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  2. Monitoring Unregulated Drinking Water Contaminants

Reporting Requirements for the Fifth Unregulated Contaminant Monitoring Rule (UCMR 5)

Large and small public water systems (PWSs) subject to UCMR 5 (i.e., community water systems (CWSs) and non-transient non-community water systems (NTNCWSs)) are required to take action in EPA’s web-based reporting system, the “Safe Drinking Water Accession and Review System” (or “SDWARS 5”). Laboratories responsible for sample analysis submit data to SDWARS 5 on behalf of PWSs, consistent with prior UCMR cycles. Users (including PWSs that wish to review/approve data submitted by their laboratories) access SDWARS through EPA’s Central Data Exchange (CDX). SDWARS 5 demos for large and small PWSs, and states are available to walk users through how to complete these actions.

  • SDWARS 5 Walkthrough – Large PWS serving more than 10,000 people (video)
  • SDWARS 5 Walkthrough – Small PWS serving 10,000 or fewer people (video)
  • SDWARS 5 Walkthrough - State (video)
  • CDX

PWSs that are subject to UCMR 5 are also subject to the Consumer Confidence Report (CCR) and the Public Notification (PN) rules. The CCR rule requires that community water systems (CWSs) report monitoring results when unregulated contaminants are measured at or above the UCMR 5 minimum reporting level (40 CFR 141.153). CWSs must report the average and range of the year’s monitoring results. Consumers interested in their CCR should contact their water supplier or may find information on how to obtain a copy of the CCR in their water bill. The PN rule requires that PWSs notify their customers that the UCMR results are available (40 CFR 141.207) no later than 12 months after they are known. Many CWSs meet these PN requirements using their CCR, which is to be delivered to all billing customers each year by July 1 (40 CFR 141.204[d]). Please refer to the CCR rule and the PN rule for further information.

  • PWS Types
On this page:
  • Key reporting dates
  • Questions and answers on reporting
  • Data elements for UCMR 5

Key reporting dates

Deadlines for UCMR 5 reporting

Six months prior to scheduled sample collection:

  • Ground water PWSs serving more than 10,000 people that wish to monitor from representative entry points to the distribution system (EPTDS), using the flexibility described in the rule, must submit either:
    • a copy of an approved ground water representative monitoring plan (GWRMP) from a prior UCMR cycle, or
    • a new, proposed GWRMP
  • Changes to inventory data in SDWARS that impact a PWS’s representative plan must be reported within 30 days of the change

Before December 31, 2022:

  • PWSs were required to establish a CDX/SDWARS account and take the following actions:
    • Read and accept their UCMR 5 Notification Letter
    • Review and, as needed, adjust sample location inventory
    • Add the zip codes associated with all customers in their service area
    • Review their sampling schedule
    • Provide a physical shipping address (applicable for PWSs serving 10,000 or fewer people)

After December 31, 2022:

  • PWSs serving more than 10,000 people are required to notify EPA:
    • of sampling location and inventory changes
    • if unable to sample according to the original schedule

Deadlines for reporting UCMR 5 monitoring results

  • Within 90 days of sample collection: Laboratories must submit monitoring results to EPA's web-based reporting system, SDWARS.
  • Within 30 days of lab submitting data: PWSs serving more than 10,000 people may review and approve data; if no action is taken within this review period, results for large PWSs are treated as approved and ready for EPA/state review.

Questions and answers on reporting

What do public water systems serving 10,000 or fewer people ("small PWSs") need to do?

EPA arranges and pays for sample analysis, and reviews monitoring results for small PWSs. After review, EPA releases data to the small PWSs and states through SDWARS. UCMR 5 data reside on UCMR's Occurrence Data page in EPA's National Contaminant Occurrence Database (NCOD).

Small PWSs notified by EPA that they are subject to UCMR 5 participation need to do the following:

  • Establish a CDX/SDWARS account and take the following actions:
    • Read and accept their UCMR 5 Notification Letter
    • Review and, as needed, adjust sample location inventory
    • Add the zip codes associated with all customers in their service area
    • Review their sampling schedule
    • Provide a physical shipping address
    • Select responses to the UCMR 5 Data Elements (e.g., Disinfectant Type)
  • Collect samples for UCMR 5 contaminants, using sampling kits and following sampling instructions provided by the Agency's support contractor, Great Lakes Environmental Center (GLEC).
  • Save the SDWARS report as their official record.

What do public water systems serving more than 10,000 people ("large PWSs") need to do?

Large PWSs subject to UCMR 5 need to do the following:

  • Establish a CDX/SDWARS account to take the following actions:
    • Read and accept their UCMR 5 Notification Letter
    • Review and, as needed, adjust sample location inventory
    • Add the zip codes associated with all customers in their service area
    • Review their sampling schedule
    • Select responses to the UCMR 5 Data Elements (e.g., Disinfectant Type)
  • Collect samples for unregulated contaminants per the established schedule
  • Contract with laboratories approved by EPA for analysis of their UCMR 5 samples

In addition, large PWSs will have 30 days after their laboratory submits data to SDWARS to review and approve their analytical results. If the PWS does not act on their data within those 30 days, EPA will consider the data approved by the PWS and available to EPA and states for review and public release. After review, UCMR 5 data reside on UCMR's Occurrence Data page in EPA's National Contaminant Occurrence Database (NCOD).

What do laboratories need to do?

Laboratories granted EPA approval are obligated to report their data to SDWARS within 90 days of sample collection. Laboratories can only submit data for methods, for which they have received EPA approval. Instructions on submitting data can be found in SDWARS.

What do states need to do?

States will have an opportunity to review PWS data in SDWARS upon:

  • PWS approval for results from large PWSs, and
  • EPA review/approval for results from small PWSs

Data elements for UCMR 5

Data element

Definition

1. Public Water System Identification (PWSID) Code

The code used to identify each PWS. The code begins with the standard 2-character postal State abbreviation or Region code; the remaining 7 numbers are unique to each PWS in the State. The same identification code must be used to represent the PWS identification for all current and future UCMR monitoring.

2. Public Water System Name

Name of the PWS.

3. Public Water System Facility Identification Code

Identification code for each applicable facility associated with water treatment or delivery at the PWS.

4. Public Water System Facility Name

Name of the facility at the PWS.

5. Public Water System Facility Type

That code that identifies that type of facility as either:
CC = Consecutive connection.
SS = Sampling station.
TP = Treatment plant.
OT = Other.

6. Water Source Type

The type of source water that supplies a water system facility. Systems must report one of the following codes for each sampling location:
SW = Surface water (to be reported for water facilities that are served entirely by a surface water source during the 12-month period).
GU = Ground water under the direct influence of surface water (to be reported for water facilities that are served all or in part by ground water under the direct influence of surface water at any time during the 12-month sampling period), and are not served at all by surface water during this period.
MX = Mixed water (to be reported for water facilities that are served by a mix of surface water, ground water, and/or ground water under the direct influence of surface water during the 12-month period).
GW = Ground water (to be reported for water facilities that are served entirely by a ground water source during the 12-month period).

7. Sampling Point Identification Code

Identification code for each sample point location at a PWS.

8. Sampling Point Name

Name of the sample point name at the PWS.

9. Sampling Point Type Code

A code that identifies the location of the sampling point as:
EP = Entry point to the distribution system.

10. Disinfectant Type

All of the disinfectants/oxidants that have been added prior to the entry point to the distribution system. Please select all that apply.
PEMB = Permanganate.
HPXB = Hydrogen peroxide.
CLGA = Gaseous chlorine.
CLOF = Offsite generated hypochlorite (stored as a liquid form).
CLON = Onsite generated hypochlorite.
CAGC = Chloramine (formed with gaseous chlorine).
CAOF = Chloramine (formed with offsite hypochlorite).
CAON = Chloramine (formed with onsite hypochlorite).
CLDB = Chlorine dioxide.
OZON = Ozone.
ULVL = Ultraviolet light.
OTHD = All other types of disinfectant/oxidant.
NODU = No disinfectant/oxidant used.

11. Treatment Information

Treatment information associated with the sample point. Please select all that apply.
CON = Conventional (non-softening, consisting of at least coagulation/sedimentation basins and filtration)
SFN = Softening
RBF = River bank filtration
PSD = Pre-sedimentation
INF = In-line filtration
DFL = Direct filtration
SSF = Slow sand filtration
BIO = Biological filtration (operated with an intention of maintaining biological activity within filter)
UTR = Unfiltered treatment for surface water source
GWD = Groundwater system with disinfection only
PAC = Application of powder activated carbon
GAC = Granular activated carbon adsorption (not part of filters in CON, SFN, INF, DFL, or SSF)
AIR = Air stripping (packed towers, diffused gas contactors)
POB = Pre-oxidation with chlorine (applied before coagulation for CON or SFN plants or before filtration for other filtration plants)
MFL = Membrane filtration
IEX = Ionic exchange
DAF = Dissolved air floatation
CWL = Clear well/finished water storage without aeration
CWA = Clear well/finished water storage with aeration
ADS = Aeration in distribution system (localized treatment)
OTH = All other types of treatment
NTU = No treatment used
DKN = Do not know

12. Sample Collection Date

The date the sample is collected, reported as month, day, and year (MM/DD/YYYY).

13. Sample Identification Code

Identification code for each sample.

14. Contaminant

The UCMR 5 contaminant analyzed.

15. Analytical Method Code

The identification code of the analytical method used.

16. Extraction Batch Identification Code

Laboratory assigned extraction batch ID. Must be unique for each extraction batch within the laboratory for each method. For CCC samples report the Analysis Batch Identification Code as the value for this field. For methods without an extraction batch, leave this field null.

17. Extraction Date

Date for the start of the extraction batch (YYYY/MM/DD). For methods without an extraction batch, leave this field null.

18. Analysis Batch Identification Code

Laboratory assigned analysis batch ID. Must be unique for each analysis batch within the laboratory for each method.

19. Analysis Date

Date for the start of the analysis batch (YYYY/MM/DD).

20. Sample Analysis Type

The type of sample collected and/or prepared, as well as the fortification level. Permitted values include:
CCCL = MRL level continuing calibration check; a calibration standard containing the contaminant, the internal standard, and surrogate analyzed to verify the existing calibration for those contaminants.
CCCM = Medium level continuing calibration check; a calibration standard containing the contaminant, the internal standard, and surrogate analyzed to verify the existing calibration for those contaminants. 
CCCH = High level continuing calibration check; a calibration standard containing the contaminant, the internal standard, and surrogate analyzed to verify the existing calibration for those contaminants.
FS = Field sample; sample collected and submitted for analysis under this final rule.
LFB = Laboratory fortified blank; an aliquot of reagent water fortified with known quantities of the contaminants and all preservation compounds.
LRB = Laboratory reagent blank; an aliquot of reagent water treated exactly as a field sample, including the addition of preservatives, internal standards, and surrogates to determine if interferences are present in the laboratory, reagents, or other equipment.
LFSM = Laboratory fortified sample matrix; a UCMR field sample with a known amount of the contaminant of interest and all preservation compounds added.
LFSMD = Laboratory fortified sample matrix duplicate; duplicate of the laboratory fortified sample matrix.
QCS = Quality control sample; a sample prepared with a source external to the one used for initial calibration and CCC. The QCS is used to check calibration standard integrity.
FRB = Field reagent blank; an aliquot of reagent water treated as a sample including exposure to sampling conditions to determine if interferences or contamination are present from sample collection through analysis.

21. Analytical Result—Sign

A value indicating whether the sample analysis result was:
(<) “less than” the Minimum Reporting Level.
(=) “equal to” a numeric value at or above the Minimum Reporting Level and reported in “Analytical Result— Measured Value.”

22. Analytical Result—Measured Value

The actual numeric value of the analytical results for: field samples; laboratory fortified matrix samples; laboratory fortified sample matrix duplicates; and concentration fortified.

23. Additional Value

Represents the true value or the fortified concentration for spiked samples for QC Sample Analysis Types (CCCL, CCCM, CCCH, QCS, LFB, LFSM, and LFSMD).

24. Laboratory Identification Code

The code, assigned by EPA, used to identify each laboratory. The code begins with the standard two-character State postal abbreviation; the remaining five numbers are unique to each laboratory in the State.

25. Sample Event Code

A code for each sample event.
SE1, SE2, SE3 and SE4 - Represent samples collected to meet UCMR Assessment Monitoring requirements; where “SE1” and “SE2” represent the first and second sampling period for all water types; and “SE3” and “SE4” represent the third and fourth sampling period for SW, GU, and MX sources only.
26. Historical Information for Contaminant Detections and Treatment A yes or no answer provided by the PWS for each entry point to the distribution system. 
Question: Have you tested for the contaminant in your drinking water in the past?
YES = If yes, did you modify your treatment and if so, what types of treatment did you implement? Select all that apply.
  • PAC = Application of powder activated carbon
  • GAC = Granular activated carbon adsorption (not part of filters in CON, SFN, INF, DFL, or SSF)
  • IEX = Ionic exchange
  • NRO = Nanofiltration and reverse osmosis
  • OZN = Ozone
  • BAC = Biologically active carbon
  • MFL = Membrane filtration
  • UVL = Ultraviolet light
  • OTH = Other
  • NMT = Not modified after testing
NO = Never tested for the contaminant
DK = Do not know
27. Potential PFAS Sources A yes or no answer provided by the PWS for each entry point to the distribution system. 
Question: Are you aware of any potential current and/or historical sources of PFAS that may have impacted the drinking water sources at your water system? 
YES = If yes, select all that apply:
  • MB = Military base 
  • FT = Firefighting training school
  • AO = Airport operations
  • CW = Car wash or industrial launderers
  • PS = Public safety activities (e.g., fire and rescue services)
  • WM = Waste management
  • HW = Hazardous waste collection, treatment and disposal
  • UW = Underground Injection Well
  • SC = Solid waste collection, combustors, incinerators
  • MF = Manufacturing
  • FP = Food packaging
  • TA = Textile and apparel (e.g., stain- and water- resistant, fiber/thread, carpet, house furnishings, leather)
  • PP = Paper
  • CC = Chemical
  • PR = Plastics and rubber products
  • MM = Machinery
  • CE = Computer and electronic products
  • FM = Fabricated metal products (e.g., nonstick cookware)
  • PC = Petroleum and coal products
  • FF = Furniture
  • OG = Oil and gas production
  • UT = Utilities (e.g., sewage treatment facilities) 
  • CT = Construction (e.g., wood floor finishing, electrostatic painting)
  • OT = Other
NO = Not aware of any potential current and/or historical sources
DK = Do not know

Monitoring Unregulated Drinking Water Contaminants

  • About the Unregulated Contaminant Monitoring Rule (UCMR)
  • Meetings & Materials
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    • UCMR 5 Data Finder
  • Reporting Requirements
  • UCMR 5
Contact Us About Monitoring Unregulated Drinking Water Contaminants
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on September 1, 2024
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