The wreckage has been moved to a frontier post and the work to collect the snow and ice that was contaminated with fuel has also been completed.
The Ministry of Natural Resources is analyzing the lake's water after the clean up work was completed. If they detect the presence of kerosene, then the crash site was insufficiently cleaned.
The ministry recommended that the military collect the contaminated snow and the upper layer of ice (in an 3,600 square meter area), absorb the liquid, pour out the purified water outside the area of the lake and bring the sediment to Petropavlovsk.
The Bolshoi Kalygir Lake is a traditional spawning ground for valuable species of salmon: humpback salmon, red salmon and king salmon.
The contaminated water could seep into Maloye Lake and then the Pacific Ocean, the route the fish use to go to their spawning grounds.
The Air Force's Mi-8 helicopter made an emergency landing on the ice-covered Kalygir Lake on January 22. The helicopter's fuselage and fuel tanks were seriously damaged.
Three crewmembers and two passengers waited for aid in hunter's huts, 2.5 kilometers away from the crash site. They received serious injuries during the emergency landing.
The prosecutor's office is investigating the criminal case under the article, "Violation of the Use of Flying Vehicles and Flight Safety Rules."