Annual Average Concentrations and Health Risks																			
TAC	Conc.1/Risk2	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007
Acetaldehyde	Annual Avg														0.84	0.82	0.78	0.82	0.73
	Health Risk														4	4	4	4	4
Benzene	Annual Avg														0.577	0.502	0.414	0.383	0.353
	Health Risk														53	46	38	36	33
"1,3-Butadiene"	Annual Avg														0.131	0.137	0.104	0.091	0.081
	Health Risk														49	51	39	34	31
Carbon Tetrachloride	Annual Avg														0.096				
	Health Risk														25				
"Chromium, Hexavalent"	Annual Avg														0.098	0.1		0.053	0.063
	Health Risk														15	15		8	9
para-Dichlorobenzene	Annual Avg														0.15	0.15	0.15	0.15	
	Health Risk														10	10	10	10	
Formaldehyde	Annual Avg														2.79	2.13	1.71	1.88	1.9
	Health Risk														21	16	13	14	14
Methylene Chloride	Annual Avg														0.19	0.16	0.13	0.14	0.15
	Health Risk														<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg														0.04	0.037	0.032	0.029	0.028
	Health Risk														2	1	1	1	1
Diesel PM	Annual Avg																		
	Health Risk																		
Total Health Risk															179	143	105	107	92






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