2002 Annual Drinking Water Quality Report

For

Central Wyoming Regional Water System

1500 SW Wyoming Blvd.

Casper WY 82604

(307) 265-6063

We're pleased to present to you this year’s Annual Quality Water Report. This report is designed to inform you about the quality water and services we deliver to you every day. Our constant goal is to provide you with a safe and dependable supply of drinking water. We want you to understand the efforts we make to continually improve the water treatment process and protect our water resources. We are committed to ensuring the quality of your water. Our water source consists of twenty-one ground water wells and surface water drawn from the North Platte River.

We are pleased to report to our consumers that our drinking water is safe and meets Federal and State requirements.

If you have any questions about this report or concerning your water utility, please contact Steve Garner at (307) 265-6063. We want our valued customers to be informed about their water utility. If you want to learn more, please attend any of our regularly scheduled meetings. They are held on the third Wednesday of every month at 5:30 PM located at 1500 SW Wyoming Blvd.

Central Wyoming Regional Water System (CWRWS) routinely monitors for constituents in your drinking water according to Federal and State laws. This table shows the results of our monitoring for the period of January 1^st to December 31^st, 2002. As water travels over the land or underground it can pick up substances or contaminants such as microbes, inorganic and organic chemicals, and radioactive substances. All drinking water, including bottled drinking water, may be reasonably expected to contain at least small amounts of some constituents. It's important to remember that the presence of these constituents does not necessarily pose a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline at 1-800-426-4791.

In this table you will find many terms and abbreviations you might not be familiar with. To help you better understand these terms we've provided the following definitions:

Non-Detects (ND) - laboratory analysis indicates that the laboratory does not detect the constituent.

Parts per million (ppm) or Milligrams per liter (mg/l) - one part per million corresponds to one minute in two years or a single penny in $10,000.

Parts per billion (ppb) or Micrograms per liter - one part per billion corresponds to one minute in 2,000 years, or a single penny in $10,000,000.

Nephelometric Turbidity Unit (NTU) - nephelometric turbidity unit is a measure of the clarity of water. Turbidity in excess of 5 NTU is just noticeable to the average person.

Action Level - the concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.

Treatment Technique (TT) - (mandatory language) A treatment technique is a required process intended to reduce the level of a contaminant in drinking water.

Maximum Contaminant Level - (mandatory language) The “Maximum Allowed” (MCL) is the highest level of a contaminant that is allowed in drinking water. MCL’s are set as close to the MCLG's as feasible using the best available treatment technology.

Maximum Contaminant Level Goal - (mandatory language) The “Goal”(MCLG) is the level of a contaminant in drinking water below which there is no known or expected risk to health. MCLG's allow for a margin of safety.

TEST RESULTS
Contaminant	Violation Y/N	Level Detected	Unit Measurement	MCLG	MCL	Likely Source of Contamination
Microbiological Contaminants
1. Total Coliform Bacteria	N	Negative	N/A	0	Presence of coliform bacteria in 5% of monthly samples	Naturally present in the environment
2. Fecal Coliform and E.coli	N	ND	CFU/100 ml	0	a routine sample and repeat sample are total coliform positive, and one is also fecal coliform or E. coli positive	Human and animal fecal waste
3. Turbidity	N	0.294	NTU	N/A	0.3	Soil runoff
Cryptosporidium	N	<1	CFU/100 ml	N/A	2-log removal	Animal and human fecal waste
Aerobic Spores	N	1.6	/100ml	N/A	N/A	Naturally present in the environment
Radioactive Contaminants
4. Beta/photon emitters	N/A	N/A	Mrem/yr	0	4	Decay of natural and man-made deposits
5. Alpha emitters	N	ND	pCi/1	0	15	Erosion of natural deposits
6. Combined radium	N/A	N/A	pCi/1	0	5	Erosion of natural deposits
Inorganic Contaminants
7. Antimony	N	ND	ppb	6	6	Discharge from petroleum refineries; fire retardants; ceramics; electronics; solder
8. Arsenic	N	ND	ppb	N/A	10	Erosion of natural deposits; runoff from orchards; runoff from glass and electronics production wastes
9. Asbestos	N/A	N/A	MFL	7	7	Decay of asbestos cement water mains; erosion of natural deposits
10. Barium	N	ND	ppb	2	2	Discharge of drilling wastes; discharge from metal refineries; erosion of natural deposits
11. Beryllium	N	ND	ppb	4	4	Discharge from metal refineries and coal-burning factories; discharge from electrical, aerospace, and defense industries
12. Cadmium	N	ND	ppb	5	5	Corrosion of galvanized pipes; erosion of natural deposits; discharge from metal refineries; runoff from waste batteries and paints
13. Chromium	N	ND	ppb	100	100	Discharge from steel and pulp mills; erosion of natural deposits
14. Copper (Source)	N	ND	ppm	1.3	AL=1.3	Corrosion of household plumbing systems; erosion of natural deposits; leaching from wood preservatives
14A. Copper (Pb&Cu Rule/Tap Monitoring) January to June 2000 July to December 2000	N N	0.89 0.75	ppm	1.3	AL=1.3	Corrosion of household plumbing systems; erosion of natural deposits; leaching from wood preservatives
15. Cyanide	N	ND	ppb	200	200	Discharge from steel/metal factories; discharge from plastic and fertilizer factories
16. Fluoride Surface Water Ground Water	N	0.4 0.4	ppm	4	4	Erosion of natural deposits; water additive which promotes strong teeth; discharge from fertilizer and aluminum factories
17. Lead (Source)	N	ND	ppb	0	AL=15	Corrosion of household plumbing systems, erosion of natural deposits
17. Lead (Pb&Cu Rule) January to June 2000 July to December 2000	N N	9 7	ppb	0	AL=15	Corrosion of household plumbing systems, erosion of natural deposits
18. Mercury (inorganic)	N	ND	ppb	2	2	Erosion of natural deposits; discharge from refineries and factories; runoff from landfills; runoff from cropland
19. Nitrate (as Nitrogen) Surface Water Ground Water	N	ND 0.3	ppm	10	10	Runoff from fertilizer use; leaching from septic tanks, sewage; erosion of natural deposits
20. Nitrite (as Nitrogen)	N	ND	ppm	1	1	Runoff from fertilizer use; leaching from septic tanks, sewage; erosion of natural deposits
21. Selenium	N	ND	ppb	50	50	Discharge from petroleum and metal refineries; erosion of natural deposits; discharge from mines
21A. Sodium Surface Water Ground Water	N	36 42	ppm	None	None	Natural occurring
22. Thallium	N	ND	ppb	0.5	2	Leaching from ore-processing sites; discharge from electronics, glass, and drug factories
Synthetic Organic Contaminants including Pesticides and Herbicides
23. 2,4-D	N	ND	ppb	70	70	Runoff from herbicide used on row crops
24. 2,4,5-TP (Silvex)	N	ND	ppb	50	50	Residue of banned herbicide
25. Acrylamide	N	ND	ppb	0	TT	Added to water during sewage/wastewater treatment
26. Alachlor	N	ND	ppb	0	2	Runoff from herbicide used on row crops
27. Atrazine	N	ND	ppb	3	3	Runoff from herbicide used on row crops
28. Benzo(a)pyrene (PAH)	N	ND	Nanograms/l	0	200	Leaching from linings of water storage tanks and distribution lines
29. Carbofuran	N	ND	ppb	40	40	Leaching of soil fumigant used on rice and alfalfa
30. Chlordane	N	ND	ppb	0	2	Residue of banned termiticide
31. Dalapon	N	ND	ppb	200	200	Runoff from herbicide used on rights of way
32. Di(2-ethylhexyl) adipate	N	ND	ppb	400	400	Discharge from chemical factories
33. Di(2-ethylhexyl) phthalate	N	ND	ppb	0	6	Discharge from rubber and chemical factories
34. Dibromochloropropane	N	ND	Nanograms/1	0	200	Runoff/leaching from soil fumigant used on soybeans, cotton, pineapples, and orchards
35. Dinoseb	N	ND	ppb	7	7	Runoff from herbicide used on soybeans and vegetables
36. Diquat	N	ND	ppb	20	20	Runoff from herbicide use
37. Dioxin [2,3,7,8-TCDD]	N/A	N/A	Picograms/l	0	30	Emissions from waste incineration and other combustion; discharge from chemical factories
38. Endothall	N	ND	ppb	100	100	Runoff from herbicide use
39. Endrin	N	ND	ppb	2	2	Residue of banned insecticide
40. Epichlorohydrin	N	ND	ppb	0	TT	Discharge from industrial chemical factories; an impurity of some water treatment chemicals
41. Ethylene dibromide	N	ND	Nanograms/1	0	50	Discharge from petroleum refineries
42. Glyphosate	N	ND	ppb	700	700	Runoff from herbicide use
43. Heptachlor	N	ND	Nanograms/1	0	400	Residue of banned termiticide
44. Heptachlor epoxide	N	ND	Nanograms/1	0	200	Breakdown of heptachlor
45. Hexachlorobenzene	N	ND	ppb	0	1	Discharge from metal refineries and agricultural chemical factories
46. Hexachlorocyclo- pentadiene	N	ND	ppb	50	50	Discharge from chemical factories
47. Lindane	N	ND	Nanograms/l	200	200	Runoff/leaching from insecticide used on cattle, lumber, gardens
48. Methoxychlor	N	ND	ppb	40	40	Runoff/leaching from insecticide used on fruits, vegetables, alfalfa, livestock
49. Oxamyl [Vydate]	N	ND	ppb	200	200	Runoff/leaching from insecticide used on apples, potatoes and tomatoes
50. PCBs [Polychlorinated biphenyls]	N	ND	Nanograms/1	0	500	Runoff from landfills; discharge of waste chemicals
51. Pentachlorophenol	N	ND	ppb	0	1	Discharge from wood preserving factories
52. Picloram	N	ND	ppb	500	500	Herbicide runoff
53. Simazine	N	ND	ppb	4	4	Herbicide runoff
54. Toxaphene	N	ND	ppb	0	3	Runoff/leaching from insecticide used on cotton and cattle

TEST RESULTS
Contaminant	Violation Y/N	Level Detected	Unit Measurement	MCLG	MCL	Likely Source of Contamination
Volatile Organic Contaminants
55. Benzene	N	ND	ppb	0	5	Discharge from factories; leaching from gas storage tanks and landfills
56. Carbon tetrachloride	N	ND	ppb	0	5	Discharge from chemical plants and other industrial activities
57. Chlorobenzene	N	ND	ppb	100	100	Discharge from chemical and agricultural chemical factories
58. o-Dichlorobenzene	N	ND	ppb	600	600	Discharge from industrial chemical factories
59. p-Dichlorobenzene	N	ND	ppb	75	75	Discharge from industrial chemical factories
60. 1,2 - Dichloroethane	N	ND	ppb	0	5	Discharge from industrial chemical factories
61. 1,1 – Dichloroethylene	N	ND	ppb	7	7	Discharge from industrial chemical factories
62. cis-1,2-Dichloroethylene	N	ND	ppb	70	70	Discharge from industrial chemical factories
63. trans - 1,2 –Dichloroethylene	N	ND	ppb	100	100	Discharge from industrial chemical factories
64. Dichloromethane	N	ND	ppb	0	5	Discharge from pharmaceutical and chemical factories
65. 1,2-Dichloropropane	N	ND	ppb	0	5	Discharge from industrial chemical factories
66. Ethylbenzene	N	ND	ppb	700	700	Discharge from petroleum refineries
67. Styrene	N	ND	ppb	100	100	Discharge from rubber and plastic factories; leaching from landfills
68. Tetrachloroethylene	N	ND	ppb	0	5	Leaching from PVC pipes; discharge from factories and dry cleaners
69. 1,2,4 –Trichlorobenzene	N	ND	ppb	70	70	Discharge from textile-finishing factories
70. 1,1,1 - Trichloroethane	N	ND	ppb	200	200	Discharge from metal degreasing sites and other factories
71. 1,1,2 –Trichloroethane	N	ND	ppb	3	5	Discharge from industrial chemical factories
72. Trichloroethylene	N	ND	ppb	0	5	Discharge from metal degreasing sites and other factories
73. Toluene	N	ND	ppm	1	1	Discharge from petroleum factories
74. Vinyl Chloride	N	ND	ppb	0	2	Leaching from PVC piping; discharge from plastics factories
75. Xylenes	N	ND	ppm	10	10	Discharge from petroleum factories; discharge from chemical factories
Disinfectants and Disinfection Byproducts
Average TTHM (Total trihalomethanes)	N	2.5	ppb	N/A	100	By-product of drinking water chlorination
Average HAA5 (Haloacetic Acids)	N	3.7	ppb	N/A	60	By-product of drinking water chlorination
Bromide (Source Water) Running Annual Average	N	0.077	ppm	n/a	n/a	Natural occurring
Bromate (Source Water) Running Annual Average	N	0.0052	ppm	0	0.01	Bromate is a by-product of using Ozone as a disinfectant if Bromide is present in the source water.

What does this mean?

As you can see by the table, our system had no violations. We’re proud that your drinking water meets or exceeds all Federal and State requirements. We have learned through our monitoring and testing that some constituents have been detected. The EPA has determined that your water is SAFE at these levels.

We constantly monitor the water supply for various contaminants. In May through September of 2002, we had 39 groundwater and 2 filtered surface water samples tested for Giardia and Cryptosporidium. These samples were analyzed using the ICR method with variations in the flotation-separation steps and staining steps, which have been shown to enhance recovery of cysts and oocysts. No fluorescing objects resembling Giardia cysts or Cryptosporidium oocysts were observed in the sample. This does not mean that any cysts or oocysts were present in the sample, only that none were present in the portion examined.

As part of the Interim Enhanced Surface Water Treatment Rule (IESWTR) regulation governing treatment for the pathogen Cryptosporidium (40 CFR Part 141, Subpart P), the U.S. Environmental Protection Agency (EPA) requires a treatment technique for 99% removal of Cryptosporidium. Water Systems using surface water or ground water under the direct influence of surface water (GWUDI) must comply with this new treatment technique starting in January 2002.

Currently, the CWRWS utilizes GWUDI from collection devices along the North Platte River: vertical wells, horizontal wells or caissons, and an infiltration gallery. This water is not treated in a filtration plant, but it is ozonated and disinfected with chloramines. Alternative filtration occurs through these devices, such as riverbank filtration occurring from the wells. Past operational data from the GWUDI system, and current microbial data being collected from the North Platte River and the combined GWUDI system water, indicates that the GWUDI system operates as an alternative filtration technology. The IESWTR provides that a PWS may use an alternative filtration technology if it demonstrates to the regulatory agency that the technology meets the treatment technique requirements. EPA is granting conditional removal credit to the CWRWS GWUDI system while a more detailed study is designed, and CWRWS completes the study to demonstrate the effectiveness of the alternative filtration technologies to remove Cryptosporidium. During the study period, the CWRWS will implement interim measures designed to ensure public health protection, using the multiple barriers of alternative filtration, and maximized inactivation with ozonation and chloramines. The turbidity of the water from individual GWUDI system devices will be continuously monitored, and turbidity performance requirements will be set for individual devices as well as the combined GWUDI system water. The CWRWS will have to meet all disinfectant byproduct regulations while maximizing ozone treatment, monitor the GWUDI system water and surface water sources for E. coli, Cryptosporidium, and coliphage, and meet all other monitoring and treatment technique requirements of the surface water treatment rules. This conditional approval of 2-log removal will expire on January 1, 2004.

Some of our data in the tables is more than one year old, since certain chemical contaminants are monitored less than once a year. Our sampling frequency complies with EPA drinking water regulations.

The sources of drinking water include rivers, lakes, streams, ponds, reservoirs, springs and wells. As water travels over the surface of the land or through the ground, it can dissolve naturally occurring minerals and, in some cases, radioactive materials. The water can also pick up substances such as:

1) Microbial contaminants, such as viruses and bacteria, which may come from sewage treatment plants, septic systems, agricultural operations and wildlife.

2) Inorganic contaminants, such as salts and metals, which can be naturally-occurring or result from urban storm water runoff, industrial or domestic waste water discharges, oil and gas production, mining or farming.

3) Pesticides and Herbicides, which may come from agriculture, urban storm water runoff, and residential uses.

4) Organic chemical contaminants, which can come from industrial processes, gas stations, urban storm water runoff and septic systems

5) Radioactive contaminants, which can be naturally occurring or the result of oil and gas production and mining activities.

In order to insure that tap water is safe to drink, EPA establishes regulations, which limit the amount of certain contaminants in water provided by public water systems. The Food and Drug Administration establishes limits for contaminants in bottled water.

MCL’s are set at very stringent levels. To understand the possible health effects described for many regulated constituents, a person would have to drink a half gallon of water every day at the MCL level for a lifetime to have a one-in-a-million chance of having the described health effect.

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. EPA/CDC guidelines on appropriate means to lessen the risk of infection by cryptosporidium and other microbiological contaminants are available from the Safe Drinking Water Hotline (800-426-4791) or EPA (800-227-8917).

We at the Central Wyoming Regional Water System work around the clock to provide top quality water to every tap. We ask that all our customers help us protect our water sources, which are the heart of our community, our way of life and our children’s future.