Oil Spills in Seawater

GS3 – Environment

Context:

A Liberian cargo ship sank off Kerala carrying diesel and calcium carbide, posing a risk of oil spill and chemical reaction with seawater.

Oil Spills:

• Unintended release of petroleum hydrocarbons into marine/coastal waters.
• Major causes:
  → Ship accidents
  → Offshore drilling mishaps
  → Pipeline ruptures
  → Storage failures

Environmental & Human Impact

• Highly toxic & long-lasting pollutant
• Damages coral reefs, mangroves, and marine ecosystems
• Kills marine animals → disrupts food chains
• Affects fisherfolk, tourism, seafood safety
• Global toll: ~60,000 deaths annually, especially among children and coastal communities

India-Specific Concerns

• High-risk coastline due to dense maritime traffic, oil rigs, and refineries.
• Sensitive ecosystems like Sundarbans mangroves, Gulf of Mannar reefs are vulnerable.

Oil Spill Cleanup Methods

Method	Description
Bioremediation	Uses oil-eating microbes (e.g., Cycloclasticus, Oleispira); eco-friendly
Containment Booms	Floating barriers to contain spread
Skimmers	Mechanical tools to remove surface oil
Sorbents	Absorb/adsorb oil using natural/synthetic materials (e.g., straw, ash)
Dispersants	Chemicals to break oil into droplets; faster decay but may harm marine life
In-situ Burning	Controlled burning of oil slicks; fast but emits toxic smoke

Legal & Institutional Framework

International Conventions

• MARPOL 73/78 (Annex I): Prevents oil discharge from ships; India is a signatory.
• Bunker Oil Pollution Convention (2001): Compensation for bunker fuel pollution; ratified by India in 2015.
• Civil Liability Convention (CLC, 1969) & IOPC Fund (1992):
  → Makes shipowners liable for oil damage
  → Provides additional compensation if owner’s liability is exceeded

India’s Domestic Mechanisms

• Merchant Shipping Act (1958): Adopts MARPOL norms.
• National Oil Spill Disaster Contingency Plan (NOS-DCP), 1993:
  → Led by Indian Coast Guard
  → Ensures rapid, coordinated response
• National Green Tribunal (NGT) Act, 2010:
  → Handles environmental litigation
  → Awards compensation for ecological and community loss

Additional Insight: Marine Emissions

• Shipping emits ~1 billion tonnes of CO₂/year
• If shipping were a country → 6th largest polluter globally
• Bunker fuel is 100x dirtier than diesel
• Cruise lines (e.g., Carnival) emit more SO₂ than Europe’s 260 million cars combined