Elevated temperatures in municipal solid waste landfills can pose health, environmental, and safety risks because they can generate excessive gases, liquids, pressures, and heat that can damage landfill infrastructure. This paper discusses mechanisms that can lead to elevated temperatures in the landfill and presents a case history to establish trends in gas composition, leachate collection, settlement, and slope movement. In general, landfill gas composition changes from predominantly methane [50–60% volume-to-volume ratio (v/v)] and carbon dioxide (40–55% v/v) to a composition of carbon dioxide (60–80% v/v), hydrogen (10–35% v/v), and carbon monoxide [$>\mathrm{1,500}$ parts per million per volume (ppmv)] as temperatures elevate. As waste temperatures increase, gas and leachate pressures also increase, resulting in odors, leachate outbreaks, and potential slope instability. These observations are summarized in a progression of elevated temperature indicators that are related to field manifestations and possible remedial measures. Finally, biological and chemical processes are proposed to explain the changes in internal landfill processes.

This paper uses the San Luis Dam upstream slide to evaluate the pore-water pressures at failure and progression of the phreatic surface through the fine-grained core for drawdown stability analyses. The hydraulic conductivity and compressibility parameters of saturated and unsaturated soils are calibrated using the reservoir hydrograph and 13 piezometers in order to evaluate the pore-water pressures at failure. The analyses show unsaturated and transient seepage analyses can be used to estimate pore-water pressures during drawdown for various stability analyses and evaluate the progression of the phreatic surface through the fine-grained core. The transient results also indicate the van Genuchten parameter $\alpha$ significantly influences unsaturated soil response during drawdown. Different meshing techniques can produce consistent moisture content profiles in two different seepage software packages, but in situ measurement of moisture content and suction pressure is recommended to develop an unsaturated and transient seepage model.

We develop a novel network to segment water with significant appearance variation in videos. Unlike existing state-of-the-art video segmentation approaches that use a pre-trained feature recognition network and several previous frames to guide segmentation, we accommodate the object’s appearance variation by considering features observed from the current frame. When dealing with segmentation of objects such as water, whose appearance is non-uniform and changing dynamically, our pipeline can produce more reliable and accurate segmentation results than existing algorithms.