From:	Bradley Nelson [nelson.brad@ecrweb.com]
Sent:	Friday, February 05, 2010 10:30 AM
To:	King.Melanie@epamail.epa.gov
Cc:	'Tanya Parise'; fitzsimons.graham@ecrweb.com
Subject:	Urban/Rural Designations for 2002 NEI Engines
Attachments:	RICE U1U2.xls

Melanie,

I have attached a spreadsheet that provides the counts for the U1/U2/Rural designations for the reciprocating 
internal combustion engines extracted from the 2002 NEI database by fuel type.  The designations are based 
on the following U.S. Bureau of Census definitions and were obtained from the EPA TTN Air Toxics website 
http://www.epa.gov/airtoxics/urban/pop1u_r.pdf .  

• Urban-1 (U1) counties that include a metropolitan statistical area (MSA) with a population greater than 
250,000; 
• Urban-2 (U2) counties that do not include a MSA with a population greater than 250,000, but the Bureau of 
Census designates more than 50 percent of the county population as urban; and 
• Rural (R) counties that do not include a MSA with a population greater than 250,000, and the Bureau of 
Census designates more than 50 percent of the county population as rural.

The engine inventory data was extracted from the 2002 NEI database by querying the database using 
SCC codes for reciprocating internal combustion engines (e.g., 201-XX-XXX, 202-XX-XXX, 203-XX-XXX).  
The query provided data for the following fields from the 2002 NEI database:  FIPS code, State Facility 
ID, NEI ID, Facility Name, Site Description, SCC code, NAICS code, SIC code, Latitude, Longitude, Unit 
ID, Capacity Information, Control Device Description, and Emission Release Point ID.  Of the 44,088 
records that were extracted from the 2002 NEI database, only 39,235 were unique engines that 
provided both latitude and longitude information.  A subset of the unique engine data containing the 
following fields: NEI ID, Unit ID, SCC code, latitude, and longitude fields was extracted from the NEI 
query information and input into ArcGIS.  The ArcGIS program mapped the engines using the 
latitude/longitude information onto a shape file of the U.S. county designations for U1, U2, and Rural. 
 The ArcGIS designation results were then sorted by fuel type and U1/U2/Rural designations to obtain 
a count of the engines in each of the categories.  The attached spreadsheet provides the total 
inventory of unique engines from the 2002 NEI database that were designated U1/U2/Rural and a 
summary of the U1/U2/Rural designations by fuel type. 


Bradley W. Nelson
EC/R Incorporated
501 Eastowne Drive, Suite 250
Chapel Hill, NC 27514
(919) 484-0222 x323
Fax: 919-484-0122 
nelson.brad@ecrweb.com
http://www.ecrweb.com/

