The Samudrayaan Mission & the Marine Ecosystem

 

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The Samudrayaan Mission heralds India joining the race for mining the seabed for  minerals, metals and ores. The submersible vehicle ‘MATSYA 6000’ is being fabricated at the National Institute of Ocean Technology in Chennai. While it is certainly a technological step-up from the Chandrayaan Mission, we need to understand the positives and negatives of seabed mining.

Let us first understand what are these submersible vehicles, also known as submersibles and their role in deep-sea mining. As we all know, there are five oceans on this planet: Atlantic, Pacific, Indian, Arctic, and Antarctic. The Pacific Ocean is the largest and deepest ocean. The average depth of the ocean is about 12,100 feet. The deepest part of the ocean is about 35876 feet. The Indian Ocean's average depth is 12,274 feet, and its deepest point is 24,442 feet. Obviously, all oceans are so deep and their submerged topography is so varied that special instruments, vessels and vehicles will be needed to explore and mine their mineral wealth. Thus, underwater robots have been designed to visualise, sample, and survey deep-sea environments, and collect information from the oceanic depths, which is then analysed for various purposes. These submersibles are capable of withstanding immense pressures while working in extreme cold and darkness. There are three types of submersibles: HOVs or Human Occupied Vehicles, ROVs or Remotely Operated Vehicles, and AUVs or Autonomous Underwater Vehicles. 

HOVs accommodate four or five persons. They take these persons - mostly scientists - to the oceanic depths for collecting data and samples with the help of cameras, sensors, manipulator arms etc. 

ROVs are tethered to a ship. The personnel manning the ship control the ROV’s functions for collecting specific data and related information. A manipulator arm is used to collect samples from the ocean’s floor. All data and samples are then analysed in laboratories to learn about the ocean’s ecosystem and the nature of minerals etc found there.

AUVs are independent underwater robots which are deployed for exploring the oceans. These are not tethered from a ship, nor controlled by onboard operators. These are used for completing pre-planned missions without direct control from operators. AUVs have made deep-sea mapping very easy and accurate. These vehicles also collect high-resolution data, which are collected by researchers once the AUVs have surfaced. These  are also extremely useful for military surveillance.

In the Indian context, the Matsya 6000 vehicle for the Samudrayaan mission is an HOV. Its success will place India at par with the countries like the US, Russia, Japan, France, and China.

So, why has it become necessary to explore the oceans? Well, the demand for metals and minerals for meeting the requirements of the ever-growing technology and electronics industries is experiencing an exponential boom. Cell phones, wind turbines, and electric cars require large quantities of rare and expensive metals.

As the exploitation of onshore sources of important minerals, ores and metals is nearing saturation limits, exploring the offshore sources has become imperative. Various international explorations have discovered the existence of rich deposits of manganese, nickel, copper, and cobalt in deep ocean basins. It has been revealed that the crusts that are rich in iron and manganese also possess significant concentrations of cobalt, rare earth elements, nickel, tellurium, and platinum. The rare earth elements are widely used in smart phones, wind turbines and hybrid and electric cars. Phosphorites, which occur in the ocean as crusts or nodules, are a critical source of phosphate for fertilisers and are also being evaluated as a potential source for rare earth elements.

India depends heavily on imports of rare earths and other strategically important minerals and metals. For example, around 90% of its rare earth metal requirements are imported from China. Since these metals are of great strategic value - as these are vital inputs for hi-tech defence related equipment and systems - such heavy dependence on a hostile country is fraught with high risk to the national security. Although these rare earths have become available within India as also in Australia and the United States, their demand is increasing phenomenally. So, Samudrayaan’s success becomes all the more imperative. This mission is going to explore the possibilities related to mining precious metals and minerals, notably cobalt, nickel, and manganese. 

Initiated more than two years ago, Samudrayaan is estimated to cost around Rs. 4000 crores by the time it is completed in 2026. However, there are certain wrinkles in the project that need to be addressed. For instance, the vehicle, Matsya 6000, resembles the Titan submersible, which met with a tragic end on June 18 2023. The Titan submersible was owned by OceanGate Expeditions, an American Company, which took tourists to the underwater site of the Titanic luxury liner’s wreckage. As is well known, on April 15, 1912, the British ocean luxury liner Titanic sank into the North Atlantic Ocean about 400 miles south of Newfoundland, Canada. The massive ship had 2,200 passengers and crew onboard, when it struck an iceberg and sank.

Coming back to the 2023 tragedy, on that fateful day, there were five passengers aboard, including the OceanGate CEO Stockton Rush and the British billionaire Hamish Harding. The submersible Titan lost contact with its surface vessel Polar Prince after it dived into the ocean. It had about 96 hours of oxygen, but it was not enough to sustain the victims until the rescuers arrived. Clearly the submersible could not withstand the pressures of the deep sea and imploded.

Samudrayaan Mission’s scientists must have factored in the above information and also other possible risks. The Matsya-6000 submersible vehicle can withstand the deep-sea pressures for 12 hours, and is equipped to survive for 96 hours in case of an unforeseen mishap.

Even as the hunger for ores and minerals pushes countries towards exploiting the marine wealth there are deep concerns regarding the impact on environment. Let us examine these concerns:

1. Polymetallic nodules support complex ecosystems in the oceans. If the nodules are removed, several species will be wiped out forever. One single mining project can destroy around 9000 square kilometres of seabed in three decades. And we all know that mining operations can last for several decades.
2. Deep sea sponge and coral ecosystems - some of which have formed over thousands of years - will be destroyed. 
3.  Since mining will inevitably stir up the ocean floor, sediments will spread over vast areas, adversely affecting the existence of corals and sea sponges that are filter feeders. As you know, in order obtain food, sponges pass water through their bodies in a process known as filter-feeding. Water is drawn into the sponge through tiny holes called incurrent pores. The sediments will block these pores and smother them to death.
4. Finally, the mining operations will create different forms of pollution, There will be spills from the fuel and other chemicals. Noise, vibration and light will add to the misery of the surviving species.

No matter what assurances are given, deep sea mining will have the same adverse effects on the marine ecosystems as on-land mining operations have had on our environment. 

The march of civilisation demands a heavy price indeed.