Added way too much chalk to Stout

Question for you all. I am making a dry stout and, for the first time, added some salts (just got my Ward Labs water sample).

I was supposed to add about 2 grams of CaCO3, but my scale was accidentally set to ounces, and I ended up dumping about 1 ounce (!) of it into my mash before I caught myself. Basically, I've got way too much Calcium and HCO3 in my brew.

What's this going to do to my beer? Should I keep brewing, or save myself hours of effort and weeks of uncertainty and just dump it?

The good thing is that chalk is VERY ineffective at adding alkalinity and raising mash pH. So its possible that there is little to no adverse effect here.

If your water has really low alkalinity and you are brewing a grist that needs some alkalinity, I suggest finding some Pickling Lime and learning to use that for adding alkalinity. It works very effectively. Unfortunately if you miscalculate with a Lime dose like was done with the chalk, the beer would be f'ed and it would be time to toss it. You don't have that worry with chalk.

Your stout should still be OK in the case of this chalk overdose!

I ended up erring on the side of caution and dumped it. Calculated Ca+ at over 300 ppm and HCO3 at close to 500. Ran up to the LHBS and grabbed more grains, although I had to use Briess Roasted Barley instead of Crisp Black Barley. Just another trial in my Stout curse.