{"accessLevel": "public", "bureauCode": ["020:00"], "contactPoint": {"fn": "Darren Lytle", "hasEmail": "mailto:lytle.darren@epa.gov"}, "description": "Copper is widely used in drinking water premise plumbing system materials. In buildings such as\r\nhospitals, large and complicated plumbing networks make it difficult to maintain good water quality.\r\nSustaining safe disinfectant residuals throughout a building to protect against waterborne pathogens\r\nsuch as Legionella is particularly challenging since copper and other reactive distribution system materials\r\ncan exert considerable demands. The objective of this work was to evaluate the impact of pH and\r\northophosphate on the consumption of free chlorine associated with corroding copper pipes over time. A\r\ncopper test-loop pilot system was used to control test conditions and systematically meet the study\r\nobjectives. Chlorine consumption trends attributed to abiotic reactions with copper over time were\r\ndifferent for each pH condition tested, and the total amount of chlorine consumed over the test runs\r\nincreased with increasing pH. Orthophosphate eliminated chlorine consumption trends with elapsed\r\ntime (i.e., chlorine demand was consistent across entire test runs). Orthophosphate also greatly reduced\r\nthe total amount of chlorine consumed over the test runs. Interestingly, the total amount of chlorine\r\nconsumed and the consumption rate were not pH dependent when orthophosphate was present. The\r\nfindings reflect the complex and competing reactions at the copper pipe wall including corrosion,\r\noxidation of Cu(I) minerals and ions, and possible oxidation of Cu(II) minerals, and the change in chlorine\r\nspecies all as a function of pH. The work has practical applications for maintaining chlorine residuals in\r\npremise plumbing drinking water systems including large buildings such as hospitals. \n\nThis dataset is associated with the following publication:\nLytle , D., and J. Liggett. Impact of Water Quality on Chlorine Demand of Corroding Copper.   WATER RESEARCH. Elsevier Science Ltd, New York, NY, USA, 92: 11-21, (2016).", "distribution": [{"downloadURL": "https://pasteur.epa.gov/uploads/425/Copper%20chlorine.pdf", "mediaType": "application/pdf", "title": "Copper chlorine.pdf"}, {"downloadURL": "https://pasteur.epa.gov/uploads/425/chlorine%20paper%20data.xlsx", "mediaType": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "title": "chlorine paper data.xlsx"}], "identifier": "A-3ffg-425", "keyword": ["Chlorine", "Copper", "Orthophosphate", "Oxidant demand", "drinking water"], "license": "https://pasteur.epa.gov/license/sciencehub-license.html", "modified": "2016-01-15", "programCode": ["020:000"], "publisher": {"name": "U.S. EPA Office of Research and Development (ORD)", "subOrganizationOf": {"name": "U.S. Environmental Protection Agency", "subOrganizationOf": {"name": "U.S. Government"}}}, "references": ["https://doi.org/10.1016/j.watres.2016.01.032"], "rights": null, "title": "Impact of water quality on chlorine demand of corroding copper (Supplement)"}