SNR=0 in FFT Plot

So I have this signal that I transformed into the frequency domain. You can see the noisy and noiseless signal FFT plots. I have set the SNR to zero. How come in the noisy signal you can still see the main lobe of the signal? If SNR is zero, shouldn't you be able to only see noise and not make out any part of the signal?

Answer 1

[David Goodmanson]

perhaps the snr is in dB, in which case signal level = noise level.