Chemical Waivers

Chemical Waivers

The purpose of monitoring waivers for inorganic and organic chemicals is to decrease costs for a Public Water System (PWS) while still providing safe drinking water to the public.

The United States Environmental Protection Agency (EPA) has authorized states to issue reduced monitoring waivers for inorganic and organic chemicals to PWSs that have completed an approved waiver application and review process. The Montana Department of Environmental Quality (DEQ) allows decreased monitoring of specific inorganics (IOC and asbestos) and organic (SOC and VOC) chemicals.

Chemical waivers occur at both the area-wide level and the individual PWS level. Statewide waivers are area-wide waivers that cover Montana and are applied to all PWSs within state jurisdiction. For individual PWS waivers, an asbestos waiver is available for the distribution system, whereas, all other analytes are available at the entry point. The PWS must apply for and comply with the waiver requirements.


Statewide waivers are automatically applied to all Community (C) and Non-transient Non-community (NTNC) PWSs that are regulated by DEQ.

All C and NTNC PWS are eligible to apply for individual PWS chemical waivers. (1) Transient Non-community PWS are not eligible for chemical waivers as they are not required to monitor for chemicals. PWS with groundwater, surface water and groundwater under direct influence of surface water (GWUDISW) are eligible (2). GWUDISW, groundwater and surface water sources mixed before distribution, and surface-water-only sources are all considered surface water sources for chemical waivers.(3)

In total, 56 chemicals are available for a reduced monitoring waiver, including Inorganic Chemicals (IOC), Synthetic Organic Chemicals (SOC), and Volatile Organic Chemicals (VOC). Analytes that are not available for a waiver include, but are not limited to nitrate, nitrite, lead, copper, total trihalomethanes, haloacetic acids, and radionuclides. Waivers are granted on a contaminant-by-contaminant basis.

Monitoring Schedule

The table below is a modified Standardized Monitoring Framework provided by the EPA that summarizes PWS responsibility for specific waivers. This monitoring schedule is determined on a nine-year compliance cycle that is divided into three compliance periods consisting of three-year monitoring periods. Some waivers reduce monitoring frequency, while other waivers eliminate monitoring during a specific schedule. Waivers do require a once per nine-year monitoring which has to be completed in the first three years of the new monitoring period. Public notice must be posted in each of the monitoring periods for which the waiver is valid.

Table 1. Summary of Waiver Requirements

Chemical Waiver Table

Shading indicates years a waiver is in effect. No shading indicates the PWS does not have a waiver. *A SOC waiver only lasts 3 years (1 compliance period). **A VOC waiver only lasts 6 years (two compliance periods). PN = Public Notice; VA = Vulnerability Assessment; The samples for IOC, SOC and VOC are per entry point.

Individual Waiver Application Evaluation

Public water supply owners need to submit in writing a request for a monitoring waiver to the DEQ Chemical Rule Manager to be eligible for waivers. Verbal waivers are not acceptable and will not be considered. Monitoring waivers may decrease a public water system’s sampling frequency for specific contaminant groups. Renewal of waivers require an application to be completed and submitted, this application can be found at:

Monitoring waivers are based on specific monitoring schedules established in the Standardized Monitoring Framework under Phase II, IIB & V federal rules as shown in Table 1. Monitoring waivers allow public water supply systems to reduce sampling frequencies by three, six, or nine years.


Diane Jordan
Chemical/Radiological/ Waiver Rule Manager
PO Box 200901
Helena, MT 59620
Phone: (406) 444-6741
Fax: (406) 444-1374
DEQ: (406) 444-4400


1: 40 CFR 141.23 (c) (2); 40 CFR 141.24(f)(7); 40 CFR 141.24(h)(5); 40 CFR 141.23 (b) (2)
2: 40 CFR 141.24(h)(5) SOC
3: 40 CFR 141.23 (a)(2); 40 CFR 141.23 (c)(1); 40 CFR 141.24(h)(2)