Environmental Issues and Education Needs

Written by Editor
TAMANNA KALIM


This provides an initial assessment of the overarching environmental health and infrastructure issues faced by New Orleans to rein habit the city. It was prepared by a joint taskforce of the Centers for Disease Control and Prevention (CDC) in the Department of Health and Human Services (DHHS) and the U.S. Environmental Protection Agency (EPA). EPA and CDC are collaborating with state and local public health and environmental officials, including the New Orleans City Public Health Department, the Louisiana Department of Health and Hospitals, and the Louisiana Department of Environmental Quality.

Officials will need to attend to the environmental health and infrastructure issues identified in the report. EPA and CDC are committed to collecting and providing scientific data to decision makers and the public. However, the data are limited and conditions in the storm-damaged areas of the City are constantly changing. Consequently, significant additional risks may arise that do not exist currently. A wide variety of factors are driving the decision to reopen portions of the City, and many precautions beyond those mentioned in this report need to be taken. State and local leaders are advised to consider the potential hazards, caution returning inhabitants of the health risks, and provide for sufficient medical and other resources to address the returning population in light of existing conditions.

CDC and EPA are neither responsible for addressing all of the environmental health and infrastructure issues identified in the report nor for coordinating resources to attend to them. Furthermore, the report is neither a step-by-step guide nor a guidance document with criteria for rein habiting the city.

The report identifies a number of barriers to overcome and critical decisions to make prior to reinhabiting New Orleans. CDC and EPA are not implying that it is our role to wholly attend to these barriers or make these decisions. These decisions will be made by the mayor and city officials in consultation with the authorities involved in the coordinated response.

The report is focused broadly at the city of New Orleans. Some of the environmental health and infrastructure issues discussed in the report may not apply to the less flooded and damaged neighborhoods in New Orleans. As a result, the decision to reinhabiting New Orleans must be made neighborhood-by-neighborhood and requires a deliberate neighborhood-level analysis. Also, the decision to reopen a neighborhood must consider the impact of returning residents on the broader recovery and redevelopment activities for the whole city.

Everyone is eager to restore the vibrant and unique city of New Orleans. It is our hope this report will highlight some of the cross-cutting environmental health and infrastructure issues requiring attention to reinhabit New Orleans. However, this report should not be relied upon as a comprehensive assessment of the environmental conditions of the City of New Orleans, or of the human health risks associated with returning to reopened portions of the City.

At the request of the Secretary Michael Leavitt of the Department of Health and Human Services (DHHS) and Administrator Steve Johnson of the U.S. Environmental Protection Agency (EPA), the Director of the Centers for Disease Control and Prevention (CDC), Dr. Julie Louise Gerberding, created the Environmental Health Needs Assessment and Habitability Taskforce (EH-NAHT). The taskforce was charged with identifying the overarching environmental health issues faced by New Orleans to reinhabit the city.

The EH-NAHT collaborated extensively with a diverse group of federal, state, and local partners, including the New Orleans City Public Health Department, the Louisiana Department of Health and Hospitals (LADHH), and Louisiana Department of Environmental Quality (LDEQ), Federal Emergency Management Agency (FEMA), and U.S. Army Corps of Engineers (USACE).

The team was guided by the following questions:

  • What is the core or fundamental environmental health issues to be addressed?
  • Which agencies and organizations at the federal, state, or local level are responsible for, or involved in, the various environmental health issues?
  • What progress has been made and what challenges exist?
  • What is the timetable to address these environmental health issues?
  • What resources exist or need to be brought to bear to address these environmental health issues?
  • What are the key milestones and endpoints that define success?

The team identified 13 environmental health issues and supporting infrastructure to address. This initial assessment included drinking water, wastewater, solid waste/debris, sediments/soil contamination (toxic chemicals), power, natural gas, housing, unwavering/flood water, occupational safety and health/public security, vector/rodent/animal control, road conditions, underground storage tanks (e.g., gasoline), and food safety.

After the initial assessment, the EH-NAHT categorized these issues by increasing time and complexity to full restoration of services (Level 4, most complex and requiring the most time to restoration). Part of the complexity relates to how specific and explicit the criteria for the end points are for each function.

Level 1Level 2Level 3Level 4
Unwatering
Power
Natural Gas
Vector/Rodent/Animal
Control
Underground storage
tanks (e.g., gasoline)
Food Safety
Drinking Water
Wastewater
Road Conditions 
Solid
Waste/Debris
Sediments/Soil Contamination (Toxic Chemicals)
Housing
Occupational safety and health as well as public security was identified as cross-cutting all the other areas.

Long-term solutions to these many issues are critical to allow resumption of normal life in New Orleans and to prevent reoccurrence of such an event in these areas:

1) Problem realization
2) Know the cause and nature of the problem
3) Necessity for conservation of world’s natural resources
4) Prediction of the problem and solution
5) Better environment for the next generation.

Local Environmental Issues



Natural Environmental Issues

1.Ozone Depletion
Causes

  • Use Of CFC Gas
  • Damage In Ozone Layer

Problems

  • Skin Cancer
  • Optical Disease
  • Decrease The Power Of Reproductive Organ

Solution

  • The use CFC, Chlorine, Carbon and other waste materials should be prohibited by effective law.


2.Arsenic

The groundwater arsenic problem in Bangladesh arises because of an unfortunate combination of three factors: a source of arsenic (arsenic is present in the aquifer sediments), mobilisation (arsenic is released from the sediments to the groundwater) and transport (arsenic is flushed away in the natural groundwater circulation).

Geological source of arsenic

Previously a number of anthropogenic explanations had been for the occurrence of arsenic in groundwater.  While it is possible that some may explain isolated cases of arsenic contamination, none of the anthropogenic explanations can account for the regional extent of groundwater contamination in Bangladesh and West Bengal.  There is no doubt that the source of arsenic is of geological. The arsenic content of alluvial sediments in Bangladesh is usually in the range 2-10 mg/kg; only slightly greater than typical sediments (2-6 mg/kg). However, it appears that an unusually large proportion of the arsenic is present in a potentially soluble form. The high groundwater arsenic concentrations are associated with the grey sands rather than the brown sands.

There is a good correlation between extractable iron and arsenic in the sediments and a relatively large proportion (often half or more) of the arsenic can be dissolved by acid ammonium oxalate, an extract that selectively dissolves hydrous ferric oxide and other poorly ordered oxides. It therefore appears likely that a high proportion of the arsenic in the sediments is present as adsorbed arsenic. This would not be true of arsenic present in primary minerals such as arsenic-rich pyrite.

The greatest arsenic concentrations are mainly found in the fine-grained sediments especially the grey clays. A large number of other elements are also enriched in the clays including iron, phosphorus and sulphur. In Nawabganj, the clays near the surface are not enriched with arsenic to any greater extent than the clays below 150 m – in other words, there is no evidence for the weathering and deposition of a discrete set of arsenic-rich sediments at some particular time in the past. It is not yet clear how important these relatively arsenic-rich sediments are for providing arsenic to the adjacent, more permeable sandy aquifer horizons. There is unlikely to be a simple relationship between the arsenic content of the sediment and that of the water passing through it.

It is likely that the original sources of arsenic existed as both sulphide and oxide minerals. Oxidation of pyrite in the source areas and during sediment transport would have released soluble arsenic and sulphate. The sulphate would have been lost to the sea but the arsenic, as As(V), would subsequently have been sorbed by the secondary iron oxides formed. These oxides are present as colloidal-sized particles and tend to accumulate in the lower parts of the delta. Physical separation of the sediments during their transport and reworking in the delta region has resulted in a separation of the arsenic-rich minerals. The finer-grained sediments tend to be concentrated in the lower energy parts of the delta. This is likely to be responsible for the greater contamination in the south and east of Bangladesh. The map of arsenic-contaminated groundwater shows that highly contaminated areas are found in the catchments of the Ganges, Brahmaputra and Meghna rivers strongly suggesting that there were multiple source areas for the arsenic.

The types of sediment deposited in the delta region have been strongly influenced by global changes in sea level during the Pleistocene glaciations. For example, sea level was more than 100 m lower at the peak of the last lee Age around 18,000 years ago. At that time the major rivers cut deeply incised valleys into the soft sediments of the delta. All of the highly contaminated ground waters occur in sediments deposited since that time, while those sediments predating the low sea level stand contain little or no arsenic-contaminated groundwater.

Mobilization of the arsenic – redox processes

Burial of the sediments, rich in organic matter, has led to the strongly reducing groundwater conditions observed. The process has been aided by the high water table and fine-grained surface layers which impede entry of air to the aquifer. Microbial oxidation of the organic carbon has depleted the dissolved oxygen in the groundwater. This is reflected by the high bicarbonate concentrations found in groundwater in recent sediments. There is a relationship between the degree of reduction of the groundwater and the arsenic concentration – the more reducing, the greater the arsenic concentration.

The ‘pyrite oxidation’ hypothesis proposed by scientists from West Bengal is therefore unlikely to be a major process, and that the ‘oxyhydroxide reduction’ hypothesis (Nickson, R. et al. 1998 in Nature v395:338) is probably the main cause of arsenic mobilization in groundwater. It is difficult to account for the low sulphate concentrations if arsenic had been released by oxidation of pyrite. Moreover, mineralogical examination suggests that the small amounts of pyrite present in the sediments have been precipitated since burial.

Transport of arsenic within the aquifers

Present groundwater movement is very slow because of the extremely low hydraulic gradients found in the delta region. Except where modified by pumping, groundwater circulation is largely confined to the shallow layers affected by local topographic features and the presence of rivers. Close to rivers, the enhanced groundwater flow may lead to a greater dispersion of arsenic along river banks. Annual fluctuations of the water table, typically about 5 m, will affect groundwater and arsenic movement in the shallow layers. There may have been some flushing of arsenic from the shallowest layers.

At greater depths, groundwater moves slowly in response to the low regional gradients. This is consistent with the old age of the waters. The lateral and vertical spread of contaminants is slow even without considering the retardation due to sorption. Modeling suggests that even in the most permeable layers, arsenic movement is likely to be limited to a few meters a year.

The permeability of the silt clay layers is low and in the case of a narrow horizon of silt clay, water will preferentially move through the adjacent more permeable sandy layers. This effectively protects the silt clay layers from strong leaching and possibly preserves arsenic-rich zones. This relative lack of water and arsenic movement and the strong stratification of the aquifer therefore both preserve the high concentrations of arsenic from leaching and lead to the great spatial variability observed. The conclusion from this is that in the absence of man’s intervention significant short-term (less than a few decades) variations in arsenic concentrations are unlikely to occur at depth.

The mitigation strategy

Many national and international organizations are looking into how to overcome the arsenic problem and the World Bank has recently announced that an initial $44 million loan will be made available to the Government of Bangladesh to begin to tackle the problem. The task ahead is enormous and it is clear that there is not going to be a single, simple solution for all of Bangladesh.

There are many options inter alias including: use of surface water with treatment by pond sand fitter; sinking deep wells into the arsenic-free aquifers; rain water harvesting; ring wells to tap the very shallow aquifer; solar-assisted oxidation and sterilization of existing groundwater; and Arsenic treatment at various scales.

The challenge is partly technical – to design systems that work reliably and that are both acceptable and affordable in rural Bangladesh. But the problem also throws up many institutional challenges.

The solution must be organised by the rural communities themselves and this is going to require a massive educational programme. Above all, the scale of the problem makes implementing even a simple solution very demanding. There are almost certainly more than half a million wells affected. The problem is clearly a long term one but also demands immediate, emergency action.

It was not the purpose of this study to devise a mitigation strategy – many others are already doing that – rather we hoped to inform those devising such a strategy. Below we draw attention to some of the findings of this study that may be helpful in this regard and particularly in selecting priorities for the emergency action programme.

Regional differences in the extent of contamination clearly shows large differences in the extent of contamination of the shallow tube wells in different districts from ‘hardly affected’ in the north-west to ‘nearly all affected’ in the south east.

Four classes of contamination and corresponding strategies can be defined for the shallow aquifer: low contamination (less than 10% of wells) areas where occasional ‘hot spots’ are possible. The ‘omission’ of Chapai Nawabganj in the randomly based Regional Survey highlights the difficulty of locating all of these. Although these areas may receive lower priority for comprehensive testing, a more efficient approach might be to conduct more intensive randomized sampling across these areas, supplemented by local comprehensive surveys as and when hot-spots are located.;

Medium contamination (10-60%): extensive, preferably comprehensive, testing will be required especially in the western region and in the north-east where the pattern of contamination appears to be rather patchy; high contamination (greater than 60%): two approaches are possible. Either the areas can be considered so highly contaminated that the future effort should concentrate on mitigation rather than further testing or use further testing to locate the minority of safe wells and then use only these. Much depends on what other options are available locally.

Shallow saline groundwater also contaminated by arsenic: there is no problem with shallow wells in these areas because the water is too saline to drink anyway. Deep wells are used in the south of Bangladesh to avoid this problem and these have a very high probability of being safe. However, all new wells should be tested before commissioning.

The future of groundwater use in Bangladesh

The discovery of severe arsenic contamination of groundwater in large parts of Bangladesh came as a shock to all concerned. It affects about a third of the wells in the Regional Survey area and perhaps a quarter of wells in the country as whole. More than 20 million people are probably drinking water that exceeds the Bangladesh standard. The Government takes the problem extremely seriously, and donor agencies have pledged to assist.

Understandably, there has been something of a media backlash against the use of groundwater. There have even been calls to abandon the use of groundwater completely. Less radical proposals call on a moratorium on all new government- or donor-sponsored drilling for a year or so until the situation is clearer.

Amidst this debate, it must not be forgotten that most wells are not contaminated and that large parts of northern Bangladesh are hardly affected at all. In these areas, there is no reason why the benefits that exploiting groundwater has brought to Bangladesh should not continue. A rapid and widespread return to the use of surface water would inevitably result in an increase in diarrhoeal disease.

The situation calls for a pragmatic combination of practical, affordable and sustainable short, medium and long-term water supply programmes aimed at minimizing the combined risk to health of diarrhoeal disease, arsenic and other natural and man-made chemicals that may be present in the environment.


Man-made Environmental Issues
1.Deforestation
Cause
– Destructions of forests
– Unlimited Wastage of forest resources
Problems
– Loss of Ecosystem
– Extinction of Species
– Flood
Solution
– Forest conservation
– Forestation and reforestation

2.Persistent organic pollutants
Cause
– food color preserver
– industrial waste
– chemicals, (such as: Hg, Cd, Pd)
Problems
– cancer
– birth disease
– physical and mental disorder
– Extinction of birds for thin egg cell.
Solution
– Effective measures should be taken by governmental and non governmental level.

3. Loss of bio diversity
Cause
– Loss of ecosystem
– Loss of species diversity
– Loss of genetic diversity
Problems
– Habitant conservation
– Large ecosystem into small
– Over exploitation of species.
Solution
– The diversity of species genetically and ecologically should conserve.

Global Environmental Issues
1) Ozone Layer Depletion

What is ozone: Ozone is a bluish, very reactive gas, whose molecule is made by three oxygen atoms. (In the NASA image, one ozone molecule is formed through the collision of an oxygen atom with one bionomic oxygen molecule). Nearly 90% of the Earth’s ozone is situated in the stratosphere, the atmosphere layer between 10 to 40 kilometers above Earth’s surface, where it is continuously generated and destroyed by the UV radiation. Only a minor part of ozone is in the troposphere, the internal atmospheric layer, where the meteorological phenomena occur. Troposphere ozone is mainly produced by photochemical reactions involving other pollutant gases, especially over large cities.

How can be ozone dangerous?

The thin layer (NASA image) of ozone gas in the stratosphere (ozone layer) is shielding life on earth from the harmful UV light coming from the sun (“good ozone”). Ozone is harmful at earth level, being very reactive and irritant to the human eyes (the so-called “bad ozone”).


Is ozone layer threatened?

The overall amount of ozone is essentially stable in a natural cycle. This has been true for millions of years. Since some decades, according to atmospheric measurements, ozone layer is getting thinner. Ozone depletion has been most severe at the poles, especially over Antarctica, where a seasonal ozone layer “hole” appears (in the NASA image the blue color means lack of ozone).

The Antarctic ozone hole was discovered in 1985 by British scientists: it is not technically a “hole” where no ozone is present, but is actually a region of exceptionally depleted ozone in the stratosphere over the Antarctic that happens at the beginning of Southern Hemisphere spring (August-October). An endlessly circling whirlpool of stratospheric winds called the “polar vortex” isolates the air over Antarctica in winter. The ozone hole grows throughout the early spring until temperatures warm and the polar vortex weakens, ending the isolation of the air. As air from the surrounding latitudes mixes into the polar region, the ozone layer stabilizes until the following spring.

What are the effects of the reduction of the ozone layer?

The reduction of ozone layer will cause an increase of UV radiation at earth level. An excess of UV rays has been linked to skin burns, skin cancer, cataracts, and harm to certain crops and marine organisms.

What is being done to stop ozone depletion?

Replacing the CFCs and other ozone depleting substances with environmentally safe substances is necessary to stop ozone depletion. Researches are going on for identifying the best alternative substances; presently HCFCs (hydro chlorofluorocarbons, substances containing hydrogen, chlorine, fluorine, carbon) are replacing CFCs, being much less harmful for the ozone layer. In the future, HCFCs will be phased out, too.

Montreal Protocol
“Montreal Protocol” is the 1987 international treaty governing the protection of stratospheric ozone agreement to phase out the Ozone Depleting Substances. According to the Montreal Protocol (and successive amendments) usage of the CFCs and most Halons have been reduced or phased out; other ODS, like HCFCs, will be phased out in the future.

Montreal Protocol was without doubt a great success for the environment, clearly reducing the total amount of chlorine and bromine entering the atmosphere. Those reductions should first arrest the decline, and then allow the ozone layer to rebuild. Anyway, even if the consumption of all ODS gases would be completely discontinued; it will take a lot of years before complete recovering of the ozone layer, due to their persistence in the atmosphere.

2) Green House Effect

Some gases in the atmosphere produce the “greenhouse effect”, trapping the heat of Earth without allowing it to escape in the outer space.

The greenhouse effect is normally natural and beneficial: without it Earth would be at least 15 ° C colder; it is becoming more and more important due to the increasing concentration of these gases (“greenhouse gases”) in the atmosphere due to human activity.

The main greenhouse gases are: carbon dioxide (CO2), methane, nitrous oxide (N2O), chlorofluorocarbons (CFCs); also water vapour (H2O) is producing the greenhouse effect.

Carbon dioxide

The concentration of the most important greenhouse gas, carbon dioxide, has increased in the atmosphere from 290 ppmv (parts per millions by volume) in 1880 to about 380 ppmv in 2006, and is going to increase in the next future, because carbon dioxide, with water, is the final product of the combustion of fossil fuels (oil and derivatives, methane and hydrocarbons, coal), and of living and dead vegetation (biomass burning). The fossil fuels can be considered reservoirs of carbon, made ages ago; their combustion lets carbon return (as dioxide) into the atmosphere, increasing the greenhouse effect. Carbon dioxide is easily soluble in water: the oceans contain enormous amounts of it, but the temperature increase (due to the greenhouse effect) reduces its water solubility, releasing new gas into the atmosphere, and accelerating the greenhouse effect.

What will be the main consequences of greenhouse effect?
There is no dispute about the human responsibility on the greenhouse effect, but much is still debated on its possible consequences.

The most authoritative studies have been carried out on behalf of UN by IPCC (Intergovernmental Panel on Climate Change); according to a report by this Committee, underwritten by hundred  of scientists (IPCC WGI Third Assessment Report – SPM, issued in January 2001) , the Earth is really warming :

  • The global average surface temperature has increased over the 20th century by about 0.6 °C. Globally, it is very likely that the 1990s was the warmest decade and 1998 the warmest year in the instrumental record, since 1861.
  • According to British scientists, 2005 has been the warmest year in the Northern Hemisphere, and the second warmest globally since 1861.
  • Satellite data show decreases of about 10% in the extent of snow cover since the late 1960s. In particular equatorial snows and glaciers are disappearing quickly, on the Peruvian Ands and in Africa (33% of Kilimanjaro ices have melted over the past 20 years); the thickness of Arctic sea-ice in late summer is decreased.
  • Warming of the whole Antarctica has not been demonstrated; but in West Antarctica, especially in the Antarctica Peninsula (southern of the Latin America), massive landslides of enormous icy areas forming icebergs are observed. It is not clear if this process is related to the greenhouse effect or if it is the result of regional climatic changes.

Global average sea level has risen, mainly due to the thermal expansion of seas ( ice retreat is not the main reason): the increase over the 20th century has been between 10 and 20 centimeters.

Global Climatic Trend: Projections until 2100

The projections of the IPCC, carried out with greatly improved methods compared to the past, indicate big increase in atmospheric CO2 concentration due to human activity, with significant climatic consequences:

  • The globally averaged surface temperature is projected to increase by 1.4 to 5.8°C over the period 1990-2100: the rate of warming, too, should increase compared to last century.
  • Warming should be most notable in some areas of our planet (northern regions of North America, northern and central Asia).
  • Heat waves, droughts, drier soils.
  • Increased evaporation and precipitation due to higher energy in the atmosphere: more frequent and extreme weather events (storms, tornados, hurricanes).
  • Sea levels will go on rising: erosion of sandy beaches or flooding of coastal areas (e.g., Bangladesh, Nile Delta) and small islands (specially the atolls in South Pacific).
  • Easier transmission of some infectious diseases, including malaria and yellow fever.


How long will Climate Change?

The emissions of the most persistent greenhouse gases (carbon dioxide, nitrogen protoxide, per fluorocarbons) have a lasting effect on the climate: e.g., about a quarter of carbon dioxide persists in the atmosphere several centuries after the emission.

Even if greenhouse gases concentration could be stabilized, the average surface temperatures and sea level would go on rising for centuries, due to the fact that deep Oceans follow climatic variations with big delay.


Actions against greenhouse effect
The following actions have been suggested to reduce greenhouse gas effect:

  • Energy saving; using energy renewable sources (sun, wind, hydropower, geothermal, biomasses) or, among fossil fuels, prefers natural gases to oil or coal (light hydrocarbons combustion is producing less carbon dioxide).
  • Gradual elimination of CFCs , see our page about Ozone Depletion .
  • Planting new forests, saving the old ones.


Kyoto Protocol

Kyoto Protocol is an international agreement, underwritten in 1997 from 84 countries, committing developed countries to reducing their overall emissions of greenhouse gases. The Protocol was finally ratified by 146 countries and came into effect in January 2005.

An average 5% cut of greenhouse gases emissions has been fixed within 2012, compared to 1990 emissions level.  Each country took on a different percentage target within this overall target.

An average 5% cut would be a great result (many countries should reduce their emissions instead of increasing them sharply), but unfortunately not enough to stop the temperature increase; for this reason the term “climate change mitigation” is often used. 

3. Acid Rain
Problem

  • Water creatures are affected.
  • Food chains are exaggerated.
  • Fertility of soil is affected.
  • Skin cancer.

Solution

  • Mixed Ca (OH) ² in the water to prevent the reaction of acid.
  • Prevent air pollution.


4. Global Worming

Like the glass panes in a green house, certain gases in the earth’s atmosphere permit the sun’s radiation to heat the earth but retard the escape into space of the infrared energy radiated back out by the earth. This process is referred to as the green house effect. These gases, primarily carbon dioxide, methane, nitrous oxide and water vapor, insulate the earth’s surface, helping to maintain warm temperatures. Without these gases, the earth would be a frozen planet with an average temperature of about -18°C instead of a comfortable 15°C. if the concentration of these gases were higher, more heat would be trapped within the atmosphere and world wide temperature would rise.

Within the last century, the amount of carbon dioxide in the atmosphere has increased dramatically, largely because of the practice of burning fossil fuels- coal and petroleum and its derivatives. Global temperature has also increased 1°C within the past century. Atmospheric scientists have now concluded that at least half of that increase can be attributed to human activity and they have predicted that unless dramatic action is taken, temperature will continue to rise by between 1°C and 3.5°C over the next century. Although this may not seem like a great difference, global temperature was only 2.2°C cooler during the last ice age than it is presently. The consequences of such a modest increase in temperature may well be devastating. Sea levels will rise, completely inundating a number of low-lying island nations and flooding many coastal cities such as New York and Miami. Many plant and animal species will probably be driven into extinction, agricultural regions will be disrupted and the frequency of severe hurricanes and droughts in likely to increase.

Author: Material Developer, BRAC Education Programme, BRAC, Dhaka, Bangladesh.

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