Document Lg7m0dQ0Zg9MyVB49mBn8Y7gw

Huy 6, 1971 W. 5. ZXMKT MARSHALL LAB. COMHEHTS OH LETTER FROM KPVLA TO ERA In itea (1) I think we should ask# a stronger argument for reinstatement of ths 85% reduction clause. If you use Appendix J to compute the aaount of hydrocarbon reduction needed* to meet the oxidant standard* you see that an 85% hydrocarbon reduction is considered sufficient to reduce to an acceptable level original photochemical oxidant concentrations of as much as 500 ug./S? (0.25 ppm.). Itea (3) could be worded more clearly to eaphaslse the "corrected for methane" part of the definition. Is item (8) still necessary! The Standards pub lished April 30* 1971* have quite clearly defined the method of analysis to be used for measurement of pollutants. X doubt that anyone would use a different method for the early sampling (July 1, 1971* to September 30* 1971) unless the apparatus and trained personnel are not available to utilise the "approved" method. Some statement should be added to item (9) to the effeet that* avaa though we coneider Appendix J invalid* if it ie going to be uaedb it should be redrawn to refloat the higher photochemical oxidant standard of loO ug./sP. (The curve should bt shifted to the right). WWK/pe WILLIAM W. POLCOTXOll COSTROL COORDXHAXOR N38438