2016-01-14_REVISION - M1983194 ‎(2)‎

• Permit No: M1983194
• IBM Index Class Name: Revision
• Doc Date: 1/14/2016
• Doc Name: Mine Plan Mod 500K TPY
• From: Natural Soda, LLC
• To: DRMS
• Email Name: THM
• Email Name: GRM
• Media Type: D
• Archive: No

Daub & Associates, Inc. Page 3-15 2015 NS Mine Plan Modification
1/5/2016 Section 3 General Site Conditions
NATIONAL AND COLORADO AMBIENT AIR QUALITY STANDARDS -
CRITERIA POLLUTANTS
Pollutant Standard
Type
Averaging
Period Level Form [final rule citation]
Carbon Monoxide primary 8-hour 9 ppm Not to be exceeded more than
once per year [76 FR 54294, Aug 31, 2011] 1-hour 35 ppm
Lead
primary
and
secondary
Rolling 3
month avg
0.15
μg/m3 (1)
Not to be exceeded
[73 FR 66964, Nov 12, 2008]
Nitrogen Dioxide primary 1-hour 100 ppb 98th percentile, averaged over 3
years [75 FR 6474, Feb 9, 2010]
[61 FR 52852, Oct 8, 1996]
primary
and
secondary
Annual 53 ppb (2) Annual Mean

Ozone primary
and
secondary
8-hour 0.075
ppm (3)
Annual fourth-highest daily
maximum
8-hr concentration, averaged over
3 years
[73 FR 16436, Mar 27, 2008]
Particulate Matter
PM2.5
primary Annual 12 μg/m3 Annual mean, averaged over 3
years
[73 FR 3086,
Jan 15, 2013] secondary Annual 15 μg/m3 Annual mean, averaged over 3
years
primary
and
secondary
24-hour 35 μg/m3 98th percentile, averaged over 3
years
PM10
primary
and
secondary
24-hour 150 μg/m3
Not to be exceeded more than
once per year, averaged over 3
years
Sulfur Dioxide
primary 1-hour 75 ppb (4)
99th percentile of 1-hour daily
maximum concentrations,
averaged over 3 years [75 FR 35520, Jun 22, 2010]
Colorado (State Only)
primary
and
secondary
3-hour 267 ppb Not to be exceeded in any 12
month period
[38 FR 25678, Sept 14,
1973] secondary 3-hour 0.5 ppm Not to be exceeded more than
once per year
Source: National- 40 CFR 50, Colorado-5CCR 1001-14.
μg/m3= micro grams per cubic meter, ppb = parts per billion, ppm = parts per million.
(1) Final rule signed October 15, 2008. The 1978 lead standard (1.5 µg/m3 as a quarterly average)
remains in effect until one year after an area is designated for the 2008 standard, except that in areas
designated nonattainment for the 1978, the 1978 standard remains in effect until implementation
plans to attain or maintain the 2008 standard are approved.
(2) The official level of the annual NO2 standard is 0.053 ppm, equal to 53 ppb, which is shown here
for the purpose of clearer comparison to the 1-hour standard.
(3) Final rule signed March 12, 2008. The 1997 ozone standard (0.08 ppm, annual fourth-highest
daily maximum 8-hour concentration, averaged over 3 years) and related implementation rules remain
in place. In 1997, EPA revoked the 1-hour ozone standard (0.12 ppm, not to be exceeded more than
once per year) in all areas, although some areas have continued obligations under that standard
(“anti-backsliding”). The 1-hour ozone standard is attained when the expected number of days per
calendar year with maximum hourly average concentrations above 0.12 ppm is less than or equal to 1.
(4) Final rule signed June 2, 2010. The 1971 annual and 24-hour SO2 standards were revoked in that
same rulemaking. However, these standards remain in effect until one year after an area is
designated for the 2010 standard, except in areas designated nonattainment for the 1971 standards,
where the 1971 standards remain in effect until implementation plans to attain or maintain the 2010
standard are approved.
Table 3-2. Colorado and Federal Air Quality Standards.4
4 Revised December 2015