Review of the Air Quality Criteria Document for Particulate Matter

the data in Figure 4-24 end in 1992, it is hard to justify open-ended statements like “Thehaziness over the Gulf states increased between 1960 and 1970 and remained virtuallyunchanged since then.”4.3.9 Economics of PM visibility effects: Here, finally, is a subsection that does not justrehash and garble the corresponding 1996 account. Unfortunately, the new accountseems inconsistent with the old, and the disagreement is nowhere acknowledged.According to the 2001 review (P 4-114, L 2), “The results indicate a willingness to payper deciview improvement in visibility [in class I areas, capturing both use and nonuserecreational values] of between $5 and $17 per household.” According to the 1996review (Table 8-6), the willingness to pay per deciview improvement in urban visibilityranged from $8 to $231 per household (in older, more valuable dollars), with a median ofabout $100. If visibility is really worth that much more in cities than in National Parks,then why are almost all our visibility monitors in Parks? I couldn’t find the $5 - $17values in the cited reference, so I suspect that this is yet another instance of garbledreporting.The bottom line for section 4.3 is that no coherent attempt is made to connect visibility with thehealth-based PM indicator.A curious omissionThe single most important visibility development since the 1996 CD has been the arrival ofRegional Haze Rules. These Rules establish a framework for regulating visibility that anysecondary PM standard will have to coexist with. Whereas any secondary standard will requirescientific review by CASAC, the Regional Haze Rules already in effect were developed largelyfrom an administrative/bookkeeping perspective. How does the Regional Haze bookkeepingsquare with the science reviewed by the CD? This is a question the draft studiously ignores.George T. Wolff, PhDChapter 11. p 1-8, lines 4 – 5 – Is this something new? CASAC has not had an opportunity to commentcollectively on the proposals in the past.2. p 1-14, lines 1 – 2 – Does this mean that higher concentration studies that show no effectwere ignored?Chapter 2General – The chapter needs a glossary.1. p 2-15, lines 2-6 – This appears to be worded too strongly given the conclusions reached inchapter 6 (see page 6-266, lines 29-30).2. p 2-18, line 23 – The photolysis of O 3 is the major source of OH only in relatively pristineatmospheres. The major source in urban atmospheres is likely organic gases.3. P 2-19, lines 1-5 – This is also too strongly worded for the same reasons as 1.4. P 2-20, lines 1-3 – While this statement is true for sulfates, it is not for nitrates. Because ofthermal decomposition at high ambient temperatures, nitrates particles tend to be higher inthe winter.5. P 2-33, line 16 – I would remove the word “significantly” since droplet acidity is dominatedby in cloud formation and acid gas scavenging. Same comment for p 2-101, line 15.A - 85