The following limitations establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a point source subject to the provisions of this subpart after application of the best available technology economically achievable:

(a) For normal operation of spray drying towers as defined above, the following values pertain:

(b) For air quality restricted operation of a spray drying tower, but only when a high rate of wet scrubbing is in operation which produces more waste water than can be recycled to process, the following values pertain:

(c) For fast turnaround operation of a spray tower, the following values pertain: The maximum for any one day when the number of turnarounds exceeds six in any particular thirty consecutive day period shall be the sum of the appropriate value below and that from paragraph (a) or (b) of this section; and the average of daily values for thirty consecutive days shall be the values shown below multiplied by the number of turnarounds in excess of six and prorated to thirty days plus the appropriate value from paragraph (a) or (b) of this section.