a grab, Foremost 17 had what Johnstone called the "iron man". This was described as having robotic arms and legs that could walk on the sea bed at depth, picking up heavy objects. It was operated directly from the diving chamber, instead of relying on an observer relaying instructions to an operator on the surface. Foremost 17 found Niagara on 16 April 1953. By 23 July she had recovered 30 of the 35 remaining gold bars and Johnstone had ended the salvage operation. Five bars remain unaccounted for. The wreck since 1953 A New Zealand law passed in 1979 protects an underwater communications cable that passes near the wreck. This law forbids any vessel anchoring above the wreck without special permission. In 1988 marine salvage specialist Keith Gordon from Albany, New Zealand explored the wreck with a remotely operated underwater vehicle. The wreck has become an artificial reef, rich with marine life. Since 1999 scuba divers have visited and explored it. Where the strong room used to be is now a crater littered with débris. Gordon recovered Niagaras bell in 2007. Environment Niagaras fuel oil capacity was 5,000 tons. Maritime New Zealand says it does not know how much oil remains in the wreck. News reports from the 2010s variously estimate the amount at 1,000 tonnes, 1,500 tonnes, or 4,200 tons (sic). Oil has escaped from her wreck ever since she was sunk in 1940. In the 1980s Keith Gordon saw oil escaping from the wreck and forming a slick long. Another escape was photographed in 2000, when marine environmentalist Wade Doak described the wreck as a "ticking timebomb", threatening Whangārei's mangrove systems and the Hen and Chickens Islands nature reserve. In 2015 she was described as "still bleeding oil". Maritime NZ says that the remaining oil is in a semi-solid state because of the pressure and low temperature at that depth. But the wreck is deteriorating, and climate change is increasing the sea temperature. A new contingency plan was made in 2016 in case a large amount of oil suddenly escapes. Environmentalists including Doak, salvage experts, and Auckland politician Mike Lee have called for the oil to be extracted from the wreck to prevent such a disaster. In 2017 Gordon estimated that with modern technology, the oil could be extracted at a cost of about NZ$6 million. In 2018 an art exhibition was held in Mangawhai Heads to raise