Milliequivalent per liter (meq/L): A unit used to express the chemical equivalence of the concentration of solutes in a solution. It is calculated by dividing the concentration of a substance (in mg/L) by its equivalent weight. This measurement helps in understanding the reactive capacity of ions in the solution.
Effective Size (D10) “Effective Size” (D10) is an engineering geology term. Effective Size represents a diameter that directly corresponds to the percentage, by weight, of grains that equal to 10% on the grain-size diagram. To illustrate, 10% of the soil sample particles are finer-grained, and 90% of the sample particles are coarser than the “effective…
Perforated Horizontal Pipe in Methane Mitigation Perforated Horizontal Pipe: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a perforated horizontal pipe is a PVC or ABS pipe that contains a series of small holes or narrow openings placed equidistantly along the length of the pipe, and is…
Gap-Graded The term “Gap-Graded” is used by geologists, engineers, and soil scientists in the geotechnical engineering field to describe the gradation of a soil sample, specifically when some particle sizes are missing. Aside from being “gap graded,” a soil sample can be described as “well-graded” (also referred to as poorly sorted), or “poorly graded” (or…
Focus (Hypocenter) Focus (Hypocenter): In the seismology branch of geology, a focus, or hypocenter, refers to the specific place where an earthquake rupture originates. The focus, or hypocenter, underlies the epicenter when an earthquake occurs at a dip-slip fault, strike-slip fault, oblique-slip fault, or listric fault. In the event of an earthquake, geologists, and seismologists…
Rock Stratigraphic Unit In the field of geology, a rock stratigraphic unit, or a lithostratigraphic unit, is a geologic formation that is identifiable by a specific lithology, as well as a consistent stratigraphic position. For example, the Monterey Formation is a rock stratigraphic unit, as it tends to consistently comprise the same gravel and sand…
Environmental Consultant Environmental Consultant: An environmental consultant is an expert of any profession or field, who focuses their skills and knowledge towards matters that improve the environment. Environmental consultants are typically scientists with expertise in geology, chemistry, physics, and engineering. Environmental Consultants Working Towards Environmental Sustainability Environmental consultants generally provide professional services that aim towards…
