Geological Model for Naturally Occurring Asbestos Content Prediction in the Rock Excavation of a Long Tunnel (Gronda di Genova Project, NW Italy)

2020 ◽  
Vol 26 (1) ◽  
pp. 107-112
Author(s):  
Luca Barale ◽  
Fabrizio Piana ◽  
Sergio Tallone ◽  
Roberto Compagnoni ◽  
Chiara Avataneo ◽  
...  
Keyword(s):  
Structural Features ◽  
Northern Italy ◽  
Geological Model ◽  
Rock Excavation ◽  
Representative Sampling ◽  
Highway Tunnel ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos ◽  
Nw Italy ◽  
Sampling Procedures

ABSTRACT For a reliable evaluation of the geo-environmental risk due to naturally occurring asbestos (NOA) during rock excavation of large infrastructure projects, a proper procedure is needed. First, it is necessary to provide a detailed geological model tailored to the NOA-related issues that should drive the rock sampling procedures in order to obtain a representative sampling. The sampling procedures should take into account lithological variability and relative spatial distributions of the rock units. The geological model for NOA should be thus constrained by the main NOA petrofacies occurring in a given geotectonic context, which take into consideration both the mineralogical and structural features, and the identification of NOA homogeneous zones in which the NOA petrofacies are distributed. In this paper, some geo-environmental problems faced during the excavation, in meta-ophiolites, of a long highway tunnel are described. The geological model of the complex setting of the tunnel area (northern Italy, Alps-Apennines junction) is described, focusing on how the NOA-related problems were addressed to allow reliable and detailed estimations of NOA contents for each NOA homogeneous zone and the relevant tunnel layout segment.

Naturally Occurring Asbestos in Valmalenco (Central Alps, Northern Italy): From Quarries and Mines to Stream Sediments

2020 ◽  
Vol 26 (1) ◽  
pp. 47-52
Author(s):  
Alessandro Cavallo ◽  
Jasmine Rita Petriglieri
Keyword(s):  
Electron Microscopy ◽  
Stream Sediments ◽  
Northern Italy ◽  
World Health ◽  
Central Alps ◽  
Representative Sampling ◽  
Naturally Occurring ◽  
Critical Issues ◽  
Naturally Occurring Asbestos ◽  
Health Organization

ABSTRACT The Valmalenco area (central Alps, northern Italy) is an excellent case study for naturally occurring asbestos (NOA) because of the huge outcrops of serpentinites and widespread quarrying and mining activities. Extensive sampling of rocks, soils, stream sediments, and airborne asbestos has been in progress since 2004. The combined use of scanning electron microscopy and transmission electron microscopy has proven to be effective for the correct discrimination between asbestiform and non-asbestiform mineralogical varieties (but falling into the World Health Organization fiber definition), whereas phase contrast microscopy has not proven suitable because of the very small size of fibrils after strong mechanical fragmentation. The quantitative analysis of “massive” samples (rocks, soils, and sediments) requires accurate and representative sampling as well as specific counting and discrimination criteria to determine NOA. Over a decade of experience has allowed us to identify critical issues and adopt effective preventive measures.

Assessment of NOA risk for the excavation of a highway tunnel system ("Gronda di Genova", Italy): from NOA-oriented geological model to asbestos quantification

2020 ◽  
Author(s):  
Fabrizio Piana ◽  
Chiara Avataneo ◽  
Luca Barale ◽  
Serena Botta ◽  
Roberto Compagnoni ◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Geological Model ◽  
Representative Sampling ◽  
Highway Tunnel ◽  
Tunnel Section ◽  
Risk Zonation ◽  
Minimum Number ◽  
Definition Of ◽  
Tunnel System

<p>For a reliable evaluation of the geo-environmental risk related to the presence of naturally occurring asbestos (NOA) in rocks excavated for large infrastructural projects, a proper procedure has to be followed in order to achieve:</p><p>1) the definition of a detailed geological model, tailored on NOA-related issues;</p><p>2) a representative sampling;</p><p>3) a reliable quantitative determination of asbestos content in rock samples.</p><p>Here we describe the approach followed for the evaluation of the NOA content for the excavation of a complex highway tunnel system (“Gronda di Genova” NW Italy), in NOA-bearing meta-ophiolite rocks. The NOA-oriented geological model has been constrained by the individuation of the main “NOA-related petrofacies” —i.e., classes of rocks with common lithological, structural and NOA content features—, and by the identification of “homogeneous zones” – i.e. geological units into which the NOA petrofacies are distributed. Implementation of Gy’s theory on sampling was used and here described to maintain statistical validity during sample processing from the primary rock sample to the analytical sample. SEM-EDS procedure for the quantitative determination of NOA content was improved with an error analysis delivering the minimum number of fibers to be measured to achieve the best analytical results.</p><p>The obtained results allowed the prediction of the NOA hazard in terms of risk zonation along the tunnel section and for the evaluation of the amount of asbestos-bearing spoil to be excavated and managed.</p>

Naturally Occurring Asbestos Assessment, Exposure Prevention Strategies During Construction, and Capping for Long-Term Protection: a California, USA Example

2020 ◽  
Author(s):  
Sarah Kalika
Keyword(s):  
School Improvement ◽  
Best Practices ◽  
Residential Buildings ◽  
The United States ◽  
Guidance Document ◽  
School Construction ◽  
Improvement Project ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos ◽  
Sampling Procedures

<p>The government of California, in the United States, has created requirements that are intended to protect the public from naturally occurring asbestos (NOA), partly due to the widespread areas in which asbestos minerals (including chrysotile and various amphiboles) are found within the state.Over ten years ago, the California Department of Toxic Substances Control Schools Unit published a thorough set of guidelines for addressing NOA at school construction sites.Their guidance document includes soil sampling procedures and frequency, recommended laboratory analytical testing methods, construction best practices to protect nearby residents from airborne exposures, capping methods to prevent re-exposure to students and public following the completion of the school improvement project, and follow-up procedures to ensure the capping method remains protective.Many of these best practices have been adapted into the construction process for commercial and residential buildings.<span>  </span>In California, protection of air is the regulated by Air Quality Management Districts, who regulate the generation of airborne asbestos as an air pollutant.Additionally, workers who are employed by a company, and working at a job site where asbestos is present, are protected by California Occupational Safety and Health (Cal-OSHA). Cal-OSHA requires varying protective measures to be implemented, based on the amount of asbestos that the worker is exposed to during their time at the construction project.This presentation will review the various regulations and best practices used in California by comparing a school construction project with a commercial office building. </p>

Dealing with asbestos presence in tunnel excavation: the Castagnola case study and the importance of the geological model

2020 ◽  
Author(s):  
Oliviero Baietto ◽  
Francesco Amodeo ◽  
Martina Vitaliti ◽  
Giovanni Parisi ◽  
Alberto Scuderi ◽  
...  
Keyword(s):  
Surface Investigation ◽  
High Velocity ◽  
Ventilation System ◽  
Geological Model ◽  
Tunnel Excavation ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos ◽  
Storage Methods ◽  
And Storage

<p>The presence of Naturally Occurring Asbestos (NOA) is one of the greatest danger during excavations and tunneling.  The most important instrument for the NOA content prediction is the geological model.</p><p>As part of the consultancy provided in the works of the "Terzo valico dei Giovi" which includes the excavation of numerous tunnels in areas potentially affected by rocks containing asbestos, the case study of the tunnel called "Castagnola" is illustrated. The opera is the new high velocity railway connection between Genova and Milano and the case study is located in the Piedmont southern area near Fraconalto (AL).</p><p>The “Castagnola” tunnel area is characterized by greenish - reddish rocks metabasalt covered by recent grey shales in the upper part of the area; it refers to the ophiolitic Figogna Unit, elongated in a north-south direction, which belongs to Sestri-Voltaggio Zone.</p><p>Starting from geological sections and thanks to surface investigation and core drilling, an effective geological model was built.</p><p>This study highlights how, during the progress of the works, situations other than the forecast geological model are encountered. It also highlights the importance of the environmental monitoring of the airborne fibers dispersion inside the tunnel, which has proved extremely effective even in the presence of low asbestos content in the excavated rock.</p><p>Moreover, this study describes the trends in asbestos content in the material excavated during the route of the tunnel in comparison with the concentration of airborne fibers. Furthermore, the management of the asbestos problem, from the abatement of dust to the excavation and storage methods and the installation of efficient technologies such as an aspirating ventilation system already successfully tested in a previous excavation phase, are presented.</p>

Impacts of land use on spatial distribution of mortality rates of cancers caused by naturally occurring asbestos

2012 ◽  
Vol 22 (5) ◽  
pp. 516-521 ◽  
Author(s):  
Binggan Wei ◽  
Xianjie Jia ◽  
Bixiong Ye ◽  
Jiangping Yu ◽  
Biao Zhang ◽  
...  
Keyword(s):  
Land Use ◽  
Spatial Distribution ◽  
Mortality Rates ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos

scholarly journals Impact of Naturally Occurring Asbestos on Asbestos Ban: Regulations and Experience of the Republic of Korea

2022 ◽  
Vol 19 (2) ◽  
pp. 742
Author(s):  
Jiwoon Kwon
Keyword(s):  
Preventive Measures ◽  
Control Measures ◽  
Exposure Risk ◽  
Close Collaboration ◽  
Mineral Particles ◽  
Naturally Occurring ◽  
Transmission Electron ◽  
The Future ◽  
Naturally Occurring Asbestos ◽  
The Republic

This review examined the main issues debated in Korea regarding the production and use of materials containing naturally occurring asbestos (NOA) as impurities, and investigated the impacts of these debates on the asbestos ban, as well as the future implications. In Korea, incidents associated with the production and use of NOA-contaminated talc powders, construction rocks, serpentinites, and dolomite rocks raised public concern and led to accelerating the ban on asbestos. The main controversies concern policies on appropriate asbestos content limits, whether materials containing a trace amount of NOA should be banned, and the control of materials with high human exposure risk. To address recurring controversies, the implementation of preventive measures to manage elongated mineral particles and the use of transmission electron microscopy for more sensitive analysis need to be discussed, along with reaching social agreement on the controversial policies. To minimize the potential exposure to asbestos that may occur during the production and use of industrial minerals in the future, it is necessary to apply occupational exposure control measures and monitor the health effects of the relevant population groups. These national policies on NOA should be prepared based on close collaboration and discussion with policymakers, industry stakeholders, and related academic experts.

scholarly journals Total Syntheses of Pladienolide-Derived Spliceosome Modulators

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5938
Author(s):  
Jaehoon Sim ◽  
Eunbin Jang ◽  
Hyun Jin Kim ◽  
Hongjun Jeon
Keyword(s):  
Total Synthesis ◽  
Natural Product ◽  
Structural Features ◽  
Synthetic Approach ◽  
Synthetic Analog ◽  
Phase I Clinical Trials ◽  
Total Syntheses ◽  
Naturally Occurring ◽  
Anti Cancer ◽  
Synthetic Approaches

Pladienolides, an emerging class of naturally occurring spliceosome modulators, exhibit interesting structural features, such as highly substituted 12-membered macrocycles and epoxide-containing diene side chains. The potential of pladienolides as anti-cancer agents is confirmed by H3B-8800, a synthetic analog of this natural product class, which is currently under Phase I clinical trials. Since its isolation in 2004 and the first total synthesis in 2007, a dozen total syntheses and synthetic approaches toward the pladienolide class have been reported to date. This review focuses on the eight completed total syntheses of naturally occurring pladienolides or their synthetic analogs, in addition to a synthetic approach to the main framework of the natural product.

Overview of Naturally Occurring Asbestos in California and Southwestern Nevada

2020 ◽  
Vol 26 (1) ◽  
pp. 9-14
Author(s):  
R. Mark Bailey
Keyword(s):  
Sierra Nevada ◽  
North American ◽  
Volcanic Belt ◽  
Island Arc ◽  
North American Plate ◽  
Mountain Range ◽  
The North ◽  
Rock Types ◽  
Naturally Occurring ◽  
Naturally Occurring Asbestos

ABSTRACT Naturally occurring asbestos (NOA) is being discovered in a widening array of geologic environments. The complex geology of the state of California is an excellent example of the variety of geologic environments and rock types that contain NOA. Notably, the majority of California rocks were emplaced during a continental collision of eastward-subducting oceanic and island arc terranes (Pacific and Farallon plates) with the westward continental margin of the North American plate between 65 and 150 MY BP. This collision and accompanying accretion of oceanic and island arc material from the Pacific plate onto the North American plate, as well as the thermal events caused by emplacement of the large volcanic belt that became today's Sierra Nevada mountain range, are the principal processes that produced the rocks where the majority of NOA-bearing units have been identified.

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