Progress Report for the Period: October 15, 2008 to April 15, 2009

Principal Investigators: Dr. Liv-Guri Faksness, Dr. Odd Gunnar Brakstad, Dr. Mark Reed, and Frode Leirvik


Introduction:
The project is split into three main activities:
1. Behavior (transport and physical fate) of oil hydrocarbons in ice;
2. Biodegradation of crude oil hydrocarbons in ice, with focus on the brine channels/inclusions; and
3. Modeling of behavior and biodegradation of crude oil hydrocarbons in ice (prototype model)

Accomplishments since project initiation:

Scheduled Tasks:
A1. Transport and behavior
Establishment of laboratory equipment for ice core freezing and testing and establishment of freezing and thawing cycles/times with different temperature regimes.
A2. Biodegradation
Initial testing and start of biodegradation experiment 1 (BE1)
A3. Modeling
Complete model software development at UA Fairbanks; deliver software to SINTEF for integration into broad scale ice model

Progress and prelminary data on these Tasks:
B1. Transport and physical fate of oil hydrocarbons in ice
A setup with a series of 8 columns for ice core freezing is established. The columns are constructed to simulate the freezing of first year sea-ice to quantify changes in dissolved oil component concentrations over time through freezing and thawing cycles. Natural seawater is used.

The columns are made of 80 cm polycarbonate cylinders with an inner diameter of 144 mm. Each column is placed in a Styrofoam box and the void between the box and the column is filled with insulating padding. The system is placed in a temperature controlled room at -22°C. The ice growth is monitored closely in one of the columns by thermistor strings positioned at every 5th cm in the ice for temperature readings during the experiments.

Figure 1 Column design and freezing and melting procedure

In initial experiments 20 cm of ice were frozen in approximately 56 hours. As thicker ice will be used a freezing time of in excess of a week may be necessary. The ice formed in the initial experiments was microtomed and photographed. As shown in Figure 2 large crystals are growing vertically from the surface down. This is a crystal structure that favors the latter formation of brine channels.

To simulate spring thawing, the temperature above the ice is controlled at a higher temperature to enhance the size of the brine channels. The time needed to warm up the entire column of frozen ice is strongly dependent on the temperature above the ice. The initial experiments indicate that several weeks may be needed to heat the entire ice core without overheating the upper layers.


B2. Biodegradation
The Biodegradation Experiment #1 (BE1) was started in January 2009. The objectives of this experiment was investigate the potential for crude oil hydrocarbon (HC) biodegradation at two different subzero temperatures, -5 and -10°C over a period of 6 months, with artificially generated salinity conditions of marine ice brine channels at these temperatures (100 PSU at -5°C) and 150 PSU at -10°C). A crude (fresh) Statfjord paraffinic oil was used as HC source, either as thin oil films immobilised on hydrophobic adsorbents (Fluortex febrics) or as water-soluble fractions (WSF) with oil-seawater (O/W) ratios of 1:1000 or 1:10,000. Normal surface seawater was used as microbial inoculum. The correct salinities were achieved by adding synthetic marine salts (Sigma) to the seawater until correct salinities for the two temperatures. Initial studies were conducted to find an artificial seawater salt which resembled the salt composition of natural sea ice brines generated at -5 and -10°C: Reference experiments were conducted at 0 and +5°C in normal seawater.  The setup and sampling regimes are described in Table 1.

The experiment was started in January, and by the end of March samples from 0, 1, 2, 4 and 8 weeks were collected for chemical and microbiology analyses.

Chemical analyses included GC-FID analyses of immobilised oil (C17/Pristane and C18/Phytane ratios) and GCMS analyses of WSFs. Microbiological analyses included microscopic counts of bacteria-like particles, Most-probable number (MPN) counts of viable heterotrophic and oil-degrading bacteria in WSFs, and PCR-DGGE analyses of immobilised oil and WSFs to characterise the changes in microbial communities during the experiments.


Table 1. Experimental setup for biodegradation experiments BE1, with oil/water (O/W) ratios of 1/1000 and 1/10000. Sterile controls (St) were included to correct for abiotic degaradtion

Results January – March 2009
Collected samples have so far been analysed by GC-FID analyses of immobilised oil, and by microscopic and MPN counts of WSFs. Some results are presented below.

Figure 3. Ratio between n-C17 and Pristane of oil film samples extracted from Fluortex fabrics and analyses on GC-FID

Figure 4. Microscopic counts with the fluorescent stain DAPI of the original seawater (week 0) and WSF-samples after 4 and 8 weeks. Results are shown for WSFs with O/W ratios of 1:1000 and 1:10,000, and incubated at -5, 0, or -5°C

Results after 8 weeks showed that no biodegradation was observed at subzero temperatures in the oil films. For the WSFs bacterial growth seemed to be stimulated at all temperatures, with the highest responses at 0°C. Increases in bacterial concentrations were also observed in the WSFs incubated at -5°C. However, no chemical analyses have so far been recorded in these samples.

B3. Modeling
The software remains under development at the University of Alaska Fairbanks. Chris Petrich is simplifying and clarifying the code for eventual transfer to SINTEF. Some effort has gone into meetings, planning and design considerations, and replacement of a doctoral student to carry out the integration into a regional scale ice model. We have identified a Danish researcher at SINTEF offices inn Stavanger who is interested in taking on this task.

Time is of the essence, since the integration work is also non-trivial. We are therefore hoping to receive the working code within a short time.

Manuscripts, Reports, Presentations
None

Personnel
Hours between September 15, 2008 and April 15, 2009.

Person	Hours	Task
Transport and behavior
Liv-Guri Faksness	34	Project admin, planning and meetings
Per Johan Brandvik	21	Establish lab equip, meetings
Frode Leirvik	158	Establish and run lab equip, thin section analysis
Bror Johansen	24	Establish lab equipment
Ragnhild L. Daaae	15.5	Thin section analysis
Jomar Finseth	8	Thin section analysis
Biodegradation
Odd Gunnar Brakstad	21	Meetings and planning
Kristin Bonaunet	71	Lab analysis
Max Frenzel	25.5	Lab analysis
Siv-Hege Vang	55.5	Lab analysis
Inger B. Steinsvik	12	Lab analysis
Modeling
Mark Reed	16	Meetings and planning

Tasks for the Next Detailed Reporting Period:

Tasks and Activities for Next Reporting Period to Meet Project Objectives.
A1. Transport and behavior
Implement application method for oil and sampling techniques.
Initial testing of SPMEs (insertion and sampling)
Initiate the experiments described in Table 3 in the proposal (Comparison of different sampling techniques).

A2. Biodegradation
Finish BE 1: Samples will be collected according to the plans shown in Table 1 Planning of biodegradation experiment 2 (BE2): A preliminary outline of this experiment has been presented in the proposal, but may be changed, depending on the results from BE1. Irrespective of the BE1 results efforts will be made in BE2 to study initial potentials for bioremediation of oil in marine ice, introducing fertilizer mixtures at subzero temperatures in the artificial brines.

A3. Modeling
Receipt of code from UAF; begin detailed design and implementation in larger scale regional model.

Concerns or Difficulties Anticipated:
None.

Schedule:
According to the contract is the project period from September 1, 2008 to August 31, 2010.

Original timeline (from proposal):



Updated timeline: