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small, then a spatial composite grab sample of material from around the dump should suffice. If both weathered and unweathered materials are present, operator may be required to test representative samples of both. Sampling of un-mined material in a new operation demands special consideration, and will often require collection via core drilling. Sampling of representative material under these conditions requires detailed knowledge of the mine plan and the geology, including the orebody configuration and grades. By the time the orebody has been delineated, there will likely be plenty of representative drill core available for sampling. B. Types of Tests Static tests: Static tests determine only the quantities of minerals or elements in the rock without regard to leaching potential over time. Depending on the potential environmental impact, the Division will generally require the following two types of static tests: 1) Mineralogical analysis such as whole rock analysis. 2) Acid-base accounting to calculate the acid-generating potential based on the relative concentrations of carbon and sulfur (note: uranium mines will rarely possess sulfide minerals in quantities sufficient to cause a net acid generating situation, so ABA requirements will generally be less rigorous for operators of uranium mines). Accelerated weathering tests: DRMS will require some type of accelerated weathering test, such as the SPLP (Synthetic Precipitation Leaching Procedure; EPA method 1312, ASTM method D6234-98), MWMP (Meteoric Water Mobility Procedure; ASTM method E2242-02), or a sequential batch test (ASTM methods D-4793 or D-5284). The TCLP (Toxicity Characterization Leaching Procedure; EPA method 1311) is not appropriate for mine rock characterization. For 112 designated mining operations, or other sites that have potential to disturb acid or toxic-forming materials, the rigor of the accelerated weathering tests should be increased to something of longer duration. Examples of approved methods include conventional humidity cells (ASTM method D5744-07), modified humidity cells (ASTM method D5744-96), standardized column leach tests such as ASTM method 1995-C, or a Soxhlet reactor. The use of any accelerated weathering test will be subject to Division review and approval. The material to be tested will likely vary from one site to the next due to variability in lithology, mineralogy, geomorphology, mining and reclamation plans, hydrologic setting and other factors. The sampling and analysis plan should be submitted to DRMS for approval beforehand. The SPLP standard method calls for 100 grams of sample of -9.5 mm size fraction, agitated in 2 liters of solution for a liquid to solids ratio of 20:1. However, the USGS has developed a modified SPLP test that uses 50 grams of sample of -2.0 mm fraction in 1 liter that has been shown to produce nearly identical results. Therefore, either test would be acceptable to DRMS. If tailings are to be the subject of the geochemical evaluation, then the rock should be crushed'and screened even further such that the grain size of the rock closely approximates the grain size of the tailings. A grain size of -60 mesh, or -0.25 mm should suffice.