Annual Drinking Water Quality Report 2019

C O M M I T T E D T O O P E R A T I O N A L E X C E L L E N C E

MOUNT PLEASANT WATERWORKS

Dear Waterworks Customers,I am proud to present your Annual Drinking Water Quality Report. The drinking water analysis data provided in this report summarizes water quality test results for 2019.

Mount Pleasant Waterworks (MPW) continues to meet or exceed every federal and state drinking water standard. Our team of more than 150 employees is committed to working 24/7 to protect your drinking water and the environment. Please take this opportunity to learn more about your water quality, water source, and the treatment process.

Thank you for your continued support of the men and women at MPW who strive to provide our community with clean water every day.

Sincerely,

Clay Duffie, General Manager

Your water comes from the Charleston Aquifer, a pristine groundwater source estimated to be more than 50,000 years old. Six wells are drilled at an average of 2,000 feet below the earth’s surface and raw water is pumped to four Reverse Osmosis (RO) treatment plants and disinfected with chloramines. Additional water is purchased under a wholesale contract with Charleston Water System to help supplement water demand in the Mount Pleasant area. This additional drinking water is sourced from the Bushy Park Reservoir and the Edisto River, treated by conventional water treatment, and disinfected with chloramines. You can find more details on this additional source at http://charlestonwater.com/DocumentCenter/View/1911/2019CCR_Final. A complete source water assessment is available upon request.

Where does my water come from?

MPW Service AreaMount Pleasant Waterworks serves more than 90,000 people in the vibrant and thriving Mount Pleasant community. The MPW treatment and distribution system is comprised of approximately 550 miles of conveyance pipe, four RO water treatment plants, six deep wells, eight ground storage tanks, one operational elevated tank, three aquifer storage and recovery (ASR) wells, and two wholesale water intakes.

NORTHMT. PLEASANT

DANIELISLAND

526

17

17

ARTHUR RAVENEL BRIDGE

BEN SAW

YER BLVD.

COLEMAN BLVD.

CHARLESTON HARBOR

ATLANTICOCEAN

MARKET ATOAKLAND

ISLE OF PALMS

MT. PLEASANT

SEWEE RD.

17

41

IOP CONNECTOR

RIFLE RANGE RD.

23

4

1

21

2

LEGENDWater Treatment Plant

Ground Storage

Elevated Storage

Deep Wells

Purchased Surface Water

ASR Wells

Service Area

RO Dispensers

23

1

2

4

3

6

5

1

�������

�������

�������

�

������

� ����

����

������

�����

������

�����

��������

������

������

�������

�������

�

�������

������

�����

���������������������������������������

������������������ ����­����

�����­���

����������� �����

������������� �����

�������������

�������������������������

����� ����������

Reverse Osmosis (RO) water dispensers are located at three RO water treatment plants:

Plant 1 King St. near the corner of Simmons St. (Old Village)

Plant 2 7th Ave. near the corner of Mathis Ferry Rd.

Plant 3 Labor Camp Rd. off Venning Rd.

MPW 2019 Water Quality Report 1www.mountpleasantwaterworks.com

Regulated and Unregulated Water Quality MonitoringIn order to ensure that tap water is safe to drink, the Environmental Protection Agency (EPA) prescribes regulations which limit the amount of constituents in water provided by public water systems. The constituents presented in the below tables reflect only those detected during the 2019 testing period; although many more were tested. All sources of drinking water contain some naturally occurring constituents. Removing all constituents would be extremely expensive, and in most cases, would not provide increased protection of public health. Furthermore, because concentrations of certain constituents do not vary significantly from year to year and/or MPW is not considered vulnerable to a specific type of contamination, monitoring requirements by S.C. Department of Health and Environmental Control (SCDHEC) are less than once per year. As such, some data, though representative, may be more than one year old. Please refer to the glossary of terms for an explanation of the abbreviations and terms used in the tables.

MPW’S WATER QUALITY

Constituent

MCLG or

MRDLG

MCL, TT, or MRDL

Highest Level Detected In Your Water

RangeSample

Date Violation Typical SourceLow HighDisinfectants & Disinfection By-ProductsChloramine (as Cl2) (ppm) 4 4 RAA=2.4 1.9 2.5 2019 No Water additive used to control microbesHaloacetic Acids (HAA5) (ppb) NA 60 16.59 ND 16.59 2019 No

By-product of drinking water disinfectionTTHMs [Total Trihalomethanes] (ppb) NA 80 13.32 ND 13.32 2019 NoInorganic Constituents

Fluoride (ppm) 4 4 0.54 NA 2019 NoErosion of natural deposits

Sodium (ppm) MNR 69 22 76 2017-2019 NoMicrobiological Constituents

Total Coliform (RTCR)<5%

positive samples per month

TT2.1%

all repeat samples were satisfactory

0 2.1% 2019 No Naturally present in the environment

Radioactive ConstituentsAlpha emitters (pCi/L) 0 15 2.96 ND 2.96 2019 No Erosion of natural depositsUnregulated Contaminant Monitoring (UCMR 4)HAABr6 MNR 3.99 ND 7.15 2019 EPA uses the Unregulated Contaminant Monitoring Rule (UCMR) to collect data

for contaminants that are suspected to be present in drinking water and do not have health-based standards set under the Safe Drinking Water Act (SDWA).

HAA9 MNR 10.23 0.318 18.5 2019

Manganese MNR 6.41 0.678 10.4 2019

DRINKING WATER ANALYSIS DATA FOR 2019

PURCHASED SURFACE WATER QUALITY

Constituent

MCLG or

MRDLG

MCL, TT, or MRDL

Highest Level Detected in Your Water

Range

Sample Date Violation Typical SourceLow High

Disinfectants

Chloramine (as Cl2) (ppm) 4 4 RAA= 2.7 2.5 2.9 2019 No Water additive used to control microbes

Inorganic Constituents

Fluoride (ppm) 4 4 0.43 NA 2019 No Erosion of natural deposits; Water additive which promotes strong teeth; Discharge from fertilizer and aluminum factories

Nitrate [measured as Nitrogen] (ppm) 10 10 0.12 NA 2019 No Runoff from fertilizer use; Leaching from septic tanks, sewage; Erosion of natural deposits

Turbidity

Turbidity (NTU) NA

TT=1TT=95% of

samples <0.3

0.08 0.05 0.08 2019 No Soil runoff

Total Organic Carbon

Total Organic Carbon (% Removal)Required removal

= 35-50%TT

Average % Removal

= 59.856 65 2019 No Naturally present in the environment

Unregulated Contaminant Monitoring (UCMR4)

Manganese (ppb) MNR 9.23 NA 2019EPA uses the Unregulated Contaminant Monitoring Rule (UCMR) to collect data for contaminants that are suspected to be present in drinking water and do not have health-based standards set under the Safe Drinking Water Act (SDWA).

Bromide MNR 58.8 NA 2019

TOC MNR 5.37 NA 2019

2 MPW 2019 Water Quality Report www.mountpleasantwaterworks.com

Constituent

Highest Level Detected in Your Water

EPA Lifetime Health Advisory

ADONA (ppt) ND No

GenX (ppt) ND No

Perfluorobutanesulfonic acid (PFBS) (ppt) 4.1 No

Perfluoroheptanoic acid (PFHpA) (ppt) 2.7 No

Perfluorohexanesulfonic acid (PFHxS) (ppt) 2.3 No

Perfluorohexanoic acid (PFHxA) (ppt) 6.3 No

Perfluorononanoic (PFNA) (ppt) ND No

Perfluorooctanesulfonic acid (PFOS) (ppt) 6.7 70

Perfluorooctanoic acid (PFOA) (ppt) 4.5 70

Voluntary Water Quality Monitoring

EPA SPECIAL NOTICE FOR IMMUNO-COMPROMISED PERSONSDrinking water, including bottled water, may reasonably be expected to contain at least small amounts of some constituents. The presence of constituents does not necessarily indicate that water poses a health risk. Some people may be more vulnerable to constituents 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/Centers for Disease Control (CDC) guidelines on appropriate means to lessen the risk of infection by Cryptosporidium and other microbial constituents are available from the Safe Water Drinking Hotline 800-426-4791.

EMERGING CONSTITUENTS PFOS/PFOA

Constituent MPW Treated Water Average EPA Secondary MCL

Chloride (ppm) 45 250

TDS (ppm) 230 500

Sodium (ppm) 69 NA

Alkalinity (ppm) 130 NA

Hardness (ppm) 45 NA

pH (S.U.) 8.5 NA

GENERAL INTEREST WATER QUALITY

Constituent MCLG ALYour

WaterSample

Date# Samples

Exceeding AL Exceeds AL Typical Source

Copper - action level at consumer taps (ppm) 1.3 1.3 0.13 2017 0 NoCorrosion of household plumbing systems; Erosion of natural deposits

Lead - action level at consumer taps (ppb) 0 15 2 2017 0 No

MPW water is free of lead and copper when it leaves the treatment plants. In keeping with the federal Safe Drinking Water Act and SCDHEC regulations, lead and copper tests are conducted annually from June – September. We are pleased to report that all results showed concentrations below EPA action levels, requiring no additional action. Our next sampling event will begin the summer of 2020.

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with customer service lines and home plumbing. MPW is responsible for providing high-quality drinking water but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at http://www.epa.gov/safewater/lead. To request a complimentary water test please contact us at 843-884-9626.

LEAD & COPPER WATER QUALITY MONITORING

For more information please contact: MPW Laboratory at 843-884-9626

MPW 2019 Water Quality Report 3www.mountpleasantwaterworks.com

How are Sources of Water Impacted?The sources for drinking water, both tap 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 can pick up substances resulting from the presence of animals or from human activity:

ABBREVIATIONS & DEFINITIONS ppm: parts per million, or milligrams per liter (mg/L)

ppb: parts per billion, or micrograms per liter (µg/L)

ppt: parts per trillion, or nanograms per liter (ng/L)

pCi/L: picocuries per liter (a measure of radioactivity)

% positive samples/month: Percent of samples taken monthly that were positive

NA: Not Applicable

ND: Not Detected

positive samples/yr: The number of positive samples taken that year

MCLG: Maximum Constituent Level Goal: The level of a constituent in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.

MCL: Maximum Constituent Level: The highest level of a constituent that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.

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

AL: Action Level: The concentration of a constituent which, if exceeded, triggers treatment or other requirements which a water system must follow.

MRDLG: Maximum Residual Disinfection Level Goal. The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial constituents.

MRDL: Maximum Residual Disinfectant Level. The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial constituents.

MNR: Monitored Not Regulated

Microbial Constituents such as viruses and bacteria, that may come from sewage treatment plants, septic systems, agricultural livestock operations, and wildlife.

Inorganic Constituents such as salts and metals, which 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 Constituents including synthetic and volatile organic chemicals, which are by-products of industrial processes and petroleum production, and can also come from gas stations, urban stormwater runoff, and septic systems.

Radioactive Constituents which can be naturally occurring or be the result of oil and gas production and mining activities.

4 MPW 2019 Water Quality Report www.mountpleasantwaterworks.com

An easy to way to understand your individual home water use is to look at your water bill—not just the amount due, but how much water you used. Less water going down the drain means more water available in the lakes, rivers and streams that we use for recreation and wildlife uses to survive. Using water more efficiently helps maintain supplies at safe levels, protecting human health and the environment.

24%Toilet

20%Shower

19%Faucet

12%Leaks

8%Other

17%WashingMachine

ARE YOU WATER WISE?WATER CONSERVATION MESSAGE

In the U.S., we are lucky to have easy access to some of the safest treated water in the world—just by turning on the tap. We wake up in the morning, take a shower, brush our teeth, grab a cup of coffee, and head out for the day. Water is an important part of our daily lives and we use it for a wide variety of purposes, but do we really understand how much we use for these everyday activities?

Outdoor water use account for approximately

and can be higher during periods of drought and in more water-intensive landscapes.

of household use30%

The average American family uses more than

of water per day at home. Roughly 70 percent of this use occurs indoors.

300 gallons

DID YOU KNOW?

How is MPW’s Groundwater Treated?

Withdraw from the Charleston Aquifer (2000 ft below the Earth’s surface)

Prefilter 1.0 micron to remove dirt, sand, rust, grit, and other suspended matter from water.

Reverse Osmosis Membranes A partially permeable membrane which removes pathogens, bacteria, ions, unwanted molecules and larger particles from drinking water.

Corrosion Control Calcium Chloride is added to adjust pH for optimum corrosion control and protect water pipes from leaching heavy metals.

Raw Water Blend 10% of our groundwater source is blended with RO treated water to naturally add fluoride and other beneficial minerals.

Disinfection Chlorine (sodium hypochlorite) and ammonia gas is added to the water to kill potential harmful organisms before the water leaves the plant. Chloramine maintains the disinfection in the water system.

Source: https://www.epa.gov/watersense

MPW 2019 Water Quality Report 5www.mountpleasantwaterworks.com

843-884-9626 • customerservice@mpwonline.com

1619 Rifle Range Road, Mount Pleasant, SC 29464

WE ALL HAVE SOMETHING AT STAKE WHEN IT COMES TO CLEAN WATER.

As a public water utility, your input is important to us. There are a variety of ways to get involved and learn more about the essential service we provide.

Expand your water IQ by following us on social media; joining us at our monthly Commission meetings; or registering to participate in our annual Citizens Academy program.

Citizens AcademyFall classes offered annually

Commission Meetings3rd Monday of the month

HOW CAN I GET MORE INVOLVED?