Assessing marine resource damage and the clean-up cost of oil spills Francois Bonnieux, Pierre Rainelli

To cite this version:

Francois Bonnieux, Pierre Rainelli. Assessing marine resource damage and the clean-up cost of oil spills. 4. Annual Conference of the European Association of Environmental and Resource Economists, Jun 1993, Fontainebleau, . 16 p. ￿hal-01937072￿

HAL Id: hal-01937072 https://hal.archives-ouvertes.fr/hal-01937072 Submitted on 7 Jun 2020

HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés.

Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives| 4.0 International License PR/11.12.92

THE EUROPEAN ASSOCIATION OF ENVIRONMENTAL

AND RESOURCE ECONOMISTS

Fourth Annual Conference

June 30 .. July 3, 1993

Fontainebleau - France

ASSESSING MARINE RESOURCE DAMAGE AND THE CLEAN-UP COST OF OIL SPILLS

Bonnieux F. and Rainelli P.

Institut National de la Recherche Agronomique Station d'Economie et Sociologie Rurales 65, rue de St-Brieuc - 35042 Rennes cedex

June 1993

DOCUMENTATION ÉCONOMIERURAL ER ENNES r~l/-éSl 1111111 111111111111111 IIIII IIIII IIII IIII tm-F, * 0 1 7 4 6 5 * -11 :~:/S 2

ABSTRACT

ASSESSING MARINE RESOURCE DAMAGE AND THE CLEAN-UP COST OF OIL SPILLS

Bonnieux F., Rainelli P.

This paper presents a discussion of some of the social costs which resulted from the Cadiz's which damaged 350 kilometers of French coastline in 1978. This case is particularly interesting for several reasons.

(i) The is the largest vesse! spill in history, over five times the amount spilled by the Exxon Valdez in 1989, and this is a reference point.

(ii) It reveals the difficulties for economists in evaluating natural damage costs since these costs are highly dependent on the assumptions made in order to calculate them, the models used and the scarcity of data available.

(iii) As the lawsuits were settled only very recently (1992), this case allows for the first longitudinal study of the issues involved in the economic valuation of a massive oil spill.

This paper is divided into two sections. The first one is devoted to the non-market components of marine resource damage. Recreation and amenity losses are considered first. The various estimates which were produced are discussed. Then, ecological damage due to a perturbation of an ecosystem is defined. A monetarization of biomass Joss based on a trophic chain mode! is given. The second section gives an overview of the main problems which were posed during the clean-up operations. The limitations of a static analysis of such clean-up are illustrated and a dynamic approach is proposed. 3

The wreck of the Braer in the Shetland Islands in January 1993, coming so soon after December 1992 oil spill off Northwest has focused attention on traffic risk and natural resource damage. Four years ago, the Exxon Valdez oil spill in Alaska's Prince William Sound was a high-profile case that resulted in one of the largest environmental settlements in the US history (about$ 1 billion). This wreck led to the passage of the US Oil Pollution Act of 1990 which extends the scope of recoverable damages for oil spills. In fact the worst oil spill to reach land occurred in (France) in March 1978 when the Amoco Cadiz ran aground along the coast of Brittany. The amount of oill spilled into the ocean from the Amoco Cadiz was over five times the amount spilled from the Exxon Valdez (220 000 metric tons of crude oil).

After every oil spill the same questions arise : what can be done to limit the risk of oil spills ? How can we contain and limit the extent of disasters when they happen ? How can we evaluate the damage ? Each oil spill has its specific features but there are always lessons to be leamt in various fields. Marine ressource damage valuation and the management of clean-up operations pose very difficult problems (Bonnieux, Rainelli et al., 1980; Bonnieux and Rainelli, 1991) which are reviewed in this paper. Comments are based upon our own experience with the Amoco Cadiz case. As the lawsuits were settled only very recently (1992), this case allows for the first longitudical study of the issues involved in the economic valuation of a massive oil spi Il.

1. MARINE RESOURCE DAMAGE

The damage to marine resource resulting from a discharge of oil on the shoreline stems from the reduction in the service flow from the environment as a consequence of contamination by hydrocarbons. Services are defined in reference to the functions that marine resources support. Iwo main categories of services are provided by marine resources. The first category is related to use values and non-use values. It refers to the economic concept of damage : how much money it would take to make everyone as well off as they were before the oil spill occurred (Freeman and Kopp, 1989). The second category relates to services which are provided by the normal functioning of the marine ecosystem. The stress suffered by the lower trophic level organisms creates an ecological imbalance. This imbalance induces biological and economical consequences. There are obvious links between these two categories e.g. commercial and sport fishing are supported by the biological productivity of the ecosystem. This section is restricted to two non-market components of the total damage : (i) recreation and amenity losses (ii) assessment of the perturbation of the ecosystem. 4

11. Recreation and amenity losses

There are important links between outdoor recreation and the environment. While ail outdoor recreation does not depend on the natural environment, much of it does. In Brittany, a good deal of outdoor recreation relies upon marine resources and marine assets that cannot be easily reproduced. The attractiveness of resorts and the quality of the shoreline constitute important determinants of any demand for recreation.

Pollution from the wreck of the Amoco Cadiz adversely affected the physical characteristics of a lot of recreation sites in Brittany, it therefore induced a decline in benefits for both users and non users. Welfare losses from any environmental deterioration for an individual can be measured in monetary tenns. The conceptual basis for determining this monetary value rests on the plausible assumption that when confronted with two alternative situations an individual can indicate which s/he prefers, or state s/he has no preference.

In order to show the way in which losses from an environmental disaster can be measured let us consider a single recreation site such as a beach. There is a demand function which relates the quantity of beach services demanded, measured in beach-days per season, to the price of these services and other variables. This demand function can also be interpreted as a marginal willingness to pay function, relating the marginal value of a beach-day to the quantity ofbeach-days and other variables.

In figure 1, D 1 is the demand curve in beach-days before pollution. Suppose the price of admission to this beach is OA per day (OA can be zero), then the recreational use will be ON l · The value of this beach to users, given its initial quality, is the consumers surplus as measured by area ABC.

Figure 1. Beach demand and losses due to water quality deterioration

8

D1

D F D2

0 N2 N1 beach-days/season 5

Assume that beach quality has deteriorated, users would be willing to pay less at the margin to use this polluted beach. In economic terms the effect is to shift the demand curve to the left. The new demand curve is shown by D2 and the consumers surplus is now measured by the area ADE. Therefore the decrease in consumers surplus gives the net loss due to beach pollution; it is measured by the area BCED.

The net loss can be divided into two components. The first is the decrease in value to those users who came the beach even at the low levels of quality resulting from the pollution. This is the area BDEF. This area represents the decreased willingness to pay to visit this beach rather than do without, eg tourists who came to Brittany in 1978. The second results from the lesser attractiveness of this beach relative to alternative beaches and alternative expenditures, eg tourists who did not corne to Brittany in 1978. It cornes from the decrease in the number of beach-days which declines to ON2_ The net loss associated with this decline is the area CEF.

A significant amount of work dealing with non market valuation is now available. It is usual to consider benefit transfers (i .e. the application of monetary values obtained from a particular non market goods analysis to an alternative or secondary policy decision setting) as a relevant approach in damage assessment (Brookshire and Neill, 1992 ; Ward and Duffield, 1992). But at the time of the Amoco Cadiz oil spill, the valuation of non market damages received comparatively little economic attention, especially in France. At that time, the investigators involved in this case had to develop original studies. Although economists would always prefer to have more resources and more time, the reality of the litigation setting is that in this case this was not possible. So we had to do our best in a limited period of time and with a limited amount of money. A variety of estimates were produced. They can be classified according to three categories : (i) estimates based upon observed behaviour (implementation of the travel cost approach) ; (ii) estimates based upon preference elicitation mechanisms (use of contingent behavior, insurance, compensation and willingness to pay) ; (iii) estimates based upon expert opinion (use of unit value per beach day lost). Table 1 summarizes the main results of these studies which dealt with recreation and amenity lasses.

Table 1. Recreation and amenity lasses

Valuation in nùllion Category Method 1978 French francs Travel cost 6 Tourist who did corne Contingent behavior 38.2 in 1978 Insurance 10.3 - 23.5 Compensation 8.8 - 32.3 Tourists who did not corne Willingness-to-pay 84.1 in 1978 Travel cost 129.9 Residents Unit value 125.6 Insurance 88 - 116 6

We must emphasize that the estimates were quite consistent, except for the output of the travel cost model for tourists who did corne in 1978. These results, despite some restrictive assumptions and some weakness of data, show that non market damage is very high and is comparable with market damage (Bonnieux and Rainelli, 1991).

12. Assessment of the perturbation of the ecosystem

The central issue which arises when assessing ecological losses following a perturbation of an ecosystem is : what should be counted as damage, and how should this damage be measured ? In order to understand what ecological losses mean from an economic point of view, the ecological impact has to be determined and quantified. Only then, can we attempt to monetarize the ecosystem perturbation.

An important point in any quantification of damage to the ecosystem is the resource recoverability as measured in reference to baseline level services, i.e. the conditions existing before the oil discharge. It corresponds to the amount of time needed for an injured resource to recover and reach its initial level. The ecosystem recovers at natural recovery rate which depends on the magnitude and the toxicity of the oil discharge. This rate can be accelerated by human operations. (Ward and Duffield, 1992, p. 153).

Figure 2 illustrates a simple time profile which describes the Joss of natural resource services after the oil spill. The baseline service level is reached after a timespan which depends on the natural recovery rate or human action (restoration recovery).

Figure 2. Loss of natural resource services after an oil spill and their recovery rate

Natural Resource Services

Restoration Recovery

Oil spill tirne 7

In the case of Amoco Cadiz oil spill, marine scientists have evaluated perturbations affecting the nonnal functioning of the ecosystem by the way of biological indicators based on macrofauna analysis over a period of about 10 years. Sandy beaches were sampled because fine sands are well represented along the coast and these beaches have average hydrodynamic conditions in the ecosystem (Glemarec, 1986). Among the sites which were monitored, the most interesting ones are downstream sands in a small estuary located Jess than 10 kilometers from the place where the supertanker ran aground (Aber Wrac'h). In this area both macrofauna and oil contamination of the sediments were studied. Figure 3 shows that one year after the wreck the oil contamination was still more than 1000 ppm (1 g of oil per kg of sediment). Even though the decontamination process was very rapid in the beginning, four years were needed to meet an acceptable level of oil in the sediments.

Fig. 3. Level of oil in sediments over the time in the dowstream sands of the Aber Wrac'h (in ppm)

hydrocarbons

10000

1000

10 20 30 40 50 60 70 80 months ppm (log)

Source : Marchand and Bodennec, 1985.

The ecological impact is characterized by two elements : (i) mortality, (ii) recovery in population species. Mortality is a direct result of oil toxicity. This toxicity was increased by the severe stonn which caused the grounding of the vesse!. The oil was dissolved in the entire column of water, so the oil content in deep water was almost as high as in water nearer the surface. Substitute population species appeared in the gap left. Three distinct phases can be distinguished in a post spill marine ecosystem (Le Moal and al., 1991).

- In the initial phase, the degradation phase, the light fractions of crude oil and the aromatic hydrocarbons cause the destruction of the ecosystem. Opportunistic species develop after six months.

- The recolonization phase occurs in two successive stages. The first one is a primary 8

recolonization which is partial and incomplete because only a few spec1es of the original species are present. Four years after the accident, the second recolonization stage begins.

- Thirdly the restructuration phase, which is observed six years after the accident, is a regulation process. The community shows readjustments, the competition between species becomes controlled by predators, and a new equilibrium is achieved.

The biological process which explains the recovery can be described usmg three synthetic parameters : the number of species S characterizing how rich the ecosystem is; A, the abundance ( or density) and the biomass B. These three parameters drastically decrease reaching a minimum 8 months after the accident as shown by figure 4. From 8 to 28 months these three parameters and especially the abundance increase. At 36 months there is a drop corresponding to the ecotonal stage. The stabilization is achieved after a period of six years (Glemarec, 1991).

Figure 4. The marine ecosystem after the oil spill : evolution of syntheticparameters (in the Aber Wrac'h)

br2.pre A s B

A

time

0 12 24 36 48 60 72 84 months 1978 79 80 81 82 83 84 years

Source : Glemarec, 1991.

Three conclusions can be drawn from the above. Firstly, a comparison between figure 3 and figure 4 shows that the decontamination required about 70 months while the ecosystem took 84 months to reach its new equilibrium. Secondly, if the decontamination follows a linear or quasi-linear time function, the evolution of the synthetic parameters is not a simple function of time. Thirdly, biomass is the simplest parameter to use to quantify the ecological impact because its evolution is the most simple over time. It is a proxy variable which can be used to estimate the perturbation of the ecosystem in a reasonable delay ( about one year after the oil spill). 9

Biomass can be considered as the main component of the marine food chain, the process whereby living organisms obtain food energy by consuming other organisms. The food energy is transferred in the form of living matter at each step up to commercial marine products. Any loss of biomass represents a potential decrease of commercial species which would have been produced. If we know the rate at which food energy flows through the ecosystem and the path it follows, it is possible to value the impact of a perturbation to the ecosystem, (Isard, 1972, p.55).

A simple four-staged mode! quantifying the biological relationships of the marine food system is considered. The zero trophic level relates to the phytoplankton and sea weeds which are the main producer plants in coastal waters. Phytoplankton production depends mainly on the rate of photosynthesis and the rate of respiration. This is the level of the producers. The first trophic level includes the primary consumers, the herbivores, mainly zooplankton and also fish such as the grey mullet. The second trophic level corresponds to the primary carnivores. The third trophic level corresponds to the secondary carnivores (species eating camivorous invertebrates or fish).

Let Y; the potential production at level i (i = 0, 1,2,3). The amount of phytoplankton required to produce one unit of herbivore is a 01 . In the same way the functional relationship from a trophic level to the upper one is a11 , a 1J . However for the first and second trophic levels there are commercial and non commercial species, so other transformation coefficients

/J, and /31 are introduced. Then non commercial output at the first level is /J, Yi and the commercial output is ( 1-PiJYi . The non commercial output at the second level is /32 Yi and the commercial output is (1 - /32 ) Yi- It is supposed that total phytoplankton production is non commercial, while total secondary carnivore production is commercial (Chart 1) . 10

Chart 1. Simplified mode! of marine food chain

Trophic level 0 ______....__.....______---1 producers L------~---....::.,______-J

Trophic level 1 Zooplankton I Herbivorous fish herbivores -----~------t------1Non commercial output I Commercial output f31Y, ( l-f31JY,

Trophic level 2 Carnivores 1 Fishes 1 and crustaceans primary carnivores Non commercial output Commercial output /32½ ()-f32JI'i

Trophic level 31 Fishes 2 secondary carnivores ======P=o=t=en=t=ia=l=pr=o=du=c=u=· o=n=Y= 3 ======

The mode! can be written with five equations :

Y, = f31Y, +(1-/J)Y, ½ = /32½ +(J -f32JI'i Y, = ao1Yo ½ = a12/J1Y, ½ =a23/J2I'i and potential commercial output equals : ( 1-/31) Y, +( 1-/32) +Y;, this amount is used to value food chain flows.

Concerning the transformation coefficients a, we admit the ratio of 10 : 1 as suggested by Petersen's studies, (Isard 1972 p. 246). In order to estimate /31 and /32 it was supposed that the structure of landings in the polluted area before the oil spill, reflected the structure of potential commercial output. Let r = /32I'i I ( 1- f32)I'i the ratio between fish belonging to the third trophic level and fish belonging to the second level, and <5 =()-/31)Y, / (J-/32)Y2 the ratio between herbivorous fish and fish belonging to the second trophic level. y and <5 being given by published data then, /31= 0.994 and /32 = 0.534. Chart 2 summarizes the results on the basis of a potential production at Y0 of 1000 metric tons. 1 1

Chart 2. An application of the marine food chain to the polluted area (potential output in metric tons)

Level 0 : phytoplankton ; algaes 1000

Level 1 : herbivores= 100 Zooplankton Herbivorous fish 99.94 0,06

Level 2 : primarv carnivores = 9. 9940 Carnivores 1 Fishes 1 and crustaceans 5.3378 4.6562

Level 3 : secondary carnivores= 0.5338 fishes 2

According to marine biologists, (Glemarec, 1991), the Joss of non commercial marine biomass reached 260 000 metric tons of wet dead weight during the first six months. Over the six years necessary to obtain a new equilibrium the total biomass Joss was 600 000 tons corresponding to 31 500 tons of commercial species. Using the catch average price the potential damage was 195 millions 1978 Francs.

2. CLEAN-UP AND EMERGENCY RESPONSE : MARGINAL AND COST-EFFECTIVENESS ANALYSES

When the supertanker Amoco-Cadiz grounded on March 16th 1978 she was loaded (220000 metric tons of Arabian and Iranian crude oil). As the result of winds blowing in the onshore direction and the proximity of the wrecking to the shore about 35 percent of the oil was driven onto the coast. The oil and water formed an emulsion, termed "mousse", containing 20 to 30 percent oil. About 250 thousand tons of mousse were deposited along 350 km of coastline injuring na tu rai resources and affecting the economic activity of the area.

Because clean-up activities represent the largest component of social costs of any large oil spill, these activities raise a major question for decision-makers : how many goods and services have to be used to restore the shoreline ? Basically there are three different positions to operate the cleanup :

- the laisser-faire. Wave and tidal action is supposed to allow a good self-cleaning along rocky and high energy beaches. Man's intervention using dispersants is considered to be harmful to marine life. This is the position of the tanker owners, who prefer the natural recovery without any clean-up effort (White and Nichols, 1982). 12

- the full restoration. Conservationists, fishermen, oystermen, hotel and restaurant owners and residents who direct losses, are in faveur of using maximum effort, against the spill in order to minimize the reduction in losses which result from the oil discharge. These people are in faveur of a rapid and total cleanness of the coast.

- the rational clean-up effort. laisser faire and complete cleanness are corner solutions. Since there is a trade-off between increasing clean-up costs and reducing losses in use and in non-use of the shoreline and coastal resources, the problem is to determine the efficient level of the clean-up effort.

2.1. A static analysis of cleanup

The value of the shoreline and of the marine resources for producers (fishermen, men, cafe-hotel-restaurant owners) and consumers (residents and tourists) can be captured with a simple social welfare function. Total welfare depends on the quality of the environment : cleanness can be used as a proxy variable for this complex parameter. Total welfare W is supposed to be a decreasing function of the amount of oil spilled (Figure 2). This relationship can be viewed another way ; welfare increases with the quantity of oil removed and the marginal cost of damage increases with the amount of oil spilled (up to a level above which non-convexity can occur).

Fig. 5. Social welfare as a fonction of cleanness

w

) W =W(C. - C0 =W(x) x = c· - Co and ôW I àc < 0 c•: total oil spilled

: C0 baseline condition c· - Co : OÎl removed A: cos t of damage

Co C* oil s pilled

oil removed 13

Concerning the clean-up efforts, ail available data demonstrate the declining productivity per unit of input over time. Initially, one man could clean about 500 square meters of surface area per day. But by the end of the clean-up operation, this surface area fell to 20 to 50 square meters per day (Bellier, 1979). The most severely affected and most accessible parts of the coast were cleaned first, followed by regions of lower priority where hydrocarbon deposition was either not so great or where access for heavy equipment was more difficult. During the first ten days of pumping, liquid mousse pumped per man fell very quickly from 1.2 cubic meters on the first day to between 0.07 and O. 16 cubic meters on the fifth day (Meade, 1982).

Figure 6. Optimal level of cleanup becomes very high when the shoreline is nearly clean ( close to zero on the horizontal axis). The CmD curve shows the marginal benefits from the clean-up activity in terms of services provided by marine natural resources. The optimal level of cleaning will be reached when the marginal clean-up cost is exactly equal to the marginal social benefit, point B. At this point the quantity

0 A pollution AC of oil has been removed. The total - ························································································· clean-up cost associated is equal to the restoration triangle ABC. At this point the amount AO This decline in productivity per of oil remams. This amount AO man-day is illustrated in Figure 6 by the corresponds to residual damage which CmN curve which shows that the cleanup equals the compensatable triangle ABO. In effort per metric ton of oil spilled is Iow for theory compensatable damage includes the a large amount of hydrocarbon (right side clean-up costs (triangle ABC) plus the of the horizontal axis). Conversely the cost residual damage (triangle ABO). of removing one more metric ton of oil

2.2. A dynamic analysis of clean-up

A static analysis is of little use to the decision maker since specific information at a given moment is needed to allow decisions to be made. Every decision involves forecasting how the benefits from the measures taken will evolve over time. For example it was decided to 14

place booms directly across estuaries to protect them from the oil. But weather conditions greatly reduced their effectiveness because of the magnitude of the waves. In the same way, the scraping of sand from a lot of beaches can be criticized ex post since these beaches were not endangered of being polluted. Basically, in a major emergency it is not possible to state with certainty what consequences a particular measure of protection will have. Will a given set of measures actually achieve its goal ? And on the demand side, is it certain that the services from an injured resource will actually be desired in the future ? The main implication of uncertainly on both sides, supply side and demand side, is the existence of what is called an "option price".

Decision-makers cannot know in advance wether the decision taken will be a success or a failure. However the risk is that the action taken may be too much rather than too little since officiais have an important risk aversion and fear public discontent. For the Amoco-Cadiz this problem was increased by the existence of sensitive areas such as bird reserves with auks, puffins, murres and razorbills for which the injury could have irreversible effects.

Three issues must be taken into account : (i) decisions are taken under uncertainly, (ii) the decision process is sequential : it is possible to obtain further information about the consequences of a choice, (iii) the possibility that a choice will have irreversible consequences (no choice is a choice).

In these circumstances when the decision-maker can make the decision after any uncertainty is resolved, quasi-option value has to be considered (Henry, 1974). The concept of quasi-option value refers to the increase in expected net benefits of not undertaking a project which could have irreversible consequences. In emergency response to an oil spill it is the reverse, since the laisser-faire or the minimum clean-up costs would lead to irreversible effects. Decisions involving irreversible consequences are therefore more conservationist once we open up the possibility of learning more by choosing protective solutions. In ttùs case the emergency response is always more costly than it would have been with perfect information,. but the conservationist choice induces a better saving of natural resources. 15

As shown in figure 7 the preventive Figure 7. The shift of the optimum level of decision to protect sensitive areas leads to effort in a dynarnic analysis the marginal cost of cleanup CmN 1 instead of CmNo. The consequence is a shift of the CmNO optimum level of restoration effort from Ao CmD to A1 (towards more cleanness). The difference between the two marginal curves can be interpreted as a quasi-option value.

1-.:::::=------=:::::::~-----·-­ Al AO pollution

restoration

For the Arnoco Cadiz oil spill, total French cleanup costs were between 103 and 114 million 1978 US dollars including emergency response, (Anderson et al., 1983, p. 54 in NOAA, 1983). The estimate for the land based component of the governmental clean-up operation was four times that of the at-sea component. If we include the expenses incurred by local communities, the total cost was 134 million 1978 US dollars i.e. 609 dollars per metric ton of oil spilled. Compared with the Torrey Canyon oil spill this is a large amount (nearly twice as much). More important costs per metric ton have been observed in the past but they were not significant for they concerned small oil spills (4 to 5 thousand metric tons). In the Exxon Valdez case where 40 000 metric tons were spread, clean-up costs reached about 50 000 1989 US dollars per metric ton, a considerable amount even if we compare 1978 dollars and 1989 dollars ! Such a difference may be explained by geographical factors and the type of oil, but also by the willingness of Exxon to pay because of its continued involvement in Arctic exploration of new oil fields. 16

REFERENCES

Anderson R.C. ; Congar R., Meade N.F. ; 1983. Emergency response, clean-up, and restoration in N.O.A.A. (ed). Assessing the social costs of oil spill : the Amoco Cadiz case study. US Department of Commerce, Washington D.C .. Bellier P ., 1979. Lutte contre les pollutions marines accidentelles par les hydrocarbures: l'expérience de l'Amoco-Cadiz - CEDRE Report, Brest. Bonnieux F., Rainelli P., et al., 1980. Impact socio-économique de la marée noire provenant de l'Amoco-Cadiz. INRA-UVLOE Report, Rennes. Bonnieux F., Rainelli P., 1991. catastrophe écologique et dommages économiques : problèmes d'évaluation à partir de l'Amoco-Cadiz. INRA, Economica, Paris. Brookshire D.S., Neill H.R., 1992. Benefit transfers: conceptual and empirical issues. Water Resources Research, 28 : 651-653. Freeman A.M. ; Kopp R.J. ; 1989. Assessing damages from the Valdez oil spill. Resources for the Future, n°96. Glemarec M. ; 1986. Ecological impact of an oil spill : utilization of biological indicators. Water Sc. Tech. 18 : 203-211. Glemarec M. ; 1991. Ecological impact of an oil spill utilization of biological indicator. Report to Infopol 91, Brest session. Henry C. ; 1974. Option values in the economics of irreplaceable assets. Review of Economie Studies Symphosium on Economies ofExhaustible Resources: 89-104. Isard W. ; 1972. Ecologic-economic analysis for regional development. The Free Press, New­ York. Le Moal Y. ; Majeed S. ; Thouzeau G. ; 1991. Perturbation and recovery after two major oil spills (Amoco Cadiz and Tanio) in Terrestrial and aquatic ecosystems, Raxera O., (ed) Ellis Horwood : 417-421 . Marchand M. ; Bodennec C. ; 1985. effets de la pollution de l'Amoco Cadiz sur l'ostréiculture. UBO-IFREMER, Report, Brest. Meade N. ; 1982. La marée noire de l'Amoco-Cadiz : analyse des coûts des opérations d'intervention d'urgence, de nettoiement et de remise en état de l'environnement, m OCDE: 145-166. O.C.D.E. 1982. Le coût des marées noires. OCDE, Paris. White I.C. ; Nichols J.A. ; 1982. Considérations pratiques concernant le coût des marées noires in OCDE, 77-88. Ward K. M .; Duffield J.W.; (ed) 1992. Natural resources damages : law and economics. Wiley, New-York. PR/li 11.92

THE EUROPEAN ASSOCIATION OF ENVIROt-,~IEi'.1TAL

AND RESOURCE ECONOI\IIISTS

Fourth Annual Conference

June 30 - July 3, 1993

Fontainebleau - France

ASSESSING MARINE RESOURCE DAMAGE AND THE CLEAN-UP COST OF OIL SPILLS

Bonnieux F. and RaineUi P.

Insrirur N:Hion:il de la Recherche Agronomique

Station d'Economie et Sociologie Rurales 65. rue de Sr-Bncuc - 350-e Rennes cedex

June 1993