Characterization of Dar Bouaazza’s Mine Tailings Using Xrf, Acid-Base Accounting, And Leaching Tests (Taza Province, Morocco)

The present work evaluates the potential of Dar Bouaazza's mine tailings, located in Taza province Morocco, to generate acid mine drainage. In this regard, four samples (R2, R3, R6 and R7) were collected from the wastes left from previous mining operations. X-Ray Fluorescence (XRF) analyses revealed a predominance of lead (Pb) concentrations reaching 44.5% and Sulfur (S) contents ranging from 2.6% to 12.9%, suggesting the presence of sulfide minerals prone to oxidation. Static Acid-Base Accounting (ABA) tests showed high Acid-generation Potential (AP) values between 82 and 397 KgCaCCb/ton and low Neutralization Potential (NP). This lead to strong negative Net Neutralization Potential (NNP), classifying these tailings as acid generating, that causes a risk of Acid Mine Drainage (AMD). Furthermore, kinetic leaching tests using US RPA TCLP and French standards confirmed the presence of high lead concentrations, especially under acidic conditions, exceeding environmental standards. However, copper and zinc concentrations were lower, while arsenic showed increased solubility in neutral leaching conditions. Iron levels, on the other hand, remained within acceptable limits. The integration of all these tests showed significant environmental risks linked with Bouaazza's mine tailings.