By Jack Caldwell - Mining Engineer - Robertson GeoConsultants

The Wisconsin legislature has just posted a proposed new law on mining in the state. The full document is available at this link. At 191 pages it is not a short read; but it is a must-read. And it is a fascinating read. It is serious and sometimes frivolous. Consider these sections that caught my eye on scanning the document:

(b) Buildings and other structures will be painted and maintained in a manner that is visually compatible with the surrounding vegetational and earth conditions, except that if a building or other structure cannot be painted and maintained in a manner that is visually compatible or if painting and maintaining a building or other structure in a manner that is visually compatible would cause safety concerns, the building or structure will be made as visually inconspicuous as is practicable.

(h) Where practicable, elevation differences in water−based transport systems will be used for gravity flows to minimize pumping facilities and pressures.

(b) At the conclusion of mining activity, each tunnel, shaft, and other underground opening will be sealed in a manner that will prevent seepage of water in amounts that may be expected to create a safety, health, or environmental hazard, unless the applicant demonstrates alternative uses for the tunnel, shaft, or other underground opening that do not endanger public health or safety and that conform to applicable environmental protection and mine safety laws and rules.

More seriously, I recommend to anyone involved with the design, operation, or closure of a tailings facility, waste rock dump, or heap leach pad that you read Section 295.51 and following ( see pages 94 and following.)

This is as good a list of things to do as any I have ever seen–or compiled myself. There are copious clear definitions of almost all terms we use; there are lists of things to measure and characterize; there are specifics of what should be in the reports you have to compile; and there are specifics on the cost you have to provide. Here is just a small example:

(r) Data regarding the safety factors of tailings basin embankments, considering the following, on a case−by−case basis:

1. Geology of the mining waste site including type and homogeneity of the foundation.

2. Materials and methods to be used for embankment construction.

3. Physical and chemical characteristics of the mining waste as deposited and predicted changes through time.

4. The potential area to be affected in case of failure, considering land use and the surrounding environment.

5. Requirements of the mine safety and health administration of the federal department of labor.

Most of it constitutes what I may term best practice in mine waste disposal. But this is the most comprehensive listing I have seen. Although at times it can be demanding. Consider the implied closure criterion “return the area affected by mining to its original state” as in this clause:

(3) If it is physically or economically impracticable or environmentally or socially undesirable for the reclamation process to return the area affected by mining to its original state, the applicant shall provide, in the reclamation plan, the reasons it would be impracticable or undesirable and a discussion of alternative conditions and uses to which the affected area can be put.

That is a major task called for.

Maybe we can start a long discussion ofthe implications of this proposed law on the design, construction, and operation of mine tailings, waste rock, and heap leach facilities.