East Liverpool City Water System

MyTapWater.org's tap water quality report is the compilation of data collected from federal, state, and local government agencies, most prominently the EPA. We strive to populate the report with the latest data concerning water contaminants, lead and copper levels, and water quality violations. We only collect drinking water data from public water systems.

PWS Service Information
PWS ID: OH1500811
Type: Community water system
EPA Region: 05
Primary Service Area: Residential Area
Primary Source: Surface water
Population Served: 10,951
Contact Information
WRIGHT, ROBERT
WRIGHT, ROBERT
2220 MICHIGAN AVE
EAST LIVERPOOL, OH 43920
[email protected]

This public water system services 1 municipality in 1 county.

Summary Results


A summary view of tests in which a water contaminant found to exceed the Maximum Contaminant Level (MCL) set by the EPA.

Maximum Contaminant Levels Exceeded (by year):

Contaminant Detailed Results


This a view of violations of maximum contaminant levels. Use the expanded view see result data for a drinking water contaminant, the minimum level that can be recognized in a test (MRL), and upper limit that is considered healthy (HRL).

HAA5

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0 0.00 25.02
2018 2018-05-09 0 0.00 40.61
2018 2018-05-09 0 0.00 24.06
2018 2018-05-09 0 0.00 32.07

HAA6Br

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0 0.00 11.5
2018 2018-05-09 0 0.00 13.19
2018 2018-05-09 0 0.00 12.05
2018 2018-05-09 0 0.00 12.72

HAA9

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0 0.00 35.4
2018 2018-05-09 0 0.00 52.79
2018 2018-05-09 0 0.00 34.95
2018 2018-05-09 0 0.00 43.72

1-butanol

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 2 0.00 < 2

2-methoxyethanol

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.4 0.00 < 0.4

2-propen-1-ol

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.5 0.00 < 0.5

alpha-hexachlorocyclohexane

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.01 0.00 < 0.01

butylated hydroxyanisole

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.03 0.00 < 0.03

chlorpyrifos

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.03 0.00 < 0.03

dimethipin

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.2 0.00 < 0.2

ethoprop

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.03 0.00 < 0.03

germanium

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.3 0.00 < 0.3

manganese

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.4 0.00 1.59

o-toluidine

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.007 0.00 < 0.007

oxyfluorfen

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.05 0.00 < 0.05

profenofos

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.3 0.00 < 0.3

quinoline

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.02 0.00 < 0.02

tebuconazole

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.2 0.00 < 0.2

total permethrin

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.04 0.00 < 0.04

tribufos

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-05-09 0.07 0.00 < 0.07

chlorate

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2013 2013-12-10 20 210 232
2013 2013-12-10 20 210 216
2013 2013-09-10 20 210 1010
2013 2013-09-10 20 210 862
2013 2013-06-11 20 210 260
2013 2013-06-11 20 210 268
2013 2013-03-13 20 210 125
2013 2013-03-12 20 210 126

Other Water Contaminants Tested


The following contaminants were tested and found to be within national EPA guidelines.

Contaminant MRLMinimum Reporting Level HRLHealth Risk Limit Avg Result
1,1-dichloroethane 0.03 6.14 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.03 6.14 < 0.03
2013 2013-09-10 0.03 6.14 < 0.03
2013 2013-06-11 0.03 6.14 < 0.03
2013 2013-03-12 0.03 6.14 < 0.03
1,2,3-trichloropropane 0.03 0.0004 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.03 0.0004 < 0.03
2013 2013-09-10 0.03 0.0004 < 0.03
2013 2013-06-11 0.03 0.0004 < 0.03
2013 2013-03-12 0.03 0.0004 < 0.03
1,3-butadiene 0.1 0.0103 < 0.1 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.1 0.0103 < 0.1
2013 2013-09-10 0.1 0.0103 < 0.1
2013 2013-06-11 0.1 0.0103 < 0.1
2013 2013-03-12 0.1 0.0103 < 0.1
1,4-dioxane 0.07 0.35 < 0.07 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.07 0.35 < 0.07
2013 2013-09-10 0.07 0.35 < 0.07
2013 2013-07-10 0.07 0.35 < 0.07
2013 2013-03-12 0.07 0.35 < 0.07
bromomethane 0.2 140 < 0.2 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.2 140 < 0.2
2013 2013-09-10 0.2 140 < 0.2
2013 2013-06-11 0.2 140 < 0.2
2013 2013-03-12 0.2 140 < 0.2
chloromethane 0.2 2.69 < 0.2 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.2 2.69 < 0.2
2013 2013-09-10 0.2 2.69 < 0.2
2013 2013-06-11 0.2 2.69 < 0.2
2013 2013-03-12 0.2 2.69 < 0.2
chromium 0.2 100 0.1561 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.2 100 < 0.2
2013 2013-12-10 0.2 100 < 0.2
2013 2013-09-10 0.2 100 < 0.2
2013 2013-09-10 0.2 100 < 0.2
2013 2013-06-11 0.2 100 0.591
2013 2013-06-11 0.2 100 0.658
2013 2013-03-13 0.2 100 < 0.2
2013 2013-03-12 0.2 100 < 0.2
chromium-6 0.03 0 0.0695 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.03 0 0.056
2013 2013-12-10 0.03 0 0.064
2013 2013-09-10 0.03 0 0.058
2013 2013-09-10 0.03 0 0.069
2013 2013-06-11 0.03 0 0.09
2013 2013-06-11 0.03 0 0.083
2013 2013-03-13 0.03 0 0.077
2013 2013-03-12 0.03 0 0.059
cobalt 1 70 < 1 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 1 70 < 1
2013 2013-12-10 1 70 < 1
2013 2013-09-10 1 70 < 1
2013 2013-09-10 1 70 < 1
2013 2013-06-11 1 70 < 1
2013 2013-06-11 1 70 < 1
2013 2013-03-13 1 70 < 1
2013 2013-03-12 1 70 < 1
Halon 1011 0.06 90 < 0.06 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.06 90 < 0.06
2013 2013-09-10 0.06 90 < 0.06
2013 2013-06-11 0.06 90 < 0.06
2013 2013-03-12 0.06 90 < 0.06
HCFC-22 0.08 0 < 0.08 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.08 0 < 0.08
2013 2013-09-10 0.08 0 < 0.08
2013 2013-06-11 0.08 0 < 0.08
2013 2013-03-12 0.08 0 < 0.08
molybdenum 1 40 0.9925 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 1 40 < 1
2013 2013-12-10 1 40 < 1
2013 2013-09-10 1 40 1.7
2013 2013-09-10 1 40 1.4
2013 2013-06-11 1 40 1.39
2013 2013-06-11 1 40 1.28
2013 2013-03-13 1 40 1.06
2013 2013-03-12 1 40 1.11
PFBS 0.09 0 < 0.09 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.09 0 < 0.09
2013 2013-09-10 0.09 0 < 0.09
2013 2013-06-11 0.09 0 < 0.09
2013 2013-03-12 0.09 0 < 0.09
PFHpA 0.01 0 < 0.01 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.01 0 < 0.01
2013 2013-09-10 0.01 0 < 0.01
2013 2013-06-11 0.01 0 < 0.01
2013 2013-03-12 0.01 0 < 0.01
PFHxS 0.03 0 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.03 0 < 0.03
2013 2013-09-10 0.03 0 < 0.03
2013 2013-06-11 0.03 0 < 0.03
2013 2013-03-12 0.03 0 < 0.03
PFNA 0.02 0 < 0.02 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.02 0 < 0.02
2013 2013-09-10 0.02 0 < 0.02
2013 2013-06-11 0.02 0 < 0.02
2013 2013-03-12 0.02 0 < 0.02
PFOA 0.02 0.07 < 0.02 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.02 0.07 < 0.02
2013 2013-09-10 0.02 0.07 < 0.02
2013 2013-06-11 0.02 0.07 < 0.02
2013 2013-03-12 0.02 0.07 < 0.02
PFOS 0.04 0.07 < 0.04 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.04 0.07 < 0.04
2013 2013-09-10 0.04 0.07 < 0.04
2013 2013-06-11 0.04 0.07 < 0.04
2013 2013-03-12 0.04 0.07 < 0.04
strontium 0.3 1500 143.5 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.3 1500 100
2013 2013-12-10 0.3 1500 120
2013 2013-09-10 0.3 1500 160
2013 2013-09-10 0.3 1500 150
2013 2013-06-11 0.3 1500 117
2013 2013-06-11 0.3 1500 141
2013 2013-03-13 0.3 1500 177
2013 2013-03-12 0.3 1500 183
vanadium 0.2 21 0.081 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2013 2013-12-10 0.2 21 < 0.2
2013 2013-12-10 0.2 21 < 0.2
2013 2013-09-10 0.2 21 0.2
2013 2013-09-10 0.2 21 < 0.2
2013 2013-06-11 0.2 21 0.231
2013 2013-06-11 0.2 21 0.217
2013 2013-03-13 0.2 21 < 0.2
2013 2013-03-12 0.2 21 < 0.2

Lead and Copper Data


Lead and copper are recorded separately from other contaminants because of the Lead and Copper Rule. As with all other results, these are the findings at the water supply level. Lead and copper can be — and often are — deposited in drinking water in between the water facility and your tap.

Sample ID Contaminant Sampling Start Date Sampling End Date Result
OH67216 lead 2016-01-01 2018-12-31 0.0075mg/L
OH62030 lead 2013-01-01 2015-12-31 0.013mg/L
OH57294 lead 2010-01-01 2012-12-31 0.0029mg/L
OH51406 lead 2008-01-01 2010-12-31 0.0031mg/L

Violations


Known violations of the Safe Drinking Water Act as recorded by the EPA.

Compliance Dates Rule Violation Type Contaminant Name Status
2008-01-01 - 2010-12-31 Synthetic Organic Chemicals Monitoring, Regular 2,3,7,8-TCDD Known
2002-05-01 - 2002-07-31 Synthetic Organic Chemicals Monitoring, Regular Simazine Returned to Compliance
2002-05-01 - 2002-07-31 Synthetic Organic Chemicals Monitoring, Regular Atrazine Returned to Compliance
2002-05-01 - 2002-07-31 Synthetic Organic Chemicals Monitoring, Regular LASSO Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Toluene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Carbon tetrachloride Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular CHLOROBENZENE Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Xylenes, Total Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Benzene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular cis-1,2-Dichloroethylene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular DICHLOROMETHANE Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Vinyl chloride Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Ethylbenzene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Trichloroethylene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular trans-1,2-Dichloroethylene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,2,4-Trichlorobenzene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Tetrachloroethylene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,2-Dichloropropane Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular o-Dichlorobenzene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,2-Dichloroethane Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular Styrene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,1,2-Trichloroethane Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular p-Dichlorobenzene Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,1,1-Trichloroethane Returned to Compliance
2002-01-01 - 2002-06-30 Volatile Organic Chemicals Monitoring, Regular 1,1-Dichloroethylene Returned to Compliance
2002-02-01 - 2002-04-30 Synthetic Organic Chemicals Monitoring, Regular LASSO Returned to Compliance
2002-02-01 - 2002-04-30 Synthetic Organic Chemicals Monitoring, Regular Simazine Returned to Compliance
2002-02-01 - 2002-04-30 Synthetic Organic Chemicals Monitoring, Regular Atrazine Returned to Compliance
2001-06-01 - 2001-08-31 Total Coliform Rule Monitoring, Routine Major (TCR) Coliform (TCR) Returned to Compliance
2001-05-01 - 2001-07-31 Synthetic Organic Chemicals Monitoring, Regular Simazine Returned to Compliance
2001-05-01 - 2001-07-31 Synthetic Organic Chemicals Monitoring, Regular LASSO Returned to Compliance
2001-05-01 - 2001-07-31 Synthetic Organic Chemicals Monitoring, Regular Atrazine Returned to Compliance
- N/A Synthetic Organic Chemicals Monitoring, Regular Toxaphene Known
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Toluene Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Tetrachloroethylene Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Styrene Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular 1,1-Dichloroethylene Returned to Compliance
- N/A Lead and Copper Rule Water Quality Parameter M/R Lead and Copper Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular trans-1,2-Dichloroethylene Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Trichloroethylene Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Vinyl chloride Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Xylenes, Total Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance
2002-07-01 - N/A Long Term 1 Enhanced Surface Water Treatment Rule Failure Submit Filter Profile/CPE Report Interim Enhanced Surfsce Water Treatment Rule Returned to Compliance
- N/A Arsenic Monitoring, Regular Arsenic Known
- N/A Volatile Organic Chemicals Monitoring, Regular CHLOROBENZENE Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular Carbon tetrachloride Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Cadmium Known
- N/A Synthetic Organic Chemicals Monitoring, Regular BHC-GAMMA Known
- N/A Volatile Organic Chemicals Monitoring, Regular Benzene Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Barium Known
- N/A Synthetic Organic Chemicals Monitoring, Regular Atrazine Returned to Compliance
- N/A Arsenic Monitoring, Regular Arsenic Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Chromium Known
- N/A Synthetic Organic Chemicals Monitoring, Regular 2,4,5-TP Known
- N/A Synthetic Organic Chemicals Monitoring, Regular 2,4-D Known
- N/A Volatile Organic Chemicals Monitoring, Regular 1,2,4-Trichlorobenzene Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular 1,2-Dichloropropane Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular 1,2-Dichloroethane Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular 1,1,2-Trichloroethane Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular 1,1,1-Trichloroethane Returned to Compliance
- N/A Synthetic Organic Chemicals Monitoring, Regular Simazine Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular cis-1,2-Dichloroethylene Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular DICHLOROMETHANE Returned to Compliance
- N/A Synthetic Organic Chemicals Monitoring, Regular Endrin Known
- N/A Volatile Organic Chemicals Monitoring, Regular Ethylbenzene Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Fluoride Known
- N/A Inorganic Chemicals Monitoring, Regular Fluoride Returned to Compliance
- N/A Synthetic Organic Chemicals Monitoring, Regular LASSO Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Mercury Known
- N/A Synthetic Organic Chemicals Monitoring, Regular Methoxychlor Known
- N/A Nitrates Monitoring, Regular Nitrate Known
- N/A Nitrates Monitoring, Regular Nitrate Known
- N/A Nitrates Monitoring, Regular Nitrate Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular o-Dichlorobenzene Returned to Compliance
- N/A Volatile Organic Chemicals Monitoring, Regular p-Dichlorobenzene Returned to Compliance
- N/A Inorganic Chemicals Monitoring, Regular Selenium Known

Local Water Testing


Find a lab in your area so you can get your tap or well water tested. This list contains both governmental and private labs, all of which are EPA-certified for drinking water testing.

Unable to identify any nearby water testing labs near 43920.

Water Bill Information


Convenient information about your water service.

Unable to identify any billing information about East Liverpool City (OH1500811).

What My Water Data Means


Water data isn't always easy to interpret, but by following the links on this page you should be able to have most of your questions answered. By clicking the name of a water contaminant or secondary substance you can learn about that specific substance. Ultimately this page should give you some insight towards learning if your water is safe, what water filter you should buy (if any), and how well your local water compares against other sources.

Sources


The origin of MyTapWater.org's water data is explained on our Data Sources page.

Why Is My Water Data Not More Recent?


The recency of the data for your ZIP code depends on the last your water source was tested, by a federal, state, or local agency. More information about the timing can be determined by learning about the dataset in question and seeing how often the EPA (other another governing body) mandated testing.