Arctic Nearshore Impact Monitoring in Development Area III (Animida): Contaminants, Sources, and Bioaccumulation; Executive Summary

Branch: Executive

Category: Executive Agency Publications

SuDoc Class Number: I 72.

Government Author: Interior Department, Bureau of Ocean Energy Management

Personal Author: Kasper J; Dunton KH; Schonberg SV; Trefry J; Bluhm B; Durell G; Wisdom S; Blank J

Series Title: BOEM Environmental Studies

Publication Title: Arctic Nearshore Impact Monitoring in Development Area III (Animida): Contaminants, Sources, and Bioaccumulation; Executive Summary

Date Issued: 2017

Subject: Anthropogenic Properties
Marine Benthic Communities;Water Quality
Heavy metals; contaminants; bioaccumulation; Colville River; Kuparuk River; Sagavanirktok River

Obligation Number: M13PC00019

Geographic Scope: Alaska

Report Number: BOEM 2017-032

CSE Reference: Kasper J, Dunton KH, Schonberg SV, Trefry J, Bluhm B, Durell G, Wisdom S, Blank J (Olgoonik Fairweather, LLC, Anchorage, AK). 2017. Arctic Nearshore Impact Monitoring in Development Area III (ANIMIDA): contaminants, sources, and bioaccumulation; technical summary. Anchorage (AK): US Department of the Interior, Bureau of Ocean Energy Management. 9 p. Obligation No.: M13PC00019. Report No.: OCS Study BOEM 2017-032. URL: https://espis.boem.gov/Final%20Reports/BOEM_2017-032ES.pdf

Abstract: The Arctic Nearshore Impact Monitoring in Development Area III (ANIMIDA III) Project was designed to update baseline information from previous BOEM environmental studies, including: (1) the Beaufort Sea Monitoring Program (BSMP, 1984–1989), (2) the ANIMIDA Project (1999–2002), and (3) the continuation of the Arctic Nearshore Impact Monitoring in the Drilling Area (cANIMIDA) Project (2004–2007), relevant to offshore oil and gas exploration and production in the coastal Beaufort Sea. Sampling was undertaken during the open-water periods in 2014 and 2015 (late July through early August in both years) and during the 2015 spring-freshet to describe: (1) physical oceanography, (2) the distributions of trace metals in bottom sediments, suspended sediments, and biota, (3) the characteristics of petroleum hydrocarbons in the sediments and benthic organisms, (4) benthic infauna, carbon resources, and trophic structure, and (5) epibenthic communities and demersal fish communities in the central portion of the U.S. Beaufort Sea. Nearshore physical oceanography was significantly influenced by seasonally dependent freshwater input from rivers that freeze in the winter, wind driven upwelling/downwelling, coastal currents/jets, vertical stratification, sea ice, and gravity currents. Concentrations of 17 trace metals were measured from bottom sediments, suspended sediments and biota collected across the region to detect gradients and point anomalies in trace metals, and to infer processes driving these concentrations such as diagenetic remobilization, sorption, scavenging, and bioaccumulation. Hydrocarbons (polycyclic aromatic hydrocarbons [PAH], saturated hydrocarbons [SHC], and sterane and triterpene [S/T] petroleum biomarkers) were measured in sediment and marine animal samples collected from the nearshore to the offshore and reflect background levels that are well below concentrations that could cause toxic effects. A quantitative assessment of the biomass, abundance, and community structure of benthic populations of the Beaufort Sea Shelf along with a detailed characterization of food web dynamics documented a benthic species inventory of 353 taxa collected from 126 individual van Veen grab samples (0.1 meters squared [m2]) at 42 stations, and identified three hotspots in mid-shelf locations in the western Beaufort in Harrison Bay, the central Beaufort, including Stefansson Sound, and the eastern Beaufort from Barter Island east to Icy Reef. Explanatory factors include a deposited sediment pool that includes ice algae, bacteria, and other benthic microalgae, as well as a regional gradient of terrestrial carbon in Beaufort Sea food webs indicated from δ13C measurements. Distributions of epibenthic invertebrates and demersal fish communities reflect the physically dynamic nature of the Beaufort Sea shelf, characterized by strong land-ocean interactions in its nearshore zone, and corresponding to signatures from oceanic water masses. This study extends an important baseline for oil and gas interests in this regions, documenting concentrations of metals and hydrocarbons found in sediments and biota that are introduced naturally by river runoff and coastal erosion.