Vent Riser in Methane Mitigation Vent Riser in Methane Mitigation: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a vent riser is a cast iron or ABS pipe that runs through the building walls (vertically). A vent riser is part of a methane mitigation system and has…

“Toe” of a Slope Definition The “toe” of a slope is essentially the bottom, or baseline section, of the soil mass comprising the slope. It is also defined as the outermost margin of displaced material during a landslide. The toe of a slope is farthest away from the head scarp.

Active Methane Mitigation Active Methane Mitigation: Active systems refer to the mechanical and electrical components of a methane mitigation system. In fact, the definition of an Active System is available in Methane Code (Ordinance No. 175790). This is a publication by the Los Angeles Department of Building and Safety (LADBS). Moreover, further descriptions of an…

Design Methane Concentration Design Methane Concentration: In accordance with the Los Angeles Department of Building and Safety Methane Code, Ordinance Number 175790, a Design Methane Concentration is the highest recorded concentration of methane soil gas detected during the course of methane testing on a property. The Design Methane Concentration is what defines the level of…

Geosyncline Geosyncline: In geology, a geosyncline is a large-scale indentation in the Earth’s crust that is filled with sediments. A geosyncline forms due to the gradual sinking of the Earth’s crust, causing sediment from adjacent areas to gather inside. An example of a geosyncline is the Appalachian Mountains.

Permeability “Permeability” in engineering geology and geotechnical engineering refers to the property of a soil sample (or porous rock) which relates to transmitting a fluid within. Permeability measures the relative case of flow under unequal pressure. Permeability is calculated using Darcy’s Law.