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Table 1: Perchlorate-contaminated drinking water sources in California

Rocket Fuel in Drinking Water: Table 1: Perchlorate-contaminated drinking water sources in California

March 3, 2003

Table 1. There are hundreds of perchlorate-contaminated drinking water sources in California.

County

Contaminated water sources (1)

Contaminated water systems (1)

Maximum perchlorate level detected (ppb) (2)

Contaminated sources still active (2)

Average level (ppb) in contaminated active sources (2)

Los Angeles

127

37

159

107

12.1

Orange

15

7

10.7

12

6.3

Riverside

49

8

65

40

9.7

Sacramento

13

3

400

0

-

San Bernardino

78

16

820

50

18.3

San Diego

1

1

4.7

1

4.5

Santa Clara (3)

133

4

8.5

3

6.2

Sonoma

1

1

5

1

4.5

Tulare

7

3

9.1

1

5.8

Ventura

2

1

20

2

11.6

Statewide

426

81

820

217

8.7

Source: EWG 2003



References

  1. California Department of Health Services (CADHS). 2003. California’s experience with perchlorate in drinking water. February 5, 2003. http://www.dhs.ca.gov/ps/ddwem/chemicals/perchl/monitoringupdate.htm

    Sweeney, F. 2003. Contamination may have spread; more San Martin wells to be tested. February 23, 2003. San Jose Mercury News.
  2. EWG analysis of California Department of Health Services (CADHS) drinking water quality database from June 2002 (CADHS 2002).
  3. Number includes 4 public drinking water wells and 129 private wells. A large new perchlorate plume in the San Martin area of Santa Clara County was discovered in late 2002, but testing of all potentially affected wells has not been completed. Wells that tested positive for perchlorate contamination but had concentrations lower than the "reporting limit" of 4 ppb were not included in this number.