C6-3. National Primary Drinking Water Regulations: Stage 2 Disinfectants and Disinfection Byproducts Rule

Correction

In rule document 06-3 beginning on page 388 in the issue of Wednesday, January 4, 2006, make the following corrections:

§141.131

[Corrected]

On page 481, in § 141.31(c)(1) the table is corrected to read as set forth below:

Methodology	SM (19th or 20th ed)	SM Online 2	ASTM method	EPA method	Residual measured 1
					Free Cl2	Combined Cl2	Total Cl2	ClO2
Amperometric Titration	4500-Cl D	4500-Cl D-00	D 1253-86 (96), 03		X	X	X
Low Level Amperometric Titration	4500-Cl E	4500-Cl E-00					X
DPD Ferrous Titrimetric	4500-Cl F	4500-Cl F-00			X	X	X
DPD Colorimetric	4500-Cl G	4500-Cl G-00			X	X	X
Syringaldazine (FACTS)	4500-Cl H	4500-Cl H-00			X
Iodometric Electrode	4500-Cl I	4500-Cl I-00					X
DPD	4500-ClO2 D							X
Amperometric Method II	4500-ClO2 E	4500-ClO2 E-00						X
Lissamine Green Spectrophotometric				327.0 Rev 1.1				X
1 X indicates method is approved for measuring specified disinfectant residual. Free chlorine or total chlorine may be measured for demonstrating compliance with the chlorine MRDL and combined chlorine, or total chlorine may be measured for demonstrating compliance with the chloramine MRDL.
2 The Standard Methods Online version that is approved is indicated by the last two digits in the method number which is the year of approval by the Standard Method Committee. Standard Methods Online are available at http://www.standardmethods.org.