Appendix C	San Bernardino County: Fontana - Arrow Highway Air Quality and Health Risk													Table C-24		

Annual Average Concentrations and Health Risks																
TAC	Conc.*/Risk**	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004
Acetaldehyde	Annual Avg															
	Health Risk															
Benzene	Annual Avg									0.98						
	Health Risk									91						
"1,3-Butadiene"	Annual Avg									0.244						
	Health Risk									92						
Carbon Tetrachloride	Annual Avg									0.114						
	Health Risk									30						
"Chromium, Hexavalent"	Annual Avg															
	Health Risk															
para-Dichlorobenzene	Annual Avg															
	Health Risk															
Formaldehyde	Annual Avg															
	Health Risk															
Methylene Chloride	Annual Avg									0.59						
	Health Risk									2						
Perchloroethylene	Annual Avg									0.179						
	Health Risk									7						
Diesel PM	Annual Avg	No Monitoring Data Available														
	Health Risk															
Total Health Risk 										222						

"*    Concentrations for Hexavalent Chromium are expressed as ng/m3, and concentrations for Diesel PM are expressed as ug/m3.  Concentrations for all other TACs are expressed as ppb."																
**  Health Risk represents the number of excess cancer cases per million people based on a lifetime (70-year) exposure to the annual average concentration.  Total Health Risk represents only those compounds listed in																
this table and only those with data for that year.  There may be other significant compounds for which monitoring and/or health risk information are not available.