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EWG Statement, 03/10/2008

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NATIONAL SUMMARY

Quality Varies Across the U.S.

CONTAMINANTS DATABASE

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Tap Water Quality Report The State of Oregon 877 Water Systems Serving 2,887,811 People

An Environmental Working Group analysis of tap water tests from 1998 through 2003 for 877 communities across Oregon shows 32 pollutants were found in drinking water across the state.

Pollution Summary

32 10	7 1	8 3	26 7	4 3	14 4
Total pollutants	Agricultural pollutants	Sprawl and Urban pollutants	Industrial pollutants	Water Treatment and Distribution Byproducts	Naturally occurring pollutants
Number of pollutants detected (1998 - 2003)			Over health based limits

NOTE: Health based limits included in this analysis include enforceable drinking water limits (called Maximum Contaminant Limits, or MCLs) as well as governmental, non-enforceable health guidelines, such as Maximum Contaminant Limit Goals (MCLGs), lifetime health advisory levels, one-day and ten-day advisory levels to protect children from non-cancer health endpoints, and other government-established health guidelines for tap water contaminants.

Health Summary

The federal government has set standards for 80 chemical pollutants in tap water, balancing health concerns and treatment costs.

Contaminants found in state tap water (1998-2003): 32

Total population exposed above health-based limits: 567,167

Communities served water with contaminants above health-based limits: 188

Health effects or target organs of contaminants found: Cardiovascular or Blood Toxicity, Cancer, Developmental Toxicity, Endocrine Toxicity, Kidney Toxicity, Gastrointestinal or Liver Toxicity, Neurotoxicity, Reproductive Toxicity, Respiratory Toxicity, and Skin Sensitivity.

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Contaminants found above health based limits: 10

Rank	Contaminant Name	Population Exposed (of 2,887,811 Total)		Number of Water Systems (of 877) Total
		At Any Level	Above Health Limits See Note	With Detected	Above Health Limits See Note
1	Nitrate	1,512,050	6,421	463	4
		Chemical that enters water from fertilizer runoff, leaching septic tanks, and erosion of natural deposits
2	Combined Uranium (mg/L)	835,153	63,952	211	56
		Radioactive element commonly found in most rocks; processed ore used for power generation and weapons manufature.
3	Arsenic (total)	202,303	202,303	103	103
		Metal that enters water by erosion of natural deposits, runoff from glass and electronics processing
4	Total trihalomethanes (TTHMs)	720,008	252,145	29	25
		Measure of four disinfection by-products
5	Total haloacetic acids	263,870	26,220	27	5
		Measure of disinfection by-products; refers to the sum of the concentrations of dichloroacetic acid, trichloroacetic acid, monochloroacetic acid, monobromoacetic acid and dibromoacetic acid in a water sample.
6	Tetrachloroethylene	42,158	42,158	5	5
		Pollutant from dry cleaning and various industrial factories
7	Di(2-ethylhexyl) phthalate	1,064	1,064	3	3
		Pollutant from rubber and industrial chemical factories; leachate from PVC pipes
8	Radon	69,580	62,380	3	2
		natural (radioactive) breakdown product of uranium in soil, rock and water
9	Trichloroethylene	200	0	1	0
		Pollutant from metal degreasing sites
10	Carbon tetrachloride	3,360	3,360	1	1
		Pollutant from various chemical plants

NOTE: Health based limits included in this analysis include enforceable drinking water limits (called Maximum Contaminant Limits, or MCLs) as well as governmental, non-enforceable health guidelines, such as Maximum Contaminant Limit Goals (MCLGs), lifetime health advisory levels, one-day and ten-day advisory levels to protect children from non-cancer health endpoints, and other government-established health guidelines for tap water contaminants.

Testing Summary

The federal government has set standards for some of the pollutants found in tap water supplies.

Contaminants reported as tested by water suppliers in Oregon		86
	Contaminants tested due to federal law:	78
	Contaminants tested in addition to those required by federal law:	8

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Violations Summary

According to EPA, in 2003 6% of America's public water systems reported one or more violations of a health-based drinking water standard, and 26% reported significant violations of either monitoring and reporting requirements or health-based standards.

Reported violations (1998 - 2003): 7,549

Number of OR systems with violations: 815 (92.9%)

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Information on violations is drawn directly from EPA's national violations database in the Agency's Safe Drinking Water Information System. Analyses by others have raised questions about the quality of the information in EPA's database. For the purposes of this investigation, EWG is not showing below or including in our analyses, those violations for individual water suppliers that occurred on days for which the total number of violations assigned by EPA to that water supplier was greater than 20. This criteria was based on common characteristics of incorrect violations data as identified by water utilities, from a review of EPA's violations data by several hundred utilities prior to the release of EWG's investigation.