The maximum acceptable concentration (MAC) of fluoride ions in drinking water is 1.5 ppm.

In Dublin, California, a malfunction occurred in the fluoridation equipment caused fluoride levels to rise as high as 200 ppm. This resulted in 23 people becoming ill. 

During the malfunction, 628 kg of fluoride ions where injected into a storage tank of water.

Given that the resulting concentration was 200 ppm, calculate the volume, in ML, of the water storage tank.