15A NCAC 02D .1424
(d) For a large non-EGU requesting an alternative monitoring procedure, one of the following monitoring options shall be used to determine NOx emissions.
(1) For sources with at least five years of historical CEMS operational data, the NOx mass emissions shall be determined using the following formula:
M = K*C*Q*t/2000
where;
M is the NOx mass emissions in tons;
K is the conversion constant equal to 1.194E-7 pounds per standard cubic feet-parts per million volume (lb/scf-ppmv);
C is the average NOx concentration of the unit as demonstrated by previous 40 CFR Part 75 monitoring in parts per million volume (ppmv);
Q is the average flow rate of the unit under normal operating conditions as demonstrated by previous 40 CFR Part 75 monitoring in standard cubic feet per hour (scf/hr);
t is the total operating time in hours during the ozone season; and
2000 pounds per ton (2000 lb/ton).
(2) For sources with at least five years of historical CEMS emissions data, the NOx mass emissions shall be determined as follows:
M = R*HI*t/2000
where;
M is the NOx mass emissions in tons,
R is the average NOx mass emission rate in pounds per million Btu (lb/MMBtu),
HI is the average heat input rate per hour in million British thermal units per hour (MMBtu/hr),
t is the operating time in hours during ozone season, and
2000 pounds per ton (2000 lb/ton).
(3) For sources without historical CEMS operational data or the CEMS data do not represent current operating conditions, the large non-EGU source shall test utilizing 40 CFR Part 60, Appendix A, Methods 1-4 and 7 or 7e to determine initial NOx concentration and flow rate factors prior to the ozone season.
History Note: Authority G.S. 143-215.3(a)(1); 143-215.65; 143-215.66; 143.215.107(a)(5); 143.215.107(a)(7); 143.215.107(a)(10);
Eff. May 1, 2022.