Comment Log Display

I work for a company that will need to meet the requirements of the
ARB's new Truck and Bus Rule.  I have examined the language and
numbers of the proposed regulation and have found some numbers that
seem to be incorrect.  

The numbers in the fleet calculator further prove my point.  The
numbers are such that no HHD truck older than Engine Model Year
2007 will ever meet the required PM emissions target of .110
g/mile, even with a DPF that cuts emissions by 85%.  As shown in
the attached file "Fleet Calc Error PM 2.xls," all of the trucks
with Engine MY1994-2006 will only reach .122 g/mile of PM.  The
Fleet Calculator shows that a fleet of MY1994-2006 engines will
meet BACT 100%, but the numbers do not show that.

On the opposite end of the spectrum, I can insert an incredibly
old Engine Model Year (MY1923 in "Fleet Calc Error PM 1.xls") into
the calculator and still return 100% BACT compliance even though
the Fleet Average PM level would be .504 g/mile.

As for the NOx emissions, the greatest reduction as required by
the Truck and Bus Rule will only get a MY2006 Engine (85% NOx
reduction) down to 1.80 g/mile of NOx (see "Fleet Calc Error NOx
1.xls") .  The NOx target is below that number at 1.60 g/mile NOx. 


In fact, in the "Fleet Calc Error NOx 2.xls" file even a MY2011
Engine will not meet MY2010 emissions requirements, as the numbers
show that it still emits 2.50 g/mile NOx.

The numbers must be addressed before this rule is approved.  As it
currently stands, the ARB's numbers for calculating Emissions
Targets and Averages are conflicting in the both the language of
the rule and the fleet calculators.  I believe that one way to
repair this conflict is to change the numbers in the Appendix A
section of the rule (page A-45).  (For instance, in Table A-1 of
Appendix A, MY1994-2006 HHD should change the PM emissions factor
from 0.81 to 0.73).  If the numbers stay the same, then the ARB
will have to require further PM and NOx reduction from filters that
are already required to eliminate 85% of PM emissions and 20-85% of
NOx emissions.

Please consider these conflicts when you meet to finalize your
regulation.  These types of errors could create immense problems
with the implementation of the ARB regulation and require a
complete overhaul of the rule.

Thank you.