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				1.55	1.11	0.54	1.15	1.17	0.96	1.41	0.89	1.1	1.33	1.14	1.32	1.4	1	1.11
	Health Risk				8	5	3	6	6	5	7	4	5	6	6	6	7	5	5
Benzene	Annual Avg				1.1	1.14	0.85	0.67		0.55	0.64	0.52	0.499	0.544	0.449	0.533	0.427	0.297	0.284
	Health Risk				102	106	78	62		51	59	48	46	50	42	49	40	28	26
"1,3-Butadiene"	Annual Avg				0.295	0.249	0.205	0.216		0.17	0.149	0.142	0.157	0.154	0.111	0.132	0.108	0.057	0.06
	Health Risk				111	94	77	81		64	56	54	59	58	42	50	41	21	22
Carbon Tetrachloride	Annual Avg				0.108		0.1	0.079					0.088	0.087	0.093				
	Health Risk				29		26	21					23	23	24				
"Chromium, Hexavalent"	Annual Avg				0.15	0.13	0.16	0.1	0.1	0.1	0.1	0.1	0.1	0.058	0.048	0.075	0.058	0.038	0.03
	Health Risk				23	19	24	16	15	15	15	15	15	9	7	11	9	6	5
para-Dichlorobenzene	Annual Avg				0.1	0.13	0.1	0.12					0.13	0.15	0.15	0.15	0.15	0.15	
	Health Risk				7	8	7	8					9	10	10	10	10	10	
Formaldehyde	Annual Avg				2.08	1.78	2.04	2.99	3.42	2.63	4.15	2.76	3.25	4.47	3.82	3.4	3.28	2.63	2.82
	Health Risk				15	13	15	22	25	19	31	20	24	33	28	25	24	19	21
Methylene Chloride	Annual Avg				0.81	0.5	0.53	0.58					0.36	0.09	0.07	0.08	0.09	0.07	0.07
	Health Risk				3	2	2	2					1	<1	<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg				0.057	0.265	0.047	0.049					0.024	0.024	0.015	0.014	0.028	0.011	0.011
	Health Risk				2	11	2	2					<1	1	<1	<1	1	<1	<1
Diesel PM	Annual Avg																		
	Health Risk																		
Total Health Risk					300	258	234	220	46	154	168	141	182	190	159	151	132	89	79






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