2007 Consumer Confidence Report
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Water System Name: Redwood Valley County District                       Report Date: June 2007

We test the drinking water quality for many constituents as required by State and Federal Regulations.  This report shows the results of our monitoring for the period of January 1 - December 31, 2007.

The following tables summarize the test results only for those contaminants that were actually detected. Every year the District samples for many contaminants in many classes including metals, microbiological, pesticides, herbicides, industrial chemicals, and disinfectant by products. Most contaminants are not present in our source water.

Please be assured that the water produced by Redwood Valley County Water District meets all state and federal drinking water standards. If you do not see a contaminant listed in the following tables, it does not mean we did not test for it. It means we did not detect it.

Este informe contiene información muy importante sobre su agua potable. Tradúzcalo ó hable con alguien que lo entienda bien.

Your water is surface water from Lake Mendocino. The District has an intake structure and pump station on the west side of the lake at Winery Point. Untreated water is pumped to our storage reservoir near the District office. From there it flows by gravity either directly to our irrigation customers, or to our treatment plant. At the treatment plant, it is treated to meet all state and federal drinking water standards. Following treatment, disinfectant is added to protect you against microbial contaminants.

An Assessment of our Drinking Water Source was completed in September 2006. It is available for review at the District Office during normal working hours, 8 AM-5 PM, Monday-Friday. The Upper Eel River and Upper East Fork Russian River watersheds contain numerous septic tanks, a small wastewater treatment plant, and fuel and agricultural chemical storage tanks. Lake Mendocino is vulnerable to contamination from these sources. The District will continue to vigilantly monitor its source water for any possible contamination and treat the water appropriately.

The Board of Directors meets the third Thursday of every month at 7 PM in the District office located at 2370 Webb Ranch Road, Redwood Valley, CA 95470. The District welcomes public involvement at these meetings.

For more information, contact: William Koehler, General Manager  Phone: ( 707 )485-0679

TERMS USED IN THIS REPORT:

Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water.  Primary MCLs are set as close to the PHGs (or MCLGs) as is economically and technologically feasible.  Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.

Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health.  MCLGs are set by the U.S. Environmental Protection Agency (USEPA).

Public Health Goal (PHG): The level of a contaminant in drinking water below which there is no known or expected risk to health.  PHGs are set by the California Environmental Protection Agency.

Maximum Residual Disinfectant Level (MRDL):  The level of a disinfectant added for water treatment that may not be exceeded at the consumer's tap.

Maximum Residual Disinfectant Level Goal (MRDLG): The level of a disinfectant added for water treatment below which there is no known or expected risk to health. MRDLGs are set by the U.S. Environmental Protection Agency.

Primary Drinking Water Standards (PDWS): MCLs and MRDLs for contaminants that affect health along with their monitoring and reporting requirements, and water treatment requirements.

Secondary Drinking Water Standards (SDWS):  MCLs for contaminants that affect taste, odor, or appearance of the drinking water.  Contaminants with SDWSs do not affect the health at the MCL levels.

Treatment Technique (TT):  A required process intended to reduce the level of a contaminant in drinking water.

Regulatory Action Level (AL): The concentration of a contaminant which, if exceeded, triggers treatment or other requirements that a water system must follow.

Variances and Exemptions:  Department permission to exceed an MCL or not comply with a treatment technique under certain conditions.

ND: not detectable at testing limit 
ppm: parts per million or milligrams per liter (mg/L)
ppb: parts per billion or micrograms per liter (ug/L)
ppt: parts per trillion or nanograms per liter (ng/L)
pCi/L : picocuries per liter (a measure of radiation)

The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells.  As water travels over the surface of the land or through the ground, it dissolves naturally-occurring minerals and, in some cases, radioactive material, and can pick up substances resulting from the presence of animals or from human activity.

Contaminants that may be present in source water include:

  • Microbial contaminants, such as viruses and bacteria, that may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife.
  • Inorganic contaminants, such as salts and metals, that can be naturally-occurring or result from urban stormwater runoff, industrial or domestic wastewater discharges, oil and gas production, mining, or farming.
  • Pesticides and herbicides, that may come from a variety of sources such as agriculture, urban stormwater runoff, and residential uses.
  • Organic chemical contaminants, including synthetic and volatile organic chemicals, that are byproducts of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, agricultural application, and septic systems.
  • Radioactive contaminants, that can be naturally-occurring or be the result of oil and gas production and mining activities.

In order to ensure that tap water is safe to drink, the USEPA and the state Department of Public Health (Department) prescribe regulations that limit the amount of certain contaminants in water provided by public water systems.  Department regulations also establish limits for contaminants in bottled water that must provide the same protection for public health.

Tables 1, 2, 3, 4, and 5 list all of the drinking water contaminants that were detected during the most recent sampling for the constituent.  The presence of these contaminants in the water does not necessarily indicate that the water poses a health risk.  The Department allows us to monitor for certain contaminants less than once per year because the concentrations of these contaminants do not change frequently.  Some of the data, though representative of the water quality, are more than one year old.

Table 1 - sampling results showing the detection of coliform bacteria

Contaminants
(to be completed only if there was a detection of bacteria )

Highest No. of detections

No. of months in violation

MCL

MCLG

Typical Source of Bacteria

None detected

0

0

1 per month, total coliform

0

Naturally present in the environment

Table 2 - sampling results showing the detection of Lead and copper

Lead and Copper
(to be completed only if there was a detection of lead or copper in the last sample set)

No. of samples collected

90th percentile level detected

No. sites exceeding AL

AL

PHG

Typical Source of Contaminant

 

Lead (ppb)
Collected August 2007

20

None detected

0

15

2

Internal corrosion of household water plumbing systems; discharges from industrial manufacturers; erosion of natural deposits

Copper (ppm)
Collected August 2007

20

0.20

0

1.3

0.17

Internal corrosion of household plumbing systems; erosion of natural deposits; leaching from wood preservatives

TAble 3 - sampling results for sodium and hardness

Chemical or Constituent (and reporting units)

Sample Date

Level Detected

Range of Detections

MCL

PHG
(MCLG)

Typical Source of Contaminant

Sodium (ppm)

3/28/07

6.2

n/a

none

none

Generally found in ground & surface water

Hardness (ppm)

3/28/07

81

n/a

none

none

Generally found in ground & surface water

* Any violation of an MCL or AL is marked with an asterisk.  Additional information regarding the violation is provided later in this report.

TAble 4 - detection of contaminants with a Primary Drinking Water Standard

Chemical or Constituent
(and reporting units)

Sample Date

Level Detected

Range of Detections

MCL
[MRDL]

PHG
(MCLG)
[MRDLG]

Typical Source of Contaminant

Trihalomethanes (ppb)

Quarterly
RAA

31

1-45

80

n/a

Byproduct of drinking water chlorination

Haloacetic acids (ppb)

Quarterly
RAA

22

4-30

60

n/a

Byproduct of drinking water chlorination

Total Organic Carbon (ppm)

monthly

4

2-4

TT

n/a

Various manmade and natural sources

Gross Alpha Particle Activity (pCi/L)

3/28/07

2

n/a

15

0

Erosion of natural deposits

Aluminum (ppb)

3/28/07

250

n/a

1000

600

Erosion of natural deposits; residue from some surface water treatment processes.

TAble 5 - detection of contaminants with a Secondary Drinking Water Standard

Chemical or Constituent
(and reporting units)

Sample Date

Level Detected

Range of Detections

MCL

PHG
(MCLG)

Typical Source of Contaminant

Aluminum *(ppb)

3/28/07

250*

n/a

200

n/a

Erosion of natural deposits; residue from some surface water treatment processes.

Chloride (ppm)

3/28/07

3

n/a

500

n/a

Run off/leaching from natural deposits

Color (units)

1/22/07;
2/21/07

5

5

15

n/a

Naturally occurring organic matter

Odor (threshold)

Monthly

2

0-2

3

n/a

Naturally occurring organic matter

Specific conductance (us/cm)

3/28/07

160

n/a

1600

n/a

Substances that form ions in water

Aluminum (ppm)

3/28/07

250

n/a

1000

n/a

Run off/leaching from natural deposits

Total dissolved solids

3/28/07

110

n/a

1000

n/a

Run off/leaching from natural deposits

TABLE 6 - DETECTION OF UNREGULATED CONTAMINANTS

Chemical or Constituent(and reporting units)

Sample Date

Level Detected

Notification Level

Health Effects Language

Boron (ppb)

 

12/20/07

340

1000

The babies of some pregnant women who drink water containing Boron in excess of the notification level may have an increased risk of developmental effects, based on studies in laboratory animals.

* Any violation of an MCL, MRDL, or TT is asterisked.  Additional information regarding the violation is provided later in this report.

Summary Information for Contaminants Exceeding an MCL, MRDL, or AL, or a Violation of Any Treatment Technique or Monitoring and Reporting Requirement

* Aluminum. Some people who drink water containing aluminum in excess of the MCL over many years may experience short term gastrointestinal tract effects.

Additional General Information on Drinking Water

Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants.  The presence of contaminants does not necessarily indicate that the water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the USEPA's Safe Drinking Water Hotline (1-800-426-4791).

Some people may be more vulnerable to contaminants in drinking water than the general population.  Immuno-compromised persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. USEPA/Centers for Disease Control (CDC) guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the Safe Drinking Water Hotline (1-800-426-4791).

For Systems Providing Surface Water as a Source Of Drinking Water:
(Refer to page 1, "Type of water source in use" to see if your source of water is surface water or groundwater)

Table 7 - sampling results showing TREATMENT OF  SURFACE WATER SOURCES

Treatment Technique (a)
(Type of approved filtration technology used)

 

Turbidity Performance Standards (b)
(that must be met through the water treatment process)

Turbidity of the filtered water must:
1 – Be less than or equal to _0.30_ NTU in 95% of measurements in a month.
2 – Not exceed _1__ NTU for more than eight consecutive hours.
3 – Not exceed _2_ NTU at any time.

Lowest monthly percentage of samples that met Turbidity Performance Standard No. 1.

100%

Highest single turbidity measurement during the year

0.15 NTU

Number of violations of any surface water treatment requirements

0

    (a) A required process intended to reduce the level of a contaminant in drinking water.
    (b) Turbidity (measured in NTU) is a measurement of the cloudiness of water and is a good indicator of water quality and filtration performance.  Turbidity results which meet performance standards are considered to be in compliance with filtration requirements.
    * Any violation of a TT is marked with an asterisk.  Additional information regarding the violation is provided earlier in this report.

 

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