Sampling
(i) Sampling. Wastewater samples may be grab samples or composite samples. Samples shall be taken at approximately equally spaced time intervals over a 1-hour period (or over the period that wastewater is being discharged from a batch process if it is shorter than a 1-hour period). Each 1-hour period constitutes a run, and a performance test shall consist of a minimum of 3 runs. (ii) Methods. You may use any of the methods specified in paragraphs (c)(1)(ii)(A) through (E) of this section to determine the organic HAP content of the wastewater stream. The method shall be an analytical method for wastewater which has the organic HAP compound discharged to the wastewater as a target analyte. (A) Method 305. Use procedures specified in Method 305 of 40 CFR part 63, appendix A. (B) Methods 624 and 625. Use procedures specified in Method 624 and Method 625 of 40 CFR part 136, appendix A and comply with the sampling protocol requirements specified in paragraph (c)(1)(iii) of this section. If these methods are used to analyze one or more compounds that are not on the method's published list of approved compounds, the Alternative Test Procedure specified in 40 CFR 136.4 and 136.5 shall be followed. For Method 625, make corrections to the compounds for which the analysis is being conducted based on the accuracy as recovery factors in Table 7 of the method. (C) Methods 1624 and 1625. Use procedures specified in Method 1624 and Method 1625 of 40 CFR part 136, appendix A and comply with the sampling protocol requirements specified in paragraph (c)(1)(iii) of this section. If these methods are used to analyze one or more compounds that are not on the method's published list of approved compounds, the Alternative Test Procedure specified in 40 CFR 136.4 and 136.5 shall be followed. (D) Other EPA method(s). Use procedures specified in the method and comply with the requirements specified in paragraphs (c)(1)(iii) and either paragraph (c)(1)(iv)(A) or (B) of this section. (E) Methods other than EPA method. Use procedures specified in the method and comply with the requirements specified in paragraphs (c)(1)(iii) and paragraph (c)(1)(iv)(A) of this section. (iii) Sampling plan. If you have been expressly referred to this paragraph by provisions of this subpart, you shall prepare a sampling plan. Wastewater samples shall be collected using sampling procedures which minimize loss of organic compounds during sample collection and analysis and maintain sample integrity. The sampling plan shall include procedures for determining recovery efficiency of the relevant organic HAP. An example of an example sampling plan would be one that incorporates similar sampling and sample handling requirements to those of Method 25D of 40 CFR part 60, appendix A. You shall maintain the sampling plan at the facility. (iv) Validation of methods. You shall validate EPA methods other than Methods 305, 624, 625, 1624, 1625 using the procedures specified in paragraph (c)(1)(iv)(A) or (B) of this section. (A) Validation of EPA methods and other methods. The method used to measure organic HAP concentrations in the wastewater shall be validated according to section 5.1 or 5.3, and the corresponding calculations in section 6.1 or 6.3, of Method 301 of appendix A of this part. The data are acceptable if they meet the criteria specified in section 6.1.5 or 6.3.3 of Method 301 of appendix A of this part. If correction is required under section 6.3.3 of Method 301 of appendix A of this part, the data are acceptable if the correction factor is within the range 0.7 to 1.30. Other sections of Method 301 of appendix A of this part are not required. (B) Validation for EPA methods. Follow the procedures as specified in Alternative Validation Procedure for EPA Waste Methods 40 CFR part 63, appendix D. (v) Calculate the average concentration. You shall calculate the average concentration for each individually speciated organic HAP compound by adding the individual values determined for the specific compound in each sample and dividing by the number of samples. (vi) Adjustment for concentrations determined downstream of the point of determination. You shall make corrections to the specific compound average concentration or total organic HAP average concentration when the concentration is determined downstream of the point of determination at a location where either wastewater streams from outside of the affected dyeing/finishing operation or group of dyeing/finishing operations have been mixed with the affected wastewater stream or one or more affected wastewater streams have been treated. You shall make the adjustments either to the individual data points or to the final average organic HAP concentration. (2) Procedures to determine mass flow rate. For each operating scenario, as defined in 63.4371, for which you have determined the organic HAP content of the wastewater stream, you shall determine the annual average mass flow rate, Fw, of the wastewater stream either at the point of determination or downstream of the point of determination with adjustment for flow rate changes made according to paragraph (c)(2)(ii) of this section. The annual average mass flow rate for the wastewater stream shall be representative of actual or anticipated operation of the dyeing/finishing operation(s) generating the wastewater over the compliance period. You must determine the annual average mass flow rate of each wastewater stream according to paragraphs (c)(2)(i) and (ii) of this section. (i) Procedures. The procedures specified in paragraphs (c)(2)(i)(A) through (C) of this section are considered acceptable procedures for determining the mass flow rate. They may be used in combination, and no one procedure shall take precedence over another. (A) Knowledge of the wastewater. You may use knowledge of the wastewater stream and/or the process to determine the annual average mass flow rate. You shall use the maximum expected annual average production capacity of the dyeing/finishing operation(s), knowledge of the process, and/or mass balance information to either estimate directly the average wastewater mass flow rate for the compliance period or estimate the total wastewater mass flow for the compliance period and then factor the total mass by the percentage of time in the compliance period the operating scenario is expected to represent. Where you use knowledge to determine the annual average mass flow rate, you shall provide sufficient information to document the mass flow rate. (B) Historical records. You may use historical records to determine the average annual mass flow rate. Derive the highest annual average mass flow rate of wastewater from historical records representing the most recent 5 years of operation, or if the dyeing/finishing operation(s) has(have) been in service for less than 5 years but at least 1 year, from historical records representing the total operating life of the process unit. Where historical records are used to determine the annual average mass flow rate, you shall provide sufficient information to document the mass flow rate. (C) Measurement of mass flow rate. If you elect to measure mass flow rate, you shall comply with the requirements of this paragraph. Measurements shall be made at the point of determination, or at a location downstream of the point of determination with adjustments for mass flow rate changes made according to paragraph (c)(2)(ii) of this section. Where measurement data are used to determine the annual average mass flow rate, you shall provide sufficient information to document the mass flow rate. (ii) Adjustment for flow rates determined downstream of the point of determination. You shall make corrections to the average annual mass flow rate of a wastewater stream when it is determined downstream of the point of determination at a location where either wastewater streams from outside of the affected dyeing/finishing operation or group of dyeing/finishing operations have been mixed with the affected wastewater stream or one or more wastewater streams have been treated. You shall make corrections for such changes in the annual average mass flow rate. (3) Wastewater treatment. You shall document that the wastewater is either discharged to a POTW or onsite secondary wastewater treatment. (4) Determine the mass of organic HAP in the affected wastewater. Determine the total mass of organic HAP, WW, contained in the wastewater streams characterized by the procedures in paragraphs (c)(1) and (2) of this section, using Equation 7 of this section: