Description: Havelock is a rural village about 14 to 15 km northwest of Petitcodiac in Kings County, near its eastern boundary with Westmorland County. Limestone resources in the Havelock area are of special interest because it is the only deposit in New Brunswick that has been utilized as raw material for cement, calcined lime (quick and hydrated lime), agricultural lime and aggregate materials. Several quarries have been operated in the region at one time or another. The extensive deposit of limestone from area were first reported by Gesner in 1841 (Gesner 1841, p.30). In 1965, Hamilton (1965, p. 71) described the limestone resource as belonging to the Windsor Group, exposed in three prominent southwest trending ridges: the Springhill, Samphill and Butternut Ridges forming the Havelock Syncline (Basin), underlying an area exceeding 40 square kilometres. Limestone has been quarried from these resources for almost 70 years (1939) and at present (2008), two quarries, the Samphill and McGee quarries are active in the area. These quarries, operated by Graymont (NB) Ltd (formerly Havelock Lime) serve as a source of agricultural limestone, chemical lime, general construction stone and related limestone products. The limestone quarried is typically of the massive, high calcium type with shaly and flaggy interbeds occurring at the bottom and at the top of the formation. A mass of dolomite (high-magnesium limestone varying from < a metre to 30 m across, and 18 m thick, is found near the western end of a quarry at Samphill. This represents one of the few locations in New Brunswick where dolomite is found in Windsor strata.
Geology
The limestone resource in the Havelock area belong to the Early Carboniferous (Visean) Windsor Group. These rocks typically consist of olive-grey, reddish grey and dark grey limestone, and minor dolomite of the Gays River Formation. The Gays River here conformably overlies reddish grey, coarse-grained sandstone and conglomerate of the Hillsborough Formation and is overlain by fine-grained sandstone and siltstone of the Mabou Group. The Gays River-Mabou contact is gradational, characterized by a sequence of interbedded bituminous limestone, fine-grained sandstone and dark greenish grey mudstone collectively referred to as the "Samphill beds" by McCutcheon (1981). These rocks may be equivalent to those of the Clover Hill Formation in the Sussex area, 35 km to the south.
In the Havelock area Gays River limestone is restricted to a series of northeast-trending fault blocks superimposed on two regional synclinal structures, the Havelock and Springhill-Hicksville synclines, which collectively form the "Havelock basin". Although the basin extends over a considerable area, limestone exposures within it are limited, to northeast-trending ridges. The veneer of glacial till that directly overlies the limestone throughout much of the area seldom exceeds a thickness of 3 m on ridge-crests. Greater thicknesses of till, as well as scattered sand and gravel deposits, occur in intervening valley areas, particularly in the valley of Ridge Brook, which forms the main drainage system in the region.
Detailed mapping and related laboratory and petrographic and field investigations of the Gays River limestone in the basin (McCutcheon 1981; Noble and Webb 1982) have resulted in the establishment of four distinctive limestone lithofacies. These are represented by algal bafflestone, massive and thinly bedded algal boundstones, and thinly bedded wackestones and packstones comprising a maximum collective thickness of 30 m. These lithofacies are described in detail by Noble and Webb (1982).
Gays River limestone is overlain by a sequence of yellowish brown to brownish black, very thinly to thinly bedded, siliciclastic wackestone (algal, in part), dark greyish green mudstone and sandstone up to 8 m thick. These rocks, referred to as the "Samphill beds" (McCutcheon 1981), form a transitional zone between the dominantly marine Gays River limestone and the overlying yellowish green, grey-green to reddish brown, fluvial sandstones and mudstones of the Mabou Group. This transitional zone which may be equivalent to the Clover Hill Formation of the Sussex area can best be seen immediately north of the a former cement plant a few kilometres east of Havelock and along the south quarry wall at the quarry at Samphill.
The Havelock area, Gays River limestone occupy the troughs of the two northeast-trending synclines. The largest, the Havelock Syncline, extends for a strike length of about 12 km and has a maximum width of approximately 2 km. Immediately to the north of this structure, the smaller Springhill- Hicksville Syncline also contains thin erosional remnants of Gays River limestone. The flanks of these synclinal structures seldom exceed dips of 20 degrees, except locally, where faulting has resulted in increasing dips that may exceed 50 degrees. Although the exact location and lateral extent of these faults are speculative, trends of topographic irregularities and the results of limited drilling in several areas indicate the existence of at least four in the Havelock area: two in the northern half of the Havelock Syncline and two in the southern part of the Springhill-Hicksville Syncline. Vertical displacements probably do not exceed 15 m. All faults trend to the northeast conforming to the overall structural fabric of the region. The origin of these faults is unknown, although it is thought that they may have developed as a means of relieving stress caused by post-Windsor basin-fill sedimentation or as a consequence of a more regional tectonic event.
The thickness of Gays River limestone in the Havelock area is variable, and partly depends on the following: 1) the paleotopography of the basin floor at the time of deposition and /or 2) syn- and/or post depositional structural modifications to the original basin (i.e. faulting, folding) and the geographic location with respect to major structural features (i.e. deposits thicken toward synclinal axes).
As a result, limestone thicknesses can vary from 3 m to slightly more than 30 m throughout the area. Extensive drilling in the eastern half of the Havelock Syncline, south of its central axis, indicates an average thickness of 18 to 20 m, a reasonable estimate for most of the limestone at this location. In the western half, all but two narrow bands of the limestone on the northern and southern flanks are blanketed by fine-grained Hopewell clastics. On the southern flank, limestone up to 9 m thick underlies a narrow ridge extending from the Havelock Village limits, southwest to Lower Ridge. Limestone up to 30 m thick underlies a pronounced ridge on the northern flank of the syncline, west of the intersection of Cross and Mineral Springs roads at Symphile. Limestone with a maximum thickness of 15 m has been intersected in the western half of the Springhill-Hicksville Syncline at Springhill, north of the Havelock Syncline.
Exploration and Development
Exploration and small-scale development of the Havelock limestone deposits dates back to the late 1700s, shortly after the arrival of the first Loyalist settlers. The ruins of primitive kilns throughout the area, attest to the existence of these early enterprises. A report by Goudge (1934) contains one of the earliest records of exploration for limestone in the area. Goudge reported that the Canada Cement Company of Montreal had been exploring for cement-grade limestone "along the summit of a low, broad ridge, known as the Butternut Ridge," just east of the village of Havelock. Although reference was made to core drilling, the location and number of holes drilled were not reported. Most are assumed to have been in the vicinity of the former No. 1 quarry of Lafarge Canada Inc., located south of Highway# 880 near its intersection with the Beckwith Road.
Prior to the interest shown by the Canada Cement Company, a limited amount of limestone was being quarried at Springhill, supplying local farmers with agricultural lime. In 1938, the small Springhill aglime business was purchased by Mr. Roy Alward. Because the demand for agricultural lime was steadily increasing, Mr. Alward moved the operation to Havelock in 1944, a location closer to the railway. A larger crushing facility, operating under the name Havelock Lime Works, was constructed to accommodate expanding markets in New Brunswick and Prince Edward Island.
In the early 1950s Canada Cement Company also saw an opportunity to expand its cement market in Atlantic Canada and abroad. In 1952, a quarry and production facility was established near Butternut Ridge, 1.5 km east of the Havelock Lime Works operation. Between 1957 and 1960, the company embarked on an extensive drilling program to assist in adding to its proven reserves near the plant site.
By the early 1960s, Havelock Lime Works was producing agricultural lime and road aggregate, and eventually expanded into the manufacturing of high calcium poultry grits, fertilizer filler, concrete aggregate, and high calcium lime for the pulp and paper industry. In 1964, Havelock Lime Works was incorporated, becoming Havelock Lime Works Ltd.
Very little exploration took place within the Havelock Basin during the first half of the 1960s. In 1965, Dominion Lime Co. undertook a program of reconnaissance mapping, surface sampling, and drilling to determine areas of high calcium limestone of sufficient grade and size to support a lime plant. A number of holes were drilled northeast of the village in the Upper Ridge area, however the company's limestone specifications could not be met at this location and the mineral rights were relinquished. The prospect was subsequently picked up by Canada Cement Lafarge Ltd.
Canada Cement re-established an aggressive limestone exploration program in 1965, primarily in the western half of the Havelock Basin. A total of 32 drill holes, distributed among 90 mining claims, were completed in areas of limited exposure. Only the claims over the Springhill deposits were retained; later they were converted to a mining license.
To keep pace with the increasing demand for agricultural and high calcium lime in the Maritime Provinces, Havelock Lime Works Ltd. began construction of a more efficient lime reduction plant in the late 1960s. Developing lime markets in the pulp and paper, mining, and chemical industries and in the field of pollution control soon presented itself as an opportunity to expand into the manufacture of quick and hydrated lime. Adequate reserves of high calcium limestone were required to justify the construction of a kiln. The company undertook an extensive drilling program just north of Havelock and within 1 km of the existing plant in the village. Results from 21 holes indicated that the quality of stone was far below required specifications, so the search for reserves shifted to the Samphill area, about 6 km southwest of the existing plant where preliminary surface sampling exhibited a more favourable locale for high calcium limestone deposits. Seven drill holes confirmed grade continuity and indicated that a substantial tonnage of suitable stone was readily available at the Symphile location. On the basis of the drilling results and optimistic market forecasts for quick and hydrated lime, an 80 000 ton/year lime kiln was constructed adjacent to the existing plant. It commenced operation in 1970. A subsidiary company, Havelock Processing Ltd., was formed to manage the new venture.
By 1974, approximately a million tons of limestone had been removed from the Samphill area and reserves outlined in 1965, were approaching exhaustion. The reserve shortage prompted the company to drill nine more holes in an area to the west of the main quarry in 1975. Although an additional 2,500,000 tons of high calcium limestone was confirmed, quarry expansion into this area was hampered by deposits of dolomite which affected grade control and the thick overburden encountered which would inflate quarrying costs. To more thoroughly assess additional limestone reserves in the Havelock Basin, the New Brunswick Department of Natural Resources conducted a compilation and reassessment of the available geological information in 1975. Havelock Lime Works Ltd. also conducted a limited drilling program near Hicksville in 1975 and a more detailed evaluation of limestone in the Upper Ridge-Beckwith Road area in 1976. Preliminary results at Hicksville were not encouraging; however, 14 holes drilled in the Upper Ridge area immediately north of Highway 880 proved sufficient reserves of chemically acceptable kiln-feed grade (>53% CaO) material.
The Canadian Nickel Co. also became active in the Havelock area in 1976, conducting geophysical and geochemical surveys over a two year period. In 1978 three holes were drilled southwest of the village to test uranium anomalies. Drilling results were not encouraging and the company dropped its claims.
After 1976, exploration within the Havelock basin was mainly associated with expansion at the Canada Cement Lafarge Ltd.'s No. 2 quarry, which had opened in the mid-1960s. In 1981, the company began a program to drill 32 holes adjacent to the No. 2 quarry and to the east and west of the existing plant to quantify limestone reserves in these areas. An additional 13 holes were put down in the Springhill area that year as well. Although significant limestone reserves were indicated subsequent work involving geophysical surveys and additional drilling was undertaken to refine the geological boundaries of the deposit.
Beginning in 1983, depressed cement market conditions forced Lafarge to temporarily scale down its cement operation. Subsequently the cement plant continued to function primarily on a demand basis until it was shut down permanently in 1987. Eventually company became a supplier of crushed stone aggregate to a subsidiary company, Lafarge Construction Materials and supplied Havelock Lime with limestone from a new quarry (McGee Quarry) that opened in 1986, less than a kilometre east of the former cement plant.
In 1983, Dickenson Mines Ltd. purchased 60% of the assets of the Havelock Lime group of companies as part of a planned diversification and expansion program. The remaining assets of the group were purchased by Dickenson four years later. three years later (1986), Dickenson announced plans to construct a Fuller-Beckenbach annular-shaft kiln (Webb 1994) adjacent to the existing 200 tonne per day rotary kiln. The new structure, completed in 1989 was the first of its kind in North America. The new kiln increased the company's lime production capacity to 300 tonnes per day with lower fuel consumption resulting in significant savings in operational cost expenses. Following corporate restructuring in 1989, Dickenson Mines assets were combined with those of several other related companies to form the new Goldcorp Inc. of which Havelock Lime became a division.
Since Dickenson's and subsequently Goldcorps purchase of Havelock's assets, several improvements to the facility were implemented. The new 330 t/d annular-shaft kiln improved fuel economy, provide increased production capacity and provide long-term market competitiveness. A new 10 t/h hydrator improved production efficiency and in 1991, a wash plant was commissioned, providing better-quality stone feed to the kiln.
Since 1985 Havelock Lime has carried out several drilling programs [McGee (50 holes) and Samphill extension (28 holes) in 1988; Hicksville (19 and 9 holes in 1989 and 1991 respectively); as well as several holes in 1994-95 at the Samphill Quarry] to further extend the company's limestone reserves throughout the basin which according to a 1995 Goldcorp Inc. annual report was near 8.5 million tonnes.
In 1996, Havelock Lime's reputation as a marketer of quality lime products was enhanced by its qualification for the internationally recognized ISO 9002 quality assurance accreditation.
A new page was turned for Havelock Lime was turned in 1999 following a decision by Goldcorp to sell its Havelock division to Graymont Ltd. of Vancouver, British Columbia. Graymont, a privately owned Canadian corporation, is the third largest lime producing company in North America. The Havelock facility, renamed Graymont (NB) Inc., is closely associated with Graymont's three lime plants and associated quarries in Quebec.
Limestone requirements are partially supplied from the company's Samphill quarry with up to 400,000 t purchased annually from the neighboring Lafarge North America Inc. McGee quarry. In its 1997 Annual Report, Goldcorp Inc., Havelock's former parent company, had indicated that at the current rate of production Havelock Lime had limestone resources that would last approximately 30 years. Although not fully delineated, total resources from company holdings in the Havelock area were estimated >8,000,000 tonnes.
Graymont (NB) Inc. typically processes between 300,000 and 400,000 t of limestone as well as lesser amounts of high magnesium limestone. Chemical. process stone (for use as flux in nonferrous smeltering, and the pulp and paper industry are major markets, whereas pulverized stone finds use as a dusting agent in coal mines, a soil amendment for agricultural purposes, poultry grit, and various grades of construction aggregate. Havelock's Graymont (NB) Inc, remains the only source of calcined lime products (quick and hydrated lime) in Atlantic Canada.
Another well known company with former operations in the Havelock area is Lafarge Canada Inc. (subsidiary of Lafarge North America Inc.). Lafarge has operated several quarries at one time or another throughout the Havelock region with most developments established 5 km east of the village.
From 1952 to the early 1980s limestone from its quarry operation supported an adjacent cement manufacturing facility. After 1982, production of cement became limited to fulfilling market requirements for oil well and other specialty cements. Eventually access to limited markets and other operational costs forced a curtailment to cement production. The plant continued as a grinding operation for imported cement clinker from a company operation in Nova Scotia until 1987 when the Havelock production facility was permanently closed. Since that time Lafarge has maintained its quarry rights in the region supplying limestone to Graymont (NB) Inc., for the manufacture of various specialty cement products at a company cement plant in Nova Scotia and as a source of aggregate material to regional operations of Lafarge Construction Materials (i.e., ready-mix cement plants) on an as-required basis.
A new quarry operation, the McGee Quarry was opened in 1986, just north of Highway 880, less than 1 km east of the the former cement plant. This property, partially investigated in 1976, contains extensive reserves of high-calcium limestone. The McGee site, owned by Lafarge, is now operated by Graymont under a special agreement. Potential medium- to high-grade limestone (i.e., 50-53% CaO) resources are estimated to be fairly extensive on properties held under mining lease by Lafarge Canada Inc. although no specific values are publicly available. In addition, the company maintains a 288 ha claim block in the Springhill area several kilometres southwest of the former cement plant and its adjacent quarries.
Deposit Evaluation
The Havelock area maintains the largest identified reserves (several million tonnes) of medium to high calcium limestone in New Brunswick. Of the four major Gays River limestone facies identified in the area, only the wackestone-packstone facies constitutes a relatively inconsistent source of high calcium stone. However, due to its intimate association with the other, more extensive and voluminous, higher-grade facies, its presence does not appear to have a significant impact on the overall limestone quality in most areas.
At first glance it would appear that limestone resources in the Havelock area are extensive. However, it is reasonable to suggest that portions of the resource may not be chemically or physically suitable for certain applications. In addition significant parts of the resource may not be accessible or economically recoverable due to various cultural restrictions (e.g. housing and related land use restrictions) and physical restraints (e.g., poor drainage, excessive overburden thicknesses).
Limestone with more than 51% CaO and less than 2% MgO may account for approximately 40% of the total remaining resource base in the basin. Stone of this quality is currently available at three sites: the No.2 and McGee quarries of Lafarge Canada Inc. and Graymont's Samphill quarry. |