an acceptable organic extractant. Chloroform and diethylether of ACS grade, with low blank values (0.001 percent), shall be used. Analysis of the chloroform and diethylether blanks shall be conducted according to Section 5.3.3 for MeCl2. 8.4.1 Add the contents of Container No. 4 to a 1000-ml separatory funnel. Then add 75 ml of chloroform to the funnel, mix well, and drain off the lower organic phase. Repeat two more times with 75 ml of chloroform. Then perform three extractions with 75 ml of diethylether. This extraction should yield approximately 450 ml of organic extraction. Each time, leave a small amount of the organic/MeCl2 phase in the separatory funnel ensuring that no water is collected in the organic phase. 8.4.2 Add the contents of Container No. 5 to the organic extraction. Place approximately 300 ml of the organic extract in a tared 350-ml weighing tin while storing the remaining organic extract in a sample container. As the organic extract evaporates, add the remaining extract to the weighing tin. 8.4.3 Determine the weight of the organic phase as described in Section 5.3.2.2. 8.5 Improving Collection Efficiency. If low impinger collection efficiency is suspected, the following procedure may be used. 8.5.1 Place an out-of-stock filter as described in Method 8 between the second and third impingers. 8.5.2 Recover and analyze the filter according to Method 17, Section 4.2. Include the filter holder as part of the connecting glassware and handle as described in sections 5.2.2.2 and 5.2.2.3. 8.5.3 Calculate the Concentration of CPM as follows: where: m = amount of CPM collected on out-ofstack filter, mg. 8.6 Wet Source Testing. When testing at a wet source, use a heated out-of-stack filter as described in Method 5. 9. Bibliography 1. DeWees, W.D., S.C. Steinsberger, G.M. Plummer, L.T. Lay, G.D. McAlister, and R.T. Shigehara. "Laboratory and Field Evaluation of the EPA Method 5 Impinger Catch for Measuring Condensible Matter from Stationary Sources." Paper presented at the 1989 EPA/AWMA International Symposium on Measurement of Toxic and Related Air Pollutants. Raleigh, North Carolina. May 1-5, 1989. 2. DeWees, W.D. and K.C. Steinsberger. "Method Development and Evaluation of Draft Protocol for Measurement of Condensible Particulate Emissions." Draft Report. November 17, 1989. 3. Texas Air Control Board, Laboratory Division. "Determination of Particulate in Stack Gases Containing Sulfuric Acid and/or Sulfur Dioxide." Laboratory Methods for Determination of Air Pollutants. Modified December 3, 1976. 4. Nothstein, Greg. Masters Thesis. University of Washington. Department of Environmental Health. Seattle, Washington. 5. "Particulate Source Test Procedures Adopted by Puget Sound Air Pollution Control Agency Board of Directors." Puget Sound Air Pollution Control Agency, Engineering Division. Seattle, Washington. August 11, 1983. 6. Commonwealth of Pennsylvania, Department of Environmental Resources. Chapter 139, Sampling and Testing (Title 25, Rules and Regulations, Part I, Department of Environmental Resources, Subpart C, Protection of Natural Resources, Article III, Air Resources). January 8, 1960. 7. Wisconsin Department of Natural Resources. Air Management Operations Handbook, Revision 3. January 11, 1988. |