lithosphere and groundwater lithosphere w solid rocky crust of the earth w rocks on the surface are...

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Lithosphere and Groundwater

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Lithosphere and Groundwater

Lithosphere solid rocky crust of the earth rocks on the surface are

classified in 3 types igneous-cooled, molten rock,

granite

Lithosphere Sedimentary- sediments deposited

in water and later made solid. Metamorphic-Igneous and

sedimentary rocks changed by hear &/or pressure Ex: marble, slate

Groundwater groundwater- water occurring

beneath the surface used mostly as well water most occurs within lithosphere water table- the surface of ground

water in a well

Groundwater point in the ground that is

completely saturated with water.

Water fills all spaces between soil and rock particles. (pores)

Groundwater Porosity- portion of the ground

that contains spaces or voids. The total porosity of the material and size and continuity determine the volume of groundwater that is held available.

Groundwater U.S. gets 1/2 of our drinking

water from groundwater

Groundwater Groundwater pollution 1988- EPA published a report 46 pesticides found in

groundwater in 26 states only 9 were in concentrations

higher than health advisory levels

Groundwater World Health Organization

(WHO) each year 1/2 million people are poisoned by pesticides

Groundwater Herbicides & Insecticides are

used in “large quantities” by farmers- one billion pounds of active ingredient per year

Groundwater Nitrates- EPA standard of no

more than 10mg/liter of Nitrate Nitrogen in groundwater used for drinking.

More than 21% of samples contained more than 10mg per liter in Kansas and Rhode Island

Groundwater 10-19% were in excess in

California, Arizona, Oklahoma, and New York

5-9% were in excess in Colorado, South Dakota, Nebraska, Texas, Minnesota, Iowa, Illinois, Pennsylvania, Maryland, and Delaware

Groundwater in all of the other 50 states less

than 5% tested high.

Controlling Groundwater pollution 1990 National Fertilizer and

Environment Research Center set up 20 demo sites to control pesticide and nitrate pollution.

Pierre, South Dakota Cone Ag Service

Problems of greatest concern metallic impurities in

phosphoric acid fertilizer gypsum pond leakage treatment of contaminated soil reducing pollution from liquids

rinsed from application equipment

Problems of greatest concern

microbial techniques for waste treatment

nitrate inhibitors for area techniques for sampling and testing

groundwater developing better containments for

chemigation and fertigation

Pesticides and groundwater most pesticides are synthetic

organic compounds

Processes for loss from soil volatilization decomposition retention by soil transport by H2O

Fumigants relatively volatile vaporize at low temperature and

move as gases through the soil Ethylene dibromide - used for

nematode control

Ethylene dibromide very soluble in water not retained by soil commonly found in ground

water

Synthetic Organics may be decomposed in different

ways many are broken down rapidly

in sunlight

Some pesticides react in water to form new

compounds fungicide Captan reacts rapidly

with water to form a hamless product

Some chemicals decompose very slowly and

may persist for years example - DDT

Organic Matter is the most important soil

particle in binding pesticide in the soil rather than going into the water

Primary transport of pesticides through the soil is

by percolation of water down

Health Advisory Concentrations each of two animals is treated with

a range of doses of the pesticide maximum dosage that produces no

adverse effects in the more sensitive of the two species is divided by a safety factor (100)

Concentrations for a substance for which a safety

factor of 100 has been used a 22 pound child would have to

drink 26 gallons of water with the health advisory concentration per day every day

Continued to ingest an amount of pesticide

equivalent to the max daily intake that produced no observable effect in the test animal of the same average weight

Avoiding pesticides in h2o alternative h2o sources distilling h2o ultraviolet light activated carbon filter

Nitrates and groundwater mostly from plant fertilizers introduction of legumes

(alfalfa) plants that take Nitrogen from

the air and put it into the soil

Nitrates and groundwater commercial fertilizers are used

to supplement naturally occurring nutrients

production of ag crops has increased due to the use of fertilizers

Nitrates and groundwater plants absorb only part of each

nutrient present in the soil as the concentration of nutrients in

the soil increases, % of total amount absorbed decreases

greater residues are left in the soil

Nitrates and groundwater most chemical ions of fertilizers

are bonded to and retained by the soil

Nitrogen is not

Human Health Issues Problems related to Nitrates birth defects cancer migraines

Human Heath Issues nervous system impairment methomoglobinemia

Methomoglobinemia type of anemia hemoglobin carried Nitrogen

instead of Oxygen to the body cells

common cause of infant deaths

Groundwater use over drafts when more water is removed

than is replaced by water from the surface

57% of water resource regions have over drafts

Groundwater use water table is falling in these areas most serious over draft is at the

Ogallala Aquifer nations largest under parts of 8 states