2002 Almanac (page 460)  Table C-20 Sacramento Valley Air Basin:  Annual Average Concentrations and Health Risks by Site																							
																							
		Annual Average Concentration*											Health Risk**										
COUNTY / SITE	TAC	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
BUTTE Chico-Manzanita Avenue	Acetaldehyde				1.55	1.11	0.54	1.15	1.17	0.96	1.41	0.89				8	5	3	6	6	5	7	4
	Benzene				1.10	1.14	0.85	0.67		0.55	0.64	0.52				102	106	78	62		51	59	48
	"1,3-Butadiene"				0.30	0.25	0.21	0.22		0.17	0.15	0.14				111	94	77	81		64	56	54
	Carbon Tetrachloride				0.11		0.10	0.08								29		26	21				
	Chromium (Hexavalent)				0.15	0.13	0.16	0.10	0.10	0.10	0.10	0.10				23	19	24	16	15	15	15	15
	para-Dichlorobenzene				0.10	0.13	0.10	0.12								7	8	7	8				
	Formaldehyde				2.08	1.78	2.04	2.99	3.42	2.63	4.15	2.76				15	13	15	22	25	19	31	20
	Methylene Chloride				0.81	0.50	0.53	0.58								3	2	2	2				
	Perchloroethylene				0.06	0.27	0.05	0.05								2	11	2	2				
	Diesel PM	No Monitoring Data Available																					
Total Health Risk																							
																							
BUTTE Chico-Salem Street	Acetaldehyde	1.27											6										
	Benzene	1.96	1.91										182	177									
	"1,3-Butadiene"	0.40	0.36										151	136									
	Carbon Tetrachloride	0.12	0.12										32	33									
	Chromium (Hexavalent)																						
	para-Dichlorobenzene																						
	Formaldehyde	1.49											11										
	Methylene Chloride	0.53	0.57										2	2									
	Perchloroethylene	0.05	0.05										2	2									
	Diesel PM	No Monitoring Data Available																					
Total Health Risk																							
																							
PLACER Roseville-North Sunrise Blvd	Acetaldehyde					0.96	0.25	0.90	0.93	0.88		0.77					5	1	4	4	4		4
	Benzene					0.91	0.75	0.44	0.46	0.45	0.48	0.39					84	70	40	42	42	44	36
	"1,3-Butadiene"					0.19	0.17	0.14	0.12	0.14	0.11	0.10					73	63	51	46	52	40	36
	Carbon Tetrachloride						0.10	0.08				0.09						26	20				25
	Chromium (Hexavalent)					0.13	0.19	0.11	0.10	0.10	0.10	0.10					19	29	16	15	15	15	15
	para-Dichlorobenzene					0.28	0.17	0.10	0.15			0.10					19	11	7	10			7
	Formaldehyde					1.71	1.78	2.52	2.42	2.42		2.25					13	13	19	18	18		17
	Methylene Chloride					0.82	0.54	0.50	0.50			0.52					3	2	2	2			2
	Perchloroethylene					0.07	0.05	0.06	0.06			0.05					3	2	2	3			2
	Diesel PM	No Monitoring Data Available																					
Total Health Risk																							
																							
SACRAMENTO Citrus Heights-Sunrise Blvd	Acetaldehyde	1.32											6										
	Benzene	2.08	1.85	1.41									192	171	130								
	"1,3-Butadiene"	0.35	0.30	0.31									133	114	115								
	Carbon Tetrachloride	0.12	0.12										33	32									
	Chromium (Hexavalent)																						
	para-Dichlorobenzene			0.11											7								
	Formaldehyde	1.66											12										
	Methylene Chloride	0.76	0.54	0.50									3	2	2								
	Perchloroethylene	0.10	0.09	0.08									4	4	3								
	Diesel PM	No Monitoring Data Available																					
Total Health Risk																							
																							
BASIN SUMMARY	Acetaldehyde	1.29			1.37	1.04	0.39	1.03	1.05	0.92	1.23	0.83	6			7	5	2	5	5	4	6	4
	Benzene	2.02	1.88	1.35	1.00	1.02	0.80	0.56	0.55	0.50	0.56	0.45	187	174	125	92	95	74	51	51	47	52	42
	"1,3-Butadiene"	0.38	0.33	0.28	0.29	0.22	0.19	0.18	0.16	0.15	0.13	0.12	142	125	106	108	83	70	66	60	58	48	45
	Carbon Tetrachloride	0.12	0.12		0.11		0.10	0.08				0.09	33	32		29		26	21				25
	Chromium (Hexavalent)			0.17	0.14	0.13	0.18	0.11	0.10	0.10	0.10	0.10			26	21	19	26	16	15	15	15	15
	para-Dichlorobenzene			0.11	0.10	0.20	0.14	0.11	0.14			0.10			7	7	14	9	7	10			7
	Formaldehyde	1.57			1.77	1.75	1.91	2.76	2.92	2.52	3.61	2.51	12			13	13	14	20	22	19	27	18
	Methylene Chloride	0.65	0.56	0.55	0.98	0.66	0.53	0.54	0.52		0.60	0.57	2	2	2	3	2	2	2	2		2	2
	Perchloroethylene	0.07	0.07	0.06	0.05	0.17	0.05	0.06	0.05			0.06	3	3	3	2	7	2	2	2			2
	Diesel PM***	2.5					1.6					1.2	750					480					360
Average Basin Health Risk													385	336	269	282	238	225	190	167	144	150	160

*     Concentrations for Chromium (Hexavalent) are expressed as ng/m3 and concentrations for Diesel PM are expressed as ug/m3. Concentrations for all other TACs are expressed as parts per billion.
**   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.
"***  The Diesel PM concentrations are estimates based on receptor modeling. Because data are not available for all years, Diesel PM is not included in the Average Basin Health Risk number. "