[Code of Federal Regulations]

[Title 40, Volume 28]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR423.11]



[Page 645-646]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 423_STEAM ELECTRIC POWER GENERATING POINT SOURCE CATEGORY--Table of 

Contents

 

Sec.  423.11  Specialized definitions.



    In addition to the definitions set forth in 40 CFR part 401, the 

following definitions apply to this part:

    (a) The term total residual chlorine (or total residual oxidants for 

intake water with bromides) means the value obtained using the 

amperometric method for total residual chlorine described in 40 CFR part 

136.

    (b) The term low volume waste sources means, taken collectively as 

if from one source, wastewater from all sources except those for which 

specific limitations are otherwise established in this part. Low volume 

wastes sources include, but are not limited to:



[[Page 646]]



wastewaters from wet scrubber air pollution control systems, ion 

exchange water treatment system, water treatment evaporator blowdown, 

laboratory and sampling streams, boiler blowdown, floor drains, cooling 

tower basin cleaning wastes, and recirculating house service water 

systems. Sanitary and air conditioning wastes are not included.

    (c) The term chemical metal cleaning waste means any wastewater 

resulting from the cleaning of any metal process equipment with chemical 

compounds, including, but not limited to, boiler tube cleaning.

    (d) The term metal cleaning waste means any wastewater resulting 

from cleaning [with or without chemical cleaning compounds] any metal 

process equipment including, but not limited to, boiler tube cleaning, 

boiler fireside cleaning, and air preheater cleaning.

    (e) The term fly ash means the ash that is carried out of the 

furnace by the gas stream and collected by mechanical precipitators, 

electrostatic precipitators, and/or fabric filters. Economizer ash is 

included when it is collected with fly ash.

    (f) The term bottom ash means the ash that drops out of the furnace 

gas stream in the furnace and in the economizer sections. Economizer ash 

is included when it is collected with bottom ash.

    (g) The term once through cooling water means water passed through 

the main cooling condensers in one or two passes for the purpose of 

removing waste heat.

    (h) The term recirculated cooling water means water which is passed 

through the main condensers for the purpose of removing waste heat, 

passed through a cooling device for the purpose of removing such heat 

from the water and then passed again, except for blowdown, through the 

main condenser.

    (i) The term 10 year, 24/hour rainfall event means a rainfall event 

with a probable recurrence interval of once in ten years as defined by 

the National Weather Service in Technical Paper No. 40. Rainfall 

Frequency Atlas of the United States, May 1961 or equivalent regional 

rainfall probability information developed therefrom.

    (j) The term blowdown means the minimum discharge of recirculating 

water for the purpose of discharging materials contained in the water, 

the further buildup of which would cause concentration in amounts 

exceeding limits established by best engineering practices.

    (k) The term average concentration as it relates to chlorine 

discharge means the average of analyses made over a single period of 

chlorine release which does not exceed two hours.

    (l) The term free available chlorine shall mean the value obtained 

using the amperometric titration method for free available chlorine 

described in Standard Methods for the Examination of Water and 

Wastewater, page 112 (13th edition).

    (m) The term coal pile runoff means the rainfall runoff from or 

through any coal storage pile.