Nebraska Administrative Code
Topic - HEALTH AND HUMAN SERVICES SYSTEM
Title 179 - PUBLIC WATER SYSTEMS
Chapter 16 - DISINFECTANTS AND DISINFECTION BYPRODUCTS
Section 179-16-004 - ANALYTICAL REQUIREMENTS
Current through September 17, 2024
004.01 General
Disinfection Byproduct |
Acceptance limits (percent of true value) |
Comments |
TTHM Chloroform Bromodichloromethane Dibromochloromethane Bromoform |
±20 ±20 ±20 ±20 |
Laboratory must meet all 4 individual THM acceptance limits in order to successfully pass a PE sample for TTHMs |
HAA5 Monochloroacetic Acid Dichloroacetic Acid Trichloroacetic Acid Monobromoacetic Acid Dibromoacetic Acid |
+40 +40 +40 +40 +40 |
Laboratory must meet the acceptance limits for 4 out of 5 of the HAA5 compounds in order to successfully pass a PE sample for HAA5 |
Chlorite |
±30 |
|
Bromate |
+30 |
Disinfection Byproduct |
Minimum reporting level (mg/L) 1 |
Comments |
TTHM 2 Chloroform Bromodichloromethane Dibromochloromethane Bromoform |
0.0010 0.0010 0.0010 0.0010 |
|
HAA5 2 Monochloroacetic Acid Dichloroacetic Acid Trichloroacetic Acid Monobromoacetic Acid Dibromoacetic Acid |
0.0020 0.0010 0.0010 0.0010 0.0010 |
|
Chlorite Bromate |
0.020 0.0050 or 0.0010 |
Applicable to monitoring as prescribed in 179 NAC 16-005.02 items 2.a(2) and 2.b. Laboratories that use EPA Methods 317.0 Revision 2.0, 326.0 or 321.8 must meet a 0.0010 mg/L MRL for bromate. |
1 The calibration curve must encompass the regulatory minimum reporting level (MRL) concentration. Data may be reported for concentrations lower than the regulatory MRL as long as the precision and accuracy criteria are met by analyzing an MRL check standard at the lowest reporting limit chosen by the laboratory. The laboratory must verify the accuracy of the calibration curve at the MRL concentration by analyzing an MRL check standard with a concentration less than or equal to 110% of the MRL with each batch of samples. The measured concentration for the MRL check standard must be ±50% of the expected value, if any field sample in the batch has a concentration less than 5 times the regulatory MRL. Method requirements to analyze higher concentration check standards and meet tighter acceptance criteria for them must be met in addition to the MRL check standard requirement.
2 When adding the individual trihalomethane or haloacetic acid concentrations to calculate the TTHM or HAA5 concentrations, respectively, a zero is used for any analytical result that is less than the MRL concentration for that DBP, unless otherwise specified by the Department.
004.03 Disinfectant Residuals
004.04 Additional Analytical Methods
: Systems required to analyze parameters not included in 179 NAC 16-004.02 and 16-004.03 must use the following methods or an equivalent method approved by EPA. The Department Laboratory (certified by EPA) or a laboratory that has entered into an agreement with the Department Laboratory must analyze for the following parameters, except that pH may be analyzed by the Department Laboratory, or a laboratory that has entered into an agreement with the Department Laboratory, or on-site by a Nebraska licensed Grade I, II, III, or IV operator or a person who has been trained on how to take the samples. If the sample is not taken by a licensed operator, Attachment 3 must be completed and sent to the Department.