So, I haven't worked on Canadian projects at all, but I've done a decent amount of industrial projects in the US (or at least using US codes) that encountered similar issues.
We generally used a number of different criteria:
1) We'd create one gravity load check for the maximum gravity load. We usually called this the "hydrostatic test" load case. But, we never checked this for lateral because these were generally one time short term loads. And, the probability that an earthquake or severe wind storm would hit at that same time is astronomically low.
2) Most of the time, we'd use the "normal operating" weight of the structure for lateral load. The only caution I would use with this is if you think it likely that the bin could spent a couple of months per year fully filled. If that's possible, then I'd probably use the full load.... Or, a "Max Operating" type load which is close to fully. If it's unlikely to happen for more than a week or so at a time then I'd say that you can probably use a "normal operating load" instead.
3) We often had an "empty" load that we'd use with wind to check overturning. With the idea that the bin may sit empty for months at a time when that facility went unused.
