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Monitoring Unregulated Drinking Water Contaminants

Reporting Requirements for the Unregulated Contaminant Monitoring Rule

Based on the UCMR 5 proposed rule, published March 11, 2021, laboratories responsible for sample analysis would post data to EPA’s web-based Safe Drinking Water Accession and Review System (SDWARS) on behalf of Public Water Systems (PWSs), consistent with prior UCMR cycles. Users (including PWSs that wish to review/approve data posted by their laboratories) access SDWARS through EPA’s Central Data Exchange (CDX).

PWSs that are subject to UCMR 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 detected (40 CFR 141.153). Consumers interested in their CCR report should contact their water supplier or may find information for how to obtain a copy of the CCR in their water bill. The PN rule requires that water systems notify the public that the results are available (40 CFR 141.207). Please refer to the CCR rule and the PN rule for further information.

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Key reporting dates

Proposed deadlines for reporting prior to sample collection

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
  • PWSs scheduled for sample collection in 2023 are encouraged to submit proposals for a new GWRMP by December 31, 2022
  • Changes to inventory data in SDWARS that impact a PWS’s representative plan must be reported within 30 days of the change

By December 31, 2022:

  • PWSs serving more than 10,000 people are required to report contact information to SDWARS
  • PWSs serving more than 10,000 people are required to review and, if necessary, revise:
    • sampling location information
    • monitoring schedule in SDWARS

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 established schedule

Proposed deadlines for reporting monitoring results

  • Within 90 days of sample collection: Laboratories post monitoring results to EPA's electronic reporting system, SDWARS.
  • Within 30 days of lab posting data: PWSs serving more than 10,000 people may review and approve data.

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Questions and answers on reporting

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

Under this proposal, all small public water systems serving between 3,300 and 10,000 people and a nationally representative sample of public water systems serving fewer than 3,300 people will need to collect samples for EPA, using sampling kits and following sampling instructions provided by the Agency's support contractor. EPA will notify small systems that are subject to UCMR participation.

EPA will arrange for sample analysis and will review monitoring results for small PWSs. After review, EPA will:

  • Release data to the PWSs through SDWARS
  • Notify their respective states that the data is available through SDWARS

PWSs should save the report as their official record.

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

As proposed, large systems will need to do the following:

  • Review instructions on accessing SDWARS through CDX
  • Report contact information to EPA through SDWARS
  • Review and, if necessary, revise their monitoring schedules established by EPA in SDWARS
  • Provide inventory information for each applicable sampling location
  • Collect samples for unregulated contaminants per the established schedule
  • Contract with approved UCMR 5 laboratories for analysis of their samples

In addition, PWSs are responsible for approving and submitting analytical results to EPA using SDWARS. PWSs will have 30 days after a laboratory posts data to act on their monitoring data. 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 for review and public release. After EPA review, UCMR 5 data reside in EPA's National Contaminant Occurrence Database (NCOD) and on UCMR's occurrence data page.

What do laboratories need to do?

Laboratories must be approved by EPA prior to analyzing and reporting results to SDWARS. Laboratories can only post data for methods for which they have received EPA approval. To receive EPA approval, laboratories must successfully participate in UCMR's laboratory approval program.

Laboratories granted EPA approval are obligated to report their data to SDWARS within 90 days of sample collection. Instructions on submitting data can be found in SDWARS.

What do states need to do?

States will have an opportunity to review PWS data upon PWS approval. States can review data through SDWARS.

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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

Unique name, assigned once by the PWS.

3. Public Water System Facility Identification Code

An identification code established by the State or, at the State’s discretion, by the PWS, following the format of a 5-digit number unique within each PWS for each applicable facility (i.e., for each source of water, treatment plant, distribution system, or any other facility associated with water treatment or delivery). The same identification code must be used to represent the facility for all current and future UCMR monitoring.

4. Public Water System Facility Name

Unique name, assigned once by the PWS, for every facility ID (e.g., Treatment Plant).

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 twelve-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 twelve-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 twelve-month period).
GW = ground water (to be reported for water facilities that are served entirely by a ground water source during the twelve-month period).

7. Sampling Point Identification Code

An identification code established by the State, or at the State’s discretion, by the PWS, that uniquely identifies each sampling point. Each sampling code must be unique within each applicable facility, for each applicable sampling location (i.e., entry point to the distribution system, source water influent or distribution system sample at maximum residence time). The same identification code must be used to represent the sampling location for all current and future UCMR monitoring.

8. Sampling Point Name

Unique sample point name, assigned once by the PWS, for every sample point ID (e.g., Entry Point).

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, SCO, 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 4-digit year, 2-digit month, and 2-digit day (YYYY/MM/DD).

13. Sample Identification Code

An alphanumeric value up to 30 characters assigned by the laboratory to uniquely identify containers, or groups of containers, containing water samples collected at the same sampling location for the same sampling date.

14. Contaminant

The unregulated contaminant for which the sample is being 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 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 Results—Sign

A value indicating whether the sample analysis result was:
(<) “less than” means the contaminant was not detected, or was detected at a level below the Minimum Reporting Level.
(=) “equal to” means the contaminant was detected at the level 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 assigned by the PWS for each sample event. This will associate samples with the PWS monitoring plan to allow EPA to track compliance and completeness. Systems must assign the following codes:
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, SCO, INF, DFL, or SSF)
  • IEX = Ionic exchange
    Nanofiltration and reverse osmosis
  • OZON = Ozone
    Biologically Active Carbon
  • MFL = Membrane filtration
  • ULVL = Ultraviolet light
    Other
NO = have never tested for the contaminant
DK = I 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, 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 = I am not aware of any potential current and/or historical sources
DK = I do not know
28. Direct Potable Reuse Water Information A yes or no answer provided by the PWS for each entry point to the distribution system. 
Question: Do you use direct potable reuse as a source of water?
YES = If yes, what is the blending ratio when used?
  • Enter blending ratio at sample point
NO = do not use direct potable reuse water

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