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	1.32				0.98	0.4		0.75	0.54			0.57	0.54	0.68	0.69	0.65	0.54	0.44
	Health Risk	6				5	2		4	3			3	3	3	3	3	3	2
Benzene	Annual Avg		1.49	1.25		1.07	0.95	0.53	0.51	0.63	0.65	0.48	0.376		0.386	0.329	0.23	0.299	0.223
	Health Risk		138	116		99	88	49	48	59	61	45	35		36	30	21	28	21
"1,3-Butadiene"	Annual Avg		0.252	0.234		0.259	0.226	0.181	0.165	0.215	0.173	0.128	0.113		0.084	0.083	0.053	0.063	0.048
	Health Risk		95	88		97	85	68	62	81	65	48	42		32	31	20	24	18
Carbon Tetrachloride	Annual Avg		0.124				0.1	0.078				0.095	0.087		0.094				
	Health Risk		33				26	21				25	23		25				
"Chromium, Hexavalent"	Annual Avg				0.19	0.18	0.25	0.12	0.13	0.1		0.12		0.088	0.145	0.13	0.11	0.105	0.065
	Health Risk				29	26	37	18	19	15		18		13	22	20	17	16	10
para-Dichlorobenzene	Annual Avg		0.15	0.13		0.1	0.15	0.12	0.12			0.11	0.14		0.15	0.19	0.15	0.15	
	Health Risk		10	9		7	10	8	8			7	9		10	13	10	10	
Formaldehyde	Annual Avg	1.71				1.33	1.58		1.62	1.45			1.51	2.03	1.71	1.54	1.04	1.37	1.15
	Health Risk	13				10	12		12	11			11	15	13	11	8	10	8
Methylene Chloride	Annual Avg		3.22	0.88		0.6	0.63	0.66	0.5			0.6	0.26		0.17	0.17	0.12	0.14	0.11
	Health Risk		11	3		2	2	2	2			2	<1		<1	<1	<1	<1	<1
Perchloroethylene	Annual Avg		0.229	0.13		0.105	0.092	0.084	0.065			0.068	0.074		0.038	0.04	0.026	0.03	0.031
	Health Risk		9	5		4	4	3	3			3	3		1	2	1	1	1
Diesel PM	Annual Avg																		
	Health Risk																		
Total Health Risk		19	296	221	29	250	266	169	158	169	126	148	126	31	142	110	80	92	60






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