DISC Drill

The U.S. Ice Drilling Program is planning use of its drills for the coming decade. If you intend to submit a proposal to the NSF that would require use of the DISC Drill, please send an email expressing your intent to Icedrill@Dartmouth.edu by October 1.

Deep drilling at Hercules Dome will be conducted using the Foro 3000 Drill. A comparison of Foro 3000 Drill and DISC Drill capabilities and associated logistics requirements is available online and summarized in the table below.

Thank you for contributing to future planning for the U.S. Ice Drilling Program!

In early April, IDP-WI coordinated with staff at Port Hueneme to return cargo from Antarctica. Returned equipment included the Hand Augers used during the 2018-2019 season, the Intermediate Deep Logging Winch and the Sediment Laden Lake Ice Drill. In addition, several crates of DISC Drill equipment and the MECC (Mobile Expandable Container Configuration) machine shop returned after over a decade on the ice. The DISC Drill equipment and MECC were slowly removed from WAIS Divide on flights of opportunity.

The IDPO Ice Core Working Group (ICWG) meeting was held in Alexandria, VA on January 22, 2018. Scientific findings from recent drilling activities were presented, and future possible investigations in Greenland and Antarctica were identified and discussed. The ICWG reaffirmed Hercules Dome as the priority deep drilling site for the community, due to its key location in archiving evidence of past dramatic changes in the West Antarctic Ice Sheet. Science-technology tradeoffs were discussed regarding use of the Foro 3000 Drill versus the DISC Drill at Hercules Dome; the DISC Drill delivers a larger volume of ice, however the Foro 3000 Drill has much lower logistical requirements. The ICWG came to agreement that the Foro 3000 Drill will be the drill of choice for this important site.

Winkie Drill
In preparation for the upcoming field season in Antarctica, IDDO outfitted the Winkie Drill with a new electric motor and larger diameter core barrel for collecting 76 mm diameter cores. Testing of the updated drill is ongoing at the IDDO warehouse. The Winkie Drill will be shipped to Antarctica in September where it will be used to collect dirty ice cores in Ong Valley, Antarctica, to depths of up to 20 meters.

Stampfli 2-Inch Drill
IDDO shipped the very lightweight, agile Stampfli 2-Inch Drill system to Greenland for field testing in June in conjunction with a funded field project taking place at Summit Station. The small, solar-powered drill operated well during the field test, producing 58 meters of core. Based on the results of the field test, IDDO is working to make minor repairs and modifications to the drill, procure spare parts, and develop a lightweight packing strategy for this system. The system could be ready for deployment and PI operation as early as the 2017-2018 Antarctic field season.

Rapid Air Movement (RAM) Drill
A conceptual design for extensive weight reduction based on the revised science requirements was completed in July. The conceptual design was presented to community scientists Sridhar Anandakrishnan and Paul Winberry for input in early August. Following that external review and any necessary modifications to the design, IDDO plans to begin purchasing primary components for the lighter-weight RAM Drill system in September/October.

Sediment Laden Lake Ice Drill
The Sediment Laden Lake Ice Drill is a lightweight, field portable hot water drill for drilling through several meters of sediment-laden lake ice. Following the April external design review and the ordering of components in May, IDDO began assembly of the system in June and plans to complete simple functionality testing at the IDDO warehouse in late summer and early fall. The system could be ready for deployment and PI operation as early as the 2018 Arctic field season.

Foro 3000 Drill
The Design Review of the Foro 3000 Drill was held on June 6. The Design Review was a virtual meeting where IDDO presented the Conceptual Design for the drill, and community scientists Eric Steig, Ed Brook, and T.J. Fudge provided feedback from the scientist/user perspective. The Conceptual Design for the drill is now complete. The Foro 3000 Drill is conceptually the same design as the existing Intermediate Depth Drill, but with a depth range extended to 3000 meters and drill run length extended from 2-meters to 3-meters.

DISC Drill versus Foro 3000 Analysis
Per discussions between IDPO, IDDO and community scientists, the next deep U.S. ice coring project will likely target Hercules Dome, Antarctica. IDDO, with assistance from Antarctic Support Contract and IDPO, is currently working with community representatives on a DISC Drill versus Foro 3000 Drill analysis, to help determine which system should be used for drilling at Hercules Dome. The analysis results will be summarized into a report for use by NSF and the science community.

Winch Simulator
Following discussions with Mary Albert and PI Ryan Bay, and due to decreased interest by the science community in IDDO purchasing an off-the-shelf winch simulator unit or designing a custom unit, IDDO plans to design a simple simulator circuit for each logging winch in inventory. IDDO envisions providing these circuit designs to PIs for building at their own institutions. PIs could then perform limited pre-deployment testing on their logging tools; however, IDDO will still encourage PIs to travel to Madison to test logging tools on the actual winches to be deployed. IDDO plans to complete design of the simulator circuits by the end of October.

Agile Sub-Ice Geological Drill
During the fourth quarter, IDDO completed all of the system modifications, repairs and upgrades identified during testing performed in the second quarter. The system was shipped to Port Hueneme, CA, in mid-September for use this coming Antarctic field season on PI John Stone's project (see Field Support to Antarctic Projects above).

Winkie Drill
During the quarter, IDDO completed the fabrication, assembly, and modifications of the Winkie Drill. On 9/16/16, the Winkie Drill system was shipped to Port Hueneme, CA, for its first Antarctic deployment on PI Mukhopadhyay's project (see Field Support to Antarctic Projects above).

Rapid Air Movement (RAM) Drill
During the quarter, IDDO continued review of the existing sled design and its suitability for use with a reverse circulation dual walled pipe drill. With interest by both the seismic and physics communities on modification and use of the RAM Drill, IDDO plans to work with IDPO in PY 2017 (Nov 1, 2016 - October 31, 2017) to develop updated science requirements for the drill, upon which all subsequent modifications and upgrades will be based. During the quarter, IDDO also completed necessary paperwork for participation in a capstone project at the Colorado School of Mines (CSM). The project was accepted for the current school year where CSM students will study air flow and down hole tooling analysis for the RAM Drill.

MAgIC Drill/Intermediate Depth Drill-Light
Throughout PY 2016, IDDO worked with IDPO and community scientists to develop and refine science requirements for a drill similar to the 1500 m Intermediate Depth Drill, but with a depth target between 400-700 meters and with a much-reduced logistics burden to allow for coring on remote glaciers, for instance, in Alaska. IDDO is working with IDPO and interested community scientists to develop an approach to the desired equipment, and is in the process of compiling system options to present to the community. A decision on the naming of the new system, and whether or not it will be built, will be determined once the science requirements are finalized.

Foro Drill
IDDO continued to procure drill components for the Foro Drill during the quarter as planned, including a slip ring and a winch frame assembly. Design of the cable was finalized and the cable subsequently ordered in early August. The control box layout was reviewed, the mechanical design of the box was finalized, and custom aluminum cases and faceplates were procured.

Deep Ice Sheet Coring (DISC) Drill
Any further development work for the DISC Drill remains on hold, until the science community identifies if/when the system will next be deployed.

Agile Sub-Ice Geological Drill
During the third quarter, IDDO worked to complete system modifications, repairs and upgrades identified during testing performed in the second quarter. The Agile Sub-Ice Geological Drill is expected to ship to Antarctica in September. Validation and verification are now underway and documentation will be completed in the fourth quarter.

Winkie Drill
During the third quarter, IDDO completed an internal system design review as well as all necessary fabrication, assembly, and modifications of the Winkie Drill. Multi-round system testing was completed, including ice drilling with a newly-designed air chip transport system and modified Forstner and Irwin bits, coring through an ice/rock interface with multiple layers of ice and different sizes of granite rocks using two different types of mixed-media coring bits and a range of Isopar K temperatures, and coring solid granite with three different types of coring bits and two types of drilling fluid (Isopar K and water). System testing was very successful and helped inform selection of drilling/coring bits for a variety of ice/rock conditions the drill may encounter in the field. In conjunction with system testing, IDDO completed two days of operational training, conducted by Earl Maynard, a Winkie Drill expert, in Madison in July 2016. IDDO continued minor system modifications and started final procurement of replacement and spare parts.

Rapid Air Movement (RAM) Drill
During the quarter, IDDO continued researching multiple approaches for RAM Drill modification and decided to primarily focus on a dual walled pipe drill design that looks more promising than a dual walled hose design or a design based on a new standard hose reel assembly. IDDO started reviewing the existing sled design and its suitability for use with a reverse circulation dual walled pipe drill.

MAgIC Drill/Intermediate Depth Drill-Light
During the quarter, IDDO continued working with IDPO and community scientists to refine science requirements for a drill based on the 1,500 m Intermediate Depth Drill (IDD), but with a depth target between 400-700 m and with a much-reduced logistics burden to allow for coring on remote glaciers. IDDO sent the next round of comments/edits of the IDPO Science Requirements to IDPO on 6/20/16. A decision on the naming of the new system, and whether or not it will be built, is ongoing.

Foro Drill
IDDO procured several major Foro Drill components during the quarter as planned, including a Lebus core for the winch drum, a winch motor, a winch motor gearbox, a motor VFD and a pre-fabricated cable assembly for the winch control loop. IDDO finalized the design and ordered a new four-conductor cable in early August. All components for testing of the winch control loop were received. IDDO completed a dimensional report on the winch Lebus core. This core was sent to Innovative Machine Specialists for final assembly, including heat treatment, anodizing and machining. The control box layout was reviewed, and IDDO began finalizing the mechanical design of the box.

Deep Ice Sheet Coring (DISC) Drill
Any further development work for the DISC Drill remains on hold, until the science community identifies if/when the system will next be deployed.

Agile Sub-Ice Geological Drill
During the Second Quarter, IDDO initiated full-scale system testing of the Agile Sub-Ice Geological (ASIG) Drill outside of Madison, Wisconsin on the UW Physical Sciences Lab (PSL) campus. IDDO engineers, a contract driller and a trainer from the rig vendor, Multi-Power Products, LLC, were able to test a variety of operations, per the Test Plan drafted by IDDO Project Manager Chris Gibson, including the coring of ice, concrete, solid granite and mixed media. The team was also able to tune the rig, refine fuel and drilling fluid consumption rates, determine the expected operational parameters of the system, such as penetration rates, and identify and refine the spare parts list. The rig performed reliably and is expected to meet or surpass all related science requirements. IDDO hosted several visitors to the test site on February 26, 2016, including Bill Eustes, Blaise Stephanus and Mark Twickler from IDPO, as well as PI John Stone, as the drill system will be used first for his upcoming project in 2016-2017 near Pirrit Hills in Antarctica. Leah Street from ASC, in Madison on other business, was also able to visit the site, as well as several other IDDO personnel. Late in the quarter, IDDO engineers quickly transitioned to system modifications, repairs and upgrades, in anticipation of shipping the system to Antarctica in September.

Winkie Drill
During the Second Quarter, IDDO continued its modifications and upgrades to the off-the-shelf Winkie Drill purchased from Minex. Early in the quarter, IDDO was able to test its adaptations of auger flights during the Rapid Access Ice Drill (RAID) Auger and Packer Test near McMurdo Station. Important information was gained regarding penetration rates, expected fuel consumption, and the augers' ability to transport ice chips to the surface. Taking advantage of the ASIG Drill test set up, the transportation of ice chips by air was tested as a proof of concept for drilling options in the deep field. Later in the quarter, IDDO identified two types of mixed media coring bits, completed fabrication of a rig base for the system to support the drill and evenly distribute loads across the snow surface during core breaks, completed installation and testing of a variable frequency motor drive for the mud pump, and completed modifications of a drill fluid filtration drum. IDDO will continue its work into the Third Quarter, and also plans to complete additional testing and training in Madison in July 2016, prior to shipping the system to Antarctica in September.

Rapid Air Movement Drill
During the quarter, IDDO began researching a new hose reel design for the Rapid Air Movement (RAM) Drill. IDDO also explored dual-wall hose designs and rigid, lightweight aluminum pipe applications as it looks to lighten and lessen the drill's logistics for future deployments. IDDO engineers also corresponded with engineers in the Chinese drilling program, as they are investigating similar technologies.

MAgIC Drill/Intermediate Depth Drill-Light
During the quarter, IDDO worked with IDPO and community scientists to develop and refine science requirements for a drill similar to the 1,500 meter Intermediate Depth Drill (IDD), but with a depth target between 500-900 meters and with a much-reduced logistics burden to allow for coring on remote glaciers, for instance, in Alaska. A decision on the naming of the new system, and whether or not it will be built, should be resolved in the Third or Fourth Quarters.

Foro Drill
IDDO ramped up its design of the Foro Drill during the quarter, corresponding with winch drum and other winch component manufacturers. IDDO initiated procurement of components for prototyping the winch control system and building the new Foro control box.

Deep Ice Sheet Coring Drill
IDDO has temporarily put any further development work for the Deep Ice Sheet Coring (DISC) Drill on hold, until the science community identifies if/when the system will next be deployed. Some minor maintenance and cleaning up of the LabVIEW software was completed during the quarter. A good portion of the DISC Drill cargo also returned from Antarctica in April, and is being unpacked and dried.

Agile Sub-Ice Geological Drill
During the First Quarter (Nov-Jan), initial sub-system testing was concluded for the Agile Sub-Ice Geological (ASIG) Drill components, and preparations were ramped up for the upcoming North American Test of the drill. A temporary ice well was constructed outside of Madison on the UW Physical Sciences Lab property. Project Manager Chris Gibson and other IDDO engineers worked to ready all equipment for the multi-week test planned for late February 2016. Extensive work on documentation was also initiated, including refinement of the test plan, drafting of an equipment lab testing report, updating of the system's Failure Modes and Effects Analysis (FMEA) document, and creation of a safety training presentation.

Deep Ice Sheet Coring Drill
As IDDO prepares to make modifications, upgrades, and repairs to the Deep Ice Sheet Coring (DISC) Drill equipment in preparation for its future use in Antarctica, IDDO Project Manager Alex Shturmakov and engineer Josh Goetz reviewed drilling logs and reports in an effort to understand and prioritize necessary modifications and upgrades. In the coming months, IDDO plans to work on preliminary sonde modifications in an effort to collect 4-meter long cores per run, to determine an optimal method of installing heavy equipment in the field without deploying the large blue gantry crane, and to upgrade the aging control system hardware to allow for optimization of the LabVIEW software.

Several other projects supported by IDPO-IDDO were also successfully brought to a close during the quarter. Drilling efforts for the cosmogenic C-14 project on Taylor Glacier were completed for the third and final year. Out at Allan Hills, an IDDO driller utilized an Eclipse Drill to successfully core three holes to bedrock, collecting precious ancient ice. A second Eclipse Drill project was completed at South Pole Station. Finally, after years of programmatic delays, IDDO was able to conclude its operations related to use of the DISC Drill at WAIS Divide. All equipment is now disassembled, packed, labeled and ready for return to the U.S. as flights allow. IDDO also successfully extended the borehole casing to allow for future logging operations, including planned logging during the 2016-2017 field season.

South Pole Ice Core (PI Aydin)
An IDDO team of seven engineers and drillers, led by Lead Driller Jay Johnson, successfully completed this two-year drilling endeavor at South Pole Station, achieving a final borehole depth of 1751 meters, 251 meters beyond the original goal of the project. All necessary retro cargo was readied for vessel and COMAIR transport back to the U.S., whereas the drill tent and other items were winterized for use again in 2016-2017.

WAIS Divide Deep (PI Albert)
IDDO Driller Jim Koehler arrived at WAIS Divide on 1/14/16, following weather and aircraft delays, and worked expediently to prepare the remaining DISC Drill items for return shipment to the U.S. Koehler also worked with ASC personnel to extend the borehole casing to two feet above the Arch floor level.

Taylor Glacier Blue Ice Cores (PI Petrenko)
IDDO Driller Mike Jayred operated the Blue Ice Drill (BID) in support of PI Vas Petrenko's C-14 of atmospheric methane fieldwork at Taylor Glacier. All science samples were successfully collected, with over 480 meters of core drilled over 35 drilling days. In total, over 40 holes were completed through approximately 530 drill runs. IDDO support of this three-year project is now concluded.

Climate Controls on Aerosol Fluxes in Taylor Valley (PI Aciego)
IDDO Driller Mike Jayred operated the Blue Ice Drill (BID) in support of PI Sarah Aciego's aerosol fluxes fieldwork at Taylor Glacier. All science samples were successfully collected in early November 2015, with 20 meters of core collected during this short duration project.

Allan Hills (PI Higgins)
IDDO Driller Mike Waszkiewicz operated an IDDO Eclipse Drill at Allan Hills in support of PI John Higgins' ancient ice fieldwork. All science samples were successfully collected. Each of the two planned holes were drilled to bedrock, with the first hole drilled to a depth of 100 meters and the second hole to a depth of 205 meters. The team was also able to re-enter a third hole that was originally drilled in 2011, coring an additional 20 meters of what is believed to be million year old ice.

South Pole Firn Air (PI Sowers)
Trevor Popp, an American driller and scientist working at the Centre for Ice and Climate in Copenhagen, Denmark, operated an IDDO Eclipse Drill at South Pole in support of PI Todd Sowers' firn air sampling campaign. In early November 2015, Popp set up the drill and began drilling without incident. Firn air sampling was progressing well until the firn air bladder provided by and operated by the science team became stuck in the borehole at 100 meters depth. Following unsuccessful efforts by the science team, IDDO, and ASC to retrieve the firn air sampling equipment, the hole was abandoned and efforts were redirected to drilling of the second hole, which was successfully drilled to 128 meters. Core quality was excellent throughout and the penetration rate was exceptional.

Hand Augers
During the 2015-2016 Antarctic field season, IDDO supported ten investigators through the deployment of a variety of hand auger and Sidewinder kits. The hand auger kits are currently en-route back to the U.S. via the cargo vessel.

Crary Ice Rise Shot Holes (PI Conway)
IDDO supplied PIs Twit Conway and Paul Winberry with a Small Hot Water Drill to create shot holes for their Crary Ice Rise seismic work. All shot holes were successfully drilled by the science team, and the equipment is currently onboard the cargo vessel headed to the U.S.

Exposed Rock Beneath the WAIS (PI Stone)
In anticipation of the upcoming 2016-2017 fieldwork, IDDO shipped borehole casing and drill rod for the ASIG Drill to Antarctica via the resupply vessel. These items are planned for use during the 2016-2017 field season to support PI John Stone's fieldwork near Pirrit Hills. The borehole casing and drill rods were shipped early to reduce ASC's shipping costs and to allow the cargo to be flown to West Antarctica in 2016-2017 on flights of opportunity.

With the 2013-2014 field season at WAIS Divide canceled due to the government shutdown, IDDO re-planned its efforts for 2014-2015 for disassembly and packing of the DISC Drill at the site. Four IDDO personnel deployed from the U.S. in early December, and three ended up facing 20 days of aircraft and weather delays in McMurdo. With excellent teamwork between IDDO, ASC, and the borehole logging scientists (also at WAIS Divide this year), as well as NSF and ASC's willingness to extend the field season at WAIS Divide in light of the delays, the teams were able to successfully complete the majority of logging objectives for the season! In addition the team was able to dismantle much of the DISC Drill equipment in a very short amount of time. A portion of the drill will now return to Madison and the rest will remain at WAIS Divide over winter until future flight opportunities in 2015-2016. IDDO and ASC will continue to work closely together to plan for disassembly and removal of the remaining items from the drill arch, including IDDO's yellow gantry crane, the crane rails, and the drill control room, as well as to coordinate extending of the borehole casing up to the arch floor level next year.

Intermediate Depth Drill
IDDO continued work on the procurement of the Intermediate Depth Drill (IDD) parts and components and started system fabrication, assembly, and components testing. The final assembly of the entire system is planned to be completed by September 30, 2013.

IDPO-IDDO continued to work with the NSF Arctic Logistic contractor (CH2M Hill Polar Services) on the field logistics required for the 2014 IDD field test in Greenland. The Estisol-140 drilling fluid and borehole casing needed for the test were also purchased and are currently on vessel for delivery in Thule, Greenland for subsequent transportation to the field test site (the proposed Isi Station; ~3 miles due north of Summit Station) via the Greenland Traverse in April 2014.

Deep Logging Winch
The Deep Logging Winch system is currently in production and is scheduled for delivery to IDDO by August 15th by Markey Machinery Co. IDDO designed and placed a purchase order for the winch sled and, working with the winch manufacturer, modified the winch control system.

Blue Ice Drill-Deep
After finishing the design and fabrication of a new anti-torque and modifications of the cutter heads for the Blue Ice Drill-Deep (BID-Deep), IDDO successfully completed testing of firn coring capabilities in Greenland in May of 2013. IDDO plans to finish the entire BID-Deep design by September 30, 2013.

DISC Drill/Replicate Coring System
By June of 2013, IDDO completed the preparation of many DISC/Replicate Coring System components for storage. Small repairs, upgrades, and the necessary component maintenance have been completed. IDDO also developed a comprehensive list of all mechanical and electrical subsystem modifications and repairs needed for the drill's future re-deployment.

Science Advisory Board Meeting
IDPO held the IDPO Science Advisory Board (SAB) annual meeting on March 14-15, 2013 at the Hilton in Arlington, VA, where members of the SAB, IDPO, IDDO, and NSF shared information and discussed aspects of the Long Range Science Plan. The draft 2013 Long Range Science Plan will be released shortly, and comments and input from the community will be requested. The minutes from the SAB meeting are being drafted and, when finished, will be available for download at http://icedrill.org/about/sab.shtml.

DISC Drill - Updated Science Requirements
IDPO discussed with IDDO the need for updated Science Requirements for long range planning for the DISC Drill. IDPO will work with the community and with IDDO this summer to revisit the requirements and establish updated science requirements that will establish a direction for work on the DISC Drill in coming years, including preparation for very cold conditions.

The deep drilling at WAIS Divide, Antarctica has come to a close. It took eight field seasons to prepare the remote field camp, to drill the 3,405 meter deep ice core (the longest ice core in U.S. history), and to collect the 285 meters of valuable replicate core (see story above), but we did it. On February 5, the National Science Foundation (NSF) released a press release celebrating this historic accomplishment. In case you didn't see the press release, it is available at:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=126761&org=NSF&from=news

In addition to the NSF press release, The Antarctic Sun also released a great story about the success of replicate coring at WAIS Divide this season. The story is available at:
http://antarcticsun.usap.gov/science/contenthandler.cfm?id=2788

For the first time, significant innovations in ice drilling engineering are providing scientists with replicate ice cores from targeted depths and directions in the ice sheet!

The newly developed, state-of-the-art Replicate Ice Coring System was deployed in December 2012 to re-enter the 6.5-inch diameter deep borehole at WAIS Divide, Antarctica, and successfully allowed the researchers to drill through the wall of the 3,405 meter deep parent borehole and collect a total of 285 meters of additional core from five of the most interesting time periods in the WAIS Divide climate record.

The Replicate Ice Coring System is capable of retrieving additional ice cores from specific depths on the uphill side of the main (parent) borehole. The Replicate Coring technique, developed and tested by the IDDO engineers as part of the Deep Ice Sheet Coring (DISC) Drill, is a key advance, because it allows scientists to take samples from specific levels of a parent borehole without impeding the hole itself, leaving the parent borehole open for future logging of information.

The Replicate Ice Coring System collects additional ice at depths of interest by deploying into an existing borehole and then deviating from it. The drill uses two steering actuator sections to tilt itself in the parent borehole by applying sidewards force against the borehole wall. In the first step of the process, the broaching cutter head is deployed to the target depth. Using the actuators, the drill is tipped to the high ("up hill") side of the borehole to engage the cutters. Ice is removed in repeated passes of approximately 15 meters in the up-stroke. In the second step of the process, a milling head is deployed and creates a landing for the coring head. In the third step of the process, a coring head removes a 20 mm kerf and allows a 108 mm diameter core to enter the core barrel. Two meters of core are removed per trip. The coring is repeated until all of the desired replicate ice from the target depth is obtained.

The Replicate Ice Coring System builds on the existing infrastructure of the DISC Drill and thus requires substantial logistics and infrastructure support. However, the design and engineering behind the system is such that it can be scaled down for use with smaller, more agile drilling systems as well. The downhole portion of the DISC Drill, the sonde, was significantly modified to meet the requirements of steering out of the parent hole. The major components of the replicate sonde are described below.

Cable Interface Section
The existing cable interface section of the DISC Drill provides the connection to 4km of fiber optic cable.

Upper Actuator Section
The upper actuator section steers the drill, and with the anti-torque levels extended keeps the drill from spinning during cutting operations.

Instrument Section
The instrument section provides power and communications to operate the drill.

Lower Actuator Section
The lower actuator is identical to the upper actuator, but is configured with discs on the levers to provide smooth navigation.

Pump/Motor Section
The pump/motor section has a powerful pump for chip transport and contains the cutter motor.

Lower Sonde
The lower sonde includes chip barrels that collect the chips that are cut during coring, a core barrel to collect the core, and the coring head. The lower sonde can be assembled in multiple configurations to meet the needs of the different stages of the replicate coring process.

Scientists interested in using the DISC Drill in the future need to work with the Ice Drilling Program Office - Science Advisory Board (http://icedrill.org/about/sab.shtml) to formulate their plans and to ensure that their science is articulated in the Long Range Science Plan (http://icedrill.org/scientists/scientists.shtml#scienceplan), which is updated annually each spring. The current schedule for the DISC Drill is as follows:

• Dec 2012 - Jan 2013: Replicate coring at WAIS Divide, Antarctica
• Dec 2013: Disassemble and pack DISC Drill at WAIS Divide
• Nov 2014 - Jan 2015: Disassemble arch and prepare for traverse back to McMurdo Station
• Nov 2015 - Jan 2016: Traverse DISC Drill from WAIS Divide to McMurdo Station
• Feb 2016: Retrograde DISC Drill to CONUS via vessel
• May 2016: DISC Drill arrives in Madison, WI
• May 2016 - Nov 2017: Inspect, re-build, re-design and replace drill system components if necessary

Given the anticipated schedule above, the DISC Drill could be ready for shipment to the field again in late 2017. For the latest information and schedule for the DISC Drill, visit: https://icedrill.org/equipment/deep-ice-sheet-coring-drill

After review of data collected during the previous Antarctic field season and in preparation for the 2012-2013 WAIS Divide field season, IDDO has designed and fabricated a sophisticated test set-up to determine the root causes of shortcomings experienced by the Replicate Coring system. During the third quarter, IDDO was able to complete a major portion of a "sonde-in-the-borehole" test of the Replicate Coring System to determine drill sonde deflection, to verify the mechanical system analyses and to measure force at cutter head for given set points. This will assist IDDO engineers in making system modifications necessary to successfully collect replicate core during the next field season. The root cause of the intermittent instrument section faults witnessed in the field and during the system test in Madison was identified; the fix is designed and is currently being implemented. Troubleshooting of actuator motors, pressure testing of motor sections and modifications of instrument section circuit boards and LabVIEW software modifications were all successfully completed. System testing and modifications will continue into the Fourth Quarter. The large DISC Drill winch motor was also successfully repaired, rebuilt and returned to IDDO.

This season's maiden voyage of the DISC Drill's Replicate Coring capability proved to be both challenging and enlightening. While no core was obtained, IDDO engineers gained a great deal of insight into the process of creating a deviation for replicate coring. A new borehole camera proved valuable in assessing the results of the deviation effort. The video and operating data are being analyzed to aid in the modification to replicate components in order to improve chances of success during the upcoming replicate coring production season. IDDO has held several internal design reviews and, in addition, IDPO led an external review of Replicate Coring modifications held in Madison on March 27-28. Dr. George Cooper, Emeritus Professor at U.C. Berkeley and Dr. Alfred Eustes, Associate Professor at Colorado School of Mines participated as external reviewers. The effort to carefully review and analyze the recent field season experience has led to the design of tests and test fixtures needed to improve the replicate coring system.

IDDO completed the bench testing of replicate coring components prior to their being shipped to WAIS Divide. In addition, IDDO designed and built a new inclinometer control board with greater accuracy for positioning the sonde in the borehole for replicate coring, developed a bumper for the broaching cutter head to protect the borehole during the lowering and raising of the drill sonde, and designed and built a downhole camera system. IDDO conducted field-testing of the replicate coring system at WAIS Divide in January 2012, and the system will be used for production drilling at WAIS Divide during the 2012-13 field season.

For more information about the Replicate Coring System, visit: https://icedrill.org/equipment/replicate-ice-coring-system

On December 31, 2011, the drilling of the Antarctic WAIS Divide ice core was successfully completed. The DISC Drill produced excellent quality core over the entire 3,405 m depth, including through the technically challenging warm ice. This significant achievement was the culmination of over a decade of work including the design and construction of the DISC Drill by IDDO and its predecessor ICDS.

The ice core retrieved from the site is anticipated to yield the first high-resolution southern hemisphere record of greenhouse gases and climate comparable to the Greenland records, and will contribute significantly to improved understanding of climate variability over the last 62,000 years. Unlike the Greenland cores, however, the WAIS Divide ice core will also provide a record of carbon dioxide; and that record will have a higher time-resolution during the transition from the last glacial period to the current warm interval than any other existing ice core record.

IDDO completed fabrication and bench testing of the DISC Drill's Replicate Coring System, and plans to conduct field-testing of the system at WAIS Divide in the latter part of the 2011-2012 Antarctic field season. Production drilling with the replicate coring system at WAIS Divide is planned for the 2012- 2013 Antarctic field season.

For the latest news regarding 2011-2012 WAIS Divide field season progress, visit: http://waisdivide.unh.edu

The first-ever Replicate Ice Coring technology is progressing toward its debut in the field next year (January 2012) at WAIS Divide as IDDO engineers design, assemble, and test a system that will allow the DISC Drill to be steered and recover cores from branches deviating from the main borehole. This new technology enables gathering of additional ice core samples containing key climate information on abrupt changes, drilled from targeted depths kilometers beneath the ice surface.

On January 28, 2011, the DISC Drill reached its much-anticipated bottom depth of 3,331 meters at WAIS Divide, Antarctica. Despite a field season fraught with challenges, the drill crew surpassed previous depth records set at Dome Fuji, Dome C and GISP-2. On January 17, 2011, the WAIS Divide core became the deepest U.S. ice core ever drilled, surpassing the GISP-2 depth of 3,056 meters! For more information about the field season, visit: http://waisdivide.unh.edu/news/index.shtml

The second quarter FY2011 yielded success on many fronts for IDPO and IDDO. Of particular note is the reaching of the drilling goal of 3,331 meters using the DISC Drill at WAIS Divide, Antarctica, becoming the deepest U.S. ice core ever drilled. The newly-developed Blue Ice Drill achieved and surpassed its design requirements at Taylor Valley, Antarctica for drilling large volumes of ice in a short amount of time; over 600 meters of high quality, large (9.5-inch diameter) ice core was recovered at a rate faster than anticipated. IDPO worked with the community and with IDDO to discuss implications of the science requirements for the future intermediate depth drill design, cost estimates, and potential collaborations. The most critical issues currently facing IDDO are the repair and updating of the DISC Drill after the 2010-2011 WAIS Divide field season and the development of the DISC Drill Replicate Coring System, which is scheduled for testing at WAIS Divide during the 2011-2012 Antarctic field season.

The mechanical design and testing of the Replicate Coring System is a little ahead of schedule. The electronics design is somewhat delayed due to the problems with not completing the DISC Drill motor controllers prior to the start of the 2010-11 WAIS Divide field season. This delay plus the need to correct the problems experienced with the DISC motor controllers at WAIS Divide will impact the cost of completing the design, fabrication, and testing of the electronics systems for the Replicate Coring system. However, IDDO feels confident that the Replicate Coring system will still be ready for use at WAIS Divide during the 2011-12 field season.

A number of problems with the DISC Drill sondes (primarily the motor controllers and leaking housings) manifested themselves at WAIS Divide this season. While problems that require correction after the season are expected, these appear to be more serious than normal and are expected to require more effort to correct. The additional effort needed to make the repairs and modifications cannot be estimated until the drillers and the equipment return from the field and the equipment is assessed.

A variety of Antarctic field projects were launched this austral field season, including the final season of deep drilling the main core at the WAIS Divide site, and shallow drilling endeavors at Allan Hills, WAIS, Taylor Glacier, and access through the ice at Lake Vida.

WAIS Divide Ice Core - Deep
Despite problems with noisy control boards and fluid leakage into the sonde, good progress was made. The DISC Drill continued to produce ice cores of excellent core quality and on January 28, 2010 the season's depth goal of 3,330 meters was successfully reached.

Allan Hills Coring
Coring was successfully completed by driller Mike Waszkiewicz, with holes of 229 and 129 meters providing all the ice that PI Andrei Kurbatov needed.

WAIS Shallow Cores
Coring was successfully completed by driller Lou Albershardt, with three ice cores drilled (59, 112, and 62 meters) at three sites on the Pine Island and Thwaites Glaciers.

Taylor Glacier
Despite broken gearboxes early in season, PI Jeff Severinghaus reported that drillers Tanner Kuhl and Robb Kulin produced core with the newly designed Blue Ice Drill twice as fast as specified in the science requirements. In addition, the science goal of producing 7000 kg of ice with the drill was achieved.

Lake Vida Access
Driller Jay Kyne used the Prairie Dog Drill to complete holes to 27 and 20.5 meters depth in ice thicker and dirtier than expected by PI Peter Doran. The drill was stuck in the second hole and, after discussions between RPSC and NSF, abandoned to avoid any potential environmental damage in recovery.

The community proposes to begin replicate coring at WAIS Divide during the 2011-2012 Antarctic field season. The conceptual design of the Replicate Coring System was completed in FFY2009 and substantial progress was made in FFY2010 in translating the replicate coring concept into a detailed mechanical design. During the coming year the design of the lower sonde (core and screen barrels and cutting head/cutters) will be completed as will the sensor and control electronics design and software development. Assembly and "bench" testing of the actuators and lower sonde are also scheduled for completion. The entire system will be integrated and tested to the extent possible before its shipment to WAIS Divide for use during the 2011-2012 field season.

IDDO suffered a set-back in its development of replacements for outdated motor control modules for the DISC Drill when it was discovered during testing that the design was inadequate and the electronic circuits would have to be re-designed, prototyped, tested, and manufactured. This problem, along with the need to extensively modify drill system sheaves, the need to modify the azimuth measurement system and the resignation of an electrical engineer put a heavy workload on the one remaining electrical engineer. IDDO has contracted an electrical engineer to assist in the tasks.

The unexpected issues with the DISC Drill Development also affected the DISC Drill Replicate Coring System Development Project as resources planned for the project are needed to complete work on the DISC Drill before the 2010-2011 WAIS Divide field season. However, IDDO is confident that the replicate coring system will be ready for first use at WAIS Divide during the 2011-2012 field season.

Replicate coring
In the second quarter FFY2010, design of the "actuated" anti-torques, which will allow the drill to be steered, was completed. IDDO ordered components for the prototype model of the anti-torque actuators and test fixture. A control program was written to allow testing of the mechanical system, and initial testing began. Replicate coring capability for the DISC Drill will be ready beginning with the 2011/12 Antarctic field season.

A new drill for intermediate depth drilling
A white paper justifying the need for an intermediate drill is in preparation by Eric Saltzman, Chair of SAB, and Eric Steig, ICWG representative. Because the new NZ drill (designed from the Danish Hans Tausen drill) may provide an excellent prototype for this drill, detailed science requirements will be developed with the broader community by IDPO-IDDO after results of NZ drill testing at NEEM this coming summer. IDDO engineer Tanner Kuhl will be at NEEM to witness the testing of the NZ drill. This will give an excellent first-person assessment of aspects of the drill that should be replicated and identification of possible problem areas. Opportunities for funding acquisition of a drill are being explored.

Agile drill field projects in Antarctica during January-March included coring on the Amundsen Coast (hand auger plus sidewinder) and Taylor Glacier (hand auger plus sidewinder), and the conclusion of a successful season for the Amundsen Basin seismic project (RAM Drill). While all these field projects were a success, the PIs gave helpful feedback to IDPO and IDDO will continue to develop its drill management procedures to better maintain, repair, and provide science support for all types of drills.

The WAIS Divide Ice Core Project had a successful season with 1,050 meters of high-quality core retrieved and drilling progressing to a total depth of 2,564 meters, only 36 m short of the season's goal in spite of more than a week of delay getting into the site. The problem with hole inclination was corrected in the field, and the drillers were able to reduce inclination from just over 5 degrees to approximately 4 degrees. The new thin kerf core barrel increased core lengths per run from ~2.7 m to 3.3 m.

More information about these projects can be viewed at: https://icedrill.org/fieldwork