ASTM D5526 is a very labor-intensive and cumbersome test method mimicking landfill conditions too. We used to perform this test too, but as ASTM D5511 is a more recent, optimized and reliable test method, we never run this testing anymore and always use ASTM D5511. The main difference between ASTM D5526 and ASTM D5511 is duration (6 months for ASTM D5526 versus 15-30 days for ASTM D5511) and acceleration factor used (1-10 for ASTM D5526 versus 10-100 for ASTM D5511).