Rosemont Copper has met extensive government requirements to improve its mine proposal, and so it is time to accept that the mine will be built. We respect the laws, though flawed, that permit mining in a national forest in a region with limited water.

Nearly six years have passed since the federal government began studying Rosemont’s plan to dig a pit in the Coronado National Forest nearly 2½ times the size of the University of Arizona’s 391-acre campus. That’s been adequate to assess the considerable environmental dangers and to devise plans to limit them. And while Rosemont still needs to convince the Army Corps of Engineers it can comply with the Clean Water Act, we believe the company will continue to make accommodations and prevail.

Federal law, from the start, has broadly supported Rosemont’s intentions. Mining is permitted on taxpayer-owned land in the West, even in places as environmentally significant as the Santa Rita Mountains. We do not agree with that aspect of the law, but Congress has shown little inclination to change it.

The Forest Service’s primary mission has been to analyze the mine’s impact on everything from water, air and wildlife to Native American cultural resources and the nearby telescopes.

The mine plan has been studied by hydrologists, biologists, archaeologists, air-quality experts, engineers and other scientists. Sixteen government agencies participated. All told, a few thousand people attended 16 public meetings. More than 36,000 comments were submitted to the Forest Service.

As a result of that review, Rosemont’s plan — including the precise footprint of its mine — has been revised to avoid some impacts. It includes more mitigation and more monitoring once the mine is operating. Rosemont says it will spend an additional $300 million to $400 million to meet those requirements.

The most recent mine plan tentatively endorsed by Coronado National Forest Supervisor Jim Upchurch is much better than the one proposed in 2008. That is a credit to public scrutiny by opponents such as Save the Scenic Santa Ritas and to the review process, which, while lengthy, has been appropriate for a project of such size and complexity. Now, negotiations between governments and the company should proceed toward final approval.

We believe that Rosemont will be able to meet its legal and regulatory obligations. However, that does not mean that building this mine is wise. Our primary concern is that, by law, the review has been so tightly focused on Rosemont that it misses the larger and more critical problems of Arizona’s fragile surface water and dwindling groundwater.

Under state law, mines essentially have the right to use groundwater even in an area such as the Santa Cruz Valley, where pumping exceeds recharge by about 22,000 acre-feet annually. That’s enough to supply about 44,000 families. Rosemont has land near Sahuarita for wells and has a state permit to pump 6,000 acre-feet annually over the mountains to the mine site.

Rosemont is doing more than law requires when it comes to groundwater. It has offered to pay to extend to Green Valley the Central Arizona Project line that already brings Colorado River water to Tucson. The Community Water Co. of Green Valley has an annual allocation of 2,858 acre-feet of Colorado River water but cannot reasonably afford to have it delivered. If Community Water can get CAP water, that could be recharged and help offset groundwater use.

On the east side of the Santa Rita Mountains, Rosemont has agreed to purchase the 1,200-acre Sonoita Creek Ranch, which has the right to use 590 acre-feet of water annually. Ownership would be transferred to the Arizona Game and Fish Department, which would end its use for grazing or agriculture and prohibit future development.

Rosemont has been buying and recharging Colorado River water — 45,000 acre-feet — although most of that is occurring far to the north in Marana, where it does not help the Santa Cruz Valley’s groundwater problem. There is no plan to move that stored water to the valley, but the proposed CAP pipeline extension to Green Valley would have the capacity to carry it. Whether recharge occurs far from or near the Santa Cruz Valley, Rosemont expects to recharge 105 percent of the mine’s water use.

These and related water-mitigation measures are admirable. The trouble is that limiting the discussion to Rosemont misses the much bigger issue. Arizona has a serious mining problem — the mining of water. (See accompanying story for those details.)

There are many Rosemont issues — such as air quality, the safety of Arizona Highway 83 once mine trucks began traveling on it, and the impact of night lighting on nearby telescopes — that have concerned us about the mine plan. But we are satisfied that over the years of analysis and negotiation, those have been mitigated to the extent reasonably possible.

If monitoring shows the mine is causing unforeseen damage, government regulators must act quickly to stop or ameliorate it. All monitoring results must be readily made public; a big chunk of the land, after all, is owned by taxpayers.

Proponents of the mine have tried to keep the debate focused on the economic impacts. Rosemont, during its 20- to 25-year life, would provide about 430 jobs at an average of $60,000 each, before benefits. The total number is tiny compared with the 361,000 jobs in Pima County. However, the pay is large compared with our per capita income of $25,525. Also, Rosemont would represent private-sector diversity in a region where the few truly large employers are nearly all governments. The case for jobs is important.

We support Rosemont’s efforts under the law and support its plan, mindful that the review process has worked and that public and government scrutiny has been effective to ensure the best practical result. It’s time to move ahead.