Degradation of the ozone layer

Production of CFCs is being phased out because they damage the earth’s stratospheric ozone layer, which prevents much of the sun’s ultraviolet light from reaching the earth. Degradation of this layer can cause an increase in skin cancer and a reduction of crop yields. As CFCs escape from junked or faulty compressors and hoses, or when used as solvents, they rise to the stratosphere. There they are transformed by ultraviolet radiation into chlorine atoms, which play a role in catalytic ozone depletion.

Scientists estimate that since the late 1950s, the ozone layer over Europe and North America has decreased by 10%. And the United Nations World Meteorological Organization announced that the largest hole ever measured in the earth’s ozone layer – a 3.86 million square mile gap – existed over Antarctica. As negative ozone figures kept coming in, developed countries agreed to eliminate the production of CFCs, except for a few essential uses. The “essential” exceptions allow for the production of CFCs for use as propellants in aerosol sprays for use by asthmatics, and for the use of small quantities in laboratories.

To accelerate tje switch to new equipment that can use alternative refrigerants, the United States levied a hefty, annually graduated excise tax on all new and imported CFCs, beginning in 1990.

CFCs are mélange of chemicals compounds. Their designations were developed by DuPont in the 1930s as an esoteric code intended to keep competitors from knowing the product’s chemical makeup. That code has long since been revealed and is used by the entire industry. The most widely used compound is CFCs-12, also known as R-12, which carries the DuPont trade name Freon. Its primary use is a refrigerant in residential refrigerators and mobile air conditioners. The automotive industry used about half the worldwide production of CFCs-12, or some 125 million pounds per year. Other CFCs, such as 12,113, 114 and 115, are used in the production of foam rubber and rigid insulating foam for appliances and construction, and as solvents, especially in the electronics industry. All of these CFCs are being replaced with an equally number of hydrofluorocarbons or hydrochlorofluorocarbons, known as HFCs and HCFCs, respectively.

Yet these replacements for CFCs are no panacea. It is known, for example, that HCFCs can also deplete the earth’s ozone layer at a considerably slower rate than do CFCs. To address this problem, the 1992 meeting in Copenhagen also adopted a complex phaseout schedule for HCFCs. The agreement calls for the reduction of HCFCs in five stages beginning in 2004, with a total phaseout by 2030. And, although HCFCs have not been associated with ozone depletion, both they and HCFCs have recently been cited as possible acid rain culprits.

 

2.Oil and Fish(1)

The Far Eastern and North Pacific shelves, with their severe climatic conditions present the great risk of contingencies with the worst of imaginable consequences. We should pay our attention to the latent anomalies existing in the region. For instance, in the locations of prospecting drills, changes in the marine ecosystem were observed resulting from mineral mixture released in the sea water. Another group of adverse factors: alienation of fishing areas, laying of pipelines without flushing with the sea bottom, covering of the sealed wells openings with special armature (4.5 m high, 3-4 sq. m), dumping of drilling platform debris, anchors, wires, tractors, etc. on sea bottom.

This given concept considers allocation of protected zones where oil prospecting and drilling will be prohibited under all conditions, as well as zones requiring additional environmental studies and limitations to avoid negative consequences. For the purposes of legal support, it will be necessary to alter the existing decision-making procedures for oil and gas prospecting on the marine shelf, which no longer comply with the environmental protection requirements.

At the same time, we should not exaggerate the risks of oil and gas prospecting projects. Thus, for instance. according to American scientists, oil drilling does not present too much danger. Risk of pollution resulting from an oil spill at а drilling site is а mere 2%, while that resulting from transportation reaches 50%.

Sea water dissolves about 5% of oil products, or even more. Released in sea water, the oil undergoes physical, chemical and biochemical changes. The volatile components, making from 20% to 50% of the crude oil, evaporate very intensively at the very beginning, than less so throughout the whole period of their presence in the sea water. Generally, the crude oil releases about 50% of its components into the atmosphere. Due to the evaporation. Very active is self-removal of the light gasoline and kerosene fractions, diesel fuel and other low-molecular compounds. However, this cannot be considered as self- purification of the sea environment, as it was thought sometimes.

 

Oil and Fish (2)

The Sea of Okhotsk is exclusively productive in terms of marine resources, which is а very important factor for local fishing industry. Any oil and gas extraction projects, with concurrent transportation and construction developments will have an irrevocable negative consequences, unless necessary preventive measures are taken to protect the environment. Any oil and gas prospecting schedules should evaluate, in the first place, the possible impact on the ecosystems of the shelf.

Any such projects will undoubtedly take effect on the environment, this way or the other. Therefore our objective will be to evaluate not only the potential pluses of the projects, but the negative consequences. The gist of the problem is that potential oil and gas bearing areas coincide with the areas of active fisheries and habitats of the most valuable fish species and endangered sea mammals. Therefore, on the initial stage it would make the best sense to pinpoint the areas where such projects would be prohibited under all conditions (е.g.: natural reserves); areas, where the works would be permitted if only certain conditions were met (е.g.: seasonal works); and finally, the areas where the works would be possible without limitations.

During seismic surveys, explosions (drastic changes of pressure) create conditions for lethal impact on hydrobionts, especially on the early stages of their development. During drilling works, each stationary oil-rig on the shelf becomes а source of multi-component and continuous pollution, including: drilling solutions. ground waters, hard particles, drilling wastes with high content of oil products, barite. lubricants, heavy metals, radionuclides, emulsifiers, biocides, and other toxins. Average daily waste output of one stationary oil-rig off Sakhalin East Coast, based on materials of an oil field development project, may approximate 60,000 cubic meters of drilling solution, 15,000 cubic meters of hard particles, and 640 cubic meters of ground waters spreading for 3 to 12 kilometers around the drilling site.

How weeds clean water

Fanciers of tropical-fish use marine vegetation to help keep the water in their aquariums clean and the same or similar plants are used in many reservoirs to aid the process of water purification. Now engineers are using the same approach to help purify sewage and industrial water wastes.

The "living-filters", which include a number of reeds, rushes and irises cleanse water in a variety of interrelated ways. They absorb inorganic pollutants such as nitrates, phosphates and metals and toxic organic compounds such as phenol. Their roots trap small particles of insoluble pollutants. The plants reduce the-number of' pathogenic bacteria in water, possibly by producing chemicals that destroy the bugs. They add oxygen to dirty water and act as hosts for-various bacteria, insects and small fish that also clean up pollutants.

Sudanese tribesmen have long used green plants to I make the murky waters of the Blue Nile potable and I palatable, but the large-scale use of this natural treatment is a recent innovation. The most advanced-process of this kind is a system used to purify water from the befouled Rhine River for the German town ofKrefeld. The Rhine water, containing huge amounts.of municipal and industrial sewage, is first subjected to chemical treatment which removes the bulk of the pollutants, and then sprayed into a lagoon planted with bulrushes. The spraying increases the amount of oxygen in the water, and the rushes remove almost all of the remaining pollutants, including toxic organic chemicals and coliform bacteria. This water infiltrates the soil below the lagoon —^: which purifies it further —- and is then pumped off, through wells dug close to the lagoon into Krefeld’s water system.

Other schemes using green plants are on a somewhat smaller scale. In Holland’s Zuider Zee region, long waterfilled trenches planted with reeds have success-fully cleaned up sewage from summer camp sites, at about a quarter of the cost of conventional plants. Researchers are testing the use of natural and artificial marches to treat municipal effluents and experimenting with lagoons full of water hyacinths for the same purpose.

Experts recognize that the method is not a panacea f or water-treatment problems. The plants require a lot of space, are vulnerable to pollutants that kill plants and cannot work year-round in areas where ponds freeze. Nevertheless green plants could provide-clean water for small communities that cannot afford full-scale purification systems. And in combination with conventional techniques, biological treatment offers relatively cheap way to remove the last traces of the pollutants that now end up in the drinking water of most large cities.