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38-535: A thermal generating station, Coleson Cove is situated on a cove of the same name, along the shore of the Bay of Fundy 16 km (9.9 mi) southwest of the mouth of the Saint John River at the city's central core. The generating station is owned and operated by New Brunswick Power Coleson Cove Corporation ( Colesonco ), a wholly owned subsidiary of New Brunswick Power Generation Corporation (Genco), which

76-556: A hydration product of anhydrite . The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison . Fine-grained white or lightly tinted forms of gypsum known as alabaster have been used for sculpture by many cultures including Ancient Egypt , Mesopotamia , Ancient Rome , the Byzantine Empire , and the Nottingham alabasters of Medieval England . The word gypsum

114-720: A $ 2.2 billion lawsuit that was filed simultaneously with the United States District Court for the Southern District of New York in Manhattan and the Court of Queen's Bench of New Brunswick in Fredericton during the last week of February, naming both PDVSA and its United States subsidiary Bitumenes Orinoco S.A. (Bitor) as defendants and citing the companies' inability to negotiate and sign

152-464: A (then) future supply of fuel valued at $ 218m. On 23 August 2007, the Energy and Utilities Board (EUB) approved a regulatory deferral for the purpose of returning the benefit of the lawsuit settlement with PDVSA to customers in a levelised manner. The deferral will be allocated over a period of 17 years in order to best match the benefit from the settlement to the customers that the customers will pay for

190-424: A circular bay with a narrow entrance, called a cove . Another way is that waves can transport rocks and sediment towards cliffs or rock faces, which helps erode softer rock and gradually form coves due to friction. Additionally, rivers or streams that flow into the sea can contribute to creating natural harbors. "Over time, the sediment carried by the flow of the water will help erode any soft, rocky areas," leading to

228-495: A contract to deliver orimulsion to Coleson Cove. On March 16, 2004 PDVSA announced that it was phasing out all orimulsion production; since NB Power's Dalhousie Generating Station 's fuel supply agreement ends in 2010, it is assumed that both plants will be forced to switch to an alternative. The failure to secure a fuel supply agreement with PDVSA for the Coleson Cove Generating Station overshadowed

266-522: A corner, nook, or cranny, either in a river, road, or wall, especially where the wall meets the floor. An example is Lulworth Cove on the Jurassic Coast in Dorset , England. To its west, a second cove, Stair Hole , is forming. Coves are formed by differential erosion , which occurs when softer rocks are worn away faster than the harder rocks surrounding them. These rocks further erode to form

304-409: A larger bay . Small, narrow, sheltered bays, inlets, creeks , or recesses in a coast are often considered coves. Colloquially, the term can be used to describe a sheltered bay. Geomorphology describes coves as precipitously walled and rounded cirque -like openings like a valley extending into or down a mountainside, or in a hollow or nook of a cliff or steep mountainside. A cove can also refer to

342-474: A range of industrial processes. Flue gas desulfurization gypsum (FGDG) is recovered at some coal-fired power plants. The main contaminants are Mg, K, Cl, F, B, Al, Fe, Si, and Se. They come both from the limestone used in desulfurization and from the coal burned. This product is pure enough to replace natural gypsum in a wide variety of fields including drywalls, water treatment, and cement set retarder. Improvements in flue gas desulfurization have greatly reduced

380-413: A result, waste gypsum is stored in stacks indefinitely, with significant risk of leaching their contaminants into water and soil. To reduce the accumulation and ultimately clear out these stacks, research is underway to find more applications for such waste products. People can be exposed to gypsum in the workplace by breathing it in, skin contact, and eye contact. Calcium sulfate per se is nontoxic and

418-478: A source of sulfur for plant growth, and in the early 19th century, it was regarded as an almost miraculous fertilizer. American farmers were so anxious to acquire it that a lively smuggling trade with Nova Scotia evolved, resulting in the so-called "Plaster War" of 1820. Gypsum is moderately water-soluble (~2.0–2.5 g/L at 25 °C) and, in contrast to most other salts, it exhibits retrograde solubility, becoming less soluble at higher temperatures. When gypsum

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456-543: A wide range of colors to local deposits. Because gypsum dissolves over time in water, gypsum is rarely found in the form of sand. However, the unique conditions of the White Sands National Park in the US state of New Mexico have created a 710 km (270 sq mi) expanse of white gypsum sand, enough to supply the US construction industry with drywall for 1,000 years. Commercial exploitation of

494-510: Is contaminated by impurities found in the rock, namely fluoride , silica , radioactive elements such as radium , and heavy metal elements such as cadmium . Similarly, production of titanium dioxide produces titanium gypsum (TG) due to neutralization of excess acid with lime . The product is contaminated with silica, fluorides, organic matters, and alkalis. Impurities in refinery gypsum waste have, in many cases, prevented them from being used as normal gypsum in fields such as construction. As

532-588: Is derived from the Greek word γύψος ( gypsos ), "plaster". Because the quarries of the Montmartre district of Paris have long furnished burnt gypsum ( calcined gypsum) used for various purposes, this dehydrated gypsum became known as plaster of Paris . Upon adding water, after a few dozen minutes, plaster of Paris becomes regular gypsum (dihydrate) again, causing the material to harden or "set" in ways that are useful for casting and construction. Gypsum

570-448: Is even approved as a food additive, but as powdered gypsum, it can irritate skin and mucous membranes. The Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for gypsum exposure in the workplace as TWA 15 mg/m for total exposure and TWA 5 mg/m for respiratory exposure over an eight-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set

608-593: Is heated in air it loses water and converts first to calcium sulfate hemihydrate ( bassanite , often simply called "plaster") and, if heated further, to anhydrous calcium sulfate ( anhydrite ). As with anhydrite , the solubility of gypsum in saline solutions and in brines is also strongly dependent on sodium chloride (common table salt) concentration. The structure of gypsum consists of layers of calcium (Ca ) and sulfate ( SO 2− 4 ) ions tightly bound together. These layers are bonded by sheets of anion water molecules via weaker hydrogen bonding , which gives

646-428: Is itself a wholly owned subsidiary of provincial Crown corporation NB Power . Coleson Cove opened in 1976 and was designed to burn #6 fuel oil , also known colloquially as "bunker C". Fuel is delivered via the 20 km (12 mi) underground Lorneville Pipeline , which runs from Irving Oil 's Canaport bulk oil tanker unloading station off Red Head, 4 km southeast of the city's central core, crossing to

684-462: Is prized for ornamental work of various sorts. In arid areas, gypsum can occur in a flower-like form, typically opaque, with embedded sand grains called desert rose . It also forms some of the largest crystals found in nature, up to 12 m (39 ft) long, in the form of selenite. Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks . Deposits are known to occur in strata from as far back as

722-498: The Archaean eon . Gypsum is deposited from lake and sea water, as well as in hot springs , from volcanic vapors, and sulfate solutions in veins . Hydrothermal anhydrite in veins is commonly hydrated to gypsum by groundwater in near-surface exposures. It is often associated with the minerals halite and sulfur . Gypsum is the most common sulfate mineral. Pure gypsum is white, but other substances found as impurities may give

760-790: The Mars Reconnaissance Orbiter (MRO) have indicated the existence of gypsum dunes in the northern polar region of Mars, which were later confirmed at ground level by the Mars Exploration Rover (MER) Opportunity . Commercial quantities of gypsum are found in the cities of Araripina and Grajaú in Brazil; in Pakistan, Jamaica, Iran (world's second largest producer), Thailand, Spain (the main producer in Europe), Germany, Italy, England, Ireland, Canada and

798-508: The Clean Energy Coalition of New Brunswick as the largest single point source of air pollution and greenhouse gases in the region. Emissions from the station in the form of particulates have been, and remain, a frequent source of pollution complaints in the region. In May 2011 NB Power announced that it was considering converting Coleson Cove to burn natural gas . The high price of fuel oil in recent years, coupled with

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836-524: The Coleson Cove Generating Station Refurbishment. Forced to continue its reliance upon heavy fuel oil, NB Power realized several environmental benefits and plant efficiencies resulting from the refurbishment as the generating station moved ahead 2 generations from its original polluting 1970s technology: SO 2 emissions were reduced by 77%, NO x emissions were reduced by 70% and particulate release

874-700: The United States. Large open pit quarries are located in many places including Fort Dodge, Iowa , which sits on one of the largest deposits of gypsum in the world, and Plaster City, California , United States, and East Kutai , Kalimantan , Indonesia. Several small mines also exist in places such as Kalannie in Western Australia , where gypsum is sold to private buyers for additions of calcium and sulfur as well as reduction of aluminum toxicities on soil for agricultural purposes. Crystals of gypsum up to 11 m (36 ft) long have been found in

912-478: The addition of six flue gas desulphurization (FGD) scrubbers which were designed to also remove hydrochloric acid . Political instability in Venezuela in 2003 is believed to have contributed to PDVSA balking at formally signing a contract to implement an orimulsion deal with NB Power for Coleson Cove. By winter 2004 it was apparent that the fuel supply agreement with PDVSA had fallen through and NB Power launched

950-495: The amount of toxic elements present. Gypsum precipitates onto brackish water membranes , a phenomenon known as mineral salt scaling , such as during brackish water desalination of water with high concentrations of calcium and sulfate . Scaling decreases membrane life and productivity. This is one of the main obstacles in brackish water membrane desalination processes, such as reverse osmosis or nanofiltration . Other forms of scaling, such as calcite scaling, depending on

988-418: The area, strongly opposed by area residents, was permanently prevented in 1933 when President Herbert Hoover declared the gypsum dunes a protected national monument . Gypsum is also formed as a by-product of sulfide oxidation , amongst others by pyrite oxidation , when the sulfuric acid generated reacts with calcium carbonate . Its presence indicates oxidizing conditions. Under reducing conditions,

1026-489: The caves of the Naica Mine of Chihuahua , Mexico. The crystals thrived in the cave's extremely rare and stable natural environment. Temperatures stayed at 58 °C (136 °F), and the cave was filled with mineral-rich water that drove the crystals' growth. The largest of those crystals weighs 55 tonnes (61 short tons) and is around 500,000 years old. Synthetic gypsum is produced as a waste product or by-product in

1064-711: The city's west side via the Reversing Falls Railway Bridge . The #6 fuel oil is stored in two 1.5 million barrel tanks at Canaport and four 300,000 barrel tanks at Coleson Cove. The plant features three boiler units powering three 350 MW generators for a total output of 1,050 MW, which is approximately 33% of the utility's generating capacity. To achieve this, Coleson Cove burns 5 million barrels of oil annually and discharges its exhaust through twin 183 m (600 ft) smoke stacks. In late 2001, NB Power announced its intention to refurbish Coleson Cove and convert its fuel source to orimulsion , which

1102-672: The crystal perfect cleavage along the sheets (in the {010} plane). Gypsum occurs in nature as flattened and often twinned crystals , and transparent, cleavable masses called selenite . Selenite contains no significant selenium ; rather, both substances were named for the ancient Greek word for the Moon . Selenite may also occur in a silky, fibrous form, in which case it is commonly called "satin spar". Finally, it may also be granular or quite compact. In hand-sized samples, it can be anywhere from transparent to opaque. A very fine-grained white or lightly tinted variety of gypsum, called alabaster ,

1140-478: The final term of Premier Bernard Lord and is believed to have played a role in his government's subsequent 2006 electoral defeat, since the publicly owned utility's write-down of the loss added substantially to the provincial long-term debt. On 3 August 2007, the NB Power Group settled the lawsuit with PDVSA over the failed contract for a total book value of $ 333m, split between a cash payment of $ 115m and

1178-550: The formation of a cove. This article related to topography is a stub . You can help Misplaced Pages by expanding it . Gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate , with the chemical formula CaSO 4 ·2H 2 O . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster , drywall and blackboard or sidewalk chalk . Gypsum also crystallizes as translucent crystals of selenite . It forms as an evaporite mineral and as

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1216-476: The plant's still-high emissions, has meant that it has sat idle for much of the last decade as it has been cheaper for NB Power to purchase imported electricity to replace the generating capacity. The decline in natural gas prices in recent years, increased cost of the mid-life refurbishment of the nearby Point Lepreau Nuclear Generating Station , and the rising cost of replacement imported electricity has provided an economic case for converting Coleson Cove, however,

1254-702: The project must be approved by the Government of New Brunswick and undergo environmental study. Additionally, a natural gas pipeline to supply the plant must be constructed from either the Saint John Lateral of the Maritimes & Northeast Pipeline or the Brunswick Pipeline . Cove A cove is a small bay or coastal inlet . They usually have narrow, restricted entrances, are often circular or oval, and are often situated within

1292-451: The sulfates it contains can be reduced back to sulfide by sulfate-reducing bacteria . This can lead to accumulation of elemental sulfur in oil-bearing formations, such as salt domes, where it can be mined using the Frasch process Electric power stations burning coal with flue gas desulfurization produce large quantities of gypsum as a byproduct from the scrubbers. Orbital pictures from

1330-561: The water source, can also be important considerations in distillation , as well as in heat exchangers , where either the salt solubility or concentration can change rapidly. A new study has suggested that the formation of gypsum starts as tiny crystals of a mineral called bassanite (2CaSO 4 ·H 2 O). This process occurs via a three-stage pathway: The production of phosphate fertilizers requires breaking down calcium-containing phosphate rock with acid, producing calcium sulfate waste known as phosphogypsum (PG). This form of gypsum

1368-524: Was known in Old English as spærstān , "spear stone", referring to its crystalline projections. Thus, the word spar in mineralogy, by comparison to gypsum, refers to any non- ore mineral or crystal that forms in spearlike projections. In the mid-18th century, the German clergyman and agriculturalist Johann Friderich Mayer investigated and publicized gypsum's use as a fertilizer. Gypsum may act as

1406-596: Was reduced by 75%. In addition, the changes in the burners and addition of scrubbers saw the production of a gypsum byproduct which was commercially resold for wallboard through a subsidiary of J.D. Irving Limited . Despite the improvements reducing emissions, the Coleson Cove Generating Station remains the largest thermal generating station in Atlantic Canada and has been cited by the New Brunswick Environmental Network and

1444-519: Was sole-sourced from Petróleos de Venezuela S.A. (PDVSA) in a $ 2 billion 20-year supply agreement. The $ 2.2 billion refurbishment project involved reconfiguring the boilers, as well as on-land storage tanks, Lorneville Pipeline, and some equipment at Irving Oil's Canaport unloading facility. The project was envisioned to be complete in November 2004 with a cost of $ 818 million. Part of this refurbishment saw Coleson Cove fitted with LO-NOx burners and

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