(a) What were the main objectives of Clean Development Mechanism? Also explain the reasons for the criticism on Kyoto Protocol by the developed countries. (b) Differentiate between Sanitary and Industrial Landfills, also describe the land selection criteria for Landfills.

(a) Clean Development Mechanism

The Clean Development Mechanism (CDM) was created under Article 12 of the Kyoto Protocol, adopted in 1997 and in force from 2005. It let industrialised (Annex I) countries fund emission-reduction projects in developing countries and earn Certified Emission Reductions (CERs), each equal to one tonne of CO₂ equivalent, which they could count towards their own targets.

Main objectives

(i) to help developing countries achieve sustainable development; (ii) to help Annex I countries meet their binding emission targets; (iii) to reduce emissions where doing so costs least, since a tonne of CO₂ has the same climate effect wherever it is avoided; (iv) to move finance and clean technology to developing countries; (v) to involve the private sector and developing countries in climate action, and so serve the Convention's ultimate aim of stabilising greenhouse gas concentrations.

Criticism of the Kyoto Protocol by developed countries

The Protocol set binding targets only for developed countries, averaging about 5.2 percent below 1990 levels for 2008-2012. Their objections were as follows.

Exemption of major emitters: large developing economies such as China and India had no binding targets. The United States Senate's Byrd-Hagel Resolution (1997) opposed any treaty that excluded them, and the US never ratified the Protocol.

Economic cost: critics argued that the cuts would raise energy prices, slow growth and reduce employment. Carbon leakage: industry could move to countries with no limits, so global emissions might not fall at all.

Limited effect: because the largest and fastest-growing emitters were outside its limits, the Protocol covered a shrinking share of global emissions. Canada withdrew in 2011, while Japan, Russia and New Zealand declined targets in the second period. Weak market results: developed country critics also questioned whether CDM projects were truly additional, meaning whether they would have happened anyway, and pointed to low carbon prices and uneven enforcement.

(b) Sanitary and industrial landfills

A sanitary landfill is an engineered site for municipal solid waste, in which waste is spread, compacted and covered with soil daily. An industrial landfill receives non-municipal waste from factories and power plants, such as ash, sludge and construction debris. Hazardous waste needs a separate, more strictly controlled secure landfill.

Waste received: sanitary landfills take mixed household and commercial waste, while industrial landfills take process waste, often of one or a few types. Main concern: sanitary sites produce landfill gas (methane and CO₂) and organic leachate from decomposition. Industrial sites are more often concerned with metals, salts and chemicals in leachate, and may produce little gas. Design: a sanitary landfill uses a liner, a leachate collection system, gas collection and daily cover. An industrial landfill's design depends on the chemistry and leaching behaviour of the waste, so requirements vary. Monitoring: both need groundwater monitoring. Industrial sites also need waste testing and control over what may be accepted.

Land selection criteria

Geology and soil: low-permeability soil such as clay, and stable ground away from active faults. Water protection: a deep water table, and a safe distance from rivers, wells, wetlands and flood plains. Distance: away from homes, schools and airports, since birds attracted to waste endanger aircraft, yet near enough to keep transport costs reasonable. Capacity: enough land for 20 years or more of use, plus buffer zones. Access: all-weather roads and an available source of cover soil. Climate: rainfall affects leachate volume and wind direction affects odour. Social and legal factors: land cost, zoning, public acceptance and protection of ecologically or culturally sensitive sites.