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RCRA Box 1883 

Prepped by Ollie Stewart 

Document Number: 

101) ll-B-263 

Docket Number: 

A-90-19 

Printed 12/3/200810:42:17 AM Sheet 101 ofl 71 
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RADIAN 

MEMORANDUM 

A-90-19 

ll-B-263 

DATE: 

SUBJECT: 

FROM: 

TO: 

February 14, 1992 

Nationa l Impacts Scalin g Procedur e fonl|,kvi|jlltocJ?C^P^fe j'lrr 

The HON Impacts Analysis JU^J ' ~""* S.'ll 

Bennet t King f' j

 $EP •' 4 /992 \\'i 

3 hr~-f 

Janet S. Meyer, EPA/SDB •S^^^KiT 

This memo describes the method used to develop estimates of 

national emissions and control impacts reflective of a given 

regulatory option for the level C chemical production processes 

(CPP's). Control impacts include emission reductions, costs, 

other environmental impacts, and increases in energy usage 

resulting from application of emission controls. 

Briefly, level C CPP's are those for which little 

information was available from the data gathering and engineering 

analysis processes. These are in contrast to level A and B CPP's 

for which much better information was available and for which 

estimates of emissions and control impacts were made using a 

model emission source approach. The difference between level A, 

B, & C CPP's is described in detail in the memo titled "HON SOCMI 

Characterization." The model emission source approach for 

estimating emissions and control impacts is described in the 

Hazardous Organic NESHAP (HON) background information document 

(BID), Volume IA, Chapter 4, Estimation Methodology. Estimates 

for level A CPP's were relied on in developing estimates for the 

level C CPP's. 

Based on the results of the SOCMI characterization , level C 

CPP's are believed to be manufacturing processes for small 

production volume specialty chemicals. National production 

capacity information was available for some level C CPP's. It 

showed a mean production capacity of 11.62 Gg/yr and a range from 

.000227 Gg/yr to 179 Gg/yr. For purposes of the impacts 

analysis, it was assumed that the entire national production 

capacity for each level C CPP was produced at a single process 

unit. The known values of production capacity for level C CPP's 
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I 

overlapped with the smallest 5 percent of the level A process 

units which have a mean production capacity of 12.96 Gg/yr and a 

range from .000225 Gg/yr to 36.29 Gg/yr. Therefore, it was 

concluded that impacts estimates that had been developed for 

small level A process units could be used to estimate impacts for 

level C CPP's. 

National emissions and control impacts were estimated for 

the five kinds of emission points regulated in the HON: process 

vents, storage tanks, transfer loading operations, equipment 

leaks, and wastewater collection and treatment operations. The 

portion of national impacts attributable to the level C CPP's was 

estimated independently for each kind of emission point using a 

two-step process for each regulatory option. In the first step, 

average values for emissions and control impacts reflective of a 

given regulatory option are calculated. In the second step, the 

number of level C process units expected to have to apply 

emission controls under a given regulatory option was determined, 

and the average values for control impacts determined in the 

first step were assigned to this set of process units. This 

procedure was judged to develop representative estimates of 

national impacts. However, it does produce a different estimate 

of baseline emissions for each regulatory alternative. Further, 

the national percent of emission reduction achieved as compared 

to the information used for decision-making (emissions and 

control impacts for level A CPP's only) is distorted because a 

different subset of emission points are used to develop average 

values of emissions and control impacts for each regulatory 

option. These two steps are described below. 

Step 1: Average emissions and control impacts values for 

level C CPP's were based on the average estimates for 

the smallest 5 percent of level A process units. Based 

on the similarity in production capacity values, 

relying on the estimates of emissions and control 

impacts for the smallest 5 percent of the level A 

process units for developing estimates for the level C 

CPP's (process units) was judged to provide reasonably 
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representative values. Only process units that would 

be required to apply additional control for the 

specific emission source type under a given regulatory 

option were used in calculating the average values. 

This restriction provides different average values for 

emissions and control impacts for different regulatory 

options and resulted in values better reflecting the 

given regulatory option. If process units without 

control impacts (i.e., those not required to apply 

additional controls) were used, calculation of the 

average impacts per process unit would be diluted with 

a number of process units contributing zero to the 

numerator (impacts) but being included in the 

denominator (number of process units). This would 

result in unrealistically low (or zero) values for 

average control impacts. This procedure, however, 

produced different estimates of baseline emissions for 

each regulatory option. 

Step 2: Average emissions and control impacts were not applied 

to all level C process units. Regulatory options did 

not require control of all emission points. In fact, 

under most options, the smaller emission points were 

not required to apply controls. Therefore, average 

emissions and control impacts were assigned to a subset 

of the level C emission points. Because regulatory 

option criteria (e.g., tank size and chemical vapor 

pressure for storage tanks) was not available for 

level C emission points, they could not be evaluated 

for inclusion or exclusion under a regulatory option in 

the same manner as level A emission points. Therefore, 

the number of level C emission points that would be 

required to apply emission control compared to the 

total number of level C emission points was assumed to 

be in the same proportion as for level A emission 

points for any given regulatory option. For example, 

if 70 percent of the level A emission points were 
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«A 

required by a particular regulatory option to apply 

control, it was assumed the 70 percent of the level C 

emission points would be required to apply control. 

For that fraction of level C emission points required 

to apply control under a given option, the control 

impacts were set equal to the average values for the 

smallest 5 percent of the level A emission points (see 

Step 1). For that fraction of level C emission points 

not required to apply control under a given regulatory 

option, the control impacts were estimated to be zero. 

BK/als/LevelC.014 
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'_*< • 

REFERENCES 

Memorandum from King, B. S., Radian Corporation, to Meyer, 

J. S., EPA/SDB. HON SOCMI Characterization. 

February 14, 1992.