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	1.53	1.55	1.41	1.58	1.27	0.35	1.04	0.97	0.77	0.93	0.79	0.76						
	Health Risk	7	8	7	8	6	2	5	5	4	4	4	4						
Benzene	Annual Avg	3.02	2.44	2.03	1.89	1.88	1.55	0.97	0.93	1.04	0.73	0.7							
	Health Risk	280	226	188	175	174	144	89	86	97	68	65							
"1,3-Butadiene"	Annual Avg	0.549	0.385	0.436	0.485	0.385	0.348	0.311	0.287	0.293	0.227	0.193							
	Health Risk	207	145	164	182	145	131	117	108	110	85	72							
Carbon Tetrachloride	Annual Avg	0.127	0.128		0.107		0.102	0.077				0.095							
	Health Risk	33	34		28		27	20				25							
"Chromium, Hexavalent"	Annual Avg			0.29	0.25	0.25	0.33	0.17	0.13	0.11	0.1	0.13							
	Health Risk			43	37	38	49	25	20	17	15	19							
para-Dichlorobenzene	Annual Avg			0.12	0.12	0.1	0.12	0.14	0.12			0.12							
	Health Risk			8	8	7	8	10	8			8							
Formaldehyde	Annual Avg	2.27	2	2.09	1.83	2.16	2.28	2.7	2.56	2.24	2.69	2.24	2.27						
	Health Risk	17	15	15	13	16	17	20	19	16	20	16	17						
Methylene Chloride	Annual Avg	0.83	6.65	0.66	0.58	0.8	0.69	0.55	0.75			0.5							
	Health Risk	3	23	2	2	3	2	2	3			2							
Perchloroethylene	Annual Avg	0.161	0.153	0.1	0.094	0.064	0.069	0.068	0.096			0.088							
	Health Risk	6	6	4	4	3	3	3	4			4							
Diesel PM	Annual Avg																		
	Health Risk																		
Total Health Risk		553	457	431	457	392	383	291	253	244	192	215	21						






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