New Installations or Sources. The owner or operator of a new installation or source shall quantify emissions of each TAP that will be discharged and submit that information to the Department when applying for the permit to construct the new installation or source, or when an update is requested by the Department. Emissions shall be quantified in sufficient detail to determine whether the premises complies with the requirements of this chapter. Existing Installations or Sources. The owner or operator of an existing installation or source that, on or before March 1, 1993, either has obtained or was required to obtain a State permit to operate shall quantify emissions of each toxic air pollutant that is discharged that is listed in COMAR 26.11.16.06 and .07B. Emissions shall be quantified in sufficient detail to determine whether the premises complies with the requirements of this chapter. An owner or operator of an existing installation or source shall submit emissions data not later than 1 year after becoming subject to this chapter or not later than the following dates, whichever is later: January 1, 1989, for Class I toxic air pollutants listed in COMAR 26.11.16.06; January 1, 1989, for Class II toxic air pollutants listed in COMAR 26.11.16.07B with a compliance date of July 1, 1990; and January 1, 1991, for any other Class II toxic air pollutants listed in COMAR 26.11.16.07B. Certain Exempt Sources. Certain Premises Discharging Small Quantities of TAP. The owner or operator of a premises exempted from certain requirements under Regulation .03B(3)(a) or (b) of this chapter shall quantify emissions as required by §A or B of this regulation in sufficient detail to demonstrate the Department's satisfaction that emissions are less than the applicable emission rates listed in Regulation .03B(3)(a) or (b) of this chapter. Other Sources Exempt from Regulations .05 or .06. The owner or operator of a NESHAP source or other installation, source, or premises exempted from certain requirements under Regulation .02B, .03B(3)(c), or .03B(4) of this chapter shall quantity emissions as required by §A or B of this regulation. Level of Detail. An initial screening analysis under COMAR 26.11.16.02A may be based on a conservative estimate of emissions that represents good engineering judgment, if the Department determines that the analysis demonstrates applicable screening levels will not be exceeded. If compliance with Regulation .06 of this chapter cannot be demonstrated on this basis, more precise emission estimates shall be used. An owner or operator of a source that discharges more than one toxic air pollutant may demonstrate compliance with Regulation .06 of this chapter by: Quantifying emissions and performing modeling for each TAP individually; Using procedures approved by the Department to quantify TAP emissions and perform modeling for a group of TAPs, and to evaluate concentrations on the basis of the toxicity of the most toxic component or components of the group; or Using other procedures approved by the Department. If several related substances are listed as Class I TAPs or are members of a group of substances listed as a Class I TAP, and these substances are evaluated using a common upper bound unit risk factor, then the substances shall be considered together as one TAP. For example, all hexavalent compounds of chromium that have been determined to be carcinogens shall be considered together as one TAP. Also, dioxin and furan emissions shall be considered together as one TAP and expressed as an equivalent emission of 2,3,7,8-tetrachlorodibenzo-p-dioxin based upon the relative potency of the isomers.