A process for the solidification of liquid waste prior to disposal in a landfill, and an impermeable container in which the liquid waste is solidified.

A control system for controlling extraction of landfill gas from a landfill via a gas extraction system comprising well piping, the landfill gas having a first temperature when extracted, the control system comprising: a gas composition chamber coupled to the well piping and comprising at least one sensor configured to measure one or more characteristics of a landfill gas sample in the gas composition chamber; a temperature control mechanism configured to heat the landfill gas sample in the gas composition chamber to a second temperature at least a threshold amount greater than the first temperature; and a controller configured to control the at least one sensor to measure the one or more characteristics of the landfill gas sample in the gas composition chamber when a temperature of the landfill gas sample in the gas composition chamber is at least the threshold amount greater than the first temperature.

A gas monitoring and control system including a gas sampling chamber, sampling inlet and outlet valves, a pump and a controller. Sensors are disposed within the interior chamber that sense characteristics of a gas from a gas source and generate representative signals. The sampling inlet and outlet valves i) allow the gas into the gas sampling chamber while operating in a gas sampling state, and ii) allow ambient air into the gas sampling chamber while operating in a purge state. The pump i) causes the gas to flow through the gas sampling chamber while operating in the gas sampling state or ii) causes ambient air to flow through the gas sampling chamber while operating in the purge state. The controller causes the sampling inlet and outlet valves, and the pump to alternate operating in the gas sampling or purge state to selectively expose the sensors to the gas.

A shear pin supported cleaner finger assembly includes a frame member, a support member attached to the frame member, the support member defining a pivot point and a reactive point. A cleaner finger is pivotally attached to the support member at the pivot point, and a shear pin is positioned at the reactive point.

A soil conditioner apparatus and method condition soil for compaction. The conditioner apparatus creates a heated stream of air directed toward the ground as the conditioner moves along the ground. A mixer on the conditioner mixes soil in the path of the heated air to dry the soil. Some embodiments of the mixer will propel the soil into the air in the stream of heated air. The conditioner can decrease moisture in the soil in the location where the soil will be compacted. In some embodiments, ambient air is introduced into the conditioning process by additional blowers. The mixer can also mix added soil and other additives to the soil in location. The conditioner apparatus may take the form of an apparatus towed by another vehicle, a set of towed apparatuses, an apparatus carried by another vehicle, or a self propelled vehicle having the operational elements of the soil conditioner.

A low-profile fluid collection conduit includes an elongate outer cover having an upper portion and a lower portion generally opposite the upper portion, with the outer cover being much wider than it is tall and defining an interior volume. An elongate rigid spacer is fitted within the interior volume of the elongate outer cover, with the elongate spacer allowing the majority of the interior volume to be unfilled so as to permit the flow of fluid along and within the elongate outer cover. The collection conduit is used with a fluid-impermeable membrane as part of a landfill fluid collection and conveyance system.

The invention provides a method for efficiently adjusting existing landfill gas well head control devices in a manner which reduces the overall air migration into the landfill's gas collection systems in a short period of time. The method also provides for mapping out hydrogen sulfide concentration areas of landfills; allowing for efficient evaluation and selective reduction of hydrogen sulfide.

A control system for controlling extraction of landfill gas from a landfill via a gas extraction system, the gas extraction system comprising well piping for coupling a plurality of wells to a gas output. The control system comprises a controller configured to: obtain a value indicating measured energy content of landfill gas collected at the gas output from the plurality of wells; determine whether the measured energy content is different from a target energy content; and in response to determining that the measured energy content is different from the target energy content: control a plurality of valves disposed in the well piping to change flow rates of landfill gas being extracted from at least some of the plurality of wells at least in part by changing degrees to which the plurality of valves are open.

Described herein are embodiments of a control system that automatically (1) determines whether a gas extraction system is in a state in which landfill gas is being released into the atmosphere, and (2) automatically controls landfill gas flow to mitigate, prevent and/or stop the release of landfill gas. The control system may control a valve to control flow of landfill gas through well piping of the gas extraction system. The pressure of landfill gas in the well piping at a location upstream of the valve may indicate whether there is a risk of landfill gas being released into the atmosphere. The control system may adjust a position of the valve in response to determining that the pressure at the location upstream of the valve indicates that there is a risk of landfill gas being released into the atmosphere.

The invention relates to a sealing wall building material, which has a binding agent with cement and aggregates. It is provided according to the invention that the binding agent comprises a mixture of cement and fly ash, wherein it is free of clay material, and that it has an impermeability with a kf value of 10.sup.7 m/s and less.