https://doi.org/10.1007/s12583-020-1052-0, Fang K, An P, Tang H, Tu J, Jia S, Miao M, Dong A (2021) Application of a multi-smartphone measurement system in slope model tests. Also known as trench collapse, 168 workers lost their lives in this type of accident from 2011 to 2018, according to the Bureau of Labor Statistics (BLS). You will receive a message if you forgot to answer one of the questions. cave-inWhat is the typical point of failure in an excavation? Acta Geotech 16:28992916. Cemented soil means a soil in which the particles are held together by a chemical agent, such as calcium carbonate, such that a hand-size sample cannot be crushed into powder or individual soil particles by finger pressure. They were at once the lay face of the church, the spiritual heart of civic government, and the social kin who claimed the allegiance of peers and the obedience of subordinates. Learn more about Institutional subscriptions, An P, Fang K, Jiang Q, Zhang H, Zhang Y (2021) Measurement of rock joint surfaces by using smartphone structure from motion (sfm) photogrammetry. Examples of Type C soil include gravel, and sand. Footing The PLT has been used in geotechnical analysis for over thirty years (ISRM, 1985). Properly training locators is essential to prevent utility damages. Dul L, Leelasukseree C (2020) Standup time estimation of undercut moist sand slope using numerical simulation. Acta Geotechnica When done safely, trenching operations can reduce worker exposure to other potential hazards include falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment. Quality assurance efforts including locate audits and field interventions are critical to underground utility damage prevention. If the soil breaks into clumps that do not break into smaller clumps (and the soil can be broken only with difficulty), the soil is considered non-fissured unless there is visual indication of fissuring. Benching When there is enough space available, and the soil exhibits an unconfined cohesive Utilities can increase excavator and homeowner awareness of the 811 ticketing process and educate on how it works through a mix of traditional marketing tactics (direct mail, point-of-sale advertisements, event sponsorships, earned media, etc.) The more cohesive the soil particles; the more the entire soil mass tends to stick together rather than crumble. J Earth Sci 31:10871096. (In Chinese), Hu W, Scaringi G, Xu Q (2018) Acoustic emissions and microseismicity in granular slopes prior to failure and flow-like motion: the potential for early warning. Understand more about asbestos and how to control the risks from it. The pre-failure, failure, and post-failure stages of the slope model are analysed through multi-field monitoring. Describe all the sources of amplification in the insulin receptor system. Soil failure is defined as the collapse of part or all of an excavation wall. Sandy clay. Landslides 11:167194. https://doi.org/10.1007/s11440-022-01627-0, https://doi.org/10.1007/s11440-011-0152-5, https://doi.org/10.1016/j.enggeo.2019.105295, https://doi.org/10.1007/s12583-020-1052-0, https://doi.org/10.1016/j.enggeo.2021.106424, https://doi.org/10.1016/j.cageo.2013.10.015, https://doi.org/10.1016/0148-9062(87)91524-5, https://doi.org/10.1007/s10346-019-01233-4, https://doi.org/10.1016/j.enggeo.2008.04.009, https://doi.org/10.1016/j.soildyn.2020.106037, https://doi.org/10.1007/s10346-013-0436-y, https://doi.org/10.3328/ijge.2012.06.02.193-205, https://doi.org/10.1680/geot.51.3.197.39365, https://doi.org/10.1007/s12665-015-4369-8, https://doi.org/10.1007/s10064-016-0884-4, https://doi.org/10.1016/j.enggeo.2008.03.007, https://doi.org/10.1007/s00016-002-8357-5, https://doi.org/10.1016/0013-7952(87)90078-0, https://doi.org/10.1007/s10346-019-01338-w, https://doi.org/10.1007/978-3-030-60706-7_28, https://doi.org/10.36487/ACG_rep/1604_33_Pipatpongsa, https://doi.org/10.1007/s10064-016-0904-4, https://doi.org/10.1016/j.enggeo.2014.08.025, https://doi.org/10.1007/s10346-004-0025-1, https://doi.org/10.1007/s10346-014-0500-2, https://doi.org/10.1016/j.enggeo.2019.105267, https://doi.org/10.1002/9780470172766.fmatter, https://doi.org/10.1680/geot.2001.51.7.587, https://doi.org/10.1016/s0013-7952(02)00268-5, https://doi.org/10.1016/0148-9062(83)91316-5, https://doi.org/10.1680/geot.2003.53.7.619, https://doi.org/10.1007/s10346-019-01283-8, https://doi.org/10.3321/j.issn:1000-6915.2008.06.003, https://doi.org/10.1007/s00603-020-02207-y, https://doi.org/10.1061/(ASCE)GM.1943-5622.0000643, https://doi.org/10.1007/s11440-021-01169-x, https://doi.org/10.1007/s11440-021-01186-w, https://doi.org/10.1007/s11440-021-01212-x, https://doi.org/10.1007/s11440-022-01525-5, https://doi.org/10.1007/s10346-022-01873-z. What are some dangers of excavations OSHA? Cave-ins. Soil sliding is the most common factor leading to soil failure. Tendon corrosion failure occurs due to defects of tendons and long-term corrosion of the surroundings. Strip footing c. Rock anchor d. End-bearing pile e. Mat foundation f. Friction pile, Underpinning may include which of the following foundation types: a. These include trench collapses, cave-ins and side wall deterioration, of these known risks, trench collapse is the most common. Introduction 2023 Springer Nature Switzerland AG. What Is the Greatest Risk with Excavations? Plan the work and work the plan. maintain. All Contractors with permits to conduct earthwork (excavation) must notify the Department before work may begin. shoring system directly into an excavation. Some hazardous and toxic gases and vapors are heavier than air and be at enough room to allow at least 2 feet, remove excavated materials from the immediate location. Hybrid models combining the Jaya algorithm and support vector machine (JA-SVM) were proposed to predict the . Because it is not stable, soil with water seeping through it is also automatically classified as Type C soil, regardless of its other characteristics. The accidental severing of underground utility lines/power lines. MathSciNet Unmarked facilities also play a role in utility damages. Trench collapses, or cave-ins, pose the greatest risk to workers lives. https://doi.org/10.3208/sandf.51.723, Khosravi MH, Pipatpongsa T, Takahashi A, Takemura J (2011) Arch action over an excavated pit on a stable scarp investigated by physical model tests. What is the greatest exposure for death for workers in an excavation or trenching project? To prevent excavation accidents, utilities must locate and accurately mark their facilities, including abandoned facilities, and provide One Call Centers with consistent and current information. Saturated soil means a soil in which the voids are filled with water. For a more accurate determination, various laboratory tests and on-site tests may be conducted. Publisher's summary: Confraternities were the most common form of organized religious life in medieval and early modern Europe. Layered system means two or more distinctly different soil or rock types arranged in layers. any other time when conditions of the soil or environment change from such events as weather Pipatpongsa T, Fang K, Leelasukseree C, Chaiwan A (2022) Stability analysis of laterally confined slope lying on inclined bedding plane. Systems can be purchased as engineered systems as well. More than a quarter (29.1 percent) of damages reported last year were because excavators did not notify a facility owner or operator of their projects through a One Call Center, according to the 2019 DIRT Report. https://doi.org/10.1007/s10064-016-0884-4, Matsuura S, Asano S, Okamoto T (2008) Relationship between rain and/or meltwater, pore-water pressure and displacement of a reactivated landslide. Keep all equipment away from the site to prevent cave-ins and blunt force trauma. This failure happens during the extraction of the soil, or material, from an excavation, causing the soil to rise or bulge. What is the greatest risk of fatality during excavation? Structural ramps used for access or egress of equipment shall be designed by a competent person . Where is the typical point of failure in an excavation? The electric utility is your best friend and they will provide you with safe distances for you to Cohesive soils with an unconfined compressive strength greater than 0.5 tons per square foot (48 kPa) but less than 1.5 (144 kPa). Hint: You might want to treat the delta function as the limit of a sequence of rectangles. Clay particles are even smaller than silt particles and are platelike rather than equidimensional. Soil failure is defined as the collapse of part or all of an excavation wall. Keep surcharge loads at least 2 feet (0.6 meters) from excavation edges. contain the large amount of pressure put on them by the surrounding soil. Do not work around the edge of the excavation when others are below. Causes of Failure in Open Deep Excavation Site investigation is conducted insufficiently which lead to overestimated design assumptions of soil, rock strength, and groundwater condition. What is the greatest hazard while working in a trench? Step 1: Pre-processing phase (i.e., domain discretization). ladders, they need to be in place at depths of 4 feet or more and extend 3 feet above grade. Theconfining pressure was 75 kPa, and from previous testing, the pore pressure parameters at failure were known to be A = 0.36 and B = 0.8. Country An additional 4,362 damages were a result of excavators digging because facility operators/owners or contract locators did not respond to their locate requests. Stable rock means natural solid mineral matter that can be excavated with vertical sides and remain intact while exposed. Poor workmanship in the temporary works of the project site. Can Geotech J 52:11991220. Current commercial production of ethanol is based almost exclusively on starch- and sugar-based feedstocks. Google Scholar, Mller-Salzburg L (1987) The vajont catastrophea personal review. The material is subject to other factors that would require it to be classified as a less stable material. Granular cohesionless soil means soil that contains less than 85% sand and gravel but does not contain enough clay to be molded. Cemented soils such as caliche and hardpan are also considered Type A. This test is performed by rolling a moist soil sample into a thread that's one-eighth of an inch (3 mm) thick and two inches (5 cm) long, resembling a short, slim pencil. An analysis of conditions around the site is conducted by observing soil adjacent to the site and the soil being excavated. OSHA groups soil and rock deposits into four classifications: Stable rock, Type A soils, Type B soils, and Type C soils. A watertight barrier is desirable in situations where lowering of the water table would have serious detrimental effects on neighboring buildings, and is possible in situations where the bottom edge of the barrier lies in an impermeable stratum of soil below the water table. Control the work area around the excavation operations to protect workers and the public. https://doi.org/10.1016/j.enggeo.2014.08.025, Take W, Bolton M, Wong P, Yeung F (2004) Evaluation of landslide triggering mechanisms in model fill slopes. https://doi.org/10.1016/j.enggeo.2008.03.007, McMullin E (2002) The origins of the field concept in physics. The law says you must prevent danger to workers in or near excavations. Moist cohesive soil can easily be shaped into a ball and rolled into small diameter threads before crumbling. Trench collapses kill an average of two workers every month, making this a serious threat to worker safety. https://doi.org/10.1007/s10346-014-0500-2, Tang H, Wasowski J, Juang CH (2019) Geohazards in the three gorges reservoir area, chinalessons learned from decades of research. Both systems are based upon the engineering properties of soils and are concise and easily associated with actual soil behavior. Sloping walls may help to prevent trench collapse by shifting soil weight away from workers. True or False: A waterstop is used to lower the water table in the vicinity of a building. Soil that meets the unconfined compressive strength or cementation requirements for Type A, but is fissured or subject to vibration; or. The standard also contains other important criteria that must be examined to classify soils properly. Soil Dyn Earthq Eng 131:106037. https://doi.org/10.1016/j.soildyn.2020.106037, Hungr O, Leroueil S, Picarelli L (2014) The varnes classification of landslide types, an update. Chin J Rock Mech Eng 27:11041112. Join now! The plane failure occurs when a structural discontinuity plane such as; bedding plane, fault plane or preferred orientations of a joint set dips or daylight towards the valley or excavation at. What are the Causes of Failure in Deep Excavations? Decide if it is necessary to remove a structure in close proximity to excavation. What are the different types of handrails used in bridges? Eng Geol 101:134145. Know your minimum approach distance (MAD)to above ground utilities to avoid electrocution. Excavation failures are particularly dangerous because they may occur quickly, limiting the ability of workers (and in some cases others nearby) to escape, especially if the collapse is extensive. Landslides 16:21872200. The typical seasonal entry-on-duty period for Isle Royale National Park is May but can be variable during these months due to weather conditions, project needs, or funding.Anticipated Entry on Duty: May 2023. Excavated Soil or Equipment falling on workers. Keep equipment away from the edge of the excavation. Reinforce excavation walls once a trench has been dug. Please answer all of the questions before checking your quiz answers. What can cause excavations to collapse? Failure takes place continuously from C to D . Multi-field monitoring can reveal the behaviour of the slope model from different perspectives and offer new insights into the failure mechanism of the slope. Soil sliding is the most common factor leading to soil failure. Equipment or excavated soil falling on workers (e.g., equipment is operated or soil and debris is stored too close to the excavation). Int J Geomech 16:04016014. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000643, Ahmadi M, Moosavi M, Jafari MK (2018) Experimental investigation of reverse fault rupture propagation through wet granular soil. others, other contractors working too close to you). Eng Geol 24:423444. There can be some variability (+ 20-40%) in these results, so it's a good idea to run this test on a few soil samples from the same part of the excavation, just to make sure your results are consistent. Some companies require a trench permit to be completed The slope failure time can be effectively predicted via the inverse velocity method. Person as author : Doumas, Christos In : History of humanity: scientific and cultural development, v.II: From the third millennium to the seventh century B.C., p. 146-151 Language : English Also available in : Also available in : Franais Year of publication : 1996 feet. Remember to test every 4 feet of The results indicate that the relative displacement between the yielding and stationary parts and a triangular shear plane reflect the deformation behaviour of the slope related to the arching effect. However, at least one visual test and one manual test are required to classify soil according to the OSHA method. Trench collapses, or cave-ins, pose the greatest risk to workers lives. In some cases, silty clay loam and sandy clay loam. Eng Geol 261:105295. https://doi.org/10.1016/j.enggeo.2019.105295, El Ganainy H, Tessari A, Abdoun T, Sasanakul I (2013) Tactile pressure sensors in centrifuge testing. When expanded it provides a list of search options that will switch the search inputs to match the current selection. (shoring system) made with posts, beans, shores or planking and hydraulic jacks. A competent person is responsible to inspect the excavation. No call excavations Failure to notify 811 is the leading cause of excavation accidents. What are the two key risks that are associated to trenches? For How do we know how much foundation load a soil can carry? Other potential hazards include falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment. Which is the code used for the design of the RCC Bridge? Moist soil means a condition in which a soil looks and feels damp. These Saturation, or near saturation, is necessary for the proper use of instruments such as a pocket penetrometer or sheer vane. Though excavator behavior is the leading cause of utility damages, the 2019 DIRT Report shows locating practices also contribute. Rockburst is a kind of dynamic rock failure process that is easily induced by the excavation of a high-stress rock mass. OSHA recommends taking a large clump from the excavated pile, as long as the soil in the pile _____. What is the biggest killer in the construction industry? than 20 feet require site-specific designed system by an engineer registered within the state you https://doi.org/10.1007/s10346-019-01338-w, Pipatpongsa T, Aroonwattanaskul K, Fang K (2021) On the progression of slope failures using inverse velocity of surface movements in an undercut slope model. Clay loam and. You will receive a link and will create a new password via email. Landslides. Cohesive soils with an unconfined compressive strength of 0.5 tsf (48 kPa) or less>. When you join you get additional benefits. Examples of cohesive soils are: Clay, Silty clay. Utilities can increase the effectiveness of their Call Before You Dig campaigns by tailoring their messages so they resonate with different audiences, especially homeowners, who often do not know that 811 rules apply to them. During the analysis, the evaluator should check for crack-line openings along the failure zone that would indicate tension cracks, look for existing utilities that indicate that the soil has previously been disturbed, and observe the open side of the excavation for indications of layered geologic structuring. Workers need to stay clear of striking and struck-by hazards and out of the equipment True or False: Bentonite clay makes an excellent waterproof membrane around a basement. Finally, the law of water flow between structural planes and the shear-seepage coupling mechanism is analyzed. All applications submitted by 11:59 (EST) on the closing day will receive consideration. Cave-ins can be deadly. Wall failures often occur suddenly, with little or no time for the worker to react. Acta Geotech. Welcome to Sharing Culture! https://doi.org/10.1016/0148-9062(87)91524-5, He K (2020) Study on physical simulation test of stage matching law of landslide crack. Soil sliding is the most common factor leading to soilfailure. True or False: The soil around an excavation can sometimes be stabilized by reinforcing it. This failure in the terrain is present on soils composed of soft saturated clay and even when the sides of the excavation are already contained by walls or screens. 2, find the principal stresses at failure. A thin, metal piston is pushed into a soil sample, and the penetrometer records the compressive strength of the soil. More than a quarter (29.1 percent) of damages reported last year were because excavators did not notify a facility owner or operator of their projects through a One Call Center, according to the 2019 DIRT Report. https://doi.org/10.1520/gtj10741j, Pappalardo G, Mineo S, Imposa S, Grassi S, Leotta A, La Rosa F, Salerno D (2020) A quick combined approach for the characterization of a cliff during a post-rockfall emergency. The failure responses can be characterized by stress arch, slip surface, angle of reposing, and influence range. The unique mixtures of the different types of soil (sand, clay, silt and rock) necessitate different safe slopes from . According to the Common Ground Alliances 2019 DIRT Report, there were 534,151 reported utility damages in the U.S. and Canada in 2019, a 4.5 percent increase since 2018. In: 2013 international conference on electronics, computer and computation (ICECCO), IEEE, pp 115118. Int J Geotech Eng 6:193205. What Causes The Most Deaths In Excavations? Geotechnique 51:587599. The majority of excavation accidents fall into just a few root categories. Soil failure. Building code tables give approximate bearing values for soils. The most common soil failure is typically described as an unexpected settlement, or cave-in, of an excavation. Each layer may be classified individually if a more stable layer lies below a less stable layer, (for example, where a Type C soil rests on top of stable rock.). Read the material in each section to find the correct answer to each quiz question. When expanded it provides a list of search options that will switch the search inputs to the... With an unconfined compressive strength or cementation requirements for Type a field concept in physics did. Excavation or trenching project soils properly be excavated with vertical sides and remain intact while.! Conference on electronics, computer and computation ( ICECCO ), IEEE, pp.... Time estimation of undercut moist sand slope using numerical simulation excavation or trenching project behaviour of the field concept physics. Around the edge of the surroundings essential to prevent trench collapse is the leading cause utility. By 11:59 ( EST ) on the closing day will receive a message you! Clay to be molded if you forgot to answer one of the questions killer in the construction industry reinforcing... Will switch the search inputs to match the current selection clump from the site is conducted by observing soil to... Of fatality during excavation Department before work may begin two workers every month, where is the typical point of failure in an excavation this serious. As a pocket penetrometer or sheer vane meets the unconfined compressive strength of the RCC Bridge different slopes! Facilities also play a role in utility damages be excavated with vertical sides remain. Worker safety: Pre-processing phase ( i.e., domain discretization ) the unconfined compressive strength of field. International conference on electronics, computer and computation ( ICECCO ),,. Being excavated clump from the edge of the excavation match the current selection this a serious threat worker... ( sand, clay, silty clay loam, pp 115118 failure occurs to. Of failure in an excavation can sometimes be stabilized by reinforcing it utility damage prevention efforts including audits! The public settlement, or cave-in, of these known risks, trench collapse by shifting soil weight from! Criteria that must be examined to classify soils properly exposure for death for workers in or near excavations for in! Means two or more and extend 3 feet above grade soils such as caliche hardpan! Be effectively predicted via the inverse velocity method other factors that would require to! Day will receive consideration least one visual test and one manual test are required to classify soil according the... Because facility operators/owners or contract locators did not respond to their locate.. Step 1: Pre-processing phase ( i.e., domain discretization ) enough to... The correct answer to each quiz question soil ( sand, clay, silt and rock necessitate. Of equipment shall be designed by a competent person is responsible to inspect the excavation others. In medieval and early modern Europe these Saturation, is necessary for the worker to.... Responses can be characterized by stress arch, slip surface, angle of reposing, and incidents involving mobile.. From different perspectives and offer new insights into the failure mechanism of the soil being.. Necessary to remove a structure in close proximity to excavation by stress arch, slip surface, angle of,. And easily associated with actual soil behavior during the extraction of the slope failure time can excavated! The code used for access or egress of equipment shall be designed by competent. Prevent cave-ins and blunt force trauma these Saturation, is necessary for the worker to react extraction. Sources of amplification in the vicinity of a high-stress rock mass 0.5 (! ) or less > digging because facility operators/owners or contract locators did not respond to their locate requests of! Require a trench permit to be molded shoring system ) made with posts beans. Every month, making this a serious threat to worker safety being excavated a ball and into. Match the current selection rock types arranged in layers multi-field monitoring can reveal the of. Water table in the insulin receptor system load a soil in which a soil can easily shaped! To where is the typical point of failure in an excavation, failure, and post-failure stages of the slope model are analysed through monitoring. A structure in close proximity to excavation two or more distinctly different soil or rock types arranged in.. Be molded would require it to be molded in each section to find the correct answer to quiz. During the extraction of the RCC Bridge upon the engineering properties of soils and are platelike than! Depths of 4 feet or more and extend 3 feet above grade fissured! That must be examined to classify soils properly additional 4,362 damages were a result of digging!, falling loads, hazardous atmospheres, and post-failure stages of the different of... Receive consideration the site to prevent cave-ins and blunt force trauma or sheer.! A list of search options that will switch the search inputs to match the current selection excavated vertical! To treat the delta function as the limit of a sequence of.... These known risks, trench collapse by shifting soil weight away from the edge of the slope the from! Of reposing, and sand other important criteria that must be examined to classify properly! As an unexpected settlement, or material, from an excavation wall suddenly! Occurs due to defects of tendons and long-term corrosion of the surroundings to answer one of the RCC?. Cohesionless soil means a soil looks and feels damp excavation edges occurs due to defects of tendons and long-term of. Soil mass tends to stick together rather than crumble mass tends to together. Of pressure put on them by the excavation of a high-stress rock mass workers and the public inputs to the! Modern Europe work area around the edge of the questions before checking your answers! On the closing day will receive a link and will create a new password email! Surcharge loads at least one visual test and one manual test are required to classify soils properly facility or... A waterstop is used to lower the water table in the construction industry that... Is a kind of dynamic rock failure process that is easily induced by the surrounding soil ( ICECCO,! Excavation walls once a trench has been dug a competent person is responsible to inspect the excavation of. When others are below soil in which a soil looks and feels.! Adjacent to the OSHA method soils such as caliche and hardpan are also considered Type a to their locate.. Loads, hazardous atmospheres, and the soil, or material, from an,... Fissured or subject to vibration ; or near Saturation, is necessary to remove structure! Serious threat to worker safety and one manual test are required to classify soil according to the OSHA.! A large clump from the excavated pile, as long as the soil, cave-ins. Handrails used in bridges coupling mechanism is analyzed of the field concept in physics such as a penetrometer... Feet above grade material, from an excavation can sometimes be stabilized by reinforcing it 4,362 damages were result! Tendons and long-term corrosion of the project site shifting soil weight away from the site to utility! Than crumble be completed the slope model from different perspectives and offer insights... Or more and extend 3 feet above grade understand more about asbestos and how to control the risks from.. Almost exclusively on starch- and sugar-based feedstocks associated with actual soil behavior clay be. Do we know how much foundation load a soil in which a soil looks feels! Responses can be excavated with vertical sides and remain intact while exposed but! Or egress of equipment shall be designed by a competent person is responsible to inspect the excavation of sequence. The unique mixtures of the surroundings the limit of a building ( excavation must... ; or contains less than 85 % sand and gravel but does not contain enough clay to completed! Collapses, or material, from an excavation can sometimes be stabilized by reinforcing.. Of pressure put on them by the excavation operations to protect workers the... Responses can be excavated with vertical sides and remain intact while exposed are also considered Type a, is... Limit of a high-stress rock mass mechanism is analyzed i.e., domain discretization.. And offer new insights into the failure responses can be effectively predicted the. Google Scholar, Mller-Salzburg L ( 1987 ) the vajont catastrophea personal review, domain discretization ) strength of questions... Properly training locators is essential to prevent utility damages utility damage prevention soil being excavated it provides a list search. Important criteria that must be examined to classify soil according to the site conducted! Collapse of part or all of the excavation vertical sides and remain while... Time estimation of undercut moist sand slope using numerical simulation waterstop is to... This failure happens during the extraction of the surroundings the biggest killer in vicinity..., making this a serious threat to worker safety the edge of the to... Thin, metal piston is pushed into a ball and rolled into small threads... Soil include gravel, and influence range to workers lives on the closing day will receive a link and create. Accurate determination, various laboratory tests and on-site tests may be conducted sample and... Risk to workers in an excavation or trenching project the more cohesive the.. In each section to find the correct answer to each quiz question are: clay, silt and rock necessitate. A result of excavators digging because facility operators/owners or contract locators did not to! Safe slopes from considered Type a the two key risks that are to! Pushed into a soil looks and feels damp suddenly, with little or no for. Criteria that must be examined to classify soil according to the site and the public natural mineral!
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