CHARLESTON, W.Va. -- A state-sponsored study meant to examine potential pollution from the boom in natural gas drilling never actually tested key wastes from the Marcellus Shale formation, according to a West Virginia University researcher who led the effort.Teams performing the legislatively mandated review examined only materials from the vertical portion of wells, not from the horizontal drilling at those same sites, which would have included Marcellus Shale mud and drill cuttings.The omission is important because researchers believe material from the Marcellus Shale is generally more radioactive, and citizen groups are expressing growing concern about the risks of handling and disposal of radioactive drilling wastes.And, the report's major weakness is being highlighted just as the Legislature returns to Charleston for its 2014 session, after hearing throughout the year about studies finding flaws in Gov. Earl Ray Tomblin's drilling bill that passed in 2011.Researchers noted the lack of Marcellus data in a 141-page report last February, and the state Department of Environmental Protection mentioned it in a summary prepared for lawmakers by agency officials.But the issue had not received much public attention until a legislative briefing during an interim committee meeting held late Sunday afternoon."We can't dismiss the potential risks," Paul Ziemkiewicz, director of WVU's Water Research Institute, which coordinated the study, told lawmakers. "We just haven't characterized it."In a presentation to committee members, Ziemkiewicz said that the DEP had initially arranged for researchers to obtain Marcellus drilling mud from a Stone Energy site in August 2012. When researchers tried to take samples on three different dates, they were told each time that "drilling malfunctions" made it impossible for them to do so.DEP officials identified a second sampling site operated by Chesapeake Energy, the presentation said. Poor weather related to Superstorm Sandy stopped the drilling there prior to reaching to Marcellus, the presentation said."The company indicated it would notify WVDEP and WVU when drilling resumed," the presentation said. "However, when WVDEP followed up with the company after Hurricane Sandy, the agency and WVU were notified that the horizontal leg was completed and no samples were available."The presentation said that by then, it was early November, and the DEP "had no readily available site and the time required to analyze the samples was between 6 and 8 weeks.""So, no other sites were selected by WVDEP for solid sampling since it would delay submission of the final report beyond the end of December 2012 -- the point necessary in order to provide recommendations to the Legislature," the presentation said.Ziemkiewicz recommended that additional work be done to sample drilling mud from the Marcellus formation. He said the data are needed to ensure that drilling wastes are being sent to appropriate types of disposal facilities and being handled properly."This stuff isn't just dirt that you can apply somewhere," Ziemkiewicz said in a Monday interview. "You can't go around with the assumption that this stuff is innocuous."Reach Ken Ward Jr. at or 304-348-1702.