Critical accounting estimates	Uncorrected differences
Overall, we are satisfied with the reasonability of critical accounting estimates.	We did not identify differences that remain uncorrected.
The critical areas of estimates relate to: Post- Employment Benefits, valuation of accounts receivable including taxes and payments-in-lieu of taxes and trade and other receivables, liability for landfill post closure costs and carrying value of tangible capital assets and other non-financial assets.	Control deficiencies
See pages 6 - 9.	We did not identify any control deficiencies that we determined to be significant deficiencies in internal control over financial reporting.