## Announcement of Final Rule: Unregulated Contaminant Monitoring Rule (UCMR 3) for Public Water Systems

Summary Under the third Unregulated Contaminant Monitoring Rule (UCMR 3), large public water systems (PWSs) and a representative sample of small PWSs will monitor for 28 chemical contaminants and two viruses from January 2013 through December 2015. UCMR 3 will provide EPA and other interested parties with scientifically valid data on the occurrence of these contaminants in drinking water, permitting the assessment of the number of people potentially being exposed and the levels of that exposure. The data represent one of the primary sources of occurrence and exposure information the Agency uses to develop regulatory decisions for these emerging contaminants. Background Section 1445(a)(2) of the 1996 Safe Drinking Water Act (SDWA) amendments requires that once every five years, EPA issue a new list of no more than 30 unregulated contaminants to be monitored by public water systems (PWSs). The first Unregulated Contaminant Monitoring Regulation (UCMR 1) was published on September 17, 1999, and the second (UCMR 2) was published on January 4, 2007. This monitoring provides a basis for future regulatory actions to protect public health. The UCMR 3 proposed rule was published in the Federal Register on March 3, 2011. About this regulation UCMR monitoring helps the Agency understand contaminant occurrence in drinking water and supports determinations as to whether particular contaminants need to be regulated. This final rule requires PWSs to monitor for the 28 chemical contaminants and two viruses shown in Exhibit 1. UCMR 3 samples will be collected at entry points to the distribution system (EPTDSs). Additionally, monitoring for total chromium, chromium-6, cobalt, molybdenum, strontium, vanadium, and chlorate will also take place at the distribution system maximum residence time (DSMRT) location. PWSs may perform sampling at representative ground water sampling locations and representative intakes from wholesalers. Sampling frequency will depend on the PWS water type. PWSs with surface water or “ground water under the direct influence of surface water” will monitor four times (quarterly) during their applicable year of monitoring. PWSs with ground water will monitor twice (five to seven months apart) during their applicable year of monitoring. PWSs can adjust the monitoring schedule initially established by EPA.

EPA 815-R-12-001 Page 1 of 5 April 2012Exhibit 1: UCMR 3 Final Contaminant Lists List 1, Assessment Monitoring 1,4-dioxane vanadium molybdenum strontium
cobalt chromium-6 (hexavalent chromium) 1 1,2,3-trichloropropane total chromium 2
chlorate perfluorooctanesulfonic acid (PFOS) 1,3-butadiene perfluorooctanoic acid (PFOA) chloromethane (methyl chloride) perfluorononanoic acid (PFNA) 1,1-dichloroethane perfluorohexanesulfonic acid (PFHxS) bromochloromethane (Halon 1011) perfluoroheptanoic acid (PFHpA) bromomethane (methyl bromide) perfluorobutanesulfonic acid (PFBS) chlorodifluoromethane (HCFC-22) List 2, Screening Survey 17-β-estradiol estriol 17-α-ethynylestradiol (ethinyl estradiol) equilin
estrone testosterone 4-androstene-3,17-dione List 3, Pre-Screen Testing 3
enteroviruses noroviruses 1. Chromium-6 will be measured as soluble chromate (ion). 2. Monitoring for total chromium – in conjunction with UCMR 3 Assessment Monitoring – is required under the authority provided in Section 1445(a)(1)(A) of SDWA. 3. EPA will collect the samples from List 3 sampling locations, and will pay for all sampling and analysis costs associated with virus and indicator monitoring at these small systems.

EPA 815-R-12-001 Page 2 of 5 April 2012EPA generally divides unregulated contaminant monitoring into three types of monitoring, or “lists”. UCMR 3 includes monitoring under each of the three lists, as follows:

 Assessment Monitoring (List 1): All PWSs serving more than 10,000 people (i.e., large systems) and 800 representative PWSs serving 10,000 or fewer people (i.e., small systems) will monitor for 21 chemicals contaminants.

 Screening Survey (List 2): All PWSs serving more than 100,000 people, a representative sample of 320 large PWSs serving 10,001 to 100,000 people, and a representative sample of 480 small PWSs serving 10,000 or fewer people will monitor for seven chemicals contaminants.

 Pre-Screen Testing (List 3): Two viruses and related pathogen indicators (i.e., total coliforms, E. coli , bacteriophage, Enterococci , and aerobic spores) will be monitored at a representative selection of 800 undisinfected ground water PWSs serving 1,000 or fewer people. The virus monitoring will take place in sensitive hydrogeological areas (e.g., karst or fractured bedrock). Consistent with UCMR 1 and UCMR 2, EPA will manage and fund the UCMR 3 monitoring at small systems. All laboratories conducting analyses for UCMR 3 List 1 and List 2 contaminants must receive EPA approval to perform those analyses (see “UCMR 3 Laboratory Approval Requirements and Information Document” for details of EPA’s UCMR laboratory approval program). Pre-Screen Testing (List 3) analyses for viruses and indicators are organized and paid for by EPA through direct contracts with microbiology laboratories. The List 3 laboratories are subject to a laboratory approval process as part of their direct contracts with EPA. What are the major differences between the UCMR 3 proposed rule and final rule? Key revisions, relative to the March 2011 proposed rule, are as follows:

 Chromium-6 and total chromium were added to the final contaminants list;

 Sec -butylbenzene and n -propylbenzene were removed from the final contaminants list;

 Monitoring of hormones was moved from Assessment Monitoring (List 1) to Screening Survey (List 2);

 PWSs are required to report zip codes only for the customers they serve (zip codes associated with each sampling point will not be required);

 The laboratory reporting timeframe is now 120 days after sample collection (same as earlier UCMRs); and

 The PWS reporting timeframe is now 60 days after laboratories post data (same as earlier UCMRs).

EPA 815-R-12-001 Page 3 of 5 April 2012How did EPA select these contaminants? EPA selected the contaminants that will be monitored through a process that included a review of EPA's Contaminant Candidate List, which highlights priority contaminants that need additional research to support future drinking water regulations. The contaminants on the list are known or anticipated to occur in public water systems but are not addressed by existing national drinking water regulations. Additional contaminants of concern were selected based on current occurrence research and health-risk factors. What are the major differences between UCMR 2 and 3? This proposed rule (UCMR 3) revises the previous rule (UCMR 2) as follows: it updates the list of contaminants to be monitored; it provides information on how many systems will be required to monitor and where they are required to monitor (typically just after treatment and, in the case of several contaminants, in the distribution system); it identifies the analytical methods to be used; and it makes minor modifications to the requirements based on our experience implementing UCMR 1 and UCMR 2. What is the cost of the regulation? EPA estimates that nationwide, the average annual cost of UCMR 3, across the five-year cycle of 2012-2016, is approximately $17.45 million. The total estimated annual costs are described in Exhibit 2. The final rule applies to PWSs and the states. Non-labor costs will be incurred primarily by EPA and large PWSs. They include the cost of shipping samples to laboratories and the cost of the actual laboratory analyses. Labor costs pertain to PWSs, states and EPA. These costs include activities such as reading the regulation, notifying PWSs selected to participate, collecting samples, reviewing data, reporting, and keeping records. EPA expects that states will incur only labor costs associated with voluntary assistance with UCMR 3 implementation. Since state participation will be voluntary, level of effort will vary depending on their individual agreements with EPA. The average annual costs for small water systems complying with this rule are minimal. EPA specifically structured the rule to avoid significantly affecting small entities by funding all costs for laboratory analyses, shipping, and quality control for small entities. Small systems monitoring for chemicals will only incur labor costs, which are attributed to the labor required for reading about their requirements and collecting samples. Small systems participating in virus monitoring will incur even lower labor costs since EPA contractors will collect the samples, record and report the data (because of the complexity of the sampling techniques).

EPA 815-R-12-001 Page 4 of 5 April 2012EPA 815-R-12-001 Page 5 of 5 April 2012 Exhibit 2: National Estimate d Annual Cost of UCMR 3 (2012-2016) Avg. Annual Respondent Cost. All Respondents (2012-2016) Small Systems (25-10,000), including labor only, non-labor costs paid for by $0.066 m EPA Large Systems (10,001-100,000), including labor and non-labor costs $9.55 m V ery Large Systems (100,001 and greater), including labor and non-labor $2.94 m costs States, including labor costs related to implementation coordination $0.75 m EPA, including labor for implementation, non-labor for small system testing $4.14 m AVERAGE ANNUAL NATIONAL TOTAL $17.45 m

How can I get additional information? For further information on UCMR 3, please visit the UCMR 3 website at: http://water.epa.gov/lawsregs/rul esregs/sdwa/ucm r/ucmr3/index.cfm

. You may also contact the Safe Dri nking Water Hotline at (800) 426-4791 or http://water.epa.gov/drink/contact.cfm

.