Safe Drinking Water Regulations Tool

INORGANIC CHEMICALS (IOCs)

Antimony

  • MCL/MCLG (mg/L unless noted): 0.006 / 0.006
  • Health Effects: Increase in blood cholesterol; decrease in blood sugar
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Asbestos (fiber length > 10 micrometers)

  • MCL/MCLG (mg/L unless noted): 7 MFL/7MFL
  • Health Effects: Increased risk of developing benign intestinal polyps
  • Monitoring Requirements/Comments: Once every nine years.

Barium

  • MCL/MCLG (mg/L unless noted): 2/2
  • Health Effects: Increase in blood pressure
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Beryllium

  • MCL/MCLG (mg/L unless noted): 0.004/0.004
  • Health Effects: Intestinal lesions
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Cadmium

  • MCL/MCLG (mg/L unless noted): 0.005/0.005
  • Health Effects: Kidney damage
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Chromium (total)

  • MCL/MCLG (mg/L unless noted): 0.1/0.1
  • Health Effects: Allergic dermatitis
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Copper (revisions & clarifications)

  • MCL/MCLG (mg/L unless noted): TT (AL = 1.3) / 1.3
  • Health Effects: Gastrointestinal/liver/kidney problems
  • Monitoring Requirements/Comments: Copper: Same as Lead.

Cyanide (as free cyanide)

  • MCL/MCLG (mg/L unless noted): 0.2/0.2
  • Health Effects: Thyroid/neurological effects
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Fluoride

  • MCL/MCLG (mg/L unless noted): 4.0/4.0
  • Health Effects: Bone disease: Children may get mottled teeth
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Lead (revisions & clarifications)

  • MCL/MCLG (mg/L unless noted): TT (AL = 0.015) / 0
  • Health Effects: Kidney problems; high blood pressure; infants and children - delays in physical or mental development
  • Monitoring Requirements/Comments: Sample taken at the kitchen or bathroom sink tap. ALs must be met in 90% of the samples. Follow-up monitoring every 6 months after corrosion controls initiated or optimized. Reduced monitoring for systems consistently meeting AL. An AL exceedance can trigger water quality parameter monitoring, corrosion control treatment, source water monitoring/treatment, and lead service line replacement. Systems exceeding Lead AL must provide public notification to affected populations.

Mercury (inorganic)

  • MCL/MCLG (mg/L unless noted): 0.002/0.002
  • Health Effects: Kidney damage
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Nitrate (as N)

  • MCL/MCLG (mg/L unless noted): 10/10
  • Health Effects: Methemoglobinemia (blue baby syndrome)/diuresis
  • Monitoring Requirements/Comments: Ground water annually; surface water quarterly initially, then annually.

Nitrite (as N)

  • MCL/MCLG (mg/L unless noted): 1/1
  • Health Effects: Methemoglobinemia (blue baby syndrome)/diuresis
  • Monitoring Requirements/Comments: One sample during first 3-year compliance period. Repeat frequency determined by primacy agency.

Selenium

  • MCL/MCLG (mg/L unless noted): 0.05/0.05
  • Health Effects: Hair or fingernail loss; numbness of fingers or toes; circulatory problems
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Thallium

  • MCL/MCLG (mg/L unless noted): 0.002/0.0005
  • Health Effects: Hair loss; changes in blood; kidney/liver/intestinal problems
  • Monitoring Requirements/Comments: For IOCs: Once a year for surface water. Once every 3 years for ground water (not including Asbestos, Lead and Copper, Nitrate, Nitrite and Radionuclides). Minimize monitoring costs by using historical data, waivers, susceptibility waivers, and/or making composite samples.

Arsenic

  • MCL/MCLG (mg/L unless noted): 0.010/0
  • Health Effects: Cancer risk; cardiovascular and dermal problems
  • Monitoring Requirements/Comments: Same as IOCs. Applies to CWS and NTNCWS.

Radionuclides: Combined Radium-226 and Radium-228

  • MCL/MCLG (mg/L unless noted): 5 pCi/L / 0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: Sample point is the distribution system entry point that is representative of all sources being used. Four consecutive quarterly samples must be taken at all sample points. Rule applies to Community Water Systems only.

Radionuclides: Gross Alpha (excluding radon and uranium)

  • MCL/MCLG (mg/L unless noted): 15 pCi/L / 0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: Sample point is the distribution system entry point that is representative of all sources being used. Four consecutive quarterly samples must be taken at all sample points. Rule applies to Community Water Systems only.

Radionuclides: Beta Particles and Photon Emitters

  • MCL/MCLG (mg/L unless noted): 4 mrem/year / 0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: Primacy agency must designate vulnerable systems. Once deemed vulnerable, quarterly samples required for beta emitters and annual samples for Tritium and Strontium-90 at entry to distribution system. Compliance is based on the running annual average of four quarterly samples taken at each sample point.

Radionuclides: Uranium

  • MCL/MCLG (mg/L unless noted): 0.030/0
  • Health Effects: Kidney problems; cancer risk
  • Monitoring Requirements/Comments: Same as Combined Radium and Gross Alpha.

ORGANIC CHEMICALS
Synthetic Organic Chemicals (SOCs)

2,3,7,8-TCDD (Dioxin)

  • MCL/MCLG (mg/L unless noted): 0.00000003/0
  • Health Effects: Cancer risk; reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

2,4,5-TP (Silvex)

  • MCL/MCLG (mg/L unless noted): 0.05/0.05
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

2,4-D

  • MCL/MCLG (mg/L unless noted): 0.07/0.07
  • Health Effects: Adrenal gland/liver/kidney problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Acrylamide

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Cancer risk; nervous system/blood problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Alachlor

  • MCL/MCLG (mg/L unless noted): 0.002/0
  • Health Effects: Cancer risk; eye/liver/kidney/spleen problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Atrazine

  • MCL/MCLG (mg/L unless noted): 0.003/0.003
  • Health Effects: Cardio problems/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Benzo(a)pyrene (PAHs)

  • MCL/MCLG (mg/L unless noted): 0.0002/0
  • Health Effects: Cancer risk; reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Carbofuran

  • MCL/MCLG (mg/L unless noted): 0.04/0.04
  • Health Effects: Blood/nervous/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Chlordane

  • MCL/MCLG (mg/L unless noted): 0.002/0
  • Health Effects: Cancer risk; liver/nervous system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Dalapon

  • MCL/MCLG (mg/L unless noted): 0.2/0.2
  • Health Effects: Kidney problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Di(2-ethylhexyl) adipate

  • MCL/MCLG (mg/L unless noted): 0.4/0.4
  • Health Effects: Liver/weight loss/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,2- Dibromo-3-chloropropane (DBCP)

  • MCL/MCLG (mg/L unless noted): 0.0002/0
  • Health Effects: Cancer risk; reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Di(2-ethylhexyl) phthalate (DEHP)

  • MCL/MCLG (mg/L unless noted): 0.006/0
  • Health Effects: Cancer risk; liver/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Dinoseb

  • MCL/MCLG (mg/L unless noted): 0.007/0.007
  • Health Effects: Reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Diquat

  • MCL/MCLG (mg/L unless noted): 0.02/0.02
  • Health Effects: Ocular problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Endothall

  • MCL/MCLG (mg/L unless noted): 0.1/0.1
  • Health Effects: Stomach/intestinal problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Endrin

  • MCL/MCLG (mg/L unless noted): 0.002/0.002
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Epichlorohydrin

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Cancer risk; stomach problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Ethylene Dibromide (EDB)

  • MCL/MCLG (mg/L unless noted): 0.00005/0
  • Health Effects: Cancer risk; liver/kidney/stomach/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Glyphosate

  • MCL/MCLG (mg/L unless noted): 0.7/0.7
  • Health Effects: Kidney/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Heptachlor

  • MCL/MCLG (mg/L unless noted): 0.0004/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Heptachlor Epoxide

  • MCL/MCLG (mg/L unless noted): 0.0002/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Hexachlorobenzene

  • MCL/MCLG (mg/L unless noted): 0.001/0
  • Health Effects: Cancer risk; liver/reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Hexachlorocyclopentadiene (HEX)

  • MCL/MCLG (mg/L unless noted): 0.05/0.05
  • Health Effects: Kidney/stomach problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Lindane

  • MCL/MCLG (mg/L unless noted): 0.0002/0.0002
  • Health Effects: Kidney/liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Methoxychlor

  • MCL/MCLG (mg/L unless noted): 0.04/0.04
  • Health Effects: Reproductive system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Oxamyl (Vydate)

  • MCL/MCLG (mg/L unless noted): 0.2/0.2
  • Health Effects: Nervous system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Polychlorinated Biphenyls (PCBs)

  • MCL/MCLG (mg/L unless noted): 0.0005/0
  • Health Effects: Cancer risk; thymus gland/immune deficiencies/reproductive or nervous system problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Pentachlorophenol

  • MCL/MCLG (mg/L unless noted): 0.001/0
  • Health Effects: Cancer risk; liver/kidney problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Picloram

  • MCL/MCLG (mg/L unless noted): 0.5/0.5
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Simazine

  • MCL/MCLG (mg/L unless noted): 0.004/0.004
  • Health Effects: Problems with blood
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Toxaphene

  • MCL/MCLG (mg/L unless noted): 0.003/0
  • Health Effects: Cancer risk; liver/kidney/thyroid problems
  • Monitoring Requirements/Comments: For SOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Volatile Organic Chemicals (VOCs)

1,1,1-Trichloroethane

  • MCL/MCLG (mg/L unless noted): 0.2/0.20
  • Health Effects: Liver/circulatory/nervous system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,1,2-Trichloroethane

  • MCL/MCLG (mg/L unless noted): 0.005/0.003
  • Health Effects: Kidney/liver/immune system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,1-Dichloroethylene

  • MCL/MCLG (mg/L unless noted): 0.007/0.007
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,2,4-Trichlorobenzene

  • MCL/MCLG (mg/L unless noted): 0.07/0.07
  • Health Effects: Adrenal gland problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,2-Dichloroethane

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

1,2-Dichloropropane

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Benzene

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk; anemia/blood problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Carbon Tetrachloride

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Chlorobenzene

  • MCL/MCLG (mg/L unless noted): 0.1/0.1
  • Health Effects: Kidney/liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Cis-1,2-Dichloroethylene

  • MCL/MCLG (mg/L unless noted): 0.07/0.07
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Dichloromethane

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Ethylbenzene

  • MCL/MCLG (mg/L unless noted): 0.7/0.7
  • Health Effects: Kidney/liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Ortho-Dichlorobenzene

  • MCL/MCLG (mg/L unless noted): 0.6/0.6
  • Health Effects: Kidney/liver/circulatory system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Para-Dichlorobenzene

  • MCL/MCLG (mg/L unless noted): 0.075/0.075
  • Health Effects: Kidney/liver/spleen/circulatory system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Styrene

  • MCL/MCLG (mg/L unless noted): 0.1/0.1
  • Health Effects: Liver/kidney/circulatory system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Tetrachloroethylene (PCE)

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Toluene

  • MCL/MCLG (mg/L unless noted): 1/1
  • Health Effects: Kidney/liver/nervous system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Trans-1,2-Dichloroethylene

  • MCL/MCLG (mg/L unless noted): 0.1/0.1
  • Health Effects: Liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Trichloroethylene (TCE)

  • MCL/MCLG (mg/L unless noted): 0.005/0
  • Health Effects: Cancer risk; liver problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Vinyl Chloride

  • MCL/MCLG (mg/L unless noted): 0.002/0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

Xylenes (total)

  • MCL/MCLG (mg/L unless noted): 10/10
  • Health Effects: Nervous system problems
  • Monitoring Requirements/Comments: For VOCs: Four consecutive quarterly samples during first compliance period. Compliance is based on annual average of quarterly samples. If no detections are found during initial round, two quarterly samples are required each year for systems serving > 3,300; one sample is required every 3 years for smaller systems. With the completion of source water assessments, primacy agencies are allowed to develop alternative monitoring requirements. Contact your local primacy agency for further information. Applies to CWS and NTNCWS.

DISINFECTANTS and DISINFECTION BYPRODUCTS

Stage 1 D/DBPR Disinfectants

  • Monitoring Requirements/Comments: Applies to all CWS and NTNCWS that treat water with a chemical disinfectant for primary or residual treatment

Chlorine (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): 4.0 (as Cl2) MRDL/4 MRDLG
  • Health Effects: Eye/nose irritation; stomach discomfort
  • Monitoring Requirements/Comments: Monitor at the same sample locations as the TCR. Compliance based on running annual arithmetic average of monthly averages. Daily sample at distribution system entry point

Chloramines (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): 4.0 (as Cl2) MRDL/4 MRDLG
  • Health Effects: Eye/nose irritation; stomach discomfort; anemia
  • Monitoring Requirements/Comments: Monitor at the same sample locations as the TCR. Compliance based on running annual arithmetic average of monthly averages. Daily sample at distribution system entry point

Chlorine Dioxide (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): 0.8 (as ClO2) MRDL / 0.8 MRDLG
  • Health Effects: Anemia; nervous system problems
  • Monitoring Requirements/Comments: Daily sample at distribution system entry points. Four quarterly distribution system samples. Compliance based on running annual average of quarterly average

Total Trihalomethanes - TTHMs (Stage 1 and Stage 2 D/DBPR)

  • MCL/MCLG (mg/L unless noted): MCL: TTHMs 0.080 / MCLG: Chloroform (0.07), BDCM (0), Bromoform (0), DBCM (0.06)
  • Health Effects: Cancer risk; potential reproductive system effects; liver/kidney/nervous system problems
  • Monitoring Requirements/Comments: Compliance Monitoring: Locational Running Annual Average (LRAA) of quarterly samples (yearly for very small surface water and small ground water systems) taken at locations determined by Initial Distribution System Evaluation (IDSE). Compliance sites are locations in the distribution system where TTHMs are high, HAA5s are high, and at average detention time sites. The number of sites is based on the type of source water and population served

Haloacetic Acids - HAA5 (Stage 1 and Stage 2 D/DBPR)

  • MCL/MCLG (mg/L unless noted): MCL: HAA5 0.060 / MCLG: MCAA (0.07), DCAA (0), TCAA (0.02)
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: Compliance Monitoring: Locational Running Annual Average (LRAA) of quarterly samples (yearly for very small surface water and small ground water systems) taken at locations determined by Initial Distribution System Evaluation (IDSE). Compliance sites are locations in the distribution system where TTHMs are high, HAA5s are high, and at average detention time sites. The number of sites is based on the type of source water and population served

Chlorite (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): 1.0/0.8
  • Health Effects: Anemia; nervous system problems
  • Monitoring Requirements/Comments: Systems that add chlorine dioxide required to take daily sample at distribution system entry point

Bromate (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): 0.010/0
  • Health Effects: Cancer risk
  • Monitoring Requirements/Comments: One sample per month (ozone systems only). Compliance based on running annual average

Total Organic Carbon - TOC (Stage 1 D/DBPR)

  • MCL/MCLG (mg/L unless noted): TT
  • Monitoring Requirements/Comments: Source and treated water TOC sampled once a month. Compliance based on running annual average of TOC removal ratios

MICROBIOLOGICAL CONTAMINANTS

Total Coliforms (Total Coliform Rule and Revised Total Coliform Rule)

  • MCL/MCLG (mg/L unless noted): MCL = Treatment Technique (see comments). MCLG = 0
  • Health Effects: Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful bacteria may be present or that a potential pathway exists through which contamination may enter the drinking water distribution system. The presence of E.coli may indicate potential contamination that can cause diarrhea, cramps, nausea, headaches or other symptoms.
  • Monitoring Requirements/Comments: Applies to all surface water and ground water systems. The total number and location of samples is based on the population served and a system-specific sampling plan. If 40 samples or more/month, no more than 5.0% positive; < 40 samples/month, no more than one positive for total coliforms. RTCR is effective April 1, 2016. Applies to Community and Non-Community Water Systems. The RTCR specifies frequency and timing of microbial testing based on the population served and a system-specific sampling plan for total coliform. Systems must conduct assessment (Level 1 or 2) based on treatment technique triggers. Level 1 TT triggers: a) if taking 40 or more samples per month, system exceeds 5.0% total coliform-positive samples; (b) if taking fewer than 40 samples per month, system has 2 or more total coliform-positive samples. Level 2 TT triggers: a) E.coli MCL violation; b) second Level 1 trigger in rolling 12 months; c) Level 1 trigger in 2 consecutive years. Acute violations are based on a positive E. coli (Tier 1 Public Notification) when a repeat sample is E.coli+ following Total Coliform positive (TC+) routine sample; a repeat sample is TC+ following E.coli+ routine sample; a system fails to take required repeat samples following an E.coli+ routine sample; or a system fails to test for E.coli when any repeat sample is TC+. Systems must measure disinfectant residual at least at same location and time as total coliform samples are sampled.

Fecal Coliforms (Total Coliform Rule)

  • MCL/MCLG (mg/L unless noted): MCL is no longer relevant after Revised Total Coliform Rule goes into effect in April 2016.  MCLG = 0
  • Health Effects: Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful bacteria may be present or that a potential pathway exists through which contamination may enter the drinking water distribution system. The presence of E.coli may indicate potential contamination that can cause diarrhea, cramps, nausea, headaches or other symptoms.
  • Monitoring Requirements/Comments: Applies to all surface water and ground water systems. The total number and location of samples is based on the population served and a system-specific sampling plan. If 40 samples or more/month, no more than 5.0% positive; < 40 samples/month, no more than one positive for total coliforms.

E.coli (Total Coliform Rule and Revised Total Coliform Rule)

  • MCL/MCLG (mg/L unless noted): MCL = Treatment Technique (see comments). MCLG = 0
  • Health Effects: Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful bacteria may be present or that a potential pathway exists through which contamination may enterthe drinking water distribution system. The presence of E.coli may indicate potential contamination that can cause diarrhea, cramps, nausea, headaches or other symptoms.
  • Monitoring Requirements/Comments: RTCR is effective April 1, 2016. Applies to Community and Non-Community Water Systems. The RTCR specifies frequency and timing of microbial testing based on the population served and a system-specific sampling plan for total coliform. Systems must conduct assessment (Level 1 or 2) based on treatment technique triggers. Level 1 TT triggers: a) if taking 40 or more samples per month, system exceeds 5.0% total coliform-positive samples; (b) if taking fewer than 40 samples per month, system has 2 or more total coliform-positive samples. Level 2 TT triggers: a) E.coli MCL violation; b) second Level 1 trigger in rolling 12 months; c) Level 1 trigger in 2 consecutive years. Acute violations are based on a positive E. coli (Tier 1 Public Notification) when a repeat sample is E.coli+ following Total Coliform positive (TC+) routine sample; a repeat sample is TC+ following E.coli+ routine sample; a system fails to take required repeat samples following an E.coli+ routine sample; or a system fails to test for E.coli when any repeat sample is TC+. Systems must measure disinfectant residual at least at same location and time as total coliform samples are sampled.

Turbidity (Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT
  • Health Effects: None. Interferes with disinfection.
  • Monitoring Requirements/Comments: Applies to all public water systems using surface water or ground water under the direct influence of surface water. Grab samples every four hours or continuous monitoring for turbidity. Continuous chlorine residual required for systems > 3,300; One to four grab samples per day are allowed for systems ≤ 3,300. Must maintain disinfectant residual ≥ 0.2 mg/L entering the distribution system. Performance requirements demonstrated through combination of removal via filtration and inactivation via disinfection. See IESWTR and LT1ESWTR for turbidity TT requirements.

Giardia lamblia (Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Gastrointestinal illness; Giardiasis
  • Monitoring Requirements/Comments: Minimum three-log removal/inactivation of Giardia (99.9%).

Enteric Viruses (Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Gastrointestinal and other viral infections
  • Monitoring Requirements/Comments: Minimum four-log removal/inactivation of viruses (99.99%).

Legionella (Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Legionnaire's disease
  • Monitoring Requirements/Comments: No limit. Rule assumes if virus & Giardia limits are met, Legionella will be controlled.

Heterotrophic Plate Count - HPC (Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: None. Used to measure variety of bacteria common in water.
  • Monitoring Requirements/Comments: Filtration avoidance is allowed under certain circumstances (see Regulation). Lower bacteria concentration indicates better maintained water system.

Turbidity (Interim Enhanced Surface Water Treatment Rule and Long-Term 1 Enhanced Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT
  • Health Effects: None. Interferes with disinfection.
  • Monitoring Requirements/Comments: Applies to all public water systems using surface water or ground water under the direct influence of surface water. Must continue to comply with SWTR. Treatment effectiveness is demonstrated by combined effluent turbidity ≤ 0.3 NTU in 95% of measurements taken each month. Conventional and direct filtration systems must measure combined filter effluent turbidity at least every four hours and continuously monitor turbidity of each individual filter. The maximum turbidity limit is 1 NTU. If the PWS meets filtered water turbidity criteria, it is assumed to achieve the required 2-log Cryptosporidium removal. Performance triggers for individual filter turbidities lead to additional reporting and assessments if exceeded. IESWTR applies to systems = 10,000; LT1ESWTR applies to systems <10,000 people.

Cryptosporidium (Interim Enhanced Surface Water Treatment Rule and Long-Term 1 Enhanced Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Gastrointestinal illness; Cryptosporidiosis
  • Monitoring Requirements/Comments: Applies to all public water systems using surface water or ground water under the direct influence of surface water. Must continue to comply with SWTR. Treatment effectiveness is demonstrated by combined effluent turbidity ≤0.3 NTU in 95% of measurements taken each month. Conventional and direct filtration systems must measure combined filter effluent turbidity at least every four hours and continuously monitor turbidity of each individual filter. The maximum turbidity limit is 1 NTU. If the PWS meets filtered water turbidity criteria, it is assumed to achieve the required 2-log Cryptosporidium removal. Performance triggers for individual filter turbidities lead to additional reporting and assessments if exceeded. IESWTR applies to systems = 10,000; LT1ESWTR applies to systems ≥10,000 people.

Cryptosporidium (Long Term 2 Enhanced Surface Water Treatment Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Gastrointestinal illness; Cryptosporidiosis
  • Monitoring Requirements/Comments: Applies to all public water systems using surface water or ground water under the direct influence of surface water. Monthly monitoring for Cryptosporidium for 2 years is required to characterize the source water. Small systems monitor for E.coli in lieu of Cryptosporidium, unless E.coli is high - then monitor for Cryptosporidium. First round of monitoring complete by 2010. Second round of Cryptosporidium monitoring due 2015-2019, depending on system size. Calculated Cryptosporidium concentration defines required level of additional treatment. Treatment bins differ for filtered and unfiltered systems.Additional treatment options selected from the Microbial Toolbox.

Cryptosporidium (Filter Backwash Rule)

  • MCL/MCLG (mg/L unless noted): TT/0
  • Health Effects: Gastrointestinal illness; Cryptosporidiosis
  • Monitoring Requirements/Comments: No monitoring is required, but systems must collect and retain information on recycle flows for review by the primacy agency. Applies to all systems using conventional or direct filtration treatment that recycle spent filter backwash water (excluding membrane plants), thickener supernatant or liquids from dewatering processes. TT Requirement - All recycle flows must be returned at the head of the plant so that complete treatment of the recycle stream is provided. Treatment of recycle streams prior to recycle is not required..

Viruses (Ground Water Rule)

  • MCL/MCLG (mg/L unless noted): TT
  • Health Effects: Gastrointestinal illness
  • Monitoring Requirements/Comments: Applies to all ground water systems. Sanitary surveys required every 3 years for CWS and every 5 years for NCWS. Source water monitoring is required for systems that do not treat to 4-log viral inactivation and is triggered by a total coliform (TC)-positive sample in the distribution system. Samples must be taken within 24 hours of TC-positive at all sources on line at the time the TC sample was taken. Special notification requirements for wholesalers and consecutive systems for TC-positive. If your primacy agency identifies significant deficiencies in sanitary survey, corrective action is required and can consist of: correcting deficiencies, providing alternative source of water, eliminating source of contamination or providing treatment for 4-log inactivation of viruses.

ADDITIONAL RULES

Consumer Confidence Report Rule (CCR)

  • MCL/MCLG (mg/L unless noted): None (data reporting only)
  • Monitoring Requirements/Comments: PWS to prepare and distribute annual CCR to their customers every July.

FUTURE REGULATIONS

Strontium

  • Description: Preliminary positive determination to regulate from the Third Contaminant Candidate List (CCL3). Final determination to regulate will be made in 2015 or 2016, then the rule proposal will be written.
  • Expected Dates for Proposed and Final Rules: Proposal in 2018; Final in 2019

Perchlorate

  • Description: Modeling research must be completed to understand impacts to infants before moving forward with rule.
  • Expected Dates for Proposed and Final Rules: Proposal in 2015; Final in 2018 or 2019

Long-Term Lead and Copper Rule (LT-LCR) Revisions

  • Description: Still need to resolve complex issues related to replacement of lead service lines.
  • Expected Dates for Proposed and Final Rules: Proposal in 2016 or 2017; Final in 2018 or 2019

Carcinogenic VOCs (cVOCs)

  • Description: Decisions still required regarding which contaminants to include and the basis for defining the group (similar analytics or similar treatment).
  • Expected Dates for Proposed and Final Rules: Proposal in 2015 or 2016; Final in 2017 or 2018

Hexavalent Chromium

  • Description: Updated risk assessment is incomplete but required to move forward with a rule. Could be addressed in the Third Six-Year review of existing rules with a revision to the total chromium regulation.
  • Expected Dates for Proposed and Final Rules: Third Six-Year Review in 2016. Proposal in 2017 or 2018; Final in 2019 or 2020

Nitrosamines

  • Description: Was not given a positive preliminary determination from the CCL3, but could be picked up under the Third Six-Year review of all regulations along with all DBPs. This review should be complete by the end of 2015. Nitrosamines in drinking water are a relatively small part of overall exposure and total risk, so justification of a rule may be difficult.
  • Expected Dates for Proposed and Final Rules: Third Six-Year Review in 2016. Proposal in 2017 or 2018; Final in 2019 or 2020

Chlorate

  • Description: Was not given a positive preliminary determination from the CCL3, but could be picked up under the Third Six-Year review of all regulations along with all DBPs. This review should be complete by the end of 2015.
  • Expected Dates for Proposed and Final Rules: Third Six-Year Review in 2016. Proposal in 2017 or 2018; Final in 2019 or 2020

SECONDARY DRINKING WATER STANDARDS

Aluminum (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 0.05 to 0.2
  • Noticeable Effects Above Secondary MCL: Colored water

Chloride (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 250
  • Noticeable Effects Above Secondary MCL: Salty taste

Color (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 15 (color units)
  • Noticeable Effects Above Secondary MCL: Visible tint

Copper (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 1
  • Noticeable Effects Above Secondary MCL: Metallic taste; blue-green staining

Corrosivity (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): Noncorrosive
  • Noticeable Effects Above Secondary MCL: Metallic taste; corroded pipes/ fixtures; staining

Fluoride (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 2.0
  • Noticeable Effects Above Secondary MCL: Tooth discoloration
  • Recommended Level: US Department of Health and Human Services has revised the recommended fluoride level in drinking water to 0.7 mg/L.

Foaming Agents (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 0.5
  • Noticeable Effects Above Secondary MCL: Frothy, cloudy; bitter taste; odor

Iron (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 0.3
  • Noticeable Effects Above Secondary MCL: Rusty color; sediment; metallic taste; reddish or orange staining

Manganese (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 0.05
  • Noticeable Effects Above Secondary MCL: Black to brown color; black staining; bitter metallic taste

Odor (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 3 TON (threshold odor number)
  • Noticeable Effects Above Secondary MCL: "Rotten-egg", musty, dusty or chemical smell

pH (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 6.5 - 8.5 su
  • Noticeable Effects Above Secondary MCL: Low pH: bitter metallic taste; corrosion. High pH: slippery feel; soda taste; deposits 

Silver (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 0.10
  • Noticeable Effects Above Secondary MCL: Skin discoloration; graying of the white part of the eye

Sulfate (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 250
  • Noticeable Effects Above Secondary MCL: Salty taste

Total Dissolved Solids (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 500
  • Noticeable Effects Above Secondary MCL: Hardness; deposits; colored water; staining; salty taste

Zinc (Secondary Drinking Water Standards)

  • Guidelines: National Secondary Drinking Water Standards are non-enforceable guidelines regulating contaminants that may cause cosmetic effects or aesthetic effects in drinking water. The EPA recommends secondary standards but does not require systems to comply with secondary MCLs. States may establish or enforce standards that differ from these recommendations.
  • Secondary MCL (mg/L unless noted): 5
  • Noticeable Effects Above Secondary MCL: Metallic taste