NINA Minirapport 519 Environmental monitoring program for the Ormen Lange Onshore Processing Plant at Nyhamna, Gossa Vegetation and soil - annual report 2014 Per Arild Aarrestad Vegar Bakkestuen NINA Minirapport 519 Aarrestad. P.A. & Bakkestuen, V. 2014. Environmental monitoring program for the Ormen Lange Onshore Processing Plant at Ny- hamna, Gossa. Vegetation and soil - annual report 2014. - NINA Minirapport 519. 26 pp. Trondheim, November 2014 OWNER OF COPYWRIGHT © Norwegian Institute for Nature Research ACESSIBILITY Unpublished PUBLISERINGSTYPE Digital document (pdf) RESPONSIBLE SIGNATURE Per Arild Aarrestad (sign.) CONTRACTOR A/S Norske Shell CONTACT PERSON - CONTRACTOR Siv Kristoffersen COVER PICTURE Rubus chamaemorus. Photo: P.A. Aarrestad KEY WORDS Gossa, Aukra, Fræna, Møre & Romsdal County, oil industry, process plant, environmental monitoring, plant growth, bog moss, peat water, peat soil, heavy metals, nitrogen, eutrophica- tion. 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KONTAKTOPPLYSNINGER NINA hovedkontor NINA Oslo NINA Tromsø NINA Lillehammer Postboks 5685 Sluppen Gaustadalléen 21 Framsenteret Fakkelgården 7485 Trondheim 0349 Oslo 9296 Tromsø 2624 Lillehammer Telefon: 73 80 14 00 Telefon: 73 80 14 00 Telefon: 77 75 04 00 Telefon: 73 80 14 00 www.nina.no 2 NINA Minirapport 519 Content Content ........................................................................................... 3 1 Introduction ............................................................................... 4 2 Maintenance of the monitoring localities in 2014 ................. 6 3 Plant growth of red bog moss ................................................. 6 3.1 Methods ................................................................................ 6 3.2 Results .................................................................................. 6 4 Chemical characteristics of peat water .................................. 7 4.1 Methods ................................................................................ 7 4.2 Results .................................................................................. 8 5 Chemical characteristics of peat humus ............................. 14 5.1 Methods .............................................................................. 14 5.2 Results ................................................................................ 15 6 Discussion and conclusion ................................................... 18 6.1 Plant growth ........................................................................ 18 6.2 Chemical content of peat water .......................................... 18 6.3 Chemical content of peat humus ........................................ 19 6.4 Main conclusion .................................................................. 19 7 References .............................................................................. 21 8 Attachments ............................................................................ 22 3 NINA Minirapport 519 1 Introduction The Ormen Lange Onshore Processing Plant on the island Gossa in Aukra municipality receives unprocessed gas and condensate from The Ormen Lange field in the Norwegian Sea. During the processing of sales gas and condensate the plant emits CO, CO2, NOx, CH4, NMVOC (inclusive BTEX), SO2 and small amounts of heavy metals as specified in the discharge permit issued by the The Norwegian Environment Agency. The plant was put into operation in 2007 with A/S Norske Shell as the operator. Due to technical challenges, the emission of NOx is higher than expected ac- cording to originally design. In 2008 A/S Norske Shell initiated an environmental monitoring programme related to possible ef- fects from emissions to air on vulnerable habitats (Aarrestad et al. 2009). Two monitoring localities were established, one with potentially relatively high N-depositions north of the plant at Gule-Sta- vikmyran Nature Reserve in Fræna municipality (locality Gulmyran) and one to the south on the is- land Gossa with less deposition (locality Aukra) (McInnes et al. 2008) (Figure 1). Figure 1. Map of the monitoring localities Aukra and Gulmyran. The Ormen Lange Processing Plant is situated at Nyhamna. The monitoring program integrates analyses in permanent plots of species composition of ground vegetation, plant growth and chemical contents of soil, peat humus, peat water and plants in two different habitats, 1) wet oligotrophic heathland and 2) raised bogs, including hummocks and lawns. The baseline study for the monitoring project was carried out by NINA in 2008 (Aarrestad et al. 2009). A full re-analysis was carried out in 2010 (Aarrestad et al. 2011), and a new re-analysis is 4 NINA Minirapport 519 planned in 2015. Maintenance of the monitoring localities and measurements of plant growth of red bog moss (Sphagnum capillifolium) have been carried out each year from 2009 to 2014 (Aarrestad & Bakkestuen 2009, 2012; Aarrestad et al. 2013, 2014). In 2012 the yearly analyses were expanded to cover chemical analyses of peat humus and peat water, using the same methods as done in the full analyses in 2008 and 2010. In 2013 the number of replicates of plant growth measurements of red bog moss and chemical analyses of peat water were extended to meet the requirement for more reliable statistical analyses. In addition plant avail- able nitrogen (ammonium and nitrate) in peat humus were analysed. This report sums up the results from the yearly analyses from 2008 to 2014, related to the plant growth study of red bog moss (Sphagnum capillifolium) and the chemical analyses of peat water and peat humus. Changes in monitored variables are discussed. Values of measured variables in 2014 are attached. 5 NINA Minirapport 519 2 Maintenance of the monitoring localities in 2014 The permanent marking of the plots was, as earlier years, much more affected by deer at Aukra than at Gulmyran, indicating a higher deer population at Aukra. Damaged and missing markers were replaced. The vegetation within the permanent plots for analyses of species composition was not disturbed. 3 Plant growth of red bog moss 3.1 Methods In 2008 twenty individuals of the red bog moss (Sphagnum capillifolium) were marked for repeated measurements of plant growth at both localities (Figure 2). The individuals were marked with a pin on the ground and the plant growth was measured by the “crancked wire” method (for detailed methods see Aarrestad et al. 2009). Each year some plots are lost due to trampling by animals, and new plots have been established. In 2013 five new individuals were marked on each locality, mak- ing a number of 25 individuals per locality for reanalyses in 2014. Figure 2. Measurements of plant growth of red bog moss (Sphagnum capillifolium), with bended steel wire. 3.2 Results There was a significant decrease in average length growth of the bog moss (Sphagnum capilli- folium) from 2008 to 2013 at both localities (p = 0.002, two-way ANOVA), but no significant differ- ences between the localities (Figure 3). However, there is a small trend that the average yearly growth from 2008 to 2014 was slightly higher at Aukra than at Gulmyran, 0.75 cm and 0.67 cm re- spectively. In 2014 the average growth increased on both localities, 0.72 cm and 0.79 cm respec- tively. 6 NINA Minirapport 519 Sphagnum capillifolium 1,6 1,4 1,2 2008‐2009 1 2009‐2010 0,8 2010‐2011 cm 0,6 2011‐2012 0,4 2012‐2013 0,2 2013‐2014 0 Aukra Gulmyran Figure 3. Average yearly growth of red bog moss (Sphagnum capillifolium) from 2008 to 2014 at the two monitoring localities Aukra and Gulmyran, with standard deviation. (Aukra 2008 - 2009: n = 16, 2009 - 2010: n = 16, 2010 - 2011: n = 14, 2011 - 2012: n = 15, 2012 - 2013: n = 14, 2013 - 2014: n = 21.Gulmyran 2008 - 2009: n = 17, 2009 - 2010: n = 19, 2010 - 2011: n = 19, 2011 - 2012: n = 17, 2012 - 2013: n = 18, 2013 - 2014 n = 23. 4 Chemical characteristics of peat water 4.1 Methods Five peat water samples were collected from pools in 2008, 10 samples in 2010 and 2012 and 15 samples in 2013 and 2014 at both localities (Figure 4). Figure 4. Site for vegetation analysis and sampling of peat water at Gulmyran, 7 NINA Minirapport 519 The samples were collected from the same pools as previous years, except in 2012 when some plots were drained out, due to a long period with low precipitation in front of the sampling. New samples were then taken from the nearest pool of the original pool. The samples were analysed for water + conductivity, pH, elements, nitrogen (N) as ammonium-N (NH4 -N) and total N, according to methods in Ogner et al. (1999) at the Norwegian Institute for Forest and Landscape. The heavy metals lead (Pb), nickel (Ni), cupper (Cu) and zinc (Zn) were measured at The Norwegian Institute for Air Research (NILU) according to the NILU-U-100 method, and mercury (Hg) by use of the NILU-U-60 method (Aarrestad et al. 2009). In 2008 and 2010 the samples of Hg were analysed with CV-AFS technique, and in 2012, 2013 and 2014 with ICP-MS technique. 4.2 Results Conductivity of peat water The average conductivity of peat water has increased from 2008