No person owning or operating any stationary source, not otherwise addressed in this Part, shall cause or allow visible air contaminant emissions that exceed an opacity of 20 percent, 6 minute time-averaged.

[11/28/89. . .11/1/95; 20.11.5.12 NMAC - Rn, 20 NMAC 11.05.I.12 & Repealed; Rn, 20 NMAC 11.05.II.1, 10/1/02]