Liquefaction Liquefaction: Liquefaction is the process by which there is: (1) a sudden and significant decrease of shear resistance in a soil sample (cohesion-less); (2) a sudden (but temporary) increase of the pore-water pressure of a substance; and (3) a solid mass of soil that is transformed into a fluid state mass. In the event…

Hardpan (Caliche) “Hardpan” is a highly dense and solid layer of soil near the ground surface, which is usually comprised of clay or silty-clay soils. Hardpan forms by cementation over time, during the process of precipitation of insoluble substances such as calcium carbonates, silica, iron oxides, and other organic matter. “Hardpan” is a term mostly…

Waterproofing Barrier System Definition A waterproofing barrier system guarantees full protection to walls, foundations, and methane mitigation systems that are below grade and are susceptible to moisture penetration. Typically, the best way to protect a retaining wall against moisture is the application of a waterproofing barrier on the backside of it, after pouring concrete, but…

Potentiometric Surface The term “Potentiometric Surface” means the hydrogeological surface that represents the total hydraulic head of groundwater from a confined aquifer or semi-confined aquifer that’s under pressure. The Potentiometric Surface of an aquifer is defined by the level to which water will rise in a groundwater monitoring well (that’s exclusively screened within said aquifer).

Feldspars Feldspars: In the field of geology, and the branch of mineralogy, feldspars are a mineral group, that is the most common amongst the earth’s crust. In fact, there are two types of feldspars: plagioclase feldspar and orthoclase feldspar.

Control Panel in a Methane Mitigation System Control Panel of a Methane Mitigation System: A methane mitigation control panel is the brain behind the active mitigation system. In accordance with the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a control panel synchronizes methane alarm units with sensors and the…