2002 Almanac (page 372)  Table A-59  Northeast Plateau - Modoc County - Air Quality Trends																				

OZONE (ppm)	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Peak 1-Hour Indicator																				
National 1-Hr. Design Value																				
Nat. 8-Hr. Design Value																				
Maximum 1-Hr. Concentration																				
Max. 8-Hr. Concentration																				
Days Above State Standard																				
Days Above Nat. 1-Hr. Std.																				
Days Above Nat. 8-Hr. Std.																				

PM10 (ug/m3)	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Max. 24-Hour Concentration														101	78	74	97	62	94	79
Max. Annual Geometric Mean																			22.2	17.6
Calc Days Above State 24-Hr Std														18	54	12	6	12	30	18
Calc Days Above Nat 24-Hr Std														0	0	0	0	0	0	0

CARBON MONOXIDE (ppm)	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Peak 8-Hr. Indicator																				
Max. 1-Hr. Concentration																				
Max. 8-Hr. Concentration																				
Days Above State 8-Hr. Std.																				
Days Above Nat. 8-Hr. Std.																				

NITROGEN DIOXIDE (ppm)	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Peak 1-Hr. Indicator																				
Max. 1-Hr. Concentration																				
Max. Annual Average																				

SULFUR DIOXIDE (ppm)	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000
Peak 1-Hr. Indicator																				
Max. 24-Hr. Concentration
Max. Annual Average