|
Evergreen wants core drilling treated as mining Coalbed methane company submits core drilling operations plan designed to establish foundation for future core-drilling projects in south-central Alaska Kristen Nelson Petroleum News Editor-in-Chief
Evergreen Resources Alaska’s plans for mineral core hole drilling in the Matanuska-Susitna area are under review by the Alaska Department of Natural Resources Division of Oil and Gas and other state and local agencies. Evergreen said the plan of operations “is designed to establish a foundation for future mineral core-drilling projects that will be proposed periodically throughout the region.”
The company is asking for exemption from some lease mitigation measures on grounds that core drilling should be regulated as mineral coring, not as oil and gas drilling.
The state said Evergreen is proposing to drill mineral core holes at seven possible locations to gather information on coal seams in the Mat-Su area. (See map on page A10.) These holes are “for geological information only and do not involve dewatering the coal seams or gas production,” the state said.
Evergreen’s initial plans call for five core holes this winter. The program is expected to last approximately eight weeks, beginning in December.
Three of the locations, Kashwitna Lake, Willow Fishhook and Sheep Creek, require state plans of operations because they are on state-owned surface and subsurface. Coring rig to be used Evergreen said its program will gather geologic information on coal seams in the upper Cook Inlet and eastern Susitna basins. “The purpose of the coring project is to gain geological information on the coal-bearing rock formations penetrated during the drilling, and to recover coal cores for further laboratory testing of their mineralogical, geological, and engineering properties,” Evergreen told the state.
Site preparation is expected to take a week or less at each location and coring each hole is expected to take one and a half to two weeks, with 24-hour per day operations.
Evergreen will use a core rig, similar to those used in the Alaska mineral industry. The rig will be truck mounted, and the company said “the rig’s small size makes it easy to move around and access drill sites along existing trails and easements and results in a small footprint with minimal surface disturbance.”
The company said no gas production testing will be done during this operation, and the holes will not be drilled on the tops of identified geologic structures. “The proposed core-drilling program is directly comparable to mineral core drilling that coal exploration companies have done for many years in the lower Matanuska-Susitna Valley, through similar coal-bearing formations,” Evergreen said. Exemptions requested from mitigation measures Evergreen is requesting exemptions from shallow gas lease mitigation measures because it will be “drilling mineral exploration core holes of small diameter.”
Mitigation measures attached to shallow gas leases govern drilling waste. Evergreen said state statutes exempt mineral drilling from such requirements, and told the state it “believes this mitigation measure provides an excessive burden for the proposed coring operation, and requests an exception from requiring the drill cuttings to be removed from the drill site on the grounds that these discharges are statutorily exempt from requiring disposal permits, and will not constitute a new solid waste disposal site and therefore have been determined to not result in adverse environmental impacts.”
Drilling additives which Evergreen will use in drilling the core holes — soda ash, cellulose fiber, bentonite and barite — “are widely used by Alaska’s water well and mineral coring operations,” the company said.
Evergreen said drilling waste from the coring operation will be small volumes of predominately native rock material. “The proposed core drilling is comparable to mineral exploration core drilling discharges that have been generally recognized to produce minimal consequences and are typically discharged directly to the surface,” Evergreen said. Five proposed core holes, two alternate sites One location is north of Palmer, the others are in the vicinity of the Parks Highway from northwest of Houston north to Sheep Creek, with one site northeast of Willow off the Willow Fishhook Road.
The proposed sites are Little Su No. 1, Houston Pit No. 1, Willow Fishhook No. 1, Kashwitna Lake No. 1 and Sheep Creek No. 1. The alternatives are Willow No. 1 and Caswell Creek No. 1. Evergreen’s proposed schedule shows the first core hole would be drilled at Little Su No. 1 beginning in December and the last core hole at Sheep Creek No. 1 in January. “Our preference is to drill the Little Su No. 1 well first (the outlying well which is north of Palmer), and then move progressively up the Parks Highway toward Sheep Creek with the last core hole,” the company said. First site north of Palmer, rest near Parks Highway Little Su No. 1 is the easternmost boring, approximately eight miles north of Palmer off the east side of Fishhook-Willow Road on a 110 acre privately owned parcel. The private landowner owns the subsurface oil and gas rights, but underground coal, for mining purposes, is the property of the state. Evergreen said that access to this site, a treeless meadow, will be via a Matanuska Electric Association power line corridor. The landowner has signed a letter of non-objection for the proposed activities.
The other proposed sites are from Houston north, along the Parks Highway.
Houston Pit No. 1 is just south of Zero Lake Road, across from the old Houston coal mine strip pit, and some 1.5 miles northwest of the Houston business district. “The actual drill site will be located on land previously disturbed by past mining operations,” Evergreen said, on surface land owned by the City of Houston and subsurface owned by the Alaska Mental Health Trust. There was an underground mine in the area in the late 1930s and strip mining in the 1940s and 1950s, and Evergreen said the core hole will be drilled in an area built up with tailings from the strip mining operations. Four of five proposed sites associated with gravel Willow Fishhook No. 1 is along the Willow Fishhook Road, north of the road on a 12-acre parcel owned by the state. A land use permit is in place on this parcel for extraction of gravel, Evergreen said, and the core site will be in the gravel pit. There is an access road, and the company said some “local leveling of the gravel pit may be necessary to accommodate the drilling and support equipment,” but no new disturbance will be made at the site.
Kashwitna Lake No. 1 is some 20 miles north of Houston on the Parks Highway on state property north of Kashwitna Lake and west of the highway. Evergreen said the surface of this area has been previously disturbed, “creating an access road to the small linear pond that appears to have been an old gravel pit.” The company said the Alaska Department of Fish and Game have determined there are no fish in the pond, which was probably excavated during highway construction, and has since filled with water.
“There is a small parking spot at this location, which may need to be enlarged slightly to accommodate the various pieces of drilling and supporting equipment,” Evergreen said.
Sheep Creek No. 1 is approximately 32 miles north of Houston on the Parks Highway in a large gravel pit west of the Parks Highway, about a half-mile south of the point where Sheep Creek crosses under the highway. The state owns both surface and subsurface rights.
Access is by an existing gravel road to the large state-owned gravel pit and the core site is near the eastern end of the large gravel pit.
“The area is significantly disturbed,” Evergreen said.
| 