Niburu was not the planet whose atmosphere needed repair. Niburu was the planet-sized craft the Anunnaki used to travel the heavens in search of gold.
Also,the Anunnaki did not come to Earth to specifically make humans to mine their gold. At first, they used machine craft to dredge through ocean water here on Earth,but the process was taking too long and not yielding satisfactory amounts of gold. Then they decided tomine it from the Earth. They used the lower ranking crew members to do this manual labor. The Anunnaki society had not done any work like this in thousands of years and their bodies weren't built to take the hard labor of mining. The lower ranking Anunnaki rebeled. One of the Anunnaki remembered an old and almost forgotten technology. The idea was given to Enki and he consulted the medical officer Ninti to take Annunaki blood and use that DNA and graft it onto a hominid species native to Earth to accelerate its evolution to a smarter more capable being that could do the work for them. This creation became homo sapiens.
Enlil was brother to Enki and on this mission. Enki (ruler in ki, 'ki'/'qi' is earth) was in charge of the gold harvesting tasks on the planet. Enlil (ruler in lil, 'lil' means skies) was incharge of the orbiting craft in space. Enlil did not approve of Enqi's decision to make the humans. In the To'rah, is the force or G-d that helps humanity and Enlil is the G-d that tries to restricy human evolution and accumulation of knowledge. At one point, Enki is the serpent in the garden introducing the Adamite people to a sexual tantric technique to open their third eye so that they can learn things for themselves much faster without the Annunaki. The verse that says 'Now man has become as us TO KNOW the good from the evil" states how 'to know' things how the sole province of the Anunnaki and not man,unless it was given to the man by the Anunnaki. So they cut off man from the Tree of Life which is most likely a euphimism for the higher brain functions that would enable telepathy, clairvoyance, prescience and the like. This was the decision of Enlil and not Enqi. Enlil wanted to destroy humanity because he thought our existence was unethical in the greater scheme of things. In the great flood to destroy the giants (fallen Watchers and Nephilim) man was also slated for destruction too.It was Enqi who warned Noah, as Noah was one of his descendants. Noah still had retained the higher brain faculty of prophecy.
Nimrod was a mighty seeker (of knowledge) and was an affront to Enlil. Thats how the translation should have gone. The word for 'mighty' which was 'gibor' is the same word used in Genesis 6:4 describing the Nephilim as the mighty men (or some translations say 'heroes' instead of mighty men). Nimrod was of the 'giborim' and he sought to use the ley line structure of the planet. He built megastructures across the globe on the 30th (or 33rd or 34th, I forget) parallel to capture this energy. The Tower of Babel in Genesis 11 is his doing. Apparently he was able to reactivate the telepathic omponent of higher brain functioning so that this was the one language everyone understood and communicated with. Nimrod was building a ziggurat array (think of Joseph Farrell's Giza Death Star Great Pyramid meets HAARP). Enlil and his retinue in orbit around the Earth would have none of this so they came down to the planet's surface and did whatever they did to make the telepathic function that Nimrod had reactivated defunct.
The Bible has more than one G-d in it. It is the English mis-translation and ignorance of the Babylonian influences the Hebrews practiced and recognized. The To'rah was written while in Babylonian captivity. And as has been found out, hostages or captives begin to take on the beliefs of their captors and start to sympathize with them (this is known as Stockholm Syndrome). The Hebrews were no different. The Hebrews come from Abraham and Abraham was right out of Ur of Chaldea.The sacrifices mentioned through out the Old Testament involving fire and flesh and blood come right out of Chaldea. Anyone can easily research the matter on how the Chaldeans or Babylonians sacrificed humans and animals and see it in the Torah. The part in the Torah where it says having one's sons or daughters pass through the fire is the child sacrifice. This was to deities like Molech and Baal. When one of these deities visits Abraham in Genesis 18 he is afraid for his life so he has everyone scurry to hastily get them some flesh to eat. In the King James Version it says the calf gotten was only dressed it didnt say cooked. So here G-d is sitting and consuming raw flesh. Probably not Enlil/Enki, but was one of the nephilim from Genesis 6:1-4.The Book of Enoch goes into detail how these nephilim or giants ate everything in sight, animals and people. The 200 Fallen alo brought knowledge of various kinds which the forces of Enlil (which is the conservative voice of church doctrine) says this knowledge is evil and wicked.