Can I be fired for being hearing impaired?

I have severe hearing loss. 85% of my hearing is gone. I had meningitis when i was 2 yrs old which resulted in my loss of hearing. I am 28, so i have been wearing hearing aids for 26 years. All my life i tried to act as if i did not have a disability. I tried to function as best as i could although i believe my life would be drastically different if i would have been able to hear normal. My hearing as made it hard for me at time to reach my potential in school and at work. Recently i quit a good job to accept a job at a class one railroad. I talked to the railroad hiring manager at my initial interview about my condition and ultimately i was offered the job and passed a pre employment health screening which included a hearing test. I was offered the job. I worked there for 3 months, then i was put on suspension because i had a hard time understanding the work radio. I have been on suspension for over a month. I requested special accommodation to allow me to hear better, which is why they put me on unpaid suspension so they could order something for me. Im not sure its even right to put me on unpaid suspension since i provided all my medical evidence to them before being hired for the job. I have a strong feeling that ultimately i will be fired from this job because of my hearing issues. Hopefully that will not be the case. Does my employer have the right to fire me because of my hearing condition. Should they at least try and find me some other work to do within their company that doesn't require me to hear over a work radio?