Q = X(3.28) + Y(1.60) + Z(0.5) / X + Y +Z
where Q is the sulfur dioxide emission limit for a stack expressed in pounds of sulfur dioxide per million Btu heat input, X is the percent of total heat input derived from solid fossil fuel, Y is the percent of total heat input derived from residual fuel oil, and Z is the percent of total heat input derived from all other fuels.
Wis. Admin. Code Department of Natural Resources NR 418.04