&EPA
United States
Environmental Protection
Agency
                        The Third Unregulated Contaminant Monitoring Rule  (UCMR 3)
                                      Fact Sheet for Assessment Monitoring (List 1 Contaminants)
Overview of the Rule
*> Title: Revisions to the Unregulated Contaminant Monitoring Rule for Public Water Systems; 77 FR 26072, May 2,2012.
*> Purpose: To collect occurrence data for contaminants suspected to be present in drinking water but that do not have health-based
  standards set under the Safe Drinking Water Act (SDWA). Assessment Monitoring targets contaminants that are analyzed with methods
  that utilize existing and widely used technology. The UCMR program is the primary source of drinking water contaminant occurrence data
  used by EPA in regulatory determinations.
*> Description: UCMR 3 includes Assessment Monitoring for 21 List 1 chemical contaminants using six EPA-approved analytical methods and
  four equivalent consensus methods. List 1 contaminants are always associated with an Assessment Monitoring sampling design. Public
  water systems (PWSs) subject to Assessment Monitoring will sample within a 12-month period during 2013 - 2015.
«J« Utilities Affected:  Community water systems (CWSs) and non-transient non-community water systems (NTNCWSs) with more than 10,000
  retail customers and a representative sample of 800 systems serving 10,000 or fewer retail customers are required to conduct Assessment
  Monitoring.
«J« Occurrence Data: The analytical results from UCMR 3 are stored in the National Contaminant Occurrence Database (NCOD). For a
  summary of the NCOD results, tips for querying NCOD, and health effects information (including reference concentrations) please refer to
  the UCMR 3 Data Summary document.

Assessment Monitoring (List 1  Contaminants)
iwipl 2
Contaminant/ CASRN1 . ... Use or Environmental Source3
Volatile Organic Compounds: EPA Method 524.3
1,2,3-trichloropropane
96-18-4
1,3-butadiene
106-99-0
chloromethane (methyl
chloride)
74-87-3
1,1-dichloroethane
75-34-3
0.03
0.1
0.2
0.03
Halogenated alkane; used as an ingredient in paint, varnish remover, solvents and
agents
degreasing
Alkene; used in rubber manufacturing and occurs as a gas
Halogenated alkane; used as foaming agent, in production of other substances, and by-
product that can form when chlorine used to disinfect drinking water
Halogenated alkane; used as a solvent
bromomethane Halogenated alkane; occurs as a gas, and used as a fumigant on soil before plantin
74-83-9 after harvest, on vehicles and buildings, and for other specialized purposes
chlorodifluoromethane
(HCFC-22)
75-45-6
bromochloromethane
(Halon 1011)
74-97-5
0.08
0.06
g, on crops
Chlorofluorocarbon; occurs as a gas, and used as a refrigerant, as a low-temperature solvent,
and in fluorocarbon resins, especially tetrafluoroethylene polymers
Used as a fire-extinguishing fluid, an explosive suppressant, and as a solvent in the
manufacturing of pesticides
Office of Water (MS-140)
                      EPA 815-F-16-003
May 2016

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Synthetic Organic Compound: EPA Method 522
1,4-dioxane
123-91-1
0.07
Cyclic aliphatic ether; used as a solvent or solvent stabilizer in manufacture and processing of
paper, cotton, textile products, automotive coolant, cosmetics and shampoos
Metals: EPA Method 200.8; SM 3125; ASTM D5763-104
vanadium Naturally-occurring elemental metal; used as vanadium pentoxide which is a chemical
7440-62-2 ' intermediate and a catalyst
molybdenum
7439-98-7
cobalt
7440-48-4
strontium
7440-24-6
chromium5
CASRN n/a
1
1
0.3
0.2
Naturally-occurring element found in ores and present in plants, animals and bacteria;
commonly used form molybdenum trioxide used as a chemical reagent
Naturally-occurring element found in the earth's crust and at low concentrations in seawater,
and in some surface and ground water; cobaltous chloride was formerly used in medicine and
as a germicide
Naturally-occurring element; historically, commercial use of strontium has been in the
faceplate glass of cathode-ray tube televisions to block x-ray emissions
See chromium-6 for use or source information; though the amount measured when analyzing
for "total chromium" is the sum of chromium in all of its valence states, the MCL for EPA's
current total chromium regulation was determined based upon the health effects of
chromium-6
Chromium-6: EPA Method 218.7
chromium-66
18540-29-9
0.03
Naturally-occurring element; used in making steel and other alloys; chromium-3 or -6 forms
are used for chrome plating, dyes and pigments, leather tanning, and wood preservation
Oxyhalide Anion: EPA Method 300.1; SM 4110D; ASTM D658-08
chlorate Agricultural defoliant or desiccant; disinfection byproduct; and used in production of chlorine
14866-68-3 dioxide
Perfluorinated Compounds: EPA Method 537
perfluorooctanesulfonic Surfactant or emulsifier; used in fire-fighting foam, circuit board etching acids, alkaline
acid (PFOS) 0.04 cleaners, floor polish, and as a pesticide active ingredient for insect bait traps; U.S.
1763-23-1 manufacture of PFOS phased out in 2002; however, PFOS still generated incidentally
perfluorooctanoic acid
(PFOA)
335-67-1
perfluorononanoic acid
(PFNA)
375-95-1
perfluorohexanesulfonic
acid (PFHxS)
355-46-4
perfluoroheptanoic acid
(PFHpA)
375-85-9
0.02
0.02
0.03
0.01
Perfluorinated aliphatic carboxylic acid; used for its emulsifier and surfactant properties in or
as fluoropolymers (such as Teflon), fire-fighting foams, cleaners, cosmetics, greases and
lubricants, paints, polishes, adhesives and photographic films
Manmade chemical; used in products to make them stain, grease, heat and water resistant
Manmade chemical; used in products to make them stain, grease, heat and water resistant
Manmade chemical; used in products to make them stain, grease, heat and water resistant
perfluorobutanesulfonic
acid (PFBS) 0.09 Manmade chemical; used in products to make them stain, grease, heat and water resistant
375-73-5 |
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1. CASRN - Chemical Abstracts Service Registry Number
2. MRL- Minimum Reporting Level
3. "Use or Environmental Source" further documented in UCMR 3 Contaminants - Information Compendium. EPA 81B-B-11-001. January 2012
4. SM-Standard Methods; ASTM-ASTM International
5. Monitoring for total chromium, in conjunction with UCMR 3 Assessment Monitoring, is required under the authority provided in Section 144B(a)(l)(A) of SDWA
6. Chromium-6 will be measured as soluble chromate ion (CASRN 13907-45-4)
Assessment Monitoring
   Time frame: One consecutive 12-month period during January 2013 - December 2015 (monitoring can span more than one calendar year,
   as long as conducted during a consecutive 12-month period).
   Frequency: Ground Water. Monitoring will occur twice in one consecutive 12-month period. Sample events must occur 5 - 7 months apart.
   Surface Water or GUDI: Monitoring will occur in 4 consecutive quarters, with sampling events occurring 3 months apart.
   Location: Entry point to the distribution system (EPTDS) for all contaminants, as well as distribution system maximum residence time
   sampling locations for chromium, chromium-6, cobalt, molybdenum, strontium, vanadium and chlorate.
   Laboratories: Samples must be analyzed by EPA-approved laboratories.
Critical Deadlines and Requirements
Due Date

rtrtrthAi- 1 9fi1 9

August 1, 2012
October 1, 2012


Within 120 days
of sample
collection
Within 60 days
of lab posting
data
Requirement
Following Rule Publication
Systems must submit contact information to SDWARS. (Any subsequent
changes must be submitted within 30 days of the change occurring).
Laboratories seeking approval must submit a registration form to
participate in the laboratory approval process.
Ground water systems that wish to monitor from representative EPTDSs
must submit either state-approved, UCMR 2-approved or propose a new
representative sampling plan.
Deadline for systems to change their monitoring schedule (after October
1, systems must provide an explanation for the requested schedule
change and obtain EPA approval of the change).
PWSs review/edit if necessary, inventory information for sampling
locations.
Following Sample Collection
Laboratories post data to SDWARS.
PWSs review and approve the data. If the PWS has not taken action after
60 days, the data are considered approved and ready for state and EPA
review.
Report
through
SDWARS1

X


X
X

X
X
Contact
Sampling
Coordinator2


X
X
X (after
October 1)
X (after
October 1)



1. Safe Drinking Water Accession and Review System
2. Contact via email at: UCMR Sampling Coordinator@epa.gov.

Data Elements
Public Water System
Identification (PWSID)
Code
Public Water System
Facility Identification
Code
Water Source Type
Sampling Point
Identification Code
Sampling Point Type
Code
Disinfectant Type
Sample Collection Date
Sample Identification
Code
Contaminant
Analytical Method Code
Sample Analysis Type
Analytical Results-Sign
Analytical
Result-Value
Laboratory
Identification Code
Sample Event Code
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Additional Information
  The Public Notification Rule (40 CFR §141.207), published on May 4, 2000 (65 FR 25982) with amendments and corrections
  included in the Code of Federal Regulations for the Public Notification Rule published on July 1, 2006, requires PWSs to notify the
  public annually that the results of monitoring for unregulated contaminants are available. CWSs may include their public notice
  within their CCRs. Details on these reporting requirements can be found in the document: Revised Public Notification Handbook
  (EPA816-R-09-013).
  Under the Consumer Confidence Report (CCR) Rule, as specified in 40 CFR§141.153(d), CWSs must report the monitoring
  results whenever unregulated contaminants are detected. CCRs are delivered to all billing customers each year by July 1. (The
  CCR Rule does not apply to non-community water systems). Details on these reporting requirements can be found on the CCR
  Home Page.
  For More Information
     * Safe Drinking Water Hotline: (800) 426-4791
     * CDX/SDWARS Help Desk: (888) 890 -1995
     * UCMR Homepage
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