Effect of biogas generation on radon emissions from landfills receiving radium-bearing waste from shale gas development.

Unlabelled: Dramatic increases in the development of oil and natural gas from shale formations will result in large quantities of drill cuttings, flowback water, and produced water. These organic-rich shale gas formations often contain elevated concentrations of naturally occurring radioactive materials (NORM), such as uranium, thorium, and radium. Production of oil and gas from these formations will also lead to the development of technologically enhanced NORM (TENORM) in production equipment.

Estimating aquifer channel recharge using optical data interpretation.

Recharge through intermittent and ephemeral stream channels is believed to be a primary aquifer recharge process in arid and semiarid environments. The intermittent nature of precipitation and flow events in these channels, and their often remote locations, makes direct flow and loss measurements difficult and expensive. Airborne and satellite optical images were interpreted to evaluate aquifer recharge due to stream losses on the Frio River in south-central Texas.

Fatal flaws in measuring landfill gas generation rates by empirical well testing.

Well testing procedures, such as the Tier 3 methodology specified in the U.S. Code of Federal Regulations (CFR) Subtitle D, are commonly used for directly estimating landfill gas (LFG) emissions at municipal solid waste (MSW) landfills.

The capture efficiency map: the capture zone under time-varying flow.

The capture zone or contributing area of a ground water extraction well can be defined as that portion of the aquifer from which the well draws its water. Accurate delineation of capture zones is important in many ground water remediation applications and in the definition of wellhead protection areas. Their mathematical delineation is often simplified by using quasi-steady-state models based on time-weighted average pumping rates and background hydraulic gradients.