Life cycle assessment of a clean-up operation

The concrete mitigation strategy that is assessed further here is the clean-up of remote arctic beaches by hand. The example taken here is a one-week arctic boat expedition with about 120 participants that was launched in summer 2015 to collect beach trash at the Norwegian archipelago of Svalbard, far away from the mainland and long behind the Arctic Circle (AECO, 2014). 

The focus of the LCA of the Svalbard clean-up operation (see Figure 1) lies on carbon dioxide emissions on the one side and impacts on biological diversity on the other. For all transport processes the CO₂ emissions to air are added up (see Table 1), as the significant impact there clearly is the combustion of fossil fuels. So the LCA approach applied here accounts for fuel use only and does neglect any infrastructure processes; that is the use of airports, roads or for instance the ships and airplanes themselves. The functional unit for which the emissions are calculated is the unit of 1 arctic clean-up operation. In this case it comprises the about 120 passengers that the deployed polar vessel can house including their transport to and from the remote location of the clean-up itself. During their one-week trip, circa half a metric ton has been collected (for explanation see below). Still, the functional unit here is the one arctic clean-up operation and not the amount of plastic collected because the emissions are specific for the chosen remote setup while 500 kg of marine plastic debris could also have been removed somewhere else with probably less effort but different side-specific effects. Furthermore, the positive environmental impacts of the removal of plastic debris from beaches, as the overall goal of the operation, will be described in the next subchapter.

Table 1: Total emission balance for the functional unit of one clean-up operation

Process	Carbon emissions in t	Remarks
a) Passenger transport to Oslo	20.42	101g/km/pax
a) Passenger transport from Oslo	20.42	101g/km/pax
b) Passenger transport to Svalbard	17.61	76g/km/pax
b) Passenger transport from Svalbard	17.61	76g/km/pax
c) Arctic boat trip	191.56	from 70000 l MGO
d) Zodiac transport to & from beaches	0.695	from 300 l bensin
e) Cleaning of beaches	overall goal output	positive ecolog. Impact
f) Transport of collected plastic	0.0065	13m³ shipped 1050km
g) Landfilling of plastic	neglectable	landuse for landfilling
	268.30	sum of emissions

a)      The first process in this operation is the transportation of the passengers (pax) from their places of residence to Oslo. Oceanwide Expeditions provided the nationalities of the participants from which the average flight distance of 1789 km was calculated with the respective capital city as the starting point of the journey (see Table 2). The carbon emissions of 101 g per passenger kilometre given by British airways (2015, p. 6) comply well with other values from the International Civil Aviation Organization (ICAO, 93 g/km/pax, see Figure 2) or the webside carbonindependent.org (101 g/km/pax).

Table 2: Passenger distances travelled by flight, data from Oceanwide Expeditions

Number	Nationality	mean dist. capital - Oslo (km)	(weighted)
1	Austria	1353	1353
14	Germany	839	11746
1	Spain	2391	2391
1	France	1343	1343
11	Great Britain	1155	12705
20	Israel	3568	71360
3	Italy	2009	6027
44	Netherlands	914	40216
6	Norway	0	0
4	Sweden	417	1668
7	USA	6239	43673
1	South Africa	9717	9717
113			202199
	mean distance per person in km		1789
	plus distance Oslo-Svalbard in km		2050

Figure 2: ICAO carbon emissions calculator, output for Oslo – Longyearbyen equals 93 g CO2 / km / pax

b)      Next, the same is calculated for the distance of 2050 km between Oslo and Longyearbyen flown with Norwegian airlines. They give 76 g/km/pax as their averaged carbon emissions. Both processes a) and b) occur again as the passengers return to their places of residence after the excursion.

c)      Then, the transport process of the arctic boat trip itself followed which used up 70 m³ of marine gas oil (MGO), a light shipping fuel with low sulphur content (Bengtsson et al, 2011, p. 98). MGO emits 74 g CO₂ per MJ and has a heating value of 43 MJ per kg (Bengtsson et al, 2011, p. 102). Together with its density of 890 kg/m³ (Caltex, 2011), the resulting total carbon emissions of the polar expedition vessel are 192 tons. 

d)      Additionally, trips from the vessel to the shores were made with several zodiacs that used 300 litre of gasoline during the expedition altogether. With emissions of 16.6 kg CO₂ per 100 km (EPA, 2006), a total amount of 695 kg was emitted from this process. 

e)    The cleaning of beaches is done by picking up waste by hand by the passengers. They collected all waste fractions, even though the biggest part was plastics. Different attempts to quantify the positive impact of the removal of litter itself will be described in the next chapter.

f)      After the expedition itself, the plastic waste collected from the beaches around the archipelago was shipped to the mainland (Tromsø) for landfilling. The reason why it cannot be incinerated for energy recovery is that the material partly consists of fishing gear. The nets and ropes would get tangled in the automatic equipment used in recycling and incineration plants (Lokalstyre Longyearbyen, 2016). It was assumed that a freighter smaller than 2000 dwt was used for the transportation which emits 9 kg of CO₂ per t of freight on the distance of 1050 km  (CMP SPINE LCI dataset). The other greenhouse gas emissions were converted to CO₂ equivalence with a calculator provided by the United States Environmental Protection Agency (EPA, 2014), which delivered a total of 13 kg CO₂ equivalence. The resulting emissions for 500 kg material transported (see Table 2) are then 6.5 kg.

Table 3: Calculation of the weight of the collected plastic waste

Mean weight of 1 m³ of material in kg, packed with low density
Plastic bags	39
Hard plastic	72
Polystyrene	14
Mean value	41.67
Calculated for 13 m³	541.67
rounded due to less packed containers	500
Data from EPA, http://www.epa.vic.gov.au/business-and-industry/lower-your-impact/~/media/Files/bus/ EREP/docs/wastematerials-densities-data.pdf

g)      The landfilling itself also has an environmental impact which is very little though. As plastics are relatively inert when landfilled, there occur no emissions to air or water from the disposal. Similarly, the use of land, that is the respective part of space occupied by the landfilling site, by the 13 m³ considered here is very little and can thus be neglected. 

Evaluation methods for positive environmental impacts

•         Impact on local wildlife, observed changes 
•         Differences in the amount of plastics found in the stomachs of Fulmars as indicator species  on Svalbard and comparable habitats elsewhere that are not cleaned 
•         Effects of awareness raising actions on (littering) behaviour 
•         Amount / percentage / kilometres of beach or coastline cleaned (in contrast to the space occupied by the landfilling then)