Chloramines

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Chloramines are a secondary water treatment chemical created by combining ammonia with chlorine. The Rivanna Water and Sewer Authority staff decided to use chloramines instead of traditional chlorine in order to meet new EPA requirements by 2014.[1] On July 25, 2012, the RWSA, in collaboration with the Albemarle County Service Authority, the Charlottesville City Council, and the Albemarle Board of Supervisors unanimously decided to end consideration of chloramines as a water treatment option.[2][3]



History

  • March 2011- The consulting firm, Hazen and Sawyer, began conducting studies to determine how the RWSA could meet new requirements detailed in Stage 2 of the Disinfectant Byproduct Rule and staff from the the RWSA, the city of Charlottesville and the Albemarle County Service Authority agreed to recommend the addition of chloramines to the RWSA's next capital budget.
  • May 2011- The RWSA authorized the chloramines project.
  • February 2012- The capital improvement budget is approved and chloramines gain the public's attention.
  • June 21, 2012- "Safe Water Symposium" is held, featuring a panel of experts on both sides of the chloramine debate.[4]
  • June 2012- Local officials meet with EPA officials to discuss chloramines and granular activated carbon filtration.[5]
  • July 25, 2012- A meeting of the four boards responsible for the water supply, the RWSA, the ASCA, City Council, and Albemarle Board of Supervisors, met to hear the public's opinion and discuss water treatment options. They unanimously decided to no longer pursue chloramines as an option.[2]

EPA Requirements

The Rivanna Water and Sewer Authority must meet Stage 2 of the Disinfectant Byproduct Rule by 2014.[1] This requires that the levels of haloacitic acids be less than 60 parts per billion and trihalomethane levels be less than 80 ppb.[1] The requirements must be met by 2014 or the RWSA risks up to $25,000 of fines for every day it is not in compliance.[6] Haloacitic acids and trihalomethanes are carcinogenic when ingested in high doses. They are created when chlorine or chloramines interact with organic matter in water.[1]

Hazen and Sawyer

The consulting firm Hazen and Sawyer was hired by the RWSA to research options that would allow the RWSA to meet the EPA’s requirements. [6]

Alternatives

Hazen and Sawyer researched other possibilities for meeting the EPA's new requirements. The processes they evaluated were chloramine residual disinfection, ultra-violet disinfection with chloramine residual disinfection, magnetic ion exchange resin, granular activated carbon contactors, and nanofiltration.[7].

Hazen and Sawyer and the RWSA estimated the addition of chloramines to cost around $5 million. [4] The next option was granular activated carbon filtration which was estimated to cost around $18.3 million [4]

In response to concerns about health concerns and the high cost of carbon filtration (GAC). The RWSA and Hazen and Sawyer developed a 'hybrid' GAC option, which would involve running large amounts of water through GAC filters and then combining it with regularly treated water to reduce byproducts.[2] It would be less expensive than traditional GAC and would not involve chloramines.[2]

Response from the Public

In response to public concerns about the safety of chloramines use, the RWSA held a "Safe Water Symposium" on the pro's and con's of chloramines on June 21, 2012. [4] The event featured a panel of experts consisting of Dwight Flammia, a toxicologist with the Virginia Department of Health; Jerry Higgins, superintendant manager of the Blacksburg-area water authority, which uses chloramines; Jim Moore, a professional engineer with the VDH; Ben Stanford, director of applied research at the RWSA and consultant with Hazen and Sawyer; and Steve Vaya from the Washington, D.C. office of the American Waterworks Association.[6] Other panelists were Marc Edwards, a Virginia Tech civil and environmental engineering professor who studied the correlation between Washington’s use of chloramines and its problems with lead leaching; Robert Bowcock, the environmental investigator for Integrated Resource Management; and Susan Pickford of the Chloramines Information Center.

At the meeting, some members of the public supported the use of granular activated carbon filtration instead of chloramines. They listed concerns about the potential health effects of chloramination and supported granular activated carbon filtration's ability to remove numerous pathogens from water.

In response to public concerns, City Councilor Kathy Galvin, Supervisors Kenneth C. Boyd and Duane E. Snow, as well as RWSA executive director Thomas L. Frederick, Jr. met with EPA officials in July 2012 to discuss chloramines and granular activated carbon. Following the meeting, the local officials reported that the EPA supported both treatment alternatives and still considered chloramines to be safe and effective. The EPA also reported that recent studies suggest carcinogen risks may be lower with chloramines compared with free chlorine.[5]

July 2012 Public Hearing

Following the June 2012 symposium, a public hearing was scheduled for July 25, 2012 to receive public comment from the Charlottesville-Albemarle community.[8] The meeting, which was led by the RWSA, the Albemarle County Service Authority, the Charlottesville City Council, and the Albemarle Board of Supervisors to discuss potential changes to water treatment and receive public comment. During the course of the meeting the four boards agreed unanimously to end consideration of chloramination as a means of treating water in the area.[3] Robert W. Bowcock, an environmental investigator with the California-based firm, Integrated Resource Management, has suggested that the $18.3 million cost of the alternative, granular activated carbon, may have been overestimated by the consulting firm Hazen & Sawyer.[2]

References

  1. 1.0 1.1 1.2 1.3 Web. Safety of chloramines questioned: Disinfectant to be added into local water supply starting in 2014, Courtney Beale and Brian Wheeler, Charlottesville Tomorrow, 13 March 2012, retrieved 20 June 2012.
  2. 2.0 2.1 2.2 2.3 2.4 Web. Officials end consideration of chloramines for water treatment, Brian Wheeler & Courtney Beale, Charlottesville Tomorrow, 25 July, 2012, retrieved 26 July, 2012.
  3. 3.0 3.1 Web. Chloramine complaints drive decision to go with costlier water filtration, Graelyn Brashear, C-VILLE Weekly, Portico Publications, August 2, 2012, retrieved August 27, 2012.
  4. 4.0 4.1 4.2 4.3 Web. More than a hundred residents come to chloramines panel, Brian Wheeler, Charlottesville Tomorrow, 21 June 2012, retrieved 22 June 2012.
  5. 5.0 5.1 Web. As scientific debate continues, local officials hear from EPA on chloramines, Brian Wheeler & Courtney Beale, Charlottesville Tomorrow, July 23, 2012, retrieved July 23, 2012.
  6. 6.0 6.1 6.2 Web. Water authority and activists preparing for chloramines information session, Courtney Beale, Charlottesville Tomorrow, 18 June 2012, retrieved 20 June 2012.
  7. Rivanna Water and Sewer Authority. Executive Summary. Charlottesville: Rivanna Water and Sewer Authority, 2012. Web. [1]
  8. Web. Local officials and residents reflect on chloramines and prepare for public hearing, Courtney Beale, Charlottesville Tomorrow, 15 July, 2012, retrieved 18 July, 2012.