the first colonial salt-making operation in Virginia was on Smith Island
Source: Library of Congress, A map of the most inhabited part of Virginia containing the whole province of Maryland with part of Pensilvania, New Jersey and North Carolina. Drawn by Joshua Fry & Peter Jefferson in 1751
Virginia has plenty of salt on its eastern edge, in solution with seawater of the Atlantic Ocean. The state also has buried deposits of salt on its western edge, remnants of the Sauk sea that filled the Central Appalachian Basin 350 million years ago.
Human use of salt preceded the arrival of European colonists. Hernando DeSoto's expedition between 1538-1543 recorded Native Americans using salt to flavor food, and manufacturing salt as an item for trade. Tribes made salt by various techniques, including boiling saline water by placing hot rocks into clay pans:1
Native Americans in Virginia smoked their fish and deer/bear/elk meat, rather than used salt to preserve food.. The Algonquians who controlled the Tidewater region may have used salt, but there is no evidence that they boiled seawater and exchanged salt with Siouan-speaking and Iroquoian-speaking tribes west of the Fall Line. Those western tribes obtained whatever salt they used from natural saline springs, which carry some of the buried deposits of salt to the surface.
The Hernando Moyano expedition into southwestern Virginia in 1567 attacked a Native American settlement on the Holston River (perhaps at the modern town of Saltville in Smyth County) that produced salt from natural brine springs. How the Chiscas used that salt in the 16th Century, or traded it with others, is unclear.
Large-scale salt production by Native American tribes in Eastern North America is documented after colonial settlement created a demand for salt. In the 1600's, the Tunica in Louisiana and the Onondaga tribe in New York boiled brine from salt springs to make enough salt for exchange with Europeans.
In 1755, after the Shawnee captured Mary Draper Ingles from a site on or near the modern campus of Virginia Tech, the raiding party stopped on the way home to make salt from a brine spring on the Kanawha River. Mary Draper Ingles was later taken to Big Bone Lick in Kentucky to make salt, 500 miles away from Blacksburg.
Her long journey home to safety from that site, walking upstream perhaps 400 miles in about 6 weeks, is a dramatic tale of personal endurance. Her trip was so lengthy because she had been carried to a site where salt attracted animals that could be hunted, and where salt could be manufactured for trading with frontier settlers.2
Mary Draper Ingles was captured in 1755 on the New River (black X) and carried to Big Bone Lick on the Ohio River (red X)
Source: ESRI, ArcGIS Online
For the English in Virginia, salt was more than a condiment. It was essential for preserving food in the days before refrigeration. After the Sea Venture was shipwrecked on Bermuda during its voyage to Jamestown in 1609, the castaways built two replacement ships and completed the journey in 1610. They made salt on Bermuda and used it to preserve meat from the wild hogs caught on the island. The "powdered" (salted) pork helped sustain nearly 150 travelers for what ended up being a two-week trip between Bermuda and Jamestown.3
Colonists used indentured servants (and later slaves) to boil kettles of brackish water to drive off the water as steam, precipitating a crust of mineralized salt. The technology dates back to the days of Romans; the word "salary" is derived from paying soldiers enough to purchase salt. Lewis and Clark made salt by boiling Pacific Ocean water in kettles in the winter of 1805-1806, after they crossed the continent and reached the Oregon coast.4
Lewis and Clark used the same technique in 1805-1806 as the English colonists in Virginia - boil seawater to precipitate salt
Source: National Park Service - Lewis and Clark National Historic Park, Frequently Asked Questions
The first major colonial salt-making operation in Virginia was started by Sir Thomas Dale in 1614. Dale, the marshal of the colony responsible for military defense and discipline, sent colonists to Smith's Island on the southern tip of the Eastern Shore to make salt.
He sent indentured servants to the eastern side of the Eastern Shore ("seaside") to boil Atlantic Ocean water and precipitate salt. In the ocean, the water includes 35 parts per thousand (ppt) of sodium chloride (NaCl), with the NA+ and Cl- ions in solution. On the western side of the peninsula ("bayside"), fresh water runoff from the Susquehanna, Potomac, and other rivers dilutes the salinity of the seawater that enters the estuary between Cape Charles and Cape Henry.
boiling water from the Atlantic Ocean produced more salt than boiling less-saline water in the Chesapeake Bay or on the James/York/Rappahannock/Potomac rivers
Source: US Geological Survey, Simulation of Groundwater-Level and Salinity Changes in the Eastern Shore, Virginia (Figure 17)
The concentration of salt drops upstream until water on the surface is "fresh" (with less than 0.5ppt) on the James River near Jamestown. When the colonists chose to settle at Jamestown in May, 1607, the water in the river may have been fresh. As runoff declined during the summer, saltier water may have intruded upstream from the Chesapeake Bay. An excess of salt, imbibed because of the subtle change in water quality that summer, could have damaged the health of the colonists and been one reason for the high number of deaths at Jamestown starting in August.5
English colonists desired salt to improve the taste of food, and it was essential for preserving pork that might be stored in barrels after killing hogs on Bermuda. In 1614, Dale's colonists set up a salt-production base on the Eastern Shore on Smith's Island, and stayed there when not manning the kettles.
One traditional story about the Eastern Shore in that their base camp became known as the "plantation." That name is still applied to the creek next to the Town of Cape Charles.
tradition says Sir Thomas Dale's saltmakers lived on Plantation Creek, where a trip across the Chesapeake Bay to Jamestown was easier
Source: ESRI, ArcGIS Online
Walking back and forth from a bayside location to Smith's Island on the seaside of the Eastern Shore would have required much of a day. The workers had to add wood constantly to the fires boiling salt water, so some workers must have stayed on Smith's Island throughout the salt-making process while others may have stayed at the "plantation."
Locating the "plantation" on the Chesapeake Bay side of the Eastern Shore made it harder for the saltmakers to get to work on Smith's Island, bit easier for ships to bring supplies to the workers. A trip from Jamestown to Plantation Creek inolved a routine journey across the relatively-protected waters of the Chesapeake Bay. Sending supplies directly to Smith Island would have required traveling into the more-hazardous currents and winds of the Atlantic Ocean.
Saltmakers boiled 250-300 gallons of seawater in large kettles, evaporating the water to produce salt. The salt manufacturing operation required collection of driftwood and perhaps cutting some nearby trees for fuel. The saltmakers were not entrpreneurs working for themselves. They were indentured servants working for the Virginia Company, which owned the colony until 1624.
Making salt at Smith Island was not a fun camping expedition. The workers may have named the isolated salt-making site "Dale's Gift" satirically, because it was so far from the protection and social connections of Jamestown itself. Colonial leaders had idealistic visions of manufacturing enough salt to preserve fish for shipment to Caribbean islands and back to England, but salt production at Dale's Gift lasted less than four years and never produced enough salt to meet all the needs of the colonists in Virginia.
In 1620, a new set of saltmakers were sent to the Eastern Shore. Before abandoning that effort they tried to make salt through solar evaporation in shallow ponds lined with clay - a technique identified in 1613, when Samuel Argall first explored the area and reported:6
by 1622, colonists had expanded from the James River to create Dale's Gift and other settlements on the Eastern Shore
Source: Nell Marion Nugent, Cavaliers and Pioneers; Abstracts of Virginia Land Patents and Grants, 1623-1800 (opposite p.224)
Later efforts in the 17th Century to make salt from seawater also were based on the Atlantic Ocean side of the Eastern Shore ("sea side" in local jargon), where salinity was higher than on the "bay side." In 1660, the General Assembly promised Edmund Scarborough (Scarborough) a monopoly on salt production, with a ban on competition from imports, if he could produce 800 bushels of salt. The bar was set too high and Scarborough's arrogant behavior cost him political support from other members of the Virginia gentry, so he lost his monopoly after failing to produce enough salt.7
Col. Edmund Scarborough made salt at Gargaphia Plantation (red X) in the 1660's
(today, the place name has been modified to Gargathy Bay and Gargathy Creek)
Source: ESRI, ArcGIS Online
Gargaphia Plantation, site of Col. Edmund Scarborough's saltmaking operations, was recorded as "Scharburgs Gargaphra" in 1670
Source: Library of Congress, Virginia and Maryland as it is planted and inhabited this present year 1670 (by Augustine Herrman)
It required substantial labor to collect the firewood, feed the fire, and boil water in kettles, then scrape the salt out; importing salt produced by slaves on Caribbean islands was less expensive than making salt on the Eastern Shore. During the Revolutionary War, the Americans first established a boycott that stopped importation, and later the British warships blocked most of the trade with the Caribbean.
Virginians struggled to preserve enough beef and pork to feed their families, especially on Piedmont plantations with large numbers of slaves. At the start of the American Revolution, merchants hoarded salt and prices climbed until the Virginia General Assembly established a state monopoly and imposed price controls in 1776. The Virginia Convention (which governed the colony after until the state declared independence) proposed creating 10 state-owned saltworks, with shallow ponds to be constructed for evaporating the brine and precipitating salt.
in 1775, the Virginia Committee of Safety sought to increase the availability of salt by allowing a free market, but price controls were imposed in 1776
Source: Virginia Gazette (Purdie), December 8, 1775 (posted online by Colonial Williamsburg)
Either out of ignorance regarding salinity differences or fear of British attack, most of the saltworks were located within the Chesapeake Bay rather than on the sea side of the Eastern Shore. Evaporation efforts failed to generate more than a token amount of salt, and plans to purchase metal pans and boil brackish water floundered over the difficulty of acquiring the pans. The most effective solution turned out to be importing salt from Bermuda and the Caribbean islands via fast ships that could avoid the British blockade.8
Inland from Tidewater, there are no salt lakes in Virginia equivalent to the Great Salt Lake in Utah because there are no depressions in Virginia without an outlet. Just as in Utah, rainfall leaches minerals out of the soil in Virginia, but in Virginia streams carry the dissolved ions downstream all the way to the Atlantic Ocean or Gulf of Mexico.
There are a few places in Virginia where salt springs from underground salt beds create "salt licks" on the surface of the ground. Animals seek out the minerals at those locations, and for perhaps 15,000 years hunters have been well aware of the locations where salt from underground formations is carried by groundwater to the surface. Mastodons and other large mammals utilized salty marshes that later were the site of the Chiscas and then today's Saltville; "Big Lick" was an animal concentration point long before it became the modern city of Roanoke.
the Big Lick station on the Virginia and Tennessee Railroad (which developed into the city of Roanoke) was named for mineral-rich springs
Source: Library of Congress, Roanoke County, Virginia (1865?)
The few natural salt licks in the western part of the state were identified early by colonial explorers. Thomas Batts and Robert Fallam (or Fellows) explored across the Blue Ridge in 1671, discovering the New River before turning back. Native Americans told them that if they had traveled further beyond the mountains, they would have reached where others "lived on a plain level, from whence came abundance of salt." The Chiscas may have been replaced by Cherokees a century after Hernando Moyano's attack, but the salt springs on the North Fork of Holston (now Saltville) were still being utilized.9
In 1750, Dr. Thomas Walker traveled past "the great Lick on A Branch of the Staunton" River. That site, later called "Big Lick," is now in downtown Roanoke. Dr. Walker noted how the mineralized soil attracted game, and how the early settlers had wasted that asset:10
Before the buffaloes, there were mastodons seeking out the mineral springs in southwestern Virginia. Thomas Jefferson saw mastodon bones dug up at Saltville and from a salt lick in Kentucky. He was not aware of the salt springs further west on the Kanawha River, but in Notes on Virginia he recorded the existence of three salt springs in Kentucky as well as the one at Saltville on the Holston River:11
Virginia first major commercial production west of the Alleghenies was on the Kanawha River near modern-day Charleston, before the creation of West Virginia. The same springs where Mary Draper Ingles was forced to make salt in 1755 were converted into an industrial production site starting in 1797.
The westward expansion of population created a strong demand for salt used to preserve meat and butter, in the days before refrigeration. Development of the salt deposits on a 15-mile stretch of the Kanawha River created an industrial complex in western Virginia. The manufactured product (salt) was shipped west to customers all the way to New Orleans, not eastward to the traditional Tidewater port cities of Alexandria, Fredericksburg, Richmond, or Petersburg.
Virginia's first industrial-scale saltworks began in 1797 on the Kanawha River near modern-day Charleston, West Virginia
Source: Library of Congress, Map of the "Kanawha City" estates, Kanawha County, West Virginia, United States of America (1875)
Within 14 years, wells were drilled over 400 feet deep to tap into the saline aquifers. Saltmakers soon switched from wood to coal to fuel the fires that kept the kettles boiling, and organized the Kanawha Salt Company to monopolize production and control prices. The Kanawha salt industry boomed until a major flood in 1861, followed by the Civil War, disrupted production and altered state boundaries so the site was no longer in Virginia. Kanawha brines are still extracted from wells 350 feet deep, crystallized by solar drying in hothouses, and sold to food connoisseurs who seek an artisan salt.12
the salt licks and salt springs on the Kanawha River were developed into a industrial complex, using wood and then coal to fuel the fires that extracted the mineral resource
Source: Historical collections of Virginia, View of the Salt-Works on the Kanawha (p.345)
The salt resources on the North Fork of the Holston River formed over 300 million years ago when seawater evaporated in a basin with tidal flats, in an area similar to today's Persian Gulf or the Gulf of California. Salt water was intermittently trapped in the basin, now the location of the town of Saltville. As water evaporated, minerals in the seawater were concentrated until they were precipitated in layers of salt as "evaporite deposits." The largest deposits were of sodium chloride (NaCl) and gypsum/calcium carbonate (CaSO4·2H2O).
New inflows created a repeating cycle that produced thick beds later named the Little Valley and the Maccrady Shale formations, formed during what geologists label the Mississippian subperiod of the Carboniferous Period. The ocean later covered the evaporite deposits, sealing them underground. Various layers of limestone, shale, and other rocks ended up on top.
Folding and fracturing during initial deposition was followed by intense deformation during the later Alleghenian orogeny. Tectonic pressures caused the rock layers to break and created the Saltville fault. That scrambled the underground layers of evaporite deposits until the once-horizontal beds of salt ended up in fragmented pods and stringers. Thrust faults also moved the bedrock around 20 miles. Roughly 280 million years ago, the deposits underneath Saltville would have been located in what is now North Carolina, and the continental plate was located near the equator.13
Since at least the Ice Age, groundwater circulating through those deposits has emerged at the surface in springs. The groundwater reaching the surface was enriched in salt, and the naturally-occurring brine has attracted animals to salt licks. Paleontology excavations have exposed remains of mastodons, woolly mammoths, and other Pleistocene Epoch animals. The collection and display of fossils from Saltville dates back to the time of Thomas Jefferson.
Colonists began to settle in the area in the 1730's. They needed salt to preserve beef, pork, and venison, and to pickle vegetables for long-term storage. Hauling salt upstream from Chesapeake Bay port cities, across the mountains on roads barely fit for wagons, was always very expensive.
During the American Revolution, Virginia's salt imports from overseas and the Caribbean were cut off by naval blockades. Coastal plain residents could cope with this hardship, especially by using slave labor to make salt from seawater. Across the Blue Ridge and away from the Kanawha River saline springs, salt was expensive and occasionally hard to acquire at any price.
In the 1780's, the Campbells, Kings, and other early industrialists started digging shallow wells into the Maccrady Shale to extracted the brine. It was evaporated in kettles to produce salt for preserving meat and other food. During the Civil War, Union forces raided Saltville to destroy the furnaces and salt-boiling kettles. Blocking salt production would limit the Confederacy's ability to transport salted beef in barrels, constraining the ability of large groups of Confederate soldiers to march away from supply bases in order to fight Union armies.
operations at Saltville before and after the Civil War involved boiling brine to precipate salt
Source: Harper's Weekly, Interior View Of The Salt-Works (January 14, 1865); University of North Carolina, The Great South; A Record of Journeys in Louisiana, Texas, the Indian Territory, Missouri, Arkansas, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, Kentucky, Tennessee, Virginia, West Virginia, and Maryland (1875)
In the 1890's, Mathieson Alkali Works started operations and the town of Saltville was chartered in Smyth County. Deeper wells pumped more brine to the surface, where it was processed to create chlorine, bicarbonate of soda, and caustic soda chemicals for various industrial uses (instead of boiled down to produce "table salt" for use as a preservative). Gypsum, used for plaster and modern drywall, was mined at Plasterco in Washington County.
Waste residue from the saltmaking was collected behind a "muck dam" constructed in 1908 on the North Fork of the Holston River. That dam broke in 1924, and accumulated alkali waste flooded the community of Palmerton just downstream. At least 19 people died. The river was so polluted by the waste that residents of Kingsport Tennessee, more than 50 miles downstream, found it easy to collect fish that were unable to breathe in the water.14
Communities downstream of Saltville that used the North Fork of the Holston River as a water supply source has to spend extra money in the treatment of drinking water to remove chlorides dumped by the chemical plant, to "soften" the hard water. At the start of the 1970's, Olin (the successor to Mathieson Alkali Works) was discharging wastewater into the river with 4,000ppm salt, far exceeding the Commonwealth of Virginia's water quality standard of 500ppm.15
alkali pollution from the plant at Saltville contaminated water downstream into Tennessee and triggered complaints from Kingsport until Olin closed the facility in 1972, but mercury trapped in the sediments will continue to contaminate the water and accumulate in fish tissue for many decades to come
Source: ESRI, ArcGIS Online
Saltville developed as a company town. Much of the housing was owned by Olin, and it funded many of the community services that in other towns were the responsibility of taxpayers, churches, or charitable organizations.
In 1972, the Olin shut down its operations at Saltville rather than rehabilitate the outdated equipment and comply with water quality standards established by the Virginia Water Control Board and the new Environmental Protection Agency. Olin's closure had a dramatic effect on local employment in Smyth County, which had a population below 32,000 people:16
The chemical plant became a Superfund site requiring extensive cleanup, due to pollution caused by mercury used in the chlorine production process.
Today, salt production in Virginia is a byproduct. The old mining operations in Saltville created voids in the underground salt beds as brine was pumped to the surface. Starting in the 1990's, more water was pumped underground to create ever greater "empty space" between the remaining grains of salt to create a natural gas storage cavern.
During the summer when demand for natural gas is low, a surplus of gas is transported to Saltville by pipeline from the Gulf of Mexico, nearby coalbed methane wells, and new "fracked" wells drilled horizontally into shale formations. That gas is injected into the ground at Saltville, where it displaces brine and is stored until the cold winter months. When demand increases and the pipeline bringing more gas from the Gulf Coast to Saltville is at capacity, gas is pumped out of the artificial reservoir and sold to customers in the region and further north.
Developing and maintaining the reservoir, with its valuable empty space, requires pumping brine to the surface. THe brine was a waste product, and expensive to treat in order to comply with water quality standards. Starting in 2000, the gas storage company began to process the saline water and sell the salt products for agricultural operations in the region.17
Saltville developed as a major industrial site prior to the Civil War
Source: Library of Congress, A map of the state of Virginia, constructed in conformity to law from the late surveys authorized by the legislature and other original and authentic documents (1859)
1. Ian W. Brown, "The Role of Salt in Eastern North American Prehistory," May 1981, http://www.crt.state.la.us/dataprojects/archaeology/virtualbooks/SALT/hist.htm (last checked April 16, 2017)
2. Carroll E. Smith, Pioneer Times in the Onondaga Country, 1904, p.109, https://archive.org/details/pioneertimesino00smitgoog; Jeffrey P. Brain, Bill Day, "On the Tunica Trail," Louisiana Archaeological Survey and Antiquities Commission, 1994, http://www.crt.state.la.us/dataprojects/archaeology/virtualbooks/TUNICA/tunica.htm; John Ingles, "The Narrative of Col. John Ingles Relating to Mary Ingles and the Escape from Big Bone Lick," 1824, posted online by Boone County Public Library, http://bcplfusion.bcpl.org/Repository/MI_MS_trans.pdf (last checked July 5, 2014)
3. Silvester Jourdain, "Discovery of the Bermudas," in Louis B. Wright (editor), A Voyage to Virginia in 1609: Two Narratives: Strachey's "True Reportory" and Jourdain's Discovery of the Bermudas, University of Virginia Press, 2013, pp.114-115, http://www.jstor.org/stable/j.ctt7zwcz5 (last checked April 6, 2016)
4. Online Etymology Dictionary, http://www.etymonline.com/index.php?search=salary; "The Salt Works," National Park Service, Lewis and Clark National Historic Park, http://www.nps.gov/lewi/planyourvisit/saltworks.htm (last checked July 5, 2014)
5. "They really drank this stuff?," Ideation, William and Mary College, October 17, 2011, https://www.wm.edu/research/ideation/social-sciences/they-really-drank-this-stuff6752.php (last checked July 15, 2015)
6. Jennings Cropper Wise, Ye Kingdome Of Accawmacke Or The Eastern Shore Of Virginia In The Seventeenth Century, The Bell Book And Stationery Co., Richmond, Virginia, 1911, pp.21-25, https://archive.org/details/yekingdomeofacca00wise; Nora Miller Turman, The Eastern Shore of Virginia, 1603-1964, The Eastern Shore News, Onancock (Virginia), 1964, pp.5-6, https://archive.org/details/easternshoreofvi00turm; Charles E. Hatch, The First Seventeen Years: Virginia 1607-1624, University Press of Virginia, 1957, p.1, https://archive.org/details/thefirstseventee30780gut (last checked June 28, 2014)
7. Jennings Cropper Wise, Ye Kingdome Of Accawmacke Or The Eastern Shore Of Virginia In The Seventeenth Century, pp.304-306, (last checked June 26, 2014)
8. Larry G. Bowman, "The Scarcity of Salt in Virginia during the American Revolution," The Virginia Magazine of History and Biography, irginia Historical Society, Vol. 77, No. 4 (October 1969), pp. 465-472, http://www.jstor.org/stable/4247510 (last checked July 5, 2014)
9. "Batts and Fallam Expedition of 1671," West Virginia Archives and History, http://www.wvculture.org/history/settlement/battsandfallam01.html (last checked July 5, 2014)
10. Thomas Walker, "Doctor Thomas Walker's Journal (6 Mar 1749/50 - 13 Jul 1750), A Record of His Travels in Present-day Virginia, Tennessee and Kentucky, 1750, http://www.tngenweb.org/tnland/squabble/walker.html (last checked July 5, 2014)
11. Thomas Jefferson, "Query VI," Notes on the State of Virginia, (last checked June 26, 2014), from "Documenting the American South," University of North Carolina, http://docsouth.unc.edu/southlit/jefferson/jefferson.html
12. "History of West Virginia Mineral Industries - Salt," West Virginia Geological and Economic Survey, July 19, 2004, http://www.wvgs.wvnet.edu/www/geology/geoldvsa.htm; "Fine Brine From Appalachia: The Fancy Mountain Salt That Chefs Prize," National Public Radio, November 26, 2015, http://www.npr.org/sections/thesalt/2015/11/25/457371557/fine-brine-from-appalachia-the-fancy-mountain-salt-that-chefs-prize (last checked November 27, 2015)
13. Robert C. Whisonant, "Geology and the Civil War in Southwestern Virginia: The Smyth County Salt Works," Virginia Minierals, Virginia Department of Mines, Minerals and Energy, August 1996, pp.22-24, http://www.dmme.virginia.gov/commercedocs/VAMIN_VOL42_NO03.pdf; Charles S. Bartlett, "Developmental History and Subsidence Resulting From Salt Extraction at Saltville, Virginia," in K. S. Johnson and J. T. Neal (editors), Evaporite Karst and Engineering/Environmental Problems in the United States, Oklahoma Geological Survey Circular 109, p.338, http://www.ogs.ou.edu/pubsscanned/Circulars/circular109.pdf (last checked June 26, 2014)
14. "The Muck Dam Disaster: Christmas 1924," The Mountain Laurel< December, 1988, http://www.mtnlaurel.com/history/1506-the-muck-dam-disaster-christmas-1924.html (last checked July 14, 2015)
15. Kimberly Barr Byrd, Debra J. Williams, Smyth County, Arcadia Publishing, 2005, p.96, https://books.google.com/books?id=EkpYozzuKnQC (last checked July 14, 2015)
16. Jeffrey C. Weaver, Saltville, Arcadia Publishing, 2006, p.33, https://books.google.com/books?id=wigzzrz0e_YC; "Saltville helped turn abandoned caverns into much-needed jobs," Virginia Town & City, Virginia Municipal League, September 2003, http://transformgov.org/en/knowledge_network/documents/kn/document/4631/saltville_helped_turn_abandoned_caverns_into_muchneeded_jobs; "A Company Town Hangs On After The Company Is Gone," Washington Post, August 6, 1994, http://www.washingtonpost.com/archive/local/1994/08/06/a-company-town-hangs-on-after-the-company-is-gone/9364b039-a3b3-4be2-b20b-ee1417f8b6b2/; "Census of Population and Housing - Virginia, 1970," Bureau of Census, https://www.census.gov/prod/www/decennial.html (last checked July 14, 2015)
17. Amy K. Gilmer, Catherine B. Enomoto, James A. Lovett, David B. Spears, "Mineral And Fossil Fuel Production In Virginia (1999-2003)," Virginia Department of Mines, Minerals and Energy, Open-File Report 05-04, pp.18-20, https://www.dmme.virginia.gov/dgmr/pdf/VDMR_OF_05_04.pdf; "Saltville Gas Storage," SpectraEnergy, http://www.spectraenergy.com/Operations/Storage/Saltville-Gas-Storage/ (last checked July 14, 2015)