The Environmental Protection Agency today posted a summary of five technical roundtables held last year on the agency’s Hydraulic Fracturing Study and the practice’s effects on drinking water supplies. “Fracking” as its known, is highly controversial because of its negative effects on the environment. This is playing out across Pennsylvania where drilling of the Marcellus Shale natural gas deposit is taking hold — and causing waves of protest.

Among the topics of the roundtables, held in November: chemical mixing, water acquisition and waste-water treatment and waste disposal. The 28-page summary of those EPA roundtables can be found here. For more on upcoming EPA roundtables, visit here.