I wondered to what extent they know the size and shape of the cavern at any given time and what they use to monitor it. The answer is apparently sonar, and ther

I wondered to what extent they know the size and shape of the cavern at any given time and what they use to monitor it. The answer is apparently sonar, and there are some pretty pictures here: https://digital.library.unt.edu/ark:/67531/metadc840493/m2/1/high_res_d/1028903.pdf https://digital.library.unt.edu/ark:/67531/metadc840493/m2/1...