Mr. Taylor:
1)  The allowable data is generally unique to each permit.  Because of this a general statement like "the allowable tons/year for SO2 in Harris County is ......." would not be defendable or valid.  
2)  I believe that the allowable data varies in relation to the season of year and part of the state - a.k.a., "ambient background threshold".   In other words, if it is ozone season, allowable emissions probably would be lower.  
3)  The allowable emissions threshold is also variable over time.  25 years ago, Harris county probably did not need an allowable cap for certain emissions.  As industry grows the allowable emissions will be adjusted.  The period of time for the data to become outdated could be as little as 1 month, depending on when new allowables or new permits are initiated.  
4)  Texas charges corporations a "tax" for emissions over their allowable limit.  It is sort of a pay-as-you-go plan.  Of course I am being very simplistic here, but the point is still the same.  

Your questions are excellent and I am giving you as specific an answer as possible.  I hope I am not being too pointed but to the data oriented person, the previous points are important for data integrity.  Jim Parks 


>>> "Taylor, Michael E" <Michael.E.Taylor@ENRON.com> 08/23/01 03:10PM >>>
Jim,

Could you please explain to me where these numbers would NOT be
accurate?  I was warned that the data (allowables) would not be 100%
accurate because of certain reasons.  Can you please detail those
reasons for me?

Michael Taylor
Coal and Emissions Trading
Enron Global Markets
(713) 853-1885





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