There are already millions of Biharis in Tamil Nadu . To be fair , they are a hardworking lot and a good people . As for Hindi imposition , Tamil is a language native to india and has a literary repertoire far greater than that of young Hindi , so any attempt at Imposition of Hindi by smug delhiwalas will be kicked on the back so hard that it won't know what hit it .( Not only Tamils,Kannadigas and Telugu and Malayalis are also proud of their language , in fact Kannadigas are more crazy about their language than even the Tamils) Tamils are proud Indians and they speak one of the two oldest mature languages native to India (Tamil and Sanskrit)
Tamil Nadu has traditionally welcomed to all migrants . They are always welcome to contribute to the society of Tamil Nadu and make a living for themselves in the process. Gujjus, Marwaris,Telugus ,Kannadigas, Marathis, Malayalis and Hindi folk have been living here peacefully for several generations now , some families even for 100+ Years ,and are proud Tamils by naturalisation ....Recently the Bengalis , Oriyas , Nepalis , north easterners and Biharis have also been coming in in droves for livelihood.
If there's anything Bihar can learn from Tamil Nadu , it is how to bounce back from from being an absolute bottom ranked state in all indices ( Tamil Nadu was at the bottom of all large state rankings in the early 1970'sto the early 1980s) to become a major part of India's success story .