Japan on Monday marks the second anniversary of its worst peace time disaster, when an earthquake-tsunami struck, triggering the Fukushima nuclear catastrophe.

Below are some commonly asked questions regarding where Japan stands two years since the multiple crises.

Q: What happened on March 11, 2011?

A: A 9.0-magnitude offshore earthquake struck under Pacific waters off Miyagi prefecture in northern Japan at 2:46 pm (0546 GMT). It set off a gigantic tsunami up to 20 metres (65.5 feet) high that swept much of the northeastern Pacific coastline.

Q: What was the human damage done by the disasters?

A: Japanese police say 15,880 people died as a direct result of the natural disasters, while 2,694 others remained unaccounted for as of late February. In addition, 2,303 survivors of the quake/tsunami died in complications associated with stress and difficulty of living after the disasters.

The natural disasters destroyed or damaged more than a million homes, mainly in the northern Tohoku region.

The earthquake and tsunami also triggered the Fukushima nuclear crisis, the worst atomic accident in a generation, although it not officially recorded as having killed anyone.

During the first days of the triple disasters, some 470,000 people fled from their homes.

Two years on, 315,196 people are still without permanent homes, mainly living in temporary housing units or staying with relatives.

Q: What happened at the Fukushima Daiichi power plant?

A: The worst nuclear accident since Chernobyl in 1986. The tsunami knocked out emergency power supplies being used to cool reactors. Overheating reactors went into meltdown. Buildings housing the reactors exploded because of massive hydrogen build-up, releasing radioactive materials into the environment. The power plant's operator Tokyo Electric Power (TEPCO) refused for two months to admit any meltdown had taken place.

Q: Has anyone been held accountable for the nuclear accident?

A: No one has been criminally charged for the disaster. Activist shareholders of TEPCO have sued the utility's executives for causing damage to the company by promoting nuclear programmes. Many Fukushima families were planning to sue the government.

Q: Is the Fukushima crisis over?

A: No. In December 2011, the government declared that the plant was in a state of "cold shutdown," where it is no longer releasing dangerous levels of radioactive materials. But scientists warn that many families from areas near the plant will never be able to go home.

On the vast campus of the damaged Fukushima plant, TEPCO has built a temporary system to keep the volatile and damaged reactors cool.

Officials are still mulling how exactly to clear debris and to remove nuclear fuel from the reactors.

The government and TEPCO plan to spend up to four decades decommissioning the units.

Q: How much debris did the tsunami leave behind, and has it been all cleared?

A: The government estimates the hardest hit Iwate, Miyagi and Fukushima prefectures were left with a combined 26.7 million tons of debris, including broken buildings and sand and other debris brought ashore. Only a third of it has been incinerated or properly disposed of, while the rest either is still piled at temporary collection sites or left untouched.

Q: What is the cost of rebuilding Japan?

A: The government originally planned to spend 19 trillion yen ($200 billion) for five years to rebuild the disaster-hit region. Prime Minister Shinzo Abe, who came to power in December, has suggested expanding the spending plan.

Q: What was the cost of the Fukushima crisis?

A: TEPCO, which has come under state control since the disaster, has estimated it will have to pay at least 3.24 trillion yen to compensate those who had to flee their homes, or abandon businesses, farmland and fishing grounds.

The government and TEPCO also face enormous costs for the clean-up of radioactive materials and dismantling the reactors.

Q: Is Japan safe to visit? Is Japanese food and water safe to consume?

A: Most areas in Japan are safe, except for the highly contaminated areas immediately surrounding the Fukushima Daiichi plant. Japanese farm products available in market places are safe for human consumption, although many consumers have avoided food items grown or caught in or near Fukushima.

The government has banned distribution of fish and produce from areas surrounding the nuclear plant.

Q: Have Japanese people decided to give up nuclear power?

A: No. Opinion polls have shown the majority of adults wish not to continue with Japan's nuclear programme. But in the December lower house election, the conservative Liberal Democratic Party, which stood firmly behind nuclear power, enjoyed a landslide victory for its pledges to boost the troubled economy. The business sector has loudly pushed for continued use of nuclear power.

But Japan has set a high hurdles for resumption of nuclear reactors. Only two of Japan's 50 reactors are in operation with strong public opposition preventing reactor restarts. Japan's new nuclear regulator has imposed very strict conditions before utilities can restart nuclear reactors.