Section 326IAC8-20-9. Determination of wastewater characteristics

   The determination of the characteristics of a wastewater stream for purposes of this rule shall be made as follows:

(1) The characteristics shall be determined at a location between the point of generation (as defined by this rule) and before the wastewater stream is exposed to the atmosphere, treated for VOC removal, or mixed with another wastewater stream.

(2) The flow rate of a wastewater stream shall be determined on the basis of an annual average by one (1) of the following methods:

(A) The highest annual quantity of wastewater managed, based on historical records for the most recent five (5) years of operation, or for the entire time the wastewater stream has existed if less than five (5) years, but at least one (1) year.

(B) The maximum design capacity of the waste management unit.

(C) The maximum design capacity to generate wastewater of the process unit generating the wastewater stream.

(D) Measurements that are representative of the actual, normal wastewater generation rates.

(3) If the department or U.S. EPA determines that the VOC concentration cannot be adequately determined by knowledge of the wastewater, or by bench-scale or pilot-scale test data, the VOC concentration shall be determined in accordance with clause (C), or by a combination of the methods in clauses (A) through (C). VOC with a "Henry's Law Constant" less than 1.8 × 10^-6 atm-m3/mole (0.1 y/x) at twenty-five (25) degrees Celsius shall not be included in the determination of VOC concentration. The VOC concentration of a wastewater stream shall be determined on the basis of a flow-weighted annual average by one (1) or more of the following methods:

(A) Knowledge of the wastewater. Sufficient information to document the VOC concentration. Examples of information include the following:

(i) Material balances.

(ii) Records of chemical purchases.

(iii) Previous test results.

(B) Bench-scale or pilot-scale test data. Sufficient information to demonstrate that the bench-scale or pilot-scale test concentration data are representative of the actual VOC concentration.

(C) Measurements. Collect a minimum of three (3) representative samples from the wastewater stream and determine the affected VOC concentration for each sample in accordance with section 7 of this rule (relating to approved test methods). The affected VOC concentration of the wastewater stream shall be the flow-weighted average of the individual samples.

(4) The annual affected VOC loading in wastewater for a wastewater stream shall be the annual average flow rate determined in subdivision (2) multiplied by the annual average affected VOC concentration determined in subdivision (3).

(5) The annual VOC loading in wastewater for a source shall be the sum of the annual VOC loading in wastewater for each affected VOC wastewater stream.

(6) The "Henry's Law Constant" shall be determined by the procedures in 40 CFR 60, Appendix J*, as proposed on December 9, 1998, in the Federal Register*.

  *These documents are incorporated by reference. Copies may be obtained from the Government Printing Office, 732 North Capitol Street NW, Washington, D.C. 20401 or are available for review and copying at the Indiana Department of Environmental Management, Office of Air Quality, Indiana Government Center North, Tenth Floor, 100 North Senate Avenue, Indianapolis, Indiana 46204. (Air Pollution Control Division; 326 IAC 8-20-9; filed Nov 3, 2009, 3:32 p.m.: 20091202-IR-326090222FRA; errata filed Nov 19, 2009, 10:03 a.m.: 20091216-IR-326090222ACA)