UMass EWRE Program

MINEQL Resources for CEE 680



We are currently using Version 4.6 in CEE 680, which is compatible with Windows 10 and earlier MS platforms.  For those who wish to purchase their own version, visit the commercial website:


For many years Version 3.01 was available for free download, and as a result it is still widely used.



Software Manual



Chemical Species

·       Type-I Species: soluble species that comprise the basic components of the solution and its solutes.  These must be a collection of independent species.  Species that are merely combinations of previously specified Type-I species should not be included.

·       Type-II Species: aqueous complexes that form from the Type-I species.

·       Type-III Species: solids or other substances with fixed activity (e.g., precipitates that never completely dissolve, atmospheric gases, pH in a pH-controlled environment)

·       Type-IV Species: precipitates that could become completely dissolved and therefore go from an activity of one to zero

·       Type-V Species: substances that could precipitate, but do not yet exist as a precipitate

·       Type-VI Species: substances that are not considered in the calculations




Simple Acid/Base composition example for version 4.6 and version 3.01.