Soda Ash Residue & Inconclusive Research

[PoolChallenged]

I've newly assumed responsibilities for our 34,000 gal community pool.

Approx 3 weeks ago, previous responsible individual dumped 50 lbs of soda ash (sodium carbonate) directly into the pool. Much of it has either dissolved or been vacuumed out; however, there is a white residue on pool bottom that I assume is undissolved soda ash.

Test results (last 7 days):
Chlorine: 2-3
pH: 7.6-7.9
TA: 70-80
CYA: 0
Calcium Hardness: 210-340
Water clarity: Clear

I would have expected excess soda ash to create cloudiness and dissolve over time, neither which is happening.

What can I do to eliminate the remaining soda ash?