Section 326IAC3-7-3. Alternative coal sampling and analysis methods

   (a) As an alternative to the coal sampling and analysis procedures in section 2 of this rule, a source owner or operator may use manual or other non-ASTM automatic sampling and analysis procedures upon a demonstration as described in subsection (b), submitted to and approved by the department and U.S. EPA that the procedures provide sulfur dioxide emission estimates representative either of estimates based on coal sampling and analysis procedures specified in section 2 of this rule or of continuous emissions monitoring.

  (b) For the demonstration described in this section, a source owner or operator may submit documentation of procedures and results of a stopped-belt bias test or other comparisons between a sampling system meeting the requirements of section 2 of this rule and those methods and procedures proposed by the source owner or operator. A stopped-belt bias test and a sampling system meeting the requirements of section 2 of this rule shall be considered reference method systems. A comparison shall utilize a series of at least twenty-five (25) reference method system samples paired with nonreference method system samples and analyzed for the percent of sulfur content to determine the presence of significant systemic error. The detection of significant systemic error shall be based on the application of a statistical test (t-test) to determine if there is a difference between the reference and nonreference systems at the ninety-five percent (95%) confidence level, according to the following formula:

Where:	t	=	Calculated t value.
	d	=	Average difference between paired data.
	Sd	=	Standard deviation of the differences.
	N	=	Number of paired data sets.

The calculated t value is compared to the t value in the standard statistical t tables at the ninety-five percent (95%) probability and the appropriate degrees of freedom (n - 1). If the calculated t value is greater than or equal to the value of t in the t table, then the systems are not comparable. Certain coals with low variability may detect a small bias, which may be acceptable as decided on a case-by-case basis. This method tests for positive and negative bias. Provisions for testing only for a negative bias that would cause a source owner or operator to report less than actual values may be acceptable if supported by statistical tests. Upon request, the department shall provide written guidance to a source owner or operator as to the procedures to be followed in conducting this comparison.

  (c) The demonstration described in this section shall be repeated upon any significant change to the coal sampling procedures or upon notification by the department that a new demonstration is necessary. If the department has reason to doubt that the alternative sampling and analysis procedures are comparable to methods and procedures provided in section 2 of this rule, based on:

(1) inspections;

(2) monitoring;

(3) quality assurance data; or

(4) other information;

the department may notify the owner or operator that the demonstration shall be repeated. Written notification by the department of the request shall be made to the source owner or operator allowing at least sixty (60) days to schedule the demonstration. (Air Pollution Control Division; 326 IAC 3-7-3; filed Jan 30, 1998, 4:00 p.m.: 21 IR 2077; readopted filed Jan 10, 2001, 3:20 p.m.: 24 IR 1477; filed Aug 11, 2011, 1:54 p.m.: 20110907-IR-326050330FRA)