FracFocus went online last April and now information about chemical additives used in more than 10,150 hydraulically fractured, or fracked, wells across the United States.The searchable website (www.fracfocus.org) is maintained by the Ground Water Protection Council and the Interstate Oil and Gas Compact Commission, two intergovernmental agencies. The U.S. Department of Energy provided financial assistance.The chemical-disclosure registry has 114 participating firms.The site is voluntary in Ohio but is mandatory in five states: Colorado, Montana, Louisiana, North Dakota and Texas. West Virginia, Alaska and Oklahoma are considering similar disclosure rules.Companies, including Chesapeake Energy Corp., the biggest player in Ohio’s Utica shale, voluntarily provide the site with information about its wells and the chemicals used in hydraulic fracturing.The website provides well location by longitude and latitude, vertical depth and date the rock underground was fractured. It shows how much water was used in the process.It identifies the chemicals used, their purpose, the chemical's ingredients, the maximum ingredient concentration (a percentage by mass) and the active ingredient concentration in the fracking liquid (again a percentage by mass).It does not provide weight or concentration, only a percentage of mass.It covers all wells drilled after Jan. 1, 2011.Companies are allowed to keep some materials undisclosed as proprietary or trade secrets,The information comes from the chemical suppliers for the drilling and there is no third-party verification.The information is posted after the fracturing is completed.Chesapeake is a strong supporter of the voluntary registry.Environmentalists worry that the success of the FracFocus program will make it impossible to win approval for a mandatory federal disclosure program.Voluntary disclosure is “not good enough” and a mandatory program would be better, said Amy Mall of the Natural Resources Defense Council, a national eco-group.“FracFocus is a nice gesture, but it does not satisfy the public need for full disclosure of fracking chemicals” as would be provided under proposed federal legislation, Mall said.— BOB DOWNING