Physicomechanical Assessments and Heavy Metals’ Leaching Potential of Modified Asphalt Binders Incorporating Crumb Rubber and Tin Slag Powders

Table 4

Metals’ hazardous waste parameters by the US EPA [27].

Metals	Regulatory level (ppm)
Arsenic (As)	5.0
Barium (Ba)	100.0
Cadmium (Cd)	1.0
Chromium (Cr)	5.0
Lead (Pb)	5.0
Mercury (Hg)	0.2
Selenium (Se)	1.0
Silver (Ag)	5.0