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Oil wells in L.A. and Residential Health Problems

Source: Oil wells in L.A.: Nearby residents grapple with health problems Magali Sanchez-Hall, a Wilmington resident for over two decades, has struggled with asthma her entire life. She says the health issue stems from her proximity to oil and gas drilling. Emma Newburger | CNBC LOS ANGELES, CALIF. — Stepping out of a coffee shop near Interstate 110 in the Wilmington neighborhood of Los Angeles, you’re immediately hit by a foul odor. Magali Sanchez-Hall, 51, who’s lived here for more than two decades, is used to the smell of rotting eggs wafting from the hundreds of oil wells operating in the neighborhood. She’s used to her neighbors describing chronic coughs, skin rashes and cancer diagnoses, and to the asthma that affects her own family, who live only 1,500 feet from a refinery. “When people are getting sick with cancer or having asthma, they might think it’s normal or blame genetics,” she said. “We don’t often look at the environment we’re in and think — the chemicals we’re breathing are the cause.” Wilmington, a predominantly working-class and Latino immigrant community of more than 50,000 people, has some of the highest rates of asthma and cancer in the state, according to a report by the non-profit Communities for a Better Environment. It’s surrounded by six oil refineries and wedged in by several freeways and the ports of L.A. and Long Beach. California, the seventh-largest oil-producing state in the U.S., has no rule or standard for the distance that active oil wells need to be from communities. For many Californians, especially Black and brown residents, acrid smells, noise and dirt from oil production is part of the neighborhood. Walking around Wilmington, pumpjacks are visible in public parks, next to schoolyards where children play and outside of people’s windows at home. At night, the sky is lit [...]

Can Enzymes Be the Key to Replacing Concrete in the L.A. Basin?

Source: Is L.A. Like a City Built on Jell-O? Can Enzymes Be the Key to Replacing Concrete? Chukwuebuka Nweke May Have the Answers - USC Viterbi | School of Engineering CHUKWUEBUKA NWEKE. Even as a child 8,000 miles away in Nigeria, Chukwuebuka Nweke remembers the 1995 Kobe, Japan earthquake. “It was a massive, devastating event,” Nweke recalled in an interview earlier this year. “That was probably the first earthquake that I got to see (video) footage about.” Now, Nweke, a geotechnical civil engineer, is a new assistant professor in the Sonny Astani Department of Civil and Environmental Engineering. Seismic hazard modeling — how the ground shakes and how that varies from place to place — is one of his key focal areas, with an aim to helping us allocate resources with priority toward the most vulnerable structures. “Some places could have a lot more damage depending on a number of things, including what’s underneath the ground and what kind of buildings are on there,” he said. “That coupled with information like what kind of service the structure provides or the density of the residing population helps determine the risk level.” For example, Nweke said, if an earthquake takes place in the middle of the desert, with a low or null population, even very large shaking wouldn’t be of great concern. However, in the L.A. basin, it’s a different story, Nweke said. “I specialized primarily in seismic site response, where I’m trying to see how much an earthquake is amplified in areas that are softer, like Los Angeles — the entire basin from Westwood to Orange County is very soft compared to the adjacent mountains,” he said. Nweke, whose scientific curiosity initially stemmed from watching various Discovery Channel series on meteors and the impact of dinosaurs, said Los Angeles is of particular interest in [...]

By kk42|October 15th, 2021|Fresno, Sacramento, Oakland, Santa Ana, Anaheim, Geotechnical California, Los Angeles, San Diego, San Jose, San Francisco, Long Beach|0 Comments

California agency finds significant liquefaction

Source: State agency finds ‘significant liquefaction’ | Local News Stories | hmbreview.com The green in this map indicates areas on the coast that may be prone to liquefication, according to the California Geological Survey. Illustration courtesy California Geological Survey The California Geological Survey last week released new hazard maps for San Mateo and Contra Costa counties that detailed where landslides and soil liquefaction could likely occur in the event of a significant earthquake. The CGS’s Seismic Hazard Zone maps found “significant” liquefaction zones in parts of San Mateo County, particularly in Half Moon Bay, Miramar and San Bruno. The state has already mapped most of the Peninsula, including Montara Mountain, Woodside and San Mateo. But La Honda and San Gregorio are two notable rural areas that don’t have data accessible yet. Each map, a roughly 60-mile zone called a “quadrangle,” accounts for three types of geologic issues caused by earthquakes: a fault rupture, landslide and liquefaction, which describes the process when seismic tremors cause soil to mix with groundwater and behave like quicksand. The state agency identifies most of the city of Half Moon Bay as inside a liquefaction zone. Its quadrangle is 74 square miles, and the liquefaction zone spans the city’s entire coastline and more, including most of the neighborhoods up to Pilarcitos Creek, including El Granada, Miramar and rural areas like Purisima Creek Redwoods Preserve. The map also identifies fault zones on both the east and west sides of the Half Moon Bay Airport, and more than half of Montara Mountain’s quadrangle is at risk of earthquake-induced landslides. The CGS maps were drafted in February but became official on Sept. 23. Land management agencies and cities use hazard maps to identify properties that require site-specific studies before breaking ground on new development. [...]

By kk42|October 11th, 2021|Sacramento, Oakland, Santa Ana, Anaheim, Geotechnical California, Earthquakes, Los Angeles, San Diego, San Jose, San Francisco, Long Beach, Fresno|0 Comments

Informed Streets Pavement Management Solution

Source: Horrocks' Informed Streets Pavement Management Solution Road maintenance is an essential component of city infrastructure. However, deciding what needs to be fixed and when is often a subject of debate. That's where Horrocks' new pavement management system comes it. Using data-driven analysis, it takes some of the guesswork out of the entire process making road maintenance more cost-effective. This will be an exceptionally great tool for cities like Anchorage, Atlanta, Boulder, Chicago, Indianapolis, Little Rock, Los Angeles, San Francisco, New York, and Phoenix. Informed Streets for Pavement Management Horrocks’ new pavement management system has been dubbed Informed Streets. This is simply because it helps create road maintenance schedules, allowing our clients to maximize their budgets by applying the right treatment to the right road at the right time. This system assesses existing pavement conditions and uses predictive models to develop unique, data-driven management plans that optimize costs and upkeep. These plans are created through the following four stages: 1. Initial Assessment and Survey Horrocks’ mobile LiDAR unit during initial survey In the initial phase of service, Horrocks’ in-house survey crews complete a thorough survey and pavement assessment of the roadways. This is done using a truck-mounted Light Detection and Ranging (LiDAR) unit to assess the pavement by collecting one million survey-grade points every second. Our experts then use this data to develop a baseline for a pavement management plan by providing one of two pavement ratings, depending on our client’s needs: the Pavement Surface Evaluation and Rating (PASER) or Pavement Condition Index (PCI). 2. Data Analysis and Planning Once the pavement rating is complete, an online platform is set up for our client, which includes the Informed Streets3D Viewer. Horrocks’ Informed Streets 3D Viewer integrates GIS systems, LiDAR point clouds, and photography in one robust platform that allows for [...]

By kk42|September 28th, 2021|Anchorage, Indianapolis, Chicago, Atlanta, Phoenix, Little Rock, Los Angeles, San Diego, San Francisco, Boulder, New York|0 Comments

California Issues Maps of Earthquake Faults to Avoid ‘Potentially Devastating’ Damage to New Buildings

Source: State Issues Maps of Earthquake Faults to Avoid 'Potentially Devastating' Damage to New Buildings - Times of San Diego The Rose Canyon Fault system. Courtesy County News Center Maps released Thursday of earthquake-prone areas are intended to ensure new construction in San Diego does not take place atop dangerous quake faults. Developed by the California Geological Survey, the regulatory Alquist-Priolo Earthquake Fault Zone maps detail where local governments must require site-specific geologic and engineering studies for proposed developments to ensure this hazard is identified and avoided. Generally, new construction for human occupancy must be set back 50 feet from the active surface trace to avoid faults that may break the surface. “Surface fault rupture is the easiest earthquake-related hazard to avoid because you can see the evidence of where it has occurred,” said Steve Bohlen, acting state geologist and head of CGS. “Surface fault rupture means that one side of a fault is moving either vertically or horizontally in relation to the other side. The deformation that movement causes is potentially devastating to buildings and infrastructure.” Two maps of revised Earthquake Fault Zones have been prepared for the Rose Canyon Fault where it comes onshore in Coronado, traversing the San Diego area to the northwest and going back offshore near La Jolla. Each of the maps covers a roughly 60-square-mile quadrangle of territory. The Alquist-Priolo Act was passed into law following the 1971 magnitude 6.6 San Fernando earthquake, which caused extensive surface ruptures that damaged buildings. Not every large earthquake, though, causes surface fault rupture. For example: the Loma Prieta Earthquake of 1989 devastated the Bay Area without breaking the surface. However, the 1992 Landers Earthquake in San Bernardino County caused surface ruptures along 50 miles, with displacements ranging from one inch to 20 feet. “Since the [...]

University of Nevada, Reno scientists and engineers collaborating on seismic survey for earthquakes

Source: University of Nevada, Reno scientists and engineers collaborating on seismic survey for earthquakes | University of Nevada, Reno University of Nevada, Reno scientists and engineers install equipment at Reno Fire Department's Station 5 on Mayberry Drive as part of a seismic study using fiber-optic cable that runs six miles from downtown Reno to west of Reno. A team of scientists and engineers from the University of Nevada, Reno are installing earthquake sensors above ground along a six-mile stretch of an existing fiber-optic telecommunication cable buried under Reno to develop a rigorous and efficient system for subsurface imaging at the large scale, and detecting earthquakes using laser and fiber-optic technology. "We'll be recording seismic signals generated by passing planes, trains and automobiles along the six-mile stretch of currently unused, buried optical fiber that runs west from Virginia Street along California Avenue and on to Mayberry Drive," Scott Tyler, professor of geological sciences and a leading expert in fiber-optic/laser sensing systems, said. "As the vibrations from the transportation system pass through the underlying geology, it causes a very small change in the optical fiber’s length, which can be recorded from the start of the fiber on South Virginia Street, using a laser-based system called Distributed Acoustic Sensing or DAS." The team, led by Elnaz Seylabi, an assistant professor in the civil and environmental engineering department, is also installing three-component high-resolution seismometers along the cable in the study area to compare traditional methods with the new DAS technology that sends a pulse of laser light through the cable and measures the perturbations in the backscattered light from every point along the cable. The fiber optic system is sensitive enough to detect footsteps as well as jet airplanes that fly by. "Instead of using thousands of geophones to measure ground vibration [...]

By kk42|September 23rd, 2021|Sparks, Juneau, Fresno, Carson City, Fairbanks, Sacramento, Elko, Badger, Oakland, Boulder City, Knik-Fairview, Santa Ana, Mesquite, College, Anaheim, Fallon, Geotechnical California, Wasilla, Geotechnical Nevada, Geotechnical Virginia, Los Angeles, Tanaina, Las Vegas, Earthquakes, San Diego, Lakes, Reno, San Jose, Kalifornsky, Henderson, Geotechnical Alaska, San Francisco, North Las Vegas, Anchorage, Long Beach|0 Comments