Enchemica

During the Water Working Group Meeting held on June 25, 2020, there was a request for more details about how nitrogen (N) chemical loads and concentrations were estimated in the block cave geochemistry and tailings solute models. The purpose of this memo is to provide these details and to serve as clarification to action item WR-20.

Resolution Copper plans to use sodium isopropyl xanthate (SIPX; C4H7OS2Na) as a collector agent for sulfide mineral processing. The purpose of this technical memorandum is to provide a summary of the use, properties, decomposition kinetics, and decomposition products for SIPX. This information is used to evaluate the environmental fate and transport characteristics of SIPX relevant to the tailings storage facility (TSF) for the Resolution Copper Project.

The chemical balance portions of the models share a set of common inputs for water chemistry. The purpose of this memo is to provide a description of those common inputs.

The purpose of this technical memorandum is to provide an updated description of the geochemical model of the block cave system.

Water balances models have been developed for each alternative. These water balance models have been augmented by the addition of chemical balances. The purpose of this memo is to provide a description of the predictions of the chemical balance and resulting solute chemistry for Alternative 6.

Water balances models have been developed for each alternative. These water balance models have been augmented by the addition of chemical balances. The purpose of this memo is to provide a description of the predictions of the chemical balance and resulting solute chemistry for Alternative 5.

Water balances models have been developed for each alternative. These water balance models have been augmented by the addition of chemical balances. The purpose of this memo is to provide a description of the predictions of the chemical balance and resulting solute chemistry for Alternative 4.

Water balances models have been developed for each alternative. These water balance models have been augmented by the addition of chemical balances. The purpose of this memo is to provide a description of the predictions of the chemical balance and resulting solute chemistry for Alternative 3.

Water balances models have been developed for each alternative. These water balance models have been augmented by the addition of chemical balances. The purpose of this memo is to provide a description of the predictions of the chemical balance and resulting solute chemistry for Alternative 2.

Email Address Created for Land Exchange Questions

The Southwestern Region Office of Lands and Minerals Management is overseeing and administering the land exchange and appraisal process which includes the 2,422-acre Oak Flat Federal Parcel. All questions about the land exchange and appraisal process should be emailed to SM.FS.rcexinfo@usda.gov

Programmatic Agreement Info

To comply with Section 106 of the National Historic Preservation Act, the Tonto National Forest developed a Programmatic Agreement (PA) and included it in Volume 5, Appendix O of the final EIS. The PA was created in cooperation with the Advisory Council on Historic Preservation, the State Historic Preservation Office, tribes and other consulting parties. The PA contains an agreed upon process for identifying, evaluating and addressing adverse effects to historic properties associated with this undertaking.

To review Volume 5 and the PA, Download Vol 5 PDF, 27 MB.

Forest Service Point of Contact

John Scaggs
Tonto National Forest
john.scaggs@usda.gov

Apache Leap Special Management Area
Apache Leap SMA website