EPCR-2012Environmental Pollution : Challenges and Remediation Presented by: Preksha Bhardwaj Shikhar Sodhani Vivekananda Institute of Technology, Jaipur.
WATEROccurrence of water1. 97% of all water on earth is in oceans.2. ~ 2% of the earths water in ice caps & glaciers3. About 0.6% of earths water is groundwater4. Water in rivers, lakes, and the atmosphere amounts toless than 0.02% of earths water .
GROUNDWATERWater is a basic necessity for the life tosustain.Ground water is the water located beneath theearth’s surface in soil pore spaces and infractures of rocks.It serves intensively for irrigation and industrialpurposes (50%).Ground water is an integral part of thehydrological cycle and its availability dependson the rain and recharge conditions.
Aquifers(Saturated Zones):Aquifers are underground layers of permeablerock, gravel, sand or clay that water can be extractedfrom.When the spaces are large enough to containusable quantities of water, it is called an aquifer.There are two types of aquifers: 1. Confined 2. Unconfined A confined aquifer has a layer of impermeable clay or bedrock above it, as well, and an unconfined aquifer does not.
Groundwater movement:Groundwater moves slowly from recharge areas todischarge points.Flow rates are faster in cracks of rocks or veryloose soil but in dense soli of fine particles it movesvery slowly. Groundwater generally moves in parallel paths orlayers.
Cone of DepressionRemoving water from the well lowers the water tableresulting in the formation of Cone of Depression.The effect of cone of depression extends to thenearby water bodies known as InducedRecharge.
Groundwater is the major source of water in our country with 85% of the population dependent. Groundwater table declines-33cm/year.
Depleting Water Table Fast growing cites Rapid rise in demand of water Requirement of imported water (water from various water bodies) is increasing at an alarming rate Depletion in Groundwater level(Water Table)
GROUNDWATERCONTAMINATION Groundwater pollution is a change in the properties of groundwater due to contamination by microbes, chemicals, hazardous substances and other foreign particles. It is a major type of water pollution.
Ground Water PollutionThe sources of groundwater pollutants are either natural(mineral deposits in rocks) or man-made.Natural sources are less harmful compared to hazardouschemicals generated by human activities.Any chemical present on the surface can travelunderground and cause groundwater pollution. The seepage of the chemical depends on the chemicaltype, soil porosity and hydrology.>70,000 chemicals are used not; effects of many are notknown. Each year another 700-800 new chemicals are produced.
Some Sources:Groundwater contamination can come from a number of naturaland human-made sources. Thesecan include:1. Leaks and spills at factories and commercial facilities.2. Improper hazardous waste disposal.3. Improper use and disposal of pesticides.4. Leach ate from landfills.5. Septic systems.6. Saline Intrusion.7. Salts and chemicals used to deice roads.8. Liquid waste storage lagoons9. Fertilizers10. Animal wastes11. Leaking underground storage tanks12. Radon contamination13. Underground injection wells14. Pipeline breaks
A bit description…… Arsenic contamination- Arsenic is a deadly chemical that is often found in a contaminated area. Arsenic is naturally occurring, but when chemical contamination increases the concentration it becomes dangerous. Arsenic poisoning can be linked to skin, lung and bladder cancer. High levels of arsenic also lead to cardiovascular damage. radon contaminatiion-Soil made up of granite rock, some volcanicrock, organic-rich shales, phosphate mineralsor pitchblende is known to release radon.
GROUNDWATER DEPLETION•The amount of water pumped byfarmers from India’s aquifers isgreatly exceeding natural rechargein many areas.•In the western part of the Indo-Gangetic Plain, where therecharge approach described herewas initiated•rainfall ranges between 650 and1,000 mm annually, but only 200mm naturally percolate throughthe soil layer to replenishunderlying aquifers.
Recharge of Groundwater:•Groundwater recharge is the replenishment of an aquifer withwater from the land surface.•The amount of water that may be extracted from an aquiferwithout causing depletion is primarily dependent upon the groundwater recharge.•Water is continually recycled through aquifer systems.• Groundwater recharge is any water added to the aquifer zone.• Processes that contribute to groundwater recharge includeprecipitation, stream flow, leakage (reservoirs, lakes,aqueducts), and artificial means (injection wells).
Rainwater harvesting is the accumulating and storing of rainwater for reuse before it reaches the aquifer. •In urban area rainwater The principle of collecting and using flows away as surface precipitation from a catchment surface. There are two ways for harvesting runoff. This runoff could be1. Surface runoff harvesting used to caught and used2. Roof top rainwater harvesting for recharging aquifers by We use surface run off harvesting to increase adopting appropriate the groundwater table. methods. •Harvesting of surface runoff and storage of the same into reservoirs such as water pans makes it available for use when required.
SUB-SURFACE DYKES It is a subsurface barrier across stream which retards the base flow and stores water upstream below ground surface. Since the water is stored within the aquifer , submergence of land can be avoided and land above the reservoir can be utilized even after the construction of the dam. No evaporation loss from the reservoir and no siltation in the reservoir take place. The potential disaster like collapse of the dams can also be avoided.
Crosswave plastic material CROSS-WAVE is a material of underground rainwater storage for a Rain Water Harvesting developed by a Japanese company SEKISUI TECHNO MOLDING CO.LTD. It creates space underground for water in high void ratio which contributes to the effective use of rainwater and control overflow. The underground water space created by CROSS-WAVE controls flood of river and drainage caused by heavy rain, at the same time providing the environment through which stored rain water can be utilized according to necessity. This reserved water can be used for daily life usage or industrial usage and at the time of emergency.
Construction procedureAs CROSS-WAVE is light weight so transportation is alsosmooth.Heavy load capacity, strong enough for 25t truck withcovering more than 60cm.Can be install simply by cross and piling up.Apart from that you can utilize for wide range of civilengineering materials such as lightweight fill materials ortemporary construction material.
Installation sitesFlood Control Controlling overflow in a redevelopment area. By making some underground reservoirs at redevelopment area ,rainwater runoff in the can be reduced. Can be used at: •Under park at redevelopment area •Under parking lots at shopping center
Installation sitesRainwater Harvesting Water for life, industry and irrigation CROSS-WAVE has miscellaneous uses It can be used for various purposes such as water for car washing, irrigation ,industrial usage and for gardens. Can be used •Under parking lots at personal house, hospital and office •Under parking lots at plant •Under farm road or green house
Installation sitesFire Fighting Water storage for fire fighting and disaster CROSS-WAVE can be applied from 40 ton to 10000m3 and can store for emergency water supply. Can be used •Under park •Under schoolyard
Installation sitesDaily use water Water for fountain or small stream Use rainwater for fountain on small stream then you can develop hydrologic cycle that enrich your life. Can be used •Around park or amenity space •Under parking lots at housing complex
Installation in IndiaStorage tank for factory in Chennai, India (Storage capacity:20m3)