ACCESS NUMBER: 30998 TO-10907

STUDY TITLE: Arctic Nearshore Impact Monitoring in the Development Area (ANIMIDA) Program Phase

II - Partitioning of Potential Contaminants between Dissolved and Particulate Phases in Waters of the

Coastal Beaufort Sea

REPORT TITLE: ANIMIDA Task 7 Partitioning of Potential Anthropogenic Chemicals between Dissolved

and Particulate Phases in Arctic Rivers and the Coastal Beaufort Sea

CONTRACT NUMBER: 1435-01-99-CT-30998; TASK ORDER (TO): 10907

SPONSORING OCS REGION: Alaska

APPLICABLE PLANNING AREA: Beaufort Sea

FISCAL YEARS OF PROJECT FUNDING: FY 2000-FY2002

COMPLETION DATE OF REPORT: May 2004

COSTS BY FY: FY 2000: $70,000; FY 2001: $70,000; FY 2002: $19,700

CUMULATIVE PROJECT COST: $159,700

PROJECT MANAGER: John H. Trefry

AFFILIATION: Florida Institute of Technology

ADDRESS: Florida Institute of Technology, Department of Marine & Environmental Systems, 150 West

University Boulevard, Melbourne FL 32901

PRINCIPAL INVESTIGATORS: John H. Trefry and John S. Brown

KEY WORDS: ANIMIDA, nearshore Beaufort Sea, Sagavanirktok River, Colville River, Kuparuk River,

total suspended sediments, dissolved, partitioning, trace metals, Arctic, Alaska, hydrocarbons,

BACKGROUND:

The Arctic Nearshore Impact Monitoring in Development Area (ANIMIDA), a five-year study started in

1999, has provided baseline data and monitoring results for chemical contamination, turbidity, and

subsistence whaling in the vicinity of Northstar and Liberty development sites. Northstar is in State

waters, but includes production of some OCS oil through directional drilling. Liberty, if approved, would

be the first offshore OCS development project in the Beaufort Sea or elsewhere in the Alaska OCS. This

Task Order sought to determine partitioning of potential contaminants between dissolved and particulate

phases in waters in the ANIMIDA study area.

OBJECTIVES:

To (1) determine concentrations of selected metals and organic substances in dissolved and particulate

forms in water of source rivers and the coastal Beaufort Sea, (2) determine partitioning coefficients

(particulate/dissolved) for selected metals and organic substances, and (3) determine the partitioning

between dissolved and particulate phases for polynuclear aromatic hydrocarbons (PAH) in North Slope

crude oil from a laboratory spiking experiment using Beaufort Sea water.

DESCRIPTION:

Concentrations of the following dissolved and particulate metals were determined for the Sagavanirktok,

Kuparuk and Colville rivers and for the coastal Beaufort Sea: arsenic (As), barium (Ba), calcium (Ca),

copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), lead

(Pb) and zinc (Zn), particulate aluminum (Al) and dissolved and particulate organic carbon (DOC and

POC). The underlying theme in this effort was to understand the natural sources, transport pathways and
ACCESS NUMBER: 30998 TO-i 0907

concentrations of dissolved metals in the coastal Beaufort Sea. The natural processes that help regulate

concentrations of dissolved substances must be understood before attempting to identify anthropogenic

perturbations. In the dissolved form, trace metals and organic substances are generally more biologically

available and have a greater chance to induce toxic effects in organisms. In general, concentrations of

dissolved trace metals in coastal seawater are controlled by river runoff, adsorption on suspended

sediment and biological uptake.

Field activities for ANIMIDA Task 7 included sampling of rivers and offshore water during open-water

periods of July-August 2000, 2001 and 2002 pIus through-ice and river break-up efforts during May-June

2001 and 2002. Rivers are a major source of dissolved metals to the study area. The Sagavanirktok

River was sampled daily during June 2001 and 2002 and the other two rivers were sampled every two to

five days as logistics permitted. Samples of water and suspended sediment from the Sagavanirktok River

also were collected at mile 401 on the Dalton Highway, and at the site of a gauging station maintained by

the U.S. Geological Survey (U.S.G.S.), about 100 miles south of Deadhorse.

During the 2001 summer field season, eight 4-L samples of Beaufort Sea water were collected for

analysis of polynuclear aromatic hydrocarbons (PAH). Three samples were collected at sites near

Northstar Island, three were collected at Beaufort Sea Monitoring Program (BSMP) stations, and two

were collected at stations near Liberty Prospect. Eight replicate samples were collected at station 3A.

One of the station 3A replicates was analyzed with the other Beaufort Sea seawater samples. The

remaining seven replicates were used in a spiking study to assess partitioning of potential organic

contaminants between the dissolved and particulate phases.

SIGNIFICANT CONCLUSIONS:

The main conclusions from ANIMIDA Task 7 are as follows:

concentrations of dissolved trace metals and PAH in the study area are very low and

characteristic of pristine water.

a pulse input of dissolved organic carbon and dissolved Fe, Cu, K, Mn, Pb and Zn from rivers

occurs during spring runoff.

concentrations of some metals can be modeled with a simple distribution coefficient.

active physical, chemical and biological processes are at work to create a dynamic, yet

predictable, distribution of dissolved trace metals in the study area.

Such information will be useful for long-term monitoring (years, decades and centuries) and will provide

an evolving capability for predicting impacts from any spills or other releases of chemicals within the

drainage basin or the coastal sea.

STUDY RESULTS:

Concentrations of dissolved trace metals were low, but different among the three rivers. For example, in

the Sagavanirktok River, the following average concentrations of dissolved metals were determined: Pb

at 15 ng/L, Cu at 0.6 pg/L and Ba at 32 pg/L whereas in the Colville River these three metals were found

at concentrations of 60 ng/L, 2 pg/L and 50 pg/L, respectively.

The most striking trend in the dissolved data was found for DOC with maximum levels of DOC in the

Sagavanirktok River >8 mg!L during peak flow relative to 2 mg/L at lower flow. Concentrations of Fe, Mn,

K and Cu followed trends for DOC quite well. These trends are consistent with a pulse of exuded, DOCrich water from thawing soils in the drainage basin that occurred shortly after the initial melt event during

the period of peak flow. Trends for dissolved Fe, Mn and K, also derived from thawing soils, matched the

trend observed for DOC. Concentrations of dissolved Cu followed DOG relatively well; however, the

magnitude of change was somewhat less than observed for the other elements. For dissolved Ba, Ni and

Pb, concentrations shifted only slightly in response to the increase in levels of DOC. Concentrations of

particulate metals (on the basis of pg metal/g suspended sediment) were rather uniform during June 2001
ACCESS NUMBER: 30998 TO-10907

and fit metal/Al ratios defined for bottom sediment in the coastal Beaufort Sea. In most cases, very little

(<10%) of the metal burden of the rivers was in the dissolved phase during the June period of high flow.

The forms of the metals and controls on concentrations of dissolved metals in rivers are important to

understanding subsequent behavior in the saline water of the coastal Beaufort Sea. Concentrations of

dissolved and particulate Ba varied directly among the rivers and thus a simple distribution coefficient (Kd)

was used to explain observed concentrations. When this approach was used for Ba, the fit was quite

good with the Kd for Ba averaging 2.4 ± 0.5 x 1O4 for all the rivers. This trend supports the concept that

concentrations of Ba in suspended sediment regulate concentrations of dissolved Ba. The same

approach also was applied to Pb and Cu; however, the fit was less consistent, suggesting that other

factors, such as complexation with organic matter influences concentrations of dissolved Pb and Cu.

Concentrations of dissolved trace metals in the saline water of the coastal Beaufort Sea were generally

lower than found in the rivers with the following observations: Pb at 4-7 ng/L, Cu at 0.5 pg/L and Ba at 13

pg/L. Concentrations of total Hg in the coastal Beaufort Sea also were low at about 0.5-0.8 ng/L.

Concentrations of As increased from the rivers to the sea and concentrations of Ba decreased.

The Total PAH (TPAH) concentrations in whole seawater samples (dissolved + particulate fractions) were

low and ranged from 22 to 68 ng/L. The TPAH of the particulate fraction of the seawater samples ranged

from 13.2 to 18.5 ng/L. The PAH distribution for the particles shows a petrogenic or petroleum

hydrocarbon composition, characterized by a predominance of the 2- and 3-ringed alkyated PAH

compounds, with a lower abundance of 4-, 5- and 6-ringed PAH. The PAH in the seawater samples were

primarily associated with suspended sediment. The composition of the PAH in the suspended sediment

was similar to that observed for riverine and benthic sediment in the ANIMIDA study area. Analysis of the

dissolved fraction showed no detectable PAH in the dissolved phase in support of the statement that the

PAH are bound to suspended sediment and do not partition to any great extent into the dissolved phase.

STUDY PRODUCTS:

Trefry, J. H.; Rember, R. D.; Trocine, R. P.; and J. S. Brown. 2004. ANIMIDA Task 7 Sources,

Partitioning of Potential Contaminants between Dissolved and Particulate Phases in Waters of the

Coastal Beaufort Sea. OCS Study MMS 2004-031. Final Report 1435-01 -99-CT-30998, TO 10907.

Prepared by Florida Institute of Technology and Battelle for Minerals Management Service Alaska

OCS Region. Anchorage, AK.

Rember, R. D. 2002. "Composition of Dissolved and Suspended Matter Transported by the

Sagavanirktok, Kuparuk and Colville Rivers in the Alaskan Arctic. Ph. D. dissertation. Florida

Institute of Technology.

Rember, R. D.; and J. H. Trefry. 2004. Increased Concentrations of Dissolved Trace Metals and Organic

Carbon during Snowmelt in Rivers of the Alaskan Arctic. Geochimica et Cosmochimica Acta 68: 477-

89.

Rember, R. D.; Trefry, J. H.; and A. P. Trocine. 2003. Riverine Transport & Dispersion of Dissolved

Trace Metals in the Coastal Beaufort Sea. Presented at SETAC 24th Annual Meeting in North

America. Austin, TX: SETAC.

Rember, R. D.; Trefry, J. H.; and R. P. Trocine. 2003. Partitioning of Potential Contaminants between

Dissolved and Particulate Phases. In: Alaska OCS Region Ninth Information Transfer Meeting And

Barrow Information Update Meeting Final Proceedings, OCS Study MMS 2003-42, pp. 24-25.

Prepared by MBC Applied Environmental Sciences. Anchorage, AK.: United States, DOI, MMS,

Alaska OCS Region.

*pls affiliation may be different than that listed for Project Manager(s).
/ I 171. 170 SI. 17*1011 MIL1I 10 0* ItO

00(1110 r 110 JIt

I I 100 Itfl ItO 40 40' ItI

ARCTIC SUBREGION

CHUKCHI SEA

BEAUFORT SEA

ACCESS NUMBER: 30998 TO-i 0907

Focus area for Arctic Nearshore Impact Monitoring in the Development Area (ANIMIDA) Program.