1. Basic Ground Water Treatment
Cindy Sek
Sanitary Engineer 2
DPH - Drinking Water Section
Compliance Regions - North

2. Topics of Discussion Why is water treatment used? ANSI/NSF Standards
Considerations before installing treatment
Disinfection
Organics removal
Iron and manganese removal
Corrosion control treatment
Treatment systems in combination
General Water Treatment Guidelines
Classification of Water Treatment Plants

3. Why is Water Treatment Used?
To remove contaminants and achieve compliance with a Maximum Contaminant Level (MCL) thereby reducing health risk
Disinfection to kill or inactivate total coliform and/or E.coli bacteria and associated microbial pathogens
Organics removal with Granular Activated Carbon (GAC)

4. Why is Water Treatment Used?
To achieve aesthetic water quality standards
Sediment filters to remove suspended particles
Ion exchange water softener
Iron and manganese filtration
Taste and odor control using Granular Activated Carbon (GAC)

5. Why is Water Treatment Used?
For corrosion control
Calcite filtration for pH adjustment
Chemical injection for pH adjustment
Orthophosphate for sequestering

6. ANSI/NSF Standard 60 & 61
All drinking water treatment chemicals and components must be certified to ANSI/NSF standards.
NSF/ANSI Standard 60: Drinking Water Treatment Chemicals - Health Effects is the nationally recognized health effects standard for chemicals which are used to treat drinking water.
NSF/ANSI Standard 61: Drinking Water System Components - Health Effects is the nationally recognized health effects standard for all devices, components and materials which contact drinking water.

7. Other ANSI/NSF Standards
NSF/ANSI Standard 42: Drinking Water Treatment Units - Aesthetic Effects
NSF/ANSI Standard 44: Cation Exchange Water Softeners
NSF/ANSI Standard 53: Drinking Water Treatment Units - Health Effects
NSF/ANSI Standard 55: Ultraviolet Microbiological Water Treatment Systems
NSF/ANSI Standard 58: Reverse Osmosis Drinking Water Treatment Systems
Visit for more information

8. Considerations Before Installing Treatment
Type and concentration(s) of contaminant(s)
Treatment options
NSF Certification
Initial cost of installing treatment equipment and ongoing costs of maintenance, chemicals, and additional water quality testing
Available room to install treatment in existing pump house
Submittal to DPH for review and approval prior to installation per RCSA Section B102(d)(2)
Water treatment plant operator to maintain and operate the treatment system
Staff certified at the appropriate level
Contracting with a certified treatment plant operator

9. Chemical Disinfection
Chlorination is used to inactivate bacteria and/or viruses that may be introduced into the water system
Correct well violations and deficiencies first
Eliminate cross connections within system piping first
Use alternate source of supply
GWR requires maintaining 4-log virus treatment
Source with significant deficiency or fecal contamination
Exempt from GWR source water monitoring requirement
Existing treatment systems need to demonstrate that treatment meets this level
A CT value of about 6 is necessary to achieve this level
Routine compliance monitoring is required to ensure that treatment is effective and public health is protected.

10. Compliance Monitoring
Chlorine Compliance monitoring
>3,300 population – continuous monitoring at a location at least equivalent to 1st customer.
<3,300 population – continuous monitoring at a location equivalent to 1st customer or 1 grab sample/day at the time of peak hourly flow.

11. http://www. epa. gov/safewater/disinfection/gwr/compliancehelp
under GWR Contact Time (CT) Calculator

12. Treatment
EPA CT Value Table

13. Chemical Injection Systems
4-log treatment systems must have must have redundancy or backup equipment immediately available
4-log treatment systems must have redundancy
or backup equipment immediately available.

14. Chlorination Systems Advantages
Destroy bacteria, viruses, and other pathogenic microorganism, except Giardia and Cryptosporidium
Provide a barrier of protection throughout the water system when an adequate chlorine residual is maintained
Disinfectant residual can be monitored
Can be used as an oxidant to suspend metals in solution for better filtration treatment performance
Oxidizes hydrogen sulfide to reduce nuisance odor

15. Chlorination Systems Disadvantages More maintenance
Chemical addition and disinfection by-products
Need to maintain adequate contact time for effective disinfection
Need to monitored on a daily basis
Requires a higher certified operator skill level
More space required for contact tank and treatment system
Mineral oxidation may necessitate the need to install filtration treatment if raw water has mineral content.
Iron and/or Manganese common in groundwater

16. Trivia Questions
The GWR requires what level of treatment at the entry point for effective virus inactivation / removal?
4-log
Can I continue to use my existing disinfection treatment if it does not meet 4-log virus inactivation / removal?
Yes, however please note assessment or triggered source water monitoring may be required.

17. Ultraviolet Disinfection
May be considered for approval as a primary disinfection treatment if UV treatment guidelines are met
Source of supply is groundwater
Bacteria (total coliform) is documented to be coming from the groundwater source (not in distribution system)
UV unit meets ANSI/NSF 55 Standards
Raw water meets prerequisite water quality data
Iron and Manganese, color, turbidity
Suspended solid, hardness, hydrogen sulfide

18. Ultraviolet Disinfection
Advantages
No chemicals
Instantaneous bacteria inactivation
Closed system
No disinfection by-products
Low maintenance
Can be installed in a relatively small space if pre-treatment is not necessary
Relatively low initial and maintenance costs compared to chlorination systems

19. Ultraviolet Disinfection
Disadvantages
No disinfectant residual.
Currently, no known single low pressure UV units will provide 4-log inactivation/removal of viruses.
Require for assessment monitoring per GWR.
Will only be effective if the bacteria source is entering the water system prior to the UV unit.
Pretreatment may be necessary for raw water with moderate to high mineral content.
May require units to be installed in parallel if water system cannot be shut down to allow for UV maintenance or replacement.

20. Ultraviolet Disinfection

21. Ultraviolet Disinfection

22. Trivia Question
What are some of the raw water minerals to be concerned of when considering a UV treatment system?

23. Trivia Question
What are some of the raw water minerals to be concerned of when considering a UV treatment system?
Parameter
Maximum Limit
Color 15
Iron
0.3 mg/L
Manganese
0.05 mg/L
Hardness
120 mg/L
Hydrogen Sulfide
Non-Detectable
Suspended Solids
10 mg/L
Turbidity
1.0 NTU

24. Granular Activated Carbon (GAC)
Absorbs Organic Chemicals
gasoline, benzene, toluene
DDT, PCB, etc.
Controls taste & odor
Chlorine smell
Sulfur odor (rotten egg smell)
Typically 2 units are installed in series for organic removal

25. Multiple GAC units for VOC removal

26. Aeration (Air Stripping) Multi-Staged Bubble System VOC Radon TTHM
Hydrogen Sulfide
Iron Oxidation
pH Adjustment
Lowry Deep Bubble Air Stripper,

27. Iron/Manganese Removal
Filtration is typically combined with pre-oxidation
Media: Manganese Greensand, Birm, Multimedia
Regeneration / Oxidation: Potassium permanganate
Oxidation: Chlorine, Air injection
Manganese is typically oxidized at a higher pH therefore pH adjustment may be required
Phosphate – sequestering iron
Water softeners
Best for Ferrous Iron < 5 mg/L

28. Iron/Manganese Removal Continuous Regeneration
National Environmental Training Association, Inc.,
Field Guide, III-3, 1999

29. Iron/Manganese Removal Intermittent Regeneration
National Environmental Training Association, Inc.,Field Guide, III-3, 1999

30. Multiple Greensand Filters with GAC

31. Trivia Question
What is the purpose of air injection or aeration in the treatment process?
Oxidation
VOC removal
Radon removal
pH adjustment

32. Water Softeners Removal of hardness Removal of iron and manganese
Calcium and/or Magnesium
Removal of iron and manganese
Regenerate with sodium chloride or potassium chloride
If sodium levels are already elevated, potassium chloride may be preferable
Sodium notification level is 28 mg/L

33. Ion Exchange Softening
National Environmental Training Association, Inc.,Field Guide, III-6, 1999

34. Cartridge Sediment Filters
Remove silt, sediment, and other suspended matter
Use as pre-filter for other treatment processes
Sediment filter should be changed on a regular basis
Spare filters should be kept in their original wrappings
Add a tablespoon of bleach to filter housing after filter replacement

35. Trivia Questions
What is one of the functions of a water softener in a treatment process?
-- Hardness removal
-- Iron and Manganese removal
Should a cartridge filter be used for bacteria removal? No

36. Corrosion Control pH adjustment
Calcite Filter
Chemical injection
Introduction of corrosion control inhibitors
Calcite filters - protect scaling in pipes
Phosphate chemical injection - applies a protective layer on the pipes to help prevent corrosion

37. Corrosion Control
Evaluate source Water Quality Parameters (WQP) results
WQP – pH, alkalinity, calcium, conductivity, phosphate, temperature
Based on results, determine the most effective treatment system
After installation of treatment, check WQP and saturation index at entry point to confirm treatment effectiveness

38. pH Adjustment Calcite Filters
A.K.A. acid neutralizers or limestone contactors
Raise pH (typically not beyond 7.5)
Add hardness (calcium carbonate) and alkalinity which can be beneficial for corrosion control
Replace filter media periodically (i.e months)
Minimum weekly monitoring of pH level is required to be taken, recorded, and retained under RCSA Section B102(e)(7)(N)

40. Chemical Injection
pH adjustment with potassium carbonate, sodium carbonate (soda ash), or hydroxide products
Allow a wider range of pH level to be achieved
More hazardous than a calcite filter
Potential for chemical overfeed if chemical injection safety controls are not installed
Recommend injection paced proportionate to flow
Sequestering with phosphate
Daily monitoring of pH level or biweekly monitoring of phosphate level is required to be taken, recorded, and retained under RCSA Section B102(e)(7)(N)

42. Trivia Question
What is the monitoring requirement for the pH adjustment process?
-- Calcite Filters - at least weekly pH readings
-- Chemical injection – Daily pH readings
The readings must be recorded on the Treatment Effluent Log and submitted to by the 9th day of the following month.

43. Treatment Systems in Combination
Calcite followed by a water softener
Used to remove iron and manganese
Calcite raises pH and facilitates manganese removal with the water softener
Calcite adds hardness and water softener reduces hardness
Water softener followed by UV Treatment
Water softener reduces hardness, iron and manganese
Bacteria passing through UV unit is inactivated and does not “hide” under larger minerals
Many other possible combinations

44. Neutralizer + Water softener + sediment filter + UV

45. Where does the backwash go?
BACK WASH DISCHARGE MUST BE AIR-GAPPED
Not in the septic system (definition of domestic sewage in RCSA Section B103 excludes treatment backwash)
Dedicated on-site water treatment disposal system or sanitary sewer (Draft DEEP General Permit for the Discharge of Low Flow Water Treatment Wastewater)
Must meet separating distance to well
Must be at least 10 ft from existing septic system
DEEP General Permit may be required
Backwash discharge > 500 GPD

47. What is wrong?

48. What is wrong? No air gap for BW discharges
No air gap for BW discharges & storage tank drain

49. Water Treatment Equipment Chemical Feed Equipment
All chemical solution tanks (day tanks) should be equipped with tank level indicators, continuous agitators, vents to atmosphere, overlapping covers, and placed in containment basins
Proper mixing and safety instructions should be available for maintenance personnel
All chemical injection pumps must be controlled by an in-line flow sensor to prevent accidental overfeed in the case of a no-flow condition
Chemical feed rates should be proportional to flow
Injection pumps should be of the positive displacement type
Chemical injection pumps are installed as near as practical to the injection point
A separate chemical injection pump shall be used for each chemical applied

50. Water Treatment Equipment Chemical Feed Equipment (cont.)
Chemical injection pumps may be automatically or manually controlled, with automatic controls being designed so as to allow override by manual controls
Install two chemical injection pumps
Spare parts shall be available for chemical injection pumps to replace parts which are subject to wear and damage
Make-up water line to the chemical solution tank must have proper backflow prevention device installed
Hoses used to provide make-up water should never be left in the chemical solution tank after replenishing even if a vacuum breaker is installed on the hose bibb

51. Trivia Questions
Is a backflow prevention device needed for the make up water line?
YES, if no air gap exists.
What NSF Standard should be applied to drinking water chemicals?
NSF Standard 60

52. Classification of Water Treatment Plants and Small Water Systems

53. Small Water Systems
If the CPWS or NTNC serves less than 1,000 persons and either has no treatment or a treatment unit process that does not require any chemical treatment, process adjustment or media regeneration by an operator then the system is classified as a “SMALL WATER SYSTEM”

54. “Passive Treatment” - Small Water System
Treatment unit process that does not require any chemical treatment, process adjustment or media regeneration by an operator
UV Light
Calcite filter – media is replaced off site by licensed professional
Cartridge filter (whole house filter, sediment filter)
Exchange Softener – no backwash & media is regenerated off site
Granular Activated Carbon (taste & odor control)

55. Water Treatment Plant Classification Form
Points Assigned for:
Population Served
Water Supply Source
Chemical Treatment/Addition Process
Coagulation & Flocculation Process
Clarification/Sedimentation Process
Filtration Process
Other Treatment Processes
Special Processes
Residuals Disposal
Facility Characteristics - Instrumentation

56. Water Treatment Plant Classification Form
Add up all the points and determine which level treatment plant applies
TREATMENT PLANT LEVEL
Class I 30 points or less
Class II points
Class III points
Class IV 76 points or greater
Available on the Drinking Water Section website:

57. Treatment Plant Classification Activity
XYZ community public water system utilizes two wells to serve 200 people.
Well withdrawal rate
8 gpm each (8,640 gpd each)
Raw water quality
elevated iron, manganese, color & turbidity, 5.8 pH
Treatment Processes
Chlorination, pH adjustment with KOH, greensand filters with potassium permanganate (KMnO4) for regeneration and intermittent backwash discharge to on-site dedicated disposal system

59. This includes the greensand filter (5 pts) and potassium permanganate (10 pts)

60. Class II treatment plant
Total 53 points
Class II treatment plant
Requires a Class II treatment plant operator

61. Contact Information
Drinking Water Section
410 Capitol Ave, MS# 51-WAT
P.O. Box
Hartford, CT
Phone:
Emergency Phone:
Fax: