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National Historical Park

New Mexico

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Pecos National Historic Park, New Mexico

Tererro Mine

The most well-known of mining operations in the upper Pecos River watershed was the Tererro Mine located on a 19 acre site adjacent to the Pecos River, approximately 14 miles north of Pecos National Historical Park.

In 1881, a prospector named J.J. Case discovered an ore body containing relatively high grade copper, lead, and zinc ores near the confluence of Willow Creek with the Pecos River. Over the next two decades several shafts were dug and adits opened to explore these ore bodies, though the appropriate milling and metallurgical processes were not then available to exploit these resources economically(McDuff, 1993).

Subsequent discoveries of silver and gold ore, as well as significant advances in milling and metallurgical technologies for refining complex ores, altered the economics enough to make mining feasible by the mid-1920s. On January 1, 1927, the American Metal Company (a predecessor of Cyprus Amax Minerals Company) began mining production at the Tererro Mine, which soon supported the largest payroll in the State of New Mexico (McDuff, 1993).

From 1927 through May, 1939, approximately 2,293,000 tons of ore from the Tererro Mine were loaded on an aerial tramway and transported 12 miles to the El Molino mill located along Alamitos Creek near Pecos, New Mexico. This ore was refined to produce more than 440,000,000 pounds of zinc; 138,000,000 pounds of lead; 19,000,000 pounds of copper; 5,000,000 ounces of silver; and 178,000 ounces of gold. It was one of the better multiple ore producers operating in the United States from the late 1920s through the 1930s (McDuff, 1993).

Today, the land surface at the abandoned Tererro Mine consists of numerous unstabilized spoil and overburden piles located on a 19 acre site along Willow Creek and in the floodplain of the Pecos River.

Willow Creek flows across a portion of the waste piles before emptying into the Pecos River resulting in elevated zinc, lead, copper, and cadmium concentrations in Willow Creek and in the Pecos River below (Sinclair, 1990). O'Brien (1991) found elevated copper, zinc, selenium, and lead levels in brown trout (Salmo trutta) downstream from this site. In addition, the Lisboa Springs State Fish Hatchery, located 11.5 miles downstream from the Tererro Mine, has experienced major fish die-offs in raceways utilizing water from the Pecos River. It is possible that one of the factors related to these die-offs may be contaminants leaching from waste tailings piles near the site of the former Tererro Mine. These tailings are believed to be a source of high concentrations of zinc and other heavy metals periodically measured in surface flows and biota in the Pecos River (U.S. Fish and Wildlife Service, 1993).

While some minor drainage diversion work has recently been completed to divert surface runoff away from the waste rock piles, alternatives for site stabilization and remediation are currently being evaluated by Cyprus Amax Minerals Company and the New Mexico Environment Department (Johnnie Green, Cyprus Amax Minerals Company, and Stephen Wust, New Mexico Environment Department, pers. comm.).

Source National Park Service, Water Resources Division


McDuff, L.F. 1993. Terrero - the history of a New Mexico mining town. Suisun, California. 189 pp.

O'Brien, T.F. 1991. Investigation of trace element contamination from Tererro Mine waste, San Miguel County, New Mexico. Albuquerque , New Mexico : U.S. Fish and Wildlife Service. 47 PP.

Sinclair, S. 1990. Screening site inspection of Tererro Mine, San Miguel County, New Mexico. Santa Fe , New Mexico : New Mexico Environmental Improvement Division. 17 pp

U.S. Fish and Wildlife Service. 1993. Investigation of potential causes of periodic fish mortalities at Lisboa Springs State Fish Hatchery, Pecos , New Mexico . Albuquerque , New Mexico : New Mexico Ecological Services State Office. 75 pp.

Photo by David Muench

park maps subheading

The General park map handed out at the visitor center is not available.

For information about topographic maps, geologic maps, and geologic data sets, please see the geologic maps page.

photo album subheading

A geology photo album has not been prepared for this park.

For information on other photo collections featuring National Park geology, please see the Image Sources page.

books, videos, cds subheading

Currently, we do not have a listing for a park-specific geoscience book. The park's geology may be described in regional or state geology texts.

Please visit the Geology Books and Media webpage for additional sources such as text books, theme books, CD ROMs, and technical reports.

Parks and Plates: The Geology of Our National Parks, Monuments & Seashores.
Lillie, Robert J., 2005.
W.W. Norton and Company.
ISBN 0-393-92407-6
9" x 10.75", paperback, 550 pages, full color throughout

The spectacular geology in our national parks provides the answers to many questions about the Earth. The answers can be appreciated through plate tectonics, an exciting way to understand the ongoing natural processes that sculpt our landscape. Parks and Plates is a visual and scientific voyage of discovery!

Ordering from your National Park Cooperative Associations' bookstores helps to support programs in the parks. Please visit the bookstore locator for park books and much more.

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For information about permits that are required for conducting geologic research activities in National Parks, see the Permits Information page.

The NPS maintains a searchable data base of research needs that have been identified by parks.

A bibliography of geologic references is being prepared for each park through the Geologic Resources Evaluation Program (GRE). Please see the GRE website for more information and contacts.

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NPS Geology and Soils Partners

NRCS logoAssociation of American State Geologists
NRCS logoGeological Society of America
NRCS logoNatural Resource Conservation Service - Soils
USGS logo U.S. Geological Survey

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Currently, we do not have a listing for any park-specific geology education programs or activities.

General information about the park's education and intrepretive programs is available on the park's education webpage.

For resources and information on teaching geology using National Park examples, see the Students & Teachers pages.
updated on 01/04/2005  I   http://nature.nps.gov/geology/parks/peco/index.cfm   I  Email: Webmaster
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