[Code of Federal Regulations]
[Title 40, Volume 5]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR58.13]

[Page 209-210]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 58--AMBIENT AIR QUALITY SURVEILLANCE--Table of Contents
 
                     Subpart B--Monitoring Criteria
 
Sec. 58.13  Operating schedule.

    Ambient air quality data collected at any SLAMS must be collected as 
follows:
    (a) For continuous analyzers--consecutive hourly averages except 
during:
    (1) Periods of routine maintenance,
    (2) Periods of instrument calibration, or
    (3) Periods or seasons exempted by the Regional Administrator.
    (b) For manual methods (excluding PM10 samplers, 
PM2.5 samplers, and PAMS VOC samplers), at least one 24-hour 
sample must be obtained every sixth day except during periods or seasons 
exempted by the Regional Administrator.
    (c) For PAMS VOC samplers, samples must be obtained as specified in 
sections 4.3 and 4.4 of appendix D to this part. Area-specific PAMS 
operating schedules must be included as part of the network description 
required by Sec. 58.40 and must be approved by the Administrator.
    (d) For PM10 samplers--a 24-hour sample must be taken a 
minimum of every third day, except during periods or seasons exempted by 
the Regional Administrator.
    (e) For PM2.5 samplers, a 24-hour sample is required 
everyday for certain core SLAMS, including certain PAMS, as described in 
section 2.8.1.3 of appendix D of this part, except during seasons or 
periods of low PM2.5 as otherwise exempted by the Regional 
Administrator. A waiver of the everyday sampling schedule for SLAMS may 
be granted by the Regional Administrator or designee, and for NAMS by 
the Administrator or designee, for 1 calendar year from the time a 
PM2.5 sequential sampler (FRM or Class I equivalent) has been 
approved by EPA. A 24-hour sample must be taken a minimum of every third 
day for all other SLAMS, including NAMS, as described in section 2.8.1.3 
of appendix D of this part, except when exempted by the Regional 
Administrator in accordance with

[[Page 210]]

forthcoming EPA guidance. During periods for which exemptions to every 
third day or every day sampling are allowed for core PM2.5 
SLAMS, a minimum frequency of one in 6-day sampling is still required. 
However, alternative sampling frequencies are allowed for SLAMS sites 
that are principally intended for comparisons to the 24-hour NAAQS. Such 
modifications must be approved by the Regional Administrator.
    (f) Alternatives to everyday sampling at sites with correlated 
acceptable continuous analyzers. (1) Certain PM2.5 core SLAMS 
sites located in monitoring planning areas (as described in section 2.8 
of appendix D of this part) are required to sample every day with a 
reference or equivalent method operating in accordance with part 53 of 
this chapter and section 2 of appendix C of this part. However, in 
accordance with the monitoring priority as defined in paragraph (f)(2) 
of this section, established by the control agency and approved by EPA, 
a core SLAMS monitor may operate with a reference or equivalent method 
on a 1 in 3-day schedule and produce data that may be compared to the 
NAAQS, provided that it is collocated with an acceptable continuous fine 
particulate PM analyzer that is correlated with the reference or 
equivalent method. If the alternative sampling schedule is selected by 
the control agency and approved by EPA, the alternative schedule shall 
be implemented on January 1 of the year in which everyday sampling is 
required. The selection of correlated acceptable continuous PM analyzers 
and procedures for correlation with the intermittent reference or 
equivalent method shall be in accordance with procedures approved by the 
Regional Administrator. Unless the continuous fine particulate analyzer 
satisfies the requirements of section 2 of appendix C of this part, 
however, the data derived from the correlated acceptable continuous 
monitor are not eligible for direct comparisons to the NAAQS in 
accordance with part 50 of this chapter.
    (2) A Metropolitan Statistical Area (MSA) (or primary metropolitan 
statistical area) with greater than 1 million population and high 
concentrations of PM2.5 (greater than or equal to 80 percent 
of the NAAQS) shall be a Priority 1 PM monitoring area. Other monitoring 
planning areas may be designated as Priority 2 PM monitoring areas.
    (3) Core SLAMS having a correlated acceptable continuous analyzer 
collocated with a reference or equivalent method in a Priority 1 PM 
monitoring area may operate on the 1 in 3 sampling frequency only after 
reference or equivalent data are collected for at least 2 complete 
years.
    (4) In all monitoring situations, with a correlated acceptable 
continuous alternative, FRM samplers or filter-based equivalent 
analyzers should preferably accompany the correlated acceptable 
continuous monitor.

[44 FR 27571, May 10, 1979, as amended at 52 FR 24739, July 1, 1987; 58 
FR 8467, Feb. 12, 1993; 62 FR 38831, July 18, 1997; 63 FR 7714, Feb. 17, 
1998]