[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: 40CFR57.404]

[Page 146-147]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 57--PRIMARY NONFERROUS SMELTER ORDERS--Table of Contents
 
          Subpart D--Supplementary Control System Requirements
 
Sec. 57.404  Measurements, records, and reports.

    (a) Measurements. Each NSO shall require the smelter owner to 
install, operate, and maintain a measurement system(s) for continuously 
monitoring sulfur dioxide emissions and stack gas volumetric flow rates 
in each stack (except a stack used exclusively for bypassing control 
equipment) which could emit 5 percent or more of the smelter's total 
potential (uncontrolled) hourly sulfur dioxide emissions.
    (1) Such monitors shall be installed, operated, and maintained in 
accordance with the performance specifications and other requirements 
contained in appendices D and E to 40 CFR part 52. The monitors must 
take and record at least one measurement of sulfur dioxide concentration 
and stack gas flow rate from the effluent of each affected stack in each 
fifteen-minute period. (The NSO shall require the smelter operator to 
devise and implement any procedures necessary for compliance with these 
performance specifications.)
    (2) The sampling point shall be located at least eight stack 
diameters (diameter measured at sampling point) downstream and two 
diameters upstream from any flow disturbance such as a bend, expansion, 
constriction, or

[[Page 147]]

flame, unless another location is approved by the Administrator.
    (3) The sampling point for monitoring emissions shall be in the duct 
at the centroid of the cross section if the cross sectional area is less 
than 4.645 m2 (50 ft 2) or at a point no closer to 
the wall than 0.914m (3 ft) if the cross sectional area is 4.645 
m2 (50 ft2) or more. The monitor sample point 
shall be in an area of small spatial concentration gradient and shall 
provide a sample which is representative of the concentration in the 
duct.
    (4) The measurement system(s) installed and used pursuant to this 
paragraph shall be subject to the manufacturer's recommended zero 
adjustment and calibration procedures at least once per 24-hour 
operating period unless the manufacturer specifies or recommends 
calibration at shorter intervals, in which case such specifications or 
recommendations shall be followed. Records of these procedures shall be 
made which clearly show instrument readings before and after zero 
adjustment and calibration.
    (5) The results of such monitoring, calibration, and maintenance 
shall be submitted in the form and with the frequency specified in the 
NSO.
    (b) Records. Each NSO shall require the smelter owner to maintain 
records of the air quality measurements made, meteorological information 
acquired, emission curtailment ordered (including the identity of the 
persons making such decisions), and calibration and maintenance 
performed on SCS monitors during the operation of the SCS. These records 
shall be maintained for the duration of the NSO.
    (c) Reports. Each NSO shall require the smelter owner to:
    (1) Submit a monthly summary indicating all places and times at 
which the NAAQS for SO2 were violated in the smelter's DLA, 
and stating the SO2 concentrations at such times;
    (2) Immediately notify EPA and the State agency any time 
concentrations of SO2 in the ambient air in the smelter's DLA 
reaches 0.3 part per million (800 micrograms/cubic meter), 24-hour 
average, or exceed the warning stage in any more stringent emergency 
plan in the applicable State Implementation Plan; and
    (3) Make such other reports as may be specified in the NSO.