2019 Public Health Goals Reports of Compliance SCV Water Board - PowerPoint PPT Presentation

August 6, 2019 2019 Public Health Goals Reports of Compliance SCV Water Board Meeting

Public Water System Responsibilities • All water systems with >10,000 connections must: • Prepare a brief written report every 3 years • Hold a public meeting explaining the report • Compliance with Health and S afety Code, S ection 116470(b)

Purpose of Report • Provide information about levels of contaminants found in a drinking water supply that are above the Public Health Goals (PHG)

Public Health Goals (PHGs) • PHGs are non-enforceable, health-based goals established by the Office of Environmental Health Hazard Assessment (OEHHA) • Health risks based are set at the No Observable Adverse Effects Level (NOAEL) and are often theoretical with assumptions and mathematical extrapolations • Compliance with PHG levels is NOT required

Maximum Contaminant Levels (MCLs) • The highest level of a contaminant that is allowed in drinking water • MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration • MCLs are enforceable standards

Health Effects Based on MCLs • US EP A identified a lifetime “ reference risk range” of 1 in 10,000 to 1 in 1,000,000 • Maximum Contaminant Levels are set within this range • US EP A considers these levels to be safe and protective to human health

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 allow for a margin of safety and are non- enforceable public health goals

Other Definitions • AL = Action Level • BAT = Best Available Technology • DLR = Detection Limit for Reporting

Contents of the Report • List contaminants that have been detected above the PHG • List contaminants that have been detected above the MCLG where no PHG currently exists • Explain the potential health effects • Discuss the “ BAT” for bringing levels below the corresponding PHG or MCLG • Give a cost estimate for bringing levels below the corresponding PHG or MCLG

Santa Clarita Valley Water PHGs • Arsenic • Lead & Copper • Total Coliform • Radiolonuclides • Hexavalent Chromium

SCWD MCL vs. PHG for Arsenic 10 10 ppb 9 8 7 6 ppb 3.4 ppb 5 4 2 ppb 3 2 0.004 ppb 1 0 MCL PHG SCWD DLR

VWD MCL vs. PHG for Arsenic 10 10 ppb 9 8 7 6 ppb 5 3.5 ppb 4 2 ppb 3 0.004 ppb 2 1 0 MCL PHG VWD DLR

NWD MCL vs. PHG for Arsenic 10 10 ppb 9 8 7 6 ppb 5 3.3 ppb 4 <2 ppb <2 ppb 2 ppb 3 2 0.004 ppb 1 0 MCL PHG Castaic Newhall Pinetree DLR

Potential Health Effects: Arsenic • Exposure to arsenic over many years can cause cancer of the bladder, lungs, skin, kidneys, nasal passages, liver and prostate

BAT for Arsenic • Controls for arsenic include: • Reverse osmosis • Ion Exchange • Coagulation and filtration with ferric sulfate

SCWD AL vs. PHG for Lead 15 ppb 16 14 12 10 ppb 5.6 ppb 8 <5 ppb 5 ppb 6 4 0.2 ppb 2 0 AL PHG SCWD SCWD DLR (tap) (source)

VWD AL vs. PHG for Lead 16 15 ppb 14 12 10 ppb 8 <5 ppb 5 ppb 6 2.6 ppb 4 0.2 ppb 2 0 AL PHG VWD VWD DLR (tap) (source)

NWD AL vs. PHG for Lead 16 15 ppb 14 12 ppb 12 10 ppb 8 5.7 ppb <5 ppb <5 ppb 5 ppb <5 ppb 6 <5 ppb <5 ppb 4 2 0.2 ppb 0 AL PHG Castaic (tap) (source) Newhall (source) Pinetree Pinetree (source) Tesoro (tap) DLR Newhall Castaic (tap) (tap)

Potential Health Effects: Lead • Infants and children who drink water containing lead in excess of the AL could experience delays in their physical and mental development • Adults who drink water containing lead over many years could develop kidney problems, high blood pressure, and may be at an increased risk of getting cancer • DDW states that lead in the drinking water is rarely the cause of lead poisoning

SCWD AL vs. PHG for Copper 1400 1300 ppb 1200 1000 800 400 ppb ppb 600 300 ppb 400 <50 ppb 50 ppb 200 0 AL PHG SCWD SCWD DLR (tap) (source)

VWD AL vs. PHG for Copper 1400 1300 ppb 1200 1000 800 ppb 390 ppb 600 300 ppb 400 <50 ppb 50 ppb 200 0 AL PHG VWD VWD DLR (tap) (source)

NWD AL vs. PHG for Copper 1400 1300 ppb 1200 1000 800 500 ppb 510 ppb 600 300 ppb 340 ppb 220 ppb 400 50 ppb <50 ppb <50 ppb 200 <50 ppb 0 AL PHG Castaic (source) Newhall (source) Pinetree Pinetree (source) Tesoro DLR Newhall Castaic (tap) (tap) (tap) (tap)

Potential Health Effects: Copper • Copper is an essential nutrient required by humans • People who drink water with very high amounts of copper could experience intestinal upset, liver damage or kidney damage

BAT for Lead and Copper • Corrosion Control Treatment • S CV Water supplies water characterized as: • Non-aggressive • Non-corrosive • S CV Water has “ optimized corrosion control” as determined by DDW

Total Coliform • Group of bacteria which are naturally present in the environment • Commonly found in soil and plant material • Usually not harmful • Good indicator for the potential presence of pathogens • If total coliforms are present, must test for E. coli

SCWD MCL vs. MCLG for Total Coliform 5.0% 5.0% 4.5% 4.0% 3.5% 3.0% ppb 1.6% 2.5% 2.0% 1.5% 0% 1.0% 0.5% 0.0% MCL MCLG SCWD

VWD MCL vs. MCLG for Total Coliform 5.0% 5.0% 4.5% 4.0% 3.5% 3.0% ppb 2.5% 2.0% 0.9% 1.5% 1.0% 0% 0.5% 0.0% MCL MCLG VWD

Potential Health Effects: Total Coliform • Usually not harmful • Pathogens associated with TC can cause: • Diarrhea • Cramps • Nausea • Headaches • Fatigue

Controlling Total Coliforms • Placement & construction of wells • Disinfection of groundwater • Maintaining disinfectant residual in distribution system • Maintenance of distribution system

SCWD MCL vs. PHG for Radionuclides 30 Gross Alpha 25 Uranium 20 pCi/L 20 15 pCi/L pCi/L 15 7.4 8.6 pCi/L pCi/L 10 0 pCi/L Gross Alpha/ 3 pCi/L 1 pCi/L Uranium 5 0.43 pCi/L 0 pCi/L 0 MCL MCLG PHG SCWD DLR

VWD MCL vs. PHG for Radionuclides 30 Gross Alpha 25 Uranium 20 pCi/L 20 15.0 pCi/L pCi/L 15 9.5 5.3 pCi/L pCi/L 10 0 pCi/L 1 pCi/L 0.43 p Ci/L Gross Alpha/ 3 pCi/L 5 Uranium 0 pCi/L 0 MCL MCLG PHG VWD DLR

NWD MCL vs. PHG for Radionuclides 30 Gross Alpha 25 Uranium 20 pCi/L 20 15.0 pCi/L pCi/L 15 9.1 pCi/L 10 0 pCi/L 0.43 pCi/L Gross Alpha/ 1 pCi/L 3 pCi/L 5 Uranium <3 0 pCi/L pCi/L 0 MCL MCLG PHG Pinetree DLR

Potential Health Effects: Radionuclides • S ome people who drink water containing alpha/ beta emitters or uranium in excess of the MCL over many years may have an increased risk of getting cancer

BAT for Radionuclides • Controls for Radionuclides include: • Ion exchange • Reverse osmosis

VWD MCL vs. PHG for Hexavalent Chromium 10 ppb 10 8 6 ppb 2.0 ppb 4 0.02 ppb 2 1 ppb 0 MCL PHG VWD DLR

NWD MCL vs. PHG for Hexavalent Chromium 10 10 ppb 8 6 ppb 4 <1 ppb 1.3 ppb <1 ppb 0.02 ppb 1 ppb 2 0 MCL PHG Castaic Pinetree Newhall DLR

Potential Health Effects: Hexavalent Chromium • Hexavalent Chromium is a potent carcinogen when inhaled • Found to cause cancer in rats and mice that were exposed through drinking water

BAT for Hexavalent Chromium • Controls for Hexavalent Chromium include: • Ion exchange • Coagulat ion/ filt rat ion • Reverse osmosis • Lime soft ening

Thank you! Questions?