[Code of Federal Regulations]
[Title 40, Volume 8]
[Revised as of July 1, 2002] 
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR61.15]

[Page 36-37]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
               CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY
 
PART 61--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS--Table of Contents
 
                      Subpart A--General Provisions
 
Sec. 61.15  Modification.

    (a) Except as provided under paragraph (d) of this section, any 
physical or operational change to a stationary source which results in 
an increase in the rate of emission to the atmosphere of a hazardous 
pollutant to which a standard applies shall be considered a 
modification.
    (b) Upon modification, an existing source shall become a new source 
for each hazardous pollutant for which the rate of emission to the 
atmosphere increases and to which a standard applies.
    (c) Emission rate shall be expressed as kg/hr of any hazardous 
pollutant discharged into the atmosphere for which a standard is 
applicable. The Administrator shall use the following to determine the 
emission rate:
    (1) Emission factors as specified in the background information 
document (BID) for the applicable standard, or in the latest issue of 
``Compilation of Air Pollutant Emission Factors,'' EPA Publication No. 
AP-42, or other emission factors determined by the Administrator to be 
superior to AP-42 emission factors, in cases where use of emission 
factors demonstrates that the emission rate will clearly increase or 
clearly not increase as a result of the physical or operational change.
    (2) Material balances, monitoring data, or manual emission tests in 
cases where use of emission factors, as referenced in paragraph (c)(1) 
of this section, does not demonstrate to the Administrator's 
satisfaction that the

[[Page 37]]

emission rate will clearly increase or clearly not increase as a result 
of the physical or operational change, or where an interested person 
demonstrates to the Administrator's satisfaction that there are 
reasonable grounds to dispute the result obtained by the Administrator 
using emission factors. When the emission rate is based on results from 
manual emission tests or monitoring data, the procedures specified in 
appendix C of 40 CFR part 60 shall be used to determine whether an 
increase in emission rate has occurred. Tests shall be conducted under 
such conditions as the Administrator shall specify to the owner or 
operator. At least three test runs must be conducted before and at least 
three after the physical or operational change. If the Administrator 
approves, the results of the emission tests required in Sec. 61.13(a) 
may be used for the test runs to be conducted before the physical or 
operational change. All operating parameters which may affect emissions 
must be held constant to the maximum degree feasible for all test runs.
    (d) The following shall not, by themselves, be considered 
modifications under this part:
    (1) Maintenance, repair, and replacement which the Administrator 
determines to be routine for a source category.
    (2) An increase in production rate of a stationary source, if that 
increase can be accomplished without a capital expenditure on the 
stationary source.
    (3) An increase in the hours of operation.
    (4) Any conversion to coal that meets the requirements specified in 
section 111(a)(8) of the Act.
    (5) The relocation or change in ownership of a stationary source. 
However, such activities must be reported in accordance with 
Sec. 61.10(c).

[50 FR 46294, Nov. 7, 1985]