2005 Consumer Confidence Report
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Redwood Valley County Water District

Report Date:

June 22, 2006

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, 2005.

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Type of water source(s) in use:

Surface Water

Your water comes from Lake Mendocino. The District has an  intake structure and pump station on the west side of Lake Mendocino  at Winery Point. The water flows by gravity to our reservoir above  the District office. A separate pipeline delivers raw lake water to  the Districts treatment plant where we treat it to remove several contaminants  and also add disinfectant to protect you against microbial contaminants.

Drinking Water Source Assessment information: An assessment  of our source water was completed in April 2001 and is available for  review in the District Office during normal working hours, 8AM-5PM,  Monday - Friday.

Our Board of Directors meets on the Third Thursday of every  month at 7:00 pm in the District Office at 2370 Webb Ranch Road, Redwood  Valley, California. The District welcomes public involvement at these  meetings.

For more information  contact: 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.

Primary Drinking Water Standards (PDWS):  MCLs 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.

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)

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 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).

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 which a  water system must follow.

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

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

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 , which 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, and septic systems.

           Radioactive contaminants, which 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,  USEPA and the State Department of Health Services (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 requires us to monitor  for certain contaminants less than once per year because the concentrations  of these contaminants are not expected to vary significantly from year to  year. 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

Microbiological 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

Total Coliform Bacteria

(In a mo.)

0

0

More than 1 sample in a month with a detection

0

Naturally present in the environment

Fecal Coliform or
E. coli

(In the year)

0

0

A routine sample and a repeat sample detect total coliform and either  sample also detects fecal coliform or E. coli

0

Human and animal fecal waste

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

MCLG

Typical  Source of Contaminant

Lead (ppb)

Collected 9/8/04

23

<ND

0

15

2

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

Copper (ppm)

Collected 9/8/04

23

.45

0

1.3

0.17

Internal corrosion of household water  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)

3/30/05

4.9

n/a

none

none

Generally found in ground and surface  water

Hardness (ppm)

3/30/05

70

n/a

none

none

Generally found in ground and surface  water

*Any violation of an MCL or AL is denoted by an asterisk. Additional information  regarding the violation is provided on the next page.

  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

PHG
(MCLG)

Typical Source of Contaminant

  Aluminum (ppb)

monthly

40

10-40

1000

600

Erosion of natural deposits, residue  from surface water treatment process

 Asbestos (MFL)

 3/16/04

ND

n/a

7

(7)

Internal corrosion of asbestos cement  water mains, erosion of natural deposits

 Barium (ppb)

 3/30/05

53

n/a

1000

2

Discharges of oil drilling wastes  and from metal refineries; erosion of natural deposits

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

Chemical or Constituent
(and reporting units)

Sample Date

Level Detected

Range of Detections

Secondary MCL

PHG/  (MCLG)

Typical  Source of Contaminant 

Aluminum (ppb)

Monthl y

40

10-40

200

n/a

Erosion of natural deposits, residue  from surface water treatment processes. 

Chloride (ppm)

3/30/05

2.8

-----

500

n/a

Runoff/leaching from natural deposits;  seawater influence 

Manganese

6/11/05

*110*

12-110

50

n/a

Runoff/leaching from natural deposits 

Color

monthly

*5*

0-20

15

n/a

Naturally-occurring organic materials 

Iron (ppb)

6/11/05

N/D

-----

300

n/a

Leaching from natural deposits; industrial  wastes 

Odor - Threshold

monthly

*10.5*

0-50

3

n/a

Naturally occurring organic materials 

Specific Conductance (uMho)

3/30/05

160

-----

1600

n/a

Substances that form ions when in  water; seawater influence 

 Total Dissolved Solids (ppm)

3/30/05

93

-----

1000

n/a

Runoff/leaching from natural deposits 

 Sulfate (ppm)

3/30/05

7.3

-----

500

n/a

Runoff/leaching from natural deposits;  industrial wastes 

 Turbidity (NTU)

Cont.

.30

0.02-0.3

0.50

n/a

Soil runoff 

 Flouride (ppm) (naturally occurring)

3/30/05

<0.1

-----

2

1

Erosion of natural deposits 

 MBAS (ppb) foaming agents

3/30/05

<0.05

-----

500

n/a

Municipal & Industrial waste discharge 

  

 TTHMs-(Total Trihalomethanes)

RAA

*56*

MCL 80 ppb

Byproduct of Drinking Water chlorination 

 HAAs-(Halocetic Acids)

RAA

*39*

MCL 60 ppb

Byproduct of Drinking Water disinfection 

*Any violation of an MCL or AL is denoted by an asterisk. Additional information  regarding the violation is provided below.

RAA- Results are based on a running  annual average and may not reflect current compliance with MCLs.

Additional General Information on Drinking  Water

All 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 USEPAs 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).

Summary  Information for Contaminants Exceeding an MCL or AL, or a Violation of any  Treatment or Monitoring and Reporting Requirements

About our [TTHMs] Total  Trihalomethanes and [HAAs] Halocetic Acids Violation-  The regulation for these chemicals was adopted by the Department January  2005. These same levels of chemicals in your drinking water in 2004  were not exceeding the MCL. As we have previously reported to you,  we are working diligently, and in cooperation with the Department to  keep the levels of these chemicals, as  well as other contaminants, as low as possible. The water we are treating  at this time, and since August 2005 is below the MCL. We are reporting  the violations due to the levels present for the first (2) two quarters  of 2005 . In addition we have not exceeded MCL levels and are  far below MCL levels for 2006 . Some people who use water containing  trihalomethanes in excess of the MCL over many years may experience  liver, kidney, or central nervous system problems, and may have an increased  risk of getting cancer. Some people who drink water containing halocetic  acids in excess of the MCL over many years may have an increased risk  of getting cancer.

About our color, odor and manganese  secondary MCL violations : Secondary MCLs are based on aesthetic  qualities such as water taste, odor and appearance. Exceeding a secondary  MCL standard does NOT indicate a health based violation. Some changes  to treatment technique have already been implemented to help reduce  odor, color and manganese concentrations. We will continue to work  to ensure that these levels meet the secondary MCLs in the near future.  If we find that the current treatment technology does not allow for  sufficient removal of any of these compounds, you will be contacted  to discuss possible alternatives. If you are concerned about any violation  of a secondary MCL, you should discuss it with your elected represen

Table 7 - SAMPLING RESULTS SHOWING TREATMENT  OF SURFACE WATER SOURCES

Treatment Technique * (Type of approved filtration technology  used)

Conventional Filtration

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

Turbidity of the filtered water must:
1 - 1 - Be less than or equal to  0.5 NTU in 95% of measurements in a month.
2 2 - Not exceed 1.0 NTU for more  than eight consecutive hours.
3 - Not exceed 2.0 NTU at any time.

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

100%

Highest single turbidity measurement  during the year

0.30

The number of violations of any surface  water treatment requirements

0

tatives,  the General Manager, or the California Department of Health Services.

 

 

 

 

 

 

 

*A required process intended to reduce the level of a contaminant  in drinking water.

** 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
 

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