Underground mining operations have had to deal with development challenges including drainage, ventilation, illumination and excavation support.
Water underground originates from the surface, oftentimes through porous or fissured rock masses, alluvial material, sand, gravel and limestone. Meteoric water from rain, snow and fog, connate water buried with rocks that contain it, and magmatic water originating from cooling magma and resulting rocks are some classifications defining water sources.
Mines throughout ÃÛèÖÖ±²¥ have met the challenges of dewatering workings through aggressive pumping systems.
The Magma Mine early on built a 1,200-gallon-per-minute pumping station at the 3,600-foot level. The Old Dominion Mine used deep-well turbines to bore holes removing water from the mine levels as a prerequisite to further development. The mines at Tombstone employed heavy Cornish pumps to mitigate flooding in the 1880s and 20 years later built two 1,500-gallon-per minute pumps at the 700-foot station to handle more than 2 million gallons of water daily.
People are also reading…
Challenges involving water acidity in copper mines include corrosion of mining equipment such as fittings, pipes, pumps and valves. Solutions including the use of lime as a neutralizing agent of acid water were used in the early 1900s. However, when mixed in an agitating tank and added to slurry in varying amounts, the lime compound would accumulate on the ditches and sumps.
Harrison M. Lavender was a renowned Phelps Dodge vice president in charge of Western Operations and the namesake of the Bisbee open pit mine development known as the Lavender Pit. He was successful in processing acid copper-bearing mine water that replaced lime mineralization. Mine water was passed through a series of 10-foot-long by 5-foot-wide and 5-foot-high water-proofed concrete boxes filled with scrap iron, which precipitated the copper while neutralizing the water acidity.
Ventilation, another challenge to successful underground mining operations, involved the need to manage accumulation of gases in workings including those of carbon monoxide, methane, hydrogen and nitrogen. These gases occur naturally in most rocks; however, in high concentrations, these can prove fatal to miners.
Firedamp, a combustible gas comprised of methane, is often found in coal mines. Blackdamp, a mixture of around 90% nitrogen and 15% carbon dioxide, is caused by combustible gases. Heavier than air, it is often found on the surface of a mine, reducing the oxygen content in the air and leading to the asphyxiation of miners in proximity.
Oftentimes mice or small birds were taken underground to measure levels of carbon monoxide due to their sensitivities to gases, hence the phrase “canary in a coal mine.†This practice was later replaced by electronic detectors.
Some early examples of mine ventilation in ÃÛèÖÖ±²¥ involved the Oatman district at the Tom Reed gold mine. Work at the 1,100 level in 1931 proved challenging with temperatures in excess of 103 degrees. Procurement of a No. 8 Sirocco fan driven by a 25-horsepower motor, delivering 31,000 cubic feet of air per minute, was installed at the bottom of the United Eastern shaft on the 950 level. A system of wooden control doors was also installed to moderate the air flow. Better air distribution, cooler temperatures resulting from the absorption of heat from exposed surfaces, and reduction of relative humidity resulted in improved working conditions.
Another example involved the 4,600-foot-deep Magma Mine installing an air-conditioning plant that required 494,310 kilowatt-hours for its monthly operation in November 1937. The refrigerating units were placed underground, relying on underground water source for cooling and pumps for circulating.
Other methods of ventilation included dust mitigation with bag filtering units and spray chambers around loading chutes, transfers and underground crushers. Today, small portable devices including anemometers and airflow meters use wind velocity as a means to test air quality and determine airflow in a mine, reducing the buildup of deadly gases.
Innovations in mine illumination have evolved from candles, oil and carbide lamps to the electric cap lamp consisting of a lamp attached to a miner’s cap connected by a flexible cord that draws current from a small storage battery attached to the miner’s belt. Battery power lasted 12 hours and was recharged after the miner’s shift. Permissible electric mine lamps included a safety feature that would prevent ignition of explosive methane and air mixtures in the event that the lamp bulb was broken.

Underground drilling with shaft cribbing seen at right.
A history of mine disasters in the United States in the early 20th century (25 alone in 1910), preceded by the 1907 Monongah Coal Mine disaster in West Virginia (considered the largest coal mine disaster in U.S. history with a documented 362 casualties), prompted congressional action.
The U.S. Bureau of Mines was established in an attempt to improve working conditions in mining operations across the country.
The Mine Safety Appliances Co. was tasked to create an improved and safer electric cap lamp. Thomas Edison was credited with having designed the Edison Cap Lamp, comprised of a rechargeable battery pack in a self-locking steel case. It included the safety feature of an electrical contact disconnect should the bulb break, enabling the tungsten filament to cool, so as to avoid igniting flammable gasses in the air.
Another safety concern involving underground mining is rock support for excavations. Early methods employed including timber post and cross-members installation to avoid cave-ins induced when conducting blasting and seismic loading. Many types of materials are used as support structures in mines including timber, concrete, stone, steel, brick and cast iron.
Treated timber for longevity with coal-tar creosote or zinc chloride has proven effective in shafts, adits, stations, air ways and track lines. Principle systems involving timbering include cribs (appears as a log house structure), square-sets (trusses constructed on vertical and horizontal lines) and stulls (timber props wedged between two walls of a stope as a framework to prevent cave-ins).
No doubt, underground mining practices evolved over the 20th century to facilitate the safety needs of the miner and the production of the mine site.

Waste filling in cut & fill stope.

Permissible methane detector manufactured by the Mine Safety Appliances Co.

Permissible electric signal lamp issued to the Concordia Electric Co. by the CEAG Ltd.

A "Sirocco" fan wheel

Square-set timbering on an inclined ore-body.

Cribbing or log-house structure used for underground mining support.

Schematic showing automatic pump control for high-level sump used for mine water drainage.

Edison cap lamp
Photos: The birth and life of San Manuel mine, smelter and town in 1950s-70s
Town of San Manuel

A pipe to carry concrete to the first 1,000 homes of San Manuel winds through a cholla forest in August, 1953. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
San Manuel copper mine, refinery, smelter

A miner drills into rock that is part of the San Manuel copper ore body in December, 1955. Explosive charges were place in the holes to blast the ore free.
San Manuel copper mine, refinery, smelter

The sleepy operation, support buildings and Shaft #1 at the San Manuel copper mine near the town of Tiger, Ariz., in 1953, after an investment of more than $100 million dollars by Magma Copper.
San Manuel copper mine, refinery, smelter

San Manuel copper mine Shaft #1 at Tiger in 1953. The townsite, in in the background, was demolished.
San Manuel copper mine, refinery, smelter

The head frame of the shaft at the San Manuel copper mine in 1952, just after Magma Copper secured a $94 million loan from the Reconstruction Finance Corp to dramatically expand the mine operation. Workers had joined Shafts 1 and 2 with 18,000 feet of horizontal tunnels at 1,475-feet-deep.
San Manuel copper mine, refinery, smelter

A miner drills into rock that is part of the San Manuel copper ore body in December, 1955. Explosive charges were place in the holes to blast the ore free.
San Manuel copper mine, refinery, smelter

The sleepy support buildings and Shift #1 at the San Manuel copper mine near the town of Tiger, Ariz., in 1952, prior to an investment of more than $100 million dollars by Magma Copper.
San Manuel copper mine, refinery, smelter

Miners get ready to plunge hundreds if not nearly 2,000 feet below the surface at the head frame of the shaft at the San Manuel copper mine in 1952, just after Magma Copper secured a $94 million loan from the Reconstruction Finance Corp to dramatically expand the mine operation.
San Manuel copper mine, refinery, smelter

Miners in a drift (tunnel), 1475-feet underground in the San Manuel copper mine, unload shoring timber from mine cars in April, 1954.
San Manuel copper mine and smelter

The head frames of the two 2,950-feet deep production shafts into the San Manuel ore body in 1955.
San Manuel copper mine and smelter, 1955

San Manuel was once the largest underground copper mine in North America. Magma Copper began commercial underground mining in San Manuel in 1956, after sinking two 2,950-foot shafts into the San Manuel ore body in 1953.
San Manuel copper mine and smelter

Ore milling operations at San Manuel copper mine in 1955. The mine began commercial processing of ore in 1956.
San Manuel copper mine and smelter

Magma Copper managers interviewing a potential mine employee in 1955 as the company was adding a smelter operation.
San Manuel copper mine and smelter

Ore milling operations at San Manuel copper mine in 1955. The mine began commercial processing of ore in 1956.
San Manuel copper mine, refinery, smelter

Piers hold up an ore conveyor under construction at the San Manuel mine in 1954.
San Manuel copper mine, refinery, smelter

Mill concentrator building under construction in San Manuel in 1954. It was 700-feet long and 300-feet wide.
San Manuel copper mine, refinery, smelter

Huge ore storage bins atop the 185-foot tall head frames atop the 2,950-foot deep production shafts at San Manuel mine in 1955.
San Manuel copper mine, refinery, smelter

Magma Copper workers blast rock to make way for a 2,950 foot production shaft to access the San Manuel copper ore body in August, 1953.
San Manuel copper mine, refinery, smelter

Wesley P. Goss, president and general manager of Magma Copper, in 1952,
San Manuel copper mine and smelter

The new copper smelter at San Manuel in December, 1955. At bottom right is the casting wheel, which holds 22 anodes, each weighing 700 pounds. Above is the anode furnace and along the right side to the rear are three converters. Jutting out at left is the reverberatory furnace. The ladle hanging from the gantry crane in the background can hold 30 tons of molten copper.
San Manuel copper mine and smelter

Managers at the new control center for the San Manuel smelter complex in 1955.
San Manuel copper mine and smelter

Ore milling operations at San Manuel copper mine in 1955. The mine began commercial processing of ore in 1956.
San Manuel copper mine and smelter

A horizontal mine passage in the San Manuel copper mine in 1955.
San Manuel copper mine and smelter

Eight rod mills, right, and 16 ball mills in the 850-foot concentrator building at the San Manuel Mine operation in December, 1955. Steel rods and balls reduce the crusshed copper ore to granular consistency preceding the flotation process.
San Manuel copper mine and smelter

Thickeners are 300-foot basins in which processed concentrate is dried to a moisture content of seven percent. The concentrate averages 27-percent copper. It will be conveyed to the smelter for final reduction.
San Manuel copper mine and smelter

Rail line to the crusher, concentrator and smelter at San Manuel in 1955. The ore traveled nine mines from the underground mine to processing.
San Manuel copper mine and smelter

Ore cars are inverted at the top of the head frame, dumping the ore into huge storage bins that feed ore cars going to the crushers.
San Manuel copper mine and smelter

The new flotation process in the San Manuel copper mine. Finely-ground ore leaving the concentrators enters the flotation process, where it is mixed with water and reagents move the copper to the surface and tailings to the bottom, where they are carried off underground.
San Manuel copper mine and smelter

The head frames of the two 2,950-feet deep production shafts into the San Manuel ore body in 1955.
San Manuel copper mine and smelter

The head frame of the San Manuel Mine. Ore cars are brought up from the shaft and dumped into the storage bins feeding rail cars taking the copper ore to the crushers, the first stage of the copper extraction process.
San Manuel copper mine, refinery, smelter

Sparks fly from blast furnaces in San Manuel in 1975 as copper concentrate is smelted at 2,700-degrees, which turns other elements like iron into slag to be discarded. Beginning in 1975, Magma Copper recovered the sulfur dioxide emissions from the smelter and converted it to sulfuric acid.
San Manuel copper mine, refinery, smelter

Shown in 1975, molten copper as much as 99-percent pure emerges from the San Manuel smelter and poured into molds to create 700-pound anodes that were transported to a refinery to remove other impurities, like gold and silver.
San Manuel copper mine, refinery, smelter

In this photo, probably ca. 1950s, molten copper from the San Manuel smelter, right, is poured into molds which cool to make anodes (being lifted at right), which are further-refined to better-than 99-percent pure.
San Manuel copper mine, refinery, smelter

The completed crusher, concentrator and smelter at San Manuel in 1955. The company town of San Manuel rises in the background.
San Manuel copper mine, refinery, smelter

A Magma Copper handout graphic showing ore flow for the San Manuel smelter.
San Manuel copper mine, refinery, smelter

A miner standing in a tunnel more than 1,000 feet deep in the San Manuel, pauses after a electric ore cars carrying 185 tons of rock passed by in 1975.
San Manuel copper mine, refinery, smelter

San Manuel smelter at full tilt, probably in the 1970s.
San Manuel copper mine, refinery, smelter

The crusher, concentrator and smelter at San Manuel in 1971, after a $200 million explansion of the facility. The smelter got a second smoke stack. In the background, the company town of San Manuel got another 200 houses.
San Manuel copper mine, refinery, smelter

An electrolytic refinery to produce refined copper from copper anodes at San Manuel and was completed in December, 1971.
Town of San Manuel

Townsite for the mining company town of San Manuel in Pinal County north of ÃÛèÖÖ±²¥ in 1953. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

Superintendent Robert Fleming of the Del E. Webb Construction Co. and engineer John Stephens stand on the site of the San Manuel business district in August, 1953. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

The caption is this bandout photo read, "How can engineers do surveying in a land like this?" Engineer John Stephens at the San Manuel townsite prior to clearing. The mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

A map of the mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

Pinal County supervisors Jay Bateman, left, Frank Williams, and Joy Spray, far right, meet with Del E. Webb general manager L.C. Jacobson at the San Manuel townsite under construction in 1954. Magma Copper Company worked Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people,
Town of San Manuel

The mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

A brochure for the mining company town of San Manuel under construction ca. 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

A brochure for the mining company town of San Manuel under construction ca. 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

A food truck feeds workers clearing the site for the state's "newest city" of San Manuel in Aug, 1953. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

The mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

Deserted streets of San Manuel in November, 1954, prior to rental to mine workers and their families. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

Avenue A in the mining company town of San Manuel under construction in 1954. Homes had masonry walls, "modern design" and landscaped yards. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

Tommy Blank was the first barber in the mining company town of San Manuel in 1953. He slept in the shop for a few months until his house was built. He raised his family in San Manuel, working as a barber for Magma Copper Company for 34 years until retiring in 1988. His wife, Helen, was a Harvey Girl at the Grand Canyon and went to work in healthcare for Pinal County. They watched San Manuel boom, and finally bust as the mine and refinery were closed in 2003. His granddaughter noted that Tommy served in the U.S. Navy in the South Pacific in WW II and survived a Japanese kamikaze attack.
Town of San Manuel

A cul du sac is paved outside the rental office at the mining company town of San Manuel in December, 1953. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
Town of San Manuel

Crews grade the streets of the mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people, The mining company town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

Mr. and Mrs. Jimmy Cabral of Clifton, with son Marin in December, 1953, would be become some of the first residents of the mining company town of San Manuel. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people. The first 1,000 homes were intended for "defense workers of San Manuel Copper Company," since a large chunk of money to build the town and the mine came from the federal goverment. Initially, residents could only rent homes for the first two years. Then they would have the option to purchase then.
Town of San Manuel

An electric substation under construction to supply power to the mine, smelter, and town of San Manuel under construction in 1954. Magma Copper Company worked with Del E. Webb Construction Company of Phoenix to create Webb's first "master-planned community" in ÃÛèÖÖ±²¥. M-O-W Aldon Construction of California was hired to build homes for 8,000 people.
A special thank you to local ÃÛèÖÖ±²¥an Bruce McDermaid, who provided the author with the mine safety lamps of which several images are displayed in this article.
William Ascarza is an archivist, historian and author of seven books available for purchase online and at select bookstores. These include his latest, “In Search of Fortunes: A Look at the History of ÃÛèÖÖ±²¥ Mining,” available through M.T. Publishing Co. His other books are “Chiricahua Mountains: History and Nature,” “Southeastern ÃÛèÖÖ±²¥ Mining Towns,” “Zenith on the Horizon: An Encyclopedic Look at the ÃÛèÖÖ±²¥ Mountains from A to Z,” “ÃÛèÖÖ±²¥ Mountains,” “ÃÛèÖÖ±²¥-Sonora Desert Museum” with Peggy Larson and “Sentinel to the North: Exploring the Tortolita Mountains.” Email William Ascarza for a signed copy of his publications at AZMiningHistory@gmail.com