Title : Ice core drilling at McMurdo Dome Type : Antarctic EAM NSF Org: OD / OPP Date : July 28, 1993 File : opp93111 NATIONAL SCIENCE FOUNDATION OFFICE OF POLAR PROGRAMS OFFICE OF THE ENVIRONMENT 202/357-7766 MEMORANDUM Date: July 28, 1993 From: Acting Environmental Officer Subject: Initial Environmental Evaluation (Ice Core Drilling at McMurdo Dome, Antarctica Environmental Impact Assessment and Finding) To: Office Director, Polar Programs Manager, Polar Operations Health and Safety Officer Head, Polar Science Section Manager, Science Projects Program Manager, Glaciology Environmentalist, ASA Refs: The Connection Between Ice Dynamics and Paleoclimate From Ice Cores: A Study of Taylor Dome, Antarctica. Shallow and Deep Ice Coring Devices Developed by the Polar Ice Coring Office. Butyl Acetate, an Alternative Drilling Fluid for Deep Ice Coring Projects, by T. A. Gosink et. al. This Environmental Action Memorandum describes the need for and location of proposed actions to drill an ice core through the McMurdo Dome to bedrock. Scientific study of this ice core should reveal a climate record of the Holocene and the last part of the last glaciation. The Acting Environmental Officer posed a set of questions relating to the proposed project and to the potentially affected environment. These questions were responded to by Dr. Pieter Grootes, University of Washington, S-167, and Baxter Burton, Polar Ice Coring Office on July 23, 1993, the Acting Environmental Officer received the requested assessment. Questions and responses are shown below: Environmental Assessment Queries and Responses General 1. What is the specific purpose of the proposed activity? The purpose of this activity is to retrieve a 700 meter ice core through the entire depth of the McMurdo Dome ice cap into bedrock. From this ice core, a multiparameter paleoenvironmental record of this area will be obtained. What alternatives to the proposed activity have the program and the contractor considered? No action Hand Auger Four Inch Drill 5.2 Inch Drill Hot Water Drill Have probable impacts of all alternatives been considered by the Program and the Contractor? Please explain how. No action. This alternative is would produce no ice and therefore no scientific measurements could be performed. Therefore, the "no action" alternative was not considered. Hand Auger: This drill system cannot penetrate deeper than 50 meters. This would not be sufficient core to make the necessary scientific studies or justify the cost of the project. Four Inch Drill: This system can only drill in a dry hole to a depth of 300 meters which is insufficient depth to reach the underlying bedrock. In addition, the core quality deteriorates after about 200m, depending on ice temperature. 5.2 Inch Drill: This drill has successfully operated in central Greenland at the Greenland Ice Sheet Project (GISP II). It operates in a fluid-filled hole. The drill's depth is limited only by the length of the cable used to lower it into the hole. The drilling fluid used at GISP II is n-Butyl Acetate. Butyl Acetate, an Alternative Drilling Fluid for Deep Ice Coring Projects, by T. A. Gosink et. al., describes the requirements for an ice drilling fluid, what fluids meet these criteria, and why n-butyl acetate was chosen other, less environmentally preferable drilling fluids. Hot Water Drill: Although this drill system will reach the base of the ice and allow for the retrieval of till and rock, it will not produce an ice core. Therefore, this drill system negates the reason for the project. The only practical drill system available which will accomplish the goals of the project is the use of the 5.2 inch drill in a fluid-filled hole. The type of drilling fluid, n-butyl acetate, has been determined to be the safest and most environmentally benign. Should the chosen alternative involve potential impacts, how should these impacts be mitigated by the program or the contractor? There are a number of potential impacts for the chosen alternative. Fabrication of the camp and the drilling rig will require heavy construction activity in the early part of the 1993 field season. All construction waste and debris will be removed from the site while under construction. The impact of solid waste generated by construction workers would be mitigated by managing the waste in accordance with U.S. Antarctic Program (USAP) waste management practices that call for waste minimization and recycling. At the end of the season, the camp and drill rig will be removed and retrograded to McMurdo Station. The effect of extra fuel use may be mitigated by on-going improvements to the fuel storage system to reduce and detect leaks. The borehole, with fluid, will remain for future logging for temperature and other scientific studies. Drifting and blowing snow will quickly eliminate any impacts from the camp. Approximately 700 meters of ice, 5.2 inches in diameter, will be removed from the borehole and flown to McMurdo Station for preliminary scientific study. The ice core will be flown to the National Ice Repository in Denver, Colorado for continued study and archived there. One of the reasons to conduct the preliminary study at McMurdo, rather than onsite, is to reduce the population impact at McMurdo Dome (approximately 15 less people). This reduction will result in a corresponding reduction of airlift, food waste, and services needed at camp. The drilling fluid will be left in hole because the hole it would close from the resulting pressure. Leaving the fluid in the hole preserves the hole for further scientific work. It is estimated that it would take centuries before the n-butyl acetate will enter the ocean by means of glacial movement and well before the n-butyl acetate will have evaporated or disintegrated its components of biodegradable acetic acid and n-butanol,which are both benign chemicals. This drill creates ice chips as it cuts the core from the glacier. These chips are collected on a screen inside the drill and removed on the surface. The chips are centrifuged to remove the butyl. The collected n-butyl-acetate is then returned to the hole and the chips are collected by the science crew and used for further study. Standard equipment for the drill rig is a catch basin which is installed beneath the carousel. It serves to recover most of the drips from the cable and drill when they are hanging on the tower. A drip pan will be installed beneath the 1,000 meter winch drum during modifications to the winch itself. Every effort is made to capture and recycle n-butyl acetate because it is quite an expensive commodity. Usually are cycle figure of about 90 percent is achieved through centrifuging the ice chips. This can vary significantly with conditions, most notably high wind. In this case, a larger percentage of n-butyl acetate is blown off the cable and drill as it hangs on the tower. There is no way to recover this loss or mitigate the effects with a 100 foot tower. A squeegee is used at the borehole casing exit to wipe as much n-butyl acetate off the cable as possible as the drill is being retrieved. After the drill is clear of then-butyl acetate, but still in the casing, it is allowed to hang for a few minutes to allow as much n-butyl acetate as possible to drip off the drill and fall back down the borehole. Due to the variability of conditions, an n-butyl acetate cost savings based on recycling is very difficult to predict. Comparisons with GISP 2 would not be accurate because an apparent n-butyl acetate leak developed in the deeply buried auger system sometime during the past two seasons. Due to the depth at which the auger was buried, it could not be readily retrieved for inspection and repair. This leak was thought to have deteriorated during these two seasons. Therefore no valid comparison can be made between wind blown n-butyl acetate losses and the auger leak with respect to the GISP 2 project. Correlations with GISP 2 weather data would also be needed. During the first season-long drilling effort at GISP 2 in 1991, weather was comparatively good, there was no apparent auger leak, and n-butyl acetate recovery exceeded 90 percent. There is always the potential for spills from n-butyl-acetate, glycol, oils, mogas and diesel in camp. If n-butyl-acetate is spilled, it evaporates quickly. Generators are required for power for the drill and light. Based on our experience in Greenland with this drill, we are knowledgeable about the amount of power required to operate this drill and hence, we are requesting only enough power required to keep the fuel usage and resulting exhaust to a minimum. The Contractor is experienced in Antarctic operations and has used our power requirements to properly size the generator needed. Fuels, oils and lubricants; PICO and the science personnel will comply with any guidelines provided by the contractor for the proper handling of oils and lubricants. This will include any leaks or spills in and around the drill site. (2) PICO will in most cases be handling fuel or hydrocarbon wastes at all for the drill rig. The entire system will be electric and will need only power from the generators. The camp, vehicles and generators will be operated and maintained by ASA. However, we are familiar with USAP procedures and will be following them. The Contractor, science team. and the drill crew will all be using snow mobiles to assist in field operations. This use has been coordinated between the users to minimize the overall impact. Human presence; food, wastes, gray water: There are a standard set of protocols established by the Contractor for all support of remote camps in Antarctica and PICO and the science personnel will comply with these protocols. Have measures to assess the indirect costs of the proposed activity been identified or considered by the program or the contractor? Please explain how. The indirect costs of the coring project are difficult to quantify because science projects will continue at the site, some related to the drilling and some unrelated. The snow accumulation and wind will eliminate most of the evidence of the drilling over several seasons. However, the continuation of borehole measurements and other glacial measurements will require continued human presence which will be funded under future NSF grants. Land Use and Planning 2. Where would the proposed activity be located, specifically? 77 degrees 47 minutes 30 seconds South, 158 degrees 49 minutes 40 seconds, East; Elevation 2400 m. Have alternative locations been considered by the program to the contractor? If yes, which are they; if no, explain why. This area was studied in a 20km by 40km grid to determine the best location for this project. See map in attachment 1. 3. How would any aesthetic impacts to the area from the proposed activity be handled by the Program or the Contractor? There will be no lasting impact because all structures will be removed at the end of the season and retrograded to McMurdo in the 1993-1994 or 1994-1995 field season. 4. Would the proposed activity have any other indirect impacts on the environment? If yes, what are they; if no, explain why none are expected. The drilling and the presence of a camp will create a local source of pollutants, although all care will be taken to minimize this. This will affect a limited area in the immediate vicinity of the drill camp. There are, however, no nearby projects that could be affected. The pollution will cease with the end of the season. Other potential indirect impacts could stem from the following: Fuels and Oils use Generators Garbage Human Impact LC-130 flights These items were discussed in question 1 and will be addressed again in question 7. 5. Would the proposed activity change the traditional use of the proposed (or chosen) site? If yes, how; if no, why? Yes, on a temporary basis. There is no traditional use of the site because it is a remote area on a barren ice sheet, but drilling a 700 meter core could result in future borehole logging studies. However, when these studies are completed, the site will return to its previous state. During the 1994-95 season, one experiment requires the installation of baffling material in the borehole to help stabilize the temperature gradient during logging. This material will be made from a high density polyethylene plastic, commonly known as Drisco pipe, that is non-reactive to n-butyl acetate. It is anticipated that the pipe will remain in the hole due to its depth. 6. Are the physical and environmental characteristics of the neighboring environment suitable for the proposed activity? If yes, explain why; if no,explain why. Yes. Required is a site on the ice divide of a local ice outflow center with regular snow accumulation and a relatively flat bedrock. Maximum summer temperatures should be below -10o C to prevent melting at crystal surfaces. All these criteria are met at the chosen site. Impact and Pollution Potential and Environmental Management: 7. How has protection of the environment and human health from unnecessary pollution or impact been considered for the proposed activity (includes such considerations as pollution abatement or mitigation, and waste management [e.g., of materials, construction wastes])? The choice of n-butyl-acetate as a drilling fluid was selected because it is environmentally benign and will best protect human health and the environment. Protective clothing and respirators will be worn to increase the protection of the workers. The design of the drill and the safety measures and procedures for its operation have been developed by PICO. Waste oils will be collected and retrograded to McMurdo. Camp garbage and human and construction waste will be collected and retrograded. Recyclable materials will be segregated and placed in the appropriately labeled containers for retrograde. All of theses measures have been adhered to in our past camp activities. The Contractor's protocols on human waste and gray water will be followed. 8. Would the proposed activity change ambient air quality at the proposed chosen) site? If yes, how; if no, why. Yes, temporarily and to a small degree. The major activity will occur during the 1993-94 season with a number of LC-130 and Twin Otter flights into and out of the site. The camp will also have the largest number of participants this season. This presence will sharply decrease after this season, but will not entirely disappear. This reduced science presence will translate to a reduction in flights, fuels, generators, human wastes, etc. When activities terminate, conditions will return to "natural" in a few years. 9. Would the proposed activity change water quality or flow (drainage), at the proposed (or chosen) site? If yes, how; if no, why. No. There are no drainage sites at this location, only snow accumulation. 10. Would the proposed activity change waste generation or management at the proposed (or chosen) site? If yes, how; if no, why. Because this location is uninhabited, human activity in this location will require planning for waste generation and management. All non-hazardous waste will be handled according to USAP policies. Hazardous wastes will be stored in accordance with USAP policies and regulations until it can be inspected, properly packaged and retrograded. 11. Would the proposed activity change energy production or demand, personnel and life support, or transportation requirements at the site? If yes, how; if no, why. This is an uninhabited region and therefore, the energy, personnel,and life support requirements will all change or increase during the life of the project. Over the next few years, there will continue to be a scientific presence at this site but it will be considerably reduced than during the 1993-94 season. 12. Is the proposed activity expected to adversely affect scientific studies of locations of research interest (near and distant, in the short-term and in the long term)? If yes, how; if no, why. No; there are no research locations nearby. In the long term, the site will be abandoned and allowed to return to its natural state. 13. Would the proposed activity generate pollutants that might affect terrestrial, marine or freshwater ecosystems within the environs of the station or inland camp? If yes, how; if no, why. No. There is no life on the ice sheet. The only material that will remain is n-butyl acetate which is needed to provide the hydrostatic pressure to keep the drill hole open for future ice flow research. The n-butyl acetate is well enclosed in the hole and if any should be released, it does not provide a hazard. It rapidly biodegrades to acetic acid and n-butanol, both benign chemicals. 14.Does the site of the proposed activity serve as habitat for any significant assemblages of Antarctic wildlife (for example, mosses or lichens, or antarctic birds or marine mammals)? No. Human Values 15. Would the proposed activity encroach upon any historical property of the site? If yes, how; if no, why. No. There are none. Other Environmental Considerations 16. What other environmental considerations may be potentially affected by the proposed activity at the proposed (or chosen) site? For example,have impacts associated with decommissioning of the activity been considered (and how). This is activity is planned for a single season drilling operation with all drill activities will be decommissioned and retrograded prior to the end of the season. Therefore, this activity is included in the plan for the project. Only low intensity scientific studies will continue in future seasons. Occupational Safety and Health Concerns 17. What occupational safety and health related issues may have to be addressed during this activity (*for example, Occupational Safety and Health Administration (OSHA) standards [29 CFR 1910], other consensus standards)? If none, explain why. Rotating machinery Snowmobiles Exposure to fuels, oils and n-Butyl Acetate What steps would be taken to eliminate any problems, risks or hazards associated with those issues? Explain fully. The drill to be used on this project is heavy industrial equipment. It has rotating parts, sharp metal pieces and a number of pinch points. Over the last five years this drill as been in use at GISP II, we have developed a set of safety protocols, based on OSHA standards, that have allowed us to operate almost injury free. Safety is our number one concern, and the protocols are designed to insure that personnel and moving parts remain separated. Operation of the snowmobiles will conform to guidelines issued by the USAP to minimize the chance of injury. To avoid exposure to n-butyl acetate, the drillers wear rain suits (pants and hooded jackets) with boots and gloves. Additionally, they will wear a respirator. PICO maintains an n-butyl acetate monitoring system in the drilling area. In five years at GISP II, this monitor has never reached the minimum level where the rain suits are required. Finally, there will be an emergency shower at the drill area in case of unprotected exposure to n-butyl acetate. As to exposure to other chemicals at the site, all drill and scientific personnel will follow the guidelines and regulations of USAP. All of the drillers wear tight cuff n-butyl acetate-resistant "wet gear" over their extremely cold weather gear as well as gloves, hoods and chemical vapor respirators. This prevents most but not all dermal contact with n-butyl acetate. The extent of dermal contact is not a readily measured quantity and depends on the type of activity and care taken by the individual. 18. Are staff or participants aware of the potential safety and health issues or problems; and, are they prepared to deal with them effectively?If yes, explain how. If no, why not? Yes. PICO has a commitment from six of the drillers presently working on the same drill in Greenland to go to Antarctica for this project. These individuals will be fully versed in all safety matters. Any replacement drillers we hire are started in the least dangerous positions after a full and complete indoctrination into the operation of the drill and all safety procedures. All other personnel are kept a safe distance from the drill and its moving parts. The science party has five members with field experience in Greenland and Antarctica, and with ice core drilling and processing experience. New members will be trained. A safety protocol manual for GISP 2 is not complete at this time. This is due partly to the fact that technical development and final configuration of the drill system has only recently been completed. It is also due to the fact that the field engineer responsible has not had sufficient time out of the field and away from drill development activities to complete the written document. This field engineer is the designated safety officer for all 13.2 cm drilling activities and he will be onsite for the McMurdo Dome Project. Little time is available between the time this field engineer returns from GISP 2 and his scheduled deployment to Antarctica. The written protocol is expected to be completed later this year. On-site training will be provided for drillers unfamiliar with the drill system but presently only 2-3 drillers will be new and they may have experience from prior years. Will know better after we have completed hiring. Typical n-butyl acetate vapor level readings within the drill dome at GISP 2 were in the 20 to 50 PPM range. Again, this varied somewhat with conditions and time.Exact data on n-butyl acetate vapor levels in the dome (including the 1993 GISP 2 season) is not yet available. It is a new form on disk and must be finished. The information will be forwarded as it becomes available. Winds in excess of 48 kph usually dictate that drilling activities cease. This is due principally to wind movement of the drill as it hangs on the tower which causes making and breaking connections to be difficult. Drilling ceases until conditions improve. Standard work shifts are 12 hours in length. A multi-section Jamesway or Weatherport will be provided by ASA near the drill site as a combination warm-up shack, changing room and work shop. Design of the camp layout is being done by ASA. They are still completing the details of science trenches, generator location, etc. A proposed site plan of the Mcmurdo Dome environs should come from them. 19. Identify all potentially hazardous materials, chemicals, or equipment that are proposed for use (for example, drilling fluids, and pressure vessels)? The regular camp fuels are JP-8, Mogas, and Coleman fuel, generator oil and snowmobile oil. Wet batteries used on site contain sulfuric acid and lead sulfate. For drilling n-butyl acetate, glycol, and ethanol will be on-site. Ethanol is also used in a cold trap for vapor sampling. Small quantities of dimethylphtalate and isooctane will be used for thin sections and density measurements by physical properties researchers. Small quantities of hydrochloric acid and beryllium (Be) carrier solution will be used in Be chemistry. Cleaning fluids will be use in the kitchen. Finding The Acting Environmental Officer, after reviewing the information presented above, believes that the proposed activity poses neither potentially minor nor transitory impacts to the antarctic environment within or near McMurdo Dome. There are recognized scientific benefits from extracting a deep ice core and in conducting future borehole logging activities in the open hole. However, before the project can proceed, a Standard Operating Procedure (SOP) must be completed, reviewed, and approved by OPP's Health and Safety Officer. The Principal Investigator, Contractor and Program are authorized to proceed with the proposed activity after approval of the SOP. Jane Dionne cc: Chairperson, NSF Committee on Environmental Matters Dr. Pieter Grootes Mr. Baxter Burton