1

By its application, the European Commission requests the Court to declare that, by failing to adopt the measures necessary to comply fully and properly with all the requirements imposed on it by Article 5(4) of Council Directive 91/676/EEC of 12 December 1991 concerning the protection of waters against pollution caused by nitrates from agricultural sources (OJ 1991 L 375, p. 1), read in conjunction with Annex II.A, points 1 to 3 and 5, Annex III.1, points 1 to 3, and Annex III.2 to that directive, the French Republic has failed to fulfil its obligations under that directive.

2

According to the eleventh recital in the preamble to Directive 91/676, action programmes ‘should include measures to limit the land application of all nitrogen-containing fertilisers and, in particular, to set specific limits for the application of livestock manure.’

3

The purpose of that directive, as set out in Article 1 thereof, is to reduce water pollution caused or induced by nitrates from agricultural sources and to prevent further such pollution.

4

Article 4(1) of that directive provides:

‘With the aim of providing for all waters a general level of protection against pollution, Member States shall, within a two-year period following the notification of this Directive:

...’

5

Article 5 of Directive 91/676 provides:

‘1.   Within a two-year period following the initial designation referred to in Article 3(2) or within one year of each additional designation referred to in Article 3(4), Member States shall, for the purpose of realising the objectives specified in Article 1, establish action programmes in respect of designated vulnerable zones.

...

3.   Action programmes shall take into account:

4.   Action programmes shall be implemented within four years of their establishment and shall consist of the following mandatory measures:

...’

6

Annex II.A, points 1 to 3 and 5, to that directive, that annex being headed ‘Code(s) of good agricultural practice’ is worded as follows:

‘A code or codes of good agricultural practice with the objective of reducing pollution by nitrates and taking account of conditions in the different regions of the Community should contain provisions covering the following items, in so far as they are relevant:

...

...’

7

Annex III.1, III.2 and III.3 to that directive, that annex being headed ‘Measures to be included in action programmes as referred to in Article 5(4)(a)’, states:

8

Article 5 of Directive 91/676 was transposed into French law by Decree No 2001-34 of 10 January 2001 on action programmes to be implemented for the protection of waters against pollution caused by nitrates from agricultural sources. The provisions of that decree were codified in Articles R. 211-80 to R. 211-85 of the Environmental Code.

9

The order of 6 March 2001 on action programmes to be implemented in vulnerable zones in order to reduce pollution caused by nitrates from agricultural sources (JORF of 25 March 2001, p. 4712; ‘the order of 6 March 2001’) was adopted pursuant to Decree No 2001-34.

10

The order of 1 August 2005 establishing minimal requirements to be introduced in vulnerable zones and amending the order of 6 March 2001 on action programmes to be implemented in vulnerable zones in order to reduce pollution caused by nitrates from agricultural sources (JORF of 16 September 2005, p. 15019; ‘the order of 1 August 2005’) establishes such requirements in respect of, inter alia, methods for calculating the maximum quantity of nitrogen contained in livestock manures which can be spread per annum.

11

The circular of 15 May 2003, headed ‘Instructions on the implementation of the programme to control agricultural pollutions [Programme de maîtrise des pollutions d’origines agricole: PMPOA]: Simplifications and Adjustments’ determines nitrogen discharge values by types of animals (‘the circular of 15 May 2003’).

12

Decree 2011-1257 of 10 October 2011 on action programmes to be implemented for the protection of waters against pollution caused by nitrates from agricultural sources (JORF of 11 October 2011, p. 17097), amended Articles R. 211-80 to R. 211-85 of the Environmental Code.

13

The order of 19 December 2011 on national action programmes to be implemented in vulnerable zones in order to reduce pollution of waters caused by nitrates from agricultural sources (JORF of 21 December 2011, p. 21556; ‘the order of 19 December 2011’) was adopted pursuant to Decree No 2011-1257.

14

The order of 6 March 2001 contains an annex headed ‘Technical framework for the development of action programmes’. Section 2 of that annex contains, inter alia, points 2.3 to 2.5. Point 2.3., headed ‘Balance of nitrogen fertilisation on each plot of land, including for irrigated crops’, provides:

‘The quantity of fertilisers applied shall be limited on the basis of the balance between the foreseeable nitrogen needs of crops and the additions and sources of nitrogen of any kind. The additions of nitrogen to be taken into account concern all fertilisers ...

The rules governing land application to be respected in order to ensure that balanced fertilisation, including adjustments associated with irrigated crops shall be set out in the action programme. Those rules shall minimally cover, by crop, distinguishing irrigated and non-irrigated crops, the factors for calculation of the quantity (predictible yields, ground nitrogen provision ...) and rules governing fractionation.

Those factors of and rules for calculation shall be determined on the basis of available local agronomic data taking into consideration the level of nitrate leakage compatible with water quality requirements.

The quantities of nitrogen added by livestock manures or other organic fertilisers ... must be known by the farmer. Where that material is obtained from outside the farm, the data enabling farmers to have that information, and how that material is to be classified as a type of fertiliser, must be required from the suppliers of that material.’

15

Point 2.4. of the order of 6 March 2001, headed ‘Types of fertilisers and periods of prohibition on land application’, fixes the minimum periods during which the land application of various types of fertilisers is prohibited. According to the table within that Point, for arable crops planted in the autumn, the land application of type II fertilisers is prohibited from 1 November to 15 January and that of type III fertilisers from 1 September to 15 January. For arable crops planted in the spring, the land application of type I fertilisers is prohibited from 1 July to 31 August, that of type II fertilisers from 1 July to 15 January, and that of type III fertilisers from 1 July to 15 February. For grasslands planted for more than six months, the land application of type II fertilisers is prohibited from 15 November to 15 January and that of type III fertilisers from 1 October to 31 January.

16

Point 2.5. of the order of 6 March 2001, headed ‘Specific conditions for land application’, provides:

‘...

2° On steeply sloping ground

On steeply sloping ground the land application of fertilisers is prohibited. The action programme shall specify the situations where the prohibition applies, taking into consideration risks of run-off from the land where the fertiliser is applied or, otherwise, the percentage of slope above which land application is prohibited.

3° On ground which is frozen, flooded or waterlogged, or snow-covered:

The table below shall determine the restrictions on land application. In the case of regulated land application, the action programme shall specify the conditions in which land application is to be carried out. [According to the table referred to in that Point, for frozen ground, the land application of type I and III fertilisers is prohibited or regulated and that of type II fertilisers is prohibited. As regards snow-covered ground, the land application of type I fertilisers is prohibited or regulated and that of type I and II fertilisers is prohibited.]

On ground only superficially frozen, with alternating freezing and thaw over 24 hours, land application is permissible in respect of all types of fertilisers.

...’

17

Annex II, point 1 of the order of 1 August 2005, headed ‘Calculation of the quantity of nitrogen contained in livestock manure available on the farm’, provides:

‘This concerns the production of nitrogen by animals, obtained by multiplying the number of animals by the nitrogen production values per animal for land application, corrected, where appropriate, by the quantities of nitrogen spread on third-party farms and the quantities of nitrogen obtained from third-parties.

...’

18

Article 2 of the order of 19 December 2011 provides:

19

Annex I, Section II of that order, headed ‘Requirements relating to storage of livestock manure’, provides:

20

Annex II, A to E, to that order, determines the nitrogen excretion standard rates by animal species for the implementation of Section V of Annex I to that order, which concerns the rules for the calculation of the maximum quantity of nitrogen contained in livestock manures which may be applied per annum in respect of each farm.

21

The Commission considered that the requirements laid down in Article 5(4) of Directive 91/676, read together with Annex II.A, points 1 to 5, Annex III.1, points 1 to 3, and Annex III.2 thereto, were not fully and properly implemented by the French Republic, and initiated the infringement proceedings provided for in Article 258 TFEU.

22

After giving formal notice to the French Republic that it should submit its observations, the Commission considered that the observations submitted were not satisfactory and issued, on 28 October 2011, a reasoned opinion, inviting the French Republic to adopt the measures necessary to comply with that opinion within a period of two months from the date of receipt.

23

The French Republic, by letter of 29 December 2011, replied to the reasoned opinion, arguing, inter alia, that the Commission’s objections had led it to undertake a comprehensive restructuring of the French legal provisions. Accordingly, under Decree No 2011-1257, the system based on departmental action programmes was replaced by a national action programme and by regional action programmes. Further, the order of 19 December 2011 approved the national action programme, so as to ensure that in the following agricultural year there would be an enhanced level of environmental protection. As regards the regional action programmes, because of the mandatory procedures for public consultation and environmental assessment, the French Republic claims that it is impracticable to bring them into force earlier than mid-2013.

24

Since the Commission was not satisfied with the French Republic’s reply to the reasoned opinion, it brought this action, although it withdrew the ground of complaint formulated in the reasoned opinion on the requirement laid down in Annex II.A, point 4, to Directive 91/676.

25

First, it must be recalled that Directive 91/676 seeks to create the instruments needed to ensure that waters in the European Union are protected against pollution caused by nitrates from agricultural sources (the judgment in Commission v Netherlands, C‑322/00, EU:C:2003:532, paragraph 41 and case-law cited).

26

In order to achieve those objectives, Member States are obliged, as laid down in Article 5(1) of Directive 91/676, to draw up and implement action programmes for designated vulnerable zones.

27

According to the eleventh recital in the preamble to Directive 91/676, those action programmes should include measures to limit the land application of all nitrogen-containing fertilisers and, in particular, to set specific limits for the application of livestock manure.

28

Under Article 5(4)(a) and (b) of Directive 91/676, those action programmes, for the implementation of which Member States are responsible, must, more specifically, contain certain mandatory measures listed in Annexes II and III to that directive.

29

Under Article 5(3)(a) and (b) of Directive 91/676, and Annex II.A, point 1, thereto, those action programmes are to take into account the best available scientific and technical data (see, by analogy, the judgment in Commission v Ireland, C‑418/04, EU:C:2007:780, paragraph 63, and the physical, geological and climatic conditions of each region (see, to that effect, Commission v Netherlands, EU:C:2003:532, paragraphs 136 and 155).

30

It must also be stated that although the directive allows the Member States a certain latitude as regards the precise methods of implementing the requirements of Directive 91/676 (see, to that effect, Commission v Netherlands, EU:C:2003:532, paragraph 46), they are, in all circumstances, obliged, as stated by the Advocate General in point 30 of her Opinion, to ensure that the objectives of Directive 91/676, and consequently the objectives of European Union policy in the area of the environment, are achieved, in accordance with the requirements of Article 191(1) and (2) TFEU.

31

Further, in accordance with well-established case-law of the Court, in relation to a directive which, like Directive 91/676, contains technical rules in the area of the environment, the Member States are under a particular duty, in order to satisfy fully the requirement of legal certainty, to ensure that their legislation intended to transpose that directive is clear and precise (see, to that effect, the judgments in Commission v United Kingdom, C‑6/04, EU:C:2005:626, paragraphs 21 and 26, and Commission v Belgium, C‑120/09, EU:C:2009:802, paragraph 27).

32

Last, according to the Court’s settled case-law, in proceedings for a declaration of failure to fulfil obligations, it is for the Commission to prove the existence of the alleged infringement and to provide the Court with the information necessary for it to determine whether the infringement is made out, and the Commission may not rely on any presumption for that purpose (the judgment in Commission v Cyprus, C‑340/10, EU:C:2012:143, paragraph 53 and case-law cited).

33

Consequently, in these proceedings, it is the task of the Court to determine whether the Commission has adduced the evidence necessary to demonstrate that the measures adopted by the French Republic in relation to the transposition of Directive 91/676 are not compatible with what is required by that directive.

34

The Commission raises six grounds of complaints in support of its action.

35

The Commission’s first ground of complaint, divided into five parts, concerns the minimum periods fixed by the order of 6 March 2001 during which the land application of various types of fertilisers is prohibited. In those respective five parts, the Commission’s complaint is that the French Republic:

36

By part (i) of this ground of complaint, the Commission claims that French law should provide rules prohibiting, during certain periods, the land application of any type of fertiliser, given that the uninterrupted land application of certain fertilisers throughout the year is harmful and makes it impossible to achieve the objectives of the directive, which are to prevent and reduce water pollution by nitrates from agricultural sources.

37

On the basis of the available scientific data, the Commission states that, even where the process of release of nitrogen contained in organic type I fertilisers is slow, such fertilisers carrying fewer risks than other types of fertilisers, the quantity of nitrogen released is however likely to contaminate waters by leaching and run-off. According to the Commission, the risks of water pollution are particularly significant during the autumn and winter periods, when nitrogen cannot be immediately taken up by plants because of low temperatures (lower than 5°C) and high rainfall which inhibits their growth.

38

By parts (ii) to (v) of its first ground of complaint, the Commission submits, for the same reasons as relied on in relation to part (i), that the periods of prohibition on land application of various types of fertilisers laid down by the French legislation are insufficient and should be lengthened in order to cover fully the periods in which there is a significant risk of water pollution by nitrogen not absorbed by plants.

39

The Commission adds that, for the reasons set out in Annex III to the reasoned opinion, the new periods of prohibition on land application established by the order of 19 December 2011 are not entirely compatible with the requirements of Directive 91/676. In its reply, the Commission sets out its criticism of the scheduled times for land application and of the classification of various types of fertilisers adopted in that order, and asks the Court to declare that the French Republic has thereby again failed to fulfil its obligations.

40

The French Republic contends, first, that, following the adoption of the order of 19 December 2011, the national legislation now provides for a minimum period of prohibition on land application of type I fertilisers in respect of autumn-planted arable crops and in respect of grasslands planted for more than six months.

41

Further, the French Republic states that the same order entirely altered the scheduled times laid down by the order of 6 March 2001, with the exception of the minimum periods of prohibition on land application of type II and III fertilisers in respect of grasslands planted for more than six months, those periods being, in its opinion, compatible with Directive 91/676.

42

According to the French Republic, the order of 19 December 2011 should be taken into account by the Court, since it represents a complete and directly applicable body of rules which was adopted before the expiry of the time-limit set by the Commission in the reasoned opinion. The French Republic states that while a number of measures in that order are not immediately applicable, that is because the nature of such measures is that they cannot be implemented in the course of an agricultural year. Moreover, the principle of legal certainty dictates that an adequate period should be allowed so that individuals can adapt themselves to the changes made.

43

The French Republic further contends, on the basis of the scientific data available to it, that a prohibition on land application of stable organic type I fertilisers, which release smaller quantities of nitrogen, slowly and gradually throughout the autumn and winter periods, may be counterproductive given that, because of the re-mineralisation of nitrogen in the ground, it may be desirable to spread such fertilisers in the autumn so that the nitrogen released by them may be usable by the plant when the plant is at the growing stage. Further, that practice would make it possible to eliminate dangers to the environment of fertilisation periods being concentrated in the spring and summer.

44

Further, the French Republic contends that there is a scientific consensus on the fact that grasslands for grazing, characterised by permanent vegetal cover, constitute systems in which there is low nitrogen leakage and which offer robust protection against water pollution caused, in particular, by certain organic type I fertilisers. Consequently, the period of prohibition envisaged by the Commission for grasslands planted for more than six months is excessively long.

45

Last, the French Republic considers that the criticisms set out by the Commission in its reply, as regards the order of 19 December 2011, are inadmissible, since, in its application, the Commission confined its complaints to the legal framework established by the order of 6 March 2001.

46

As regards the admissibility of the first ground of complaint relied on by the Commission in support of its action, it is clear that, in the application which initiated proceedings, the Commission restricted its criticism to the scheduled times laid down by the order of 6 March 2001. As regards the new scheduled times for land application, as laid down in the order of 19 December 2011, the Commission has not set out its criticism other than in the form of a mere reference to the assessment made in Annex III to the reasoned opinion.

47

Further, the criticism set out by the Commission in its application concerned either the failure to establish periods of prohibition or the establishment of periods of prohibition which it considered to be of insufficient duration. On the other hand, in its reply, the Commission directs its ground of complaint, first, to the failure to establish periods of prohibition which it considers appropriate, which are stated solely in Annex III to the reasoned opinion, and, secondly, to the inaccurate classification of various types of fertilisers, a matter to which there was no reference in the application.

48

It must be observed in that regard that, as follows from, in particular, Article 38(1)(c) of the Court’s Rules of Procedure, in the version in force when this action was brought, and the Court’s case-law relating to that provision, any application lodged under Article 258 TFEU must state the subject-matter of the dispute and a summary of the pleas in law on which the application is based and that statement must be sufficiently clear and precise to enable the defendant to prepare its defence and the Court to rule on the application (the judgment in Commission v Italy, C‑68/11, EU:C:2012:815, paragraph 51 and case-law cited). In accordance with settled case-law, that requirement is not satisfied if the Commission’s complaints are not set out in the application initiating the proceedings and simply appear by way of reference to the reasons set out in the letter of formal notice and in the reasoned opinion (the judgment in Commission v Greece, C‑375/95, EU:C:1997:505, paragraph 35 and case-law cited).

49

Further, even if Article 42(2) of those Rules of Procedure, in the version in force when the Commission’s statement in reply was lodged, permit, subject to certain conditions, the production of new pleas in law, a party may not alter the very subject-matter of the dispute in the course of proceedings (see, to that effect, the judgments in Commission v France, C‑256/98, EU:C:2000:192, paragraph 31 and Commission v Slovenia, C‑627/10, EU:C:2013:511, paragraph 44).

50

Consequently, the Commission’s first ground of complaint must be declared to be inadmissible, in so far as it complains that the French Republic committed infringements in additional to those set out, at least in sufficiently specific wording, in the application.

51

None the less, it must be stated that by directing, in the course of proceedings, its action against the provisions of the order of 19 December 2011 which do no more than reproduce the periods of prohibition imposed in the order of 6 March 2001 on the land application of type II and III fertilisers on grasslands planted for more than six months, the Commission did not alter the subject-matter of the dispute (see, to that effect, the judgments in Commission v Belgium, C‑221/03, EU:C:2005:573, paragraph 39, and Commission v France, C‑197/12, EU:C:2013:202, paragraph 26). The Commission’s request for a declaration of failure to fulfil obligations with reference to the provisions of the order of 19 December 2011 which do no more than reproduce the prohibition periods established by the order of 6 March 2001 is admissible.

52

First, according to the Court’s settled case-law, the question whether a Member State has failed to fulfil its obligations must be determined by reference to the situation prevailing in the Member State at the end of the period laid down in the reasoned opinion and the Court cannot take account of any subsequent changes (the judgment in Commission v Italy, C‑85/13, EU:C:2014:251, paragraph 31 and case-law cited).

53

The Commission’s reasoned opinion, which was dated 27 October 2011, was received by the French Republic on 28 October 2011 and the time-limit imposed on that Member State was set at two months from the date of receipt of that opinion. Consequently, the appropriate date for determining whether the French Republic has, as claimed, failed to fulfil its obligations is 28 December 2011.

54

Accordingly, although the order of 19 December 2011 was adopted prior to the expiry of the time-limit set in the reasoned opinion, account can be taken of the provisions of that order which had already entered into force on 28 December 2011, but not of those provisions which entered into force only after that date.

55

Under Article 2, section III, of that order, the provisions which establish the minimum periods during which the land application of various types of fertilisers is prohibited were not to enter into force until 1 September 2012, in other words after the expiry of the time-limit set in the reasoned opinion. It follows that the Court cannot take account of the alterations made by those provisions.

56

It must, secondly, be recalled that, in accordance with well-established case-law of the Court, infringement proceedings are based on the objective finding that a Member State has failed to fulfil its obligations under EU law, and consequently the Member State concerned cannot plead provisions, practices or situations prevailing in its domestic legal order to justify failure to comply with obligations and time-limits laid down by a directive (see, to that effect, the judgments in Commission v Ireland, C‑55/12, EU:C:2013:274, paragraph 45, and Commission v Czech Republic, C‑241/11, EU:C:2013:423, paragraph 48).

57

Consequently, the difficulties referred to by the French Republic as justification for the staggered application of the order of 19 December 2011 cannot, in this case, preclude the objective finding of an infringement of Directive 91/676.

58

As regards the substance of the ground of complaint, it must be observed that Article 5(4) of Directive 91/676, read together with Annex II.A, point 1, and Annex III.1, point 1, thereto, lays down the obligation to include in the action programmes rules covering the periods when the land application of fertilisers is either inappropriate or prohibited. The Court has previously held that the prohibition on land application in certain periods of the year is an essential provision of Directive 91/676, and that the directive does not provide for any derogations (see, to that effect, the judgment in Commission v Luxembourg, C‑526/08, EU:C:2010:379, paragraphs, 54, 55 and 57).

59

In this case, as regards parts (i) to (iv) of the Commission’s first ground of complaint, suffice it to state that the French Republic does not dispute that the scheduled times of land application established by the order of 6 March 2001 are not compatible with the requirements of Directive 91/676. The French Republic confines itself to pointing out that the new provisions of the order of 19 December 2011 have established or lengthened the minimum periods during which the land application of various types of fertilisers is prohibited.

60

As regards part (v) of the ground of complaint, it must be observed, that, in the written pleadings which it submitted to the Court, the French Republic contends that the organic type II fertilisers whose mineralisation is rapid and non-organic type III fertilisers must be applied in a period which is as close as possible to the period when plants are growing. However, the French Republic does not dispute that the potential of plant uptake over the whole of France comes to an end before 15 November or the fact that, in mountain areas, temperatures remain longer below the threshold (5°C) above which plants are capable of absorbing nitrogen.

61

Further, the argument presented by the French Republic with regard to stable organic type I fertilisers, summarised in paragraphs 35 and 36 of this judgment, cannot justify permitting the land application of type II organic fertilisers in the period when plants do not take up nitrogen. It is clear from material in the file submitted to the Court, which is not disputed by the French Republic, that the risk of water pollution associated with their land application during such a period is higher because of the greater proportion of nitrogen already in mineral form which those fertilisers contain. The same is necessarily true of type III mineral fertilisers.

62

Further, as observed in paragraph 29 of this judgment, it is clear that the specific climatic conditions of mountain areas must be taken into account when periods of prohibition on land application of various types of fertilisers are established.

63

Moreover, as regards the French Republic’s argument that grasslands offer permanent vegetal cover which guarantees the protection of waters against the leakage of nitrates, it must be stated that the scientific study on which that argument is based in no way discounts the risk of pollution associated with the land application of fertilisers when plants are not growing, that study saying no more, in fact, than that the losses of nitrogen in grasslands for grazing have been measured at a lower level.

64

In those circumstances, the Commission’s first ground of complaint must be held to be well founded.

65

By its second ground of complaint, divided into three parts, the Commission criticises the requirements laid down by the order of 6 March 2001 and by the departmental action programmes in relation to the storage of livestock manures. In those respective parts the Commission claims that:

66

In support of part (i) of this ground of complaint, the Commission claims that the national legislation contains no clear, specific and objective criteria which would enable farmers to calculate how much storage capacity they must have and the authorities properly to monitor the control of livestock manure. The Commission considers that a storage capacity expressed in months and weeks of production of livestock manure, accompanied by the definition of volumes of manure production according to animal categories, is the best means to that end.

67

In support of part (ii) of its second ground of complaint, the Commission observes that French law imposes no requirement that the storage capacities should incorporate a safety margin necessary for storage when the land application of livestock manure may be impossible because of particular climatic conditions. According to the Commission, minimum storage capacities for the equivalent of five months, as a minimum, for the departments of the Languedoc-Roussillon, Aquitaine, Midi-Pyrénées and Provence-Alpes-Côte d’Azur regions, and of six months, as a minimum, for the departments in other French regions, should be required.

68

In those parts (i) and (ii), the Commission also states that the DEXEL method for the assessment of storage capacity, provided for by the order of 19 December 2011, is not adequate, since it establishes complex rules which have to be individually applied to each holding by an accredited expert. Further, until 1 July 2016, storage capacities can continue to be calculated on the basis of the incorrect periods of prohibition on land application laid down by the order of 6 March 2001. In any event, the Commission claims that the real objective of that method is the adaptation of storage capacity to the economic and agronomic constraints of each holding and not to the periods of prohibition on land application.

69

By part (iii) of this ground of complaint, the Commission observes that almost all the departmental action programmes permit storage directly on the fields of solid straw manure for a period of ten months. According to the Commission, that form of storage over such a length of time, where there is no protection between the ground and the livestock manure and where the livestock manure is not covered, entails major risks of water pollution and should be prohibited. In its statement in reply, the Commission adds that the national authorities are incapable of monitoring the duration of that storage since the order of 19 December 2011 imposes no obligation on the farmer to record the date when the manure is placed on the fields.

70

The French Republic does not accept the Commission’s position. It asserts that the DEXEL method takes into consideration all the relevant parameters in order to obtain a reliable determination of the storage needs of each farm situated in a vulnerable zone, including climatic vicissitudes. The application of that method leads, consequently, to the identification of a minimum storage capacity which exceeds the capacity needed for storage over the longest period when land application is prohibited. According to the French Republic, the effect of imposing a six months storage capacity for the majority of French regions and five months for regions in the south of France would be that it would be impossible to take account of the diversity of farms and the diversity of soil and cultivation conditions in France.

71

As regards part (iii) of the Commission’s second ground of complaint, the French Republic submits, first, that it is inadmissible, in so far as it is directed against the very principle of permitting field storage of solid straw manure, the conditions under which that storage is carried out, and the arrangements for monitoring the applicable national rules, on the ground that the Commission confined itself, in the pre-litigation procedure, to criticism of the excessive length of the period during which that form of storage is permitted.

72

On the substance of part (iii), the French Republic argues that the order of 19 December 2011, which reproduces the requirements previously established by the departmental action programmes, provides that field storage may take place only after a two-month period of storage in buildings and on the condition that the manure is not subject to run-off. Those requirements ensure that any risk of water pollution can be prevented.

73

As regards the admissibility of the Commission’s second ground of complaint, it is clear that, in the reasoned opinion, the Commission did not criticise the very fact of permitting field storage of solid straw manure — and indeed it expressly accepted that such storage might take place provided that it was limited to a matter of weeks — or the fact that it was impossible for the authorities to determine the actual duration of this form of storage.

74

It must be recalled in that regard that, in accordance with the Court’s settled case-law, the subject-matter of an action brought under Article 258 TFEU is circumscribed by the pre-litigation procedure provided for in that provision and cannot, consequently, be extended in the course of the litigation. The Commission’s reasoned opinion and the action must be based on the same grounds and pleas, with the result that the Court cannot examine a ground of complaint which was not formulated in the reasoned opinion, which for its part must contain a cogent and detailed exposition of the reasons which led the Commission to the conclusion that the Member State concerned had failed to fulfil one of its obligations under the Treaty (see the judgments in Commission v Germany, C‑160/08, EU:C:2010:230, paragraph 43, and Commission v Spain, C‑67/12, EU:C:2014:5, paragraph 52).

75

Consequently, the Commission’s second ground of complaint, in so far as it complains that the French Republic committed infringements additional to those set out in the reasoned opinion, must be declared to be inadmissible.

76

On the other hand, as regards the conditions under which the field storage of solid straw manure is carried out, it must be observed that the ground of complaint was expressed in similar wording both in the pre-litigation procedure and in the proceedings before the Court. The Commission’s reasoned opinion already raised the risks of water pollution associated with this form of storage, precisely because of the conditions under which it is permitted, notwithstanding the information which had been sent by the French Republic relating to the requirements to be satisfied prior to such storage.

77

In those circumstances, it is clear that the Commission did not extend its ground of complaint on this point and did no more than give more detail, in its action, of its criticism with regard to those conditions and requirements, in order particularly to respond to the arguments put forward by the French Republic.

78

Accordingly, in so far as the Commission’s second ground of complaint is directed against the conditions under which field storage of solid straw manure is carried out, it must be declared to be admissible.

79

Further, it must be stated that, following paragraph 51 of this judgment, the Commission’s request, as submitted in its statement of reply, for a declaration of failure to fulfil obligations with reference to the provisions of the order of 19 December 2011 where those provisions do no more than reproduce the requirements of the departmental action programmes in relation to field storage of manure, is admissible.

80

It must first be observed that, under Article 2, section I.1, of the order of 19 December 2011, the provisions of that order relating to livestock manure storage vessels were to implemented as from the publication of that order, in other words before the expiry of the time-limit set by the reasoned opinion. Consequently, for the reasons stated in paragraphs 52 to 54 of this judgment, those provisions are to be taken into account in this action.

81

As regards the substance of this ground of complaint, it must be recalled that, under Article 5(4) of Directive 91/676, read together with Annex II.A, point 5, and Annex III.1, point 2, thereto, first, the action programmes must include rules as to the capacity and construction of storage vessels for livestock manures with the aim of preventing water pollution. Secondly, the storage capacity required must exceed that required for storage throughout the longest period during which land application in the vulnerable zone is prohibited, except where it can be demonstrated that any quantity of manure in excess of the actual storage capacity will be disposed of in a manner which will not cause harm to the environment.

82

As regards part (i) of the second ground of complaint, it must be stated that Annex I, section II.1, to the order of 19 December 2011 provides that any livestock unit situated in a vulnerable zone must possess storage vessels whose capacity must cover, at a minimum, taking into consideration possibilities of treating or eliminating manure without risk to water quality, the minimum periods of prohibition on land application and take account of additional risks linked to climatic conditions. The minimum storage capacity required must be expressed in weeks of manure storage.

83

For the calculation of the necessary storage capacities, Article 2, section I.1, of that order imposes an analytical method called DEXEL. It is apparent from the material in the file submitted to the Court that this analysis is carried out by an accredited expert with the cooperation of the farmer. It permits a calculation of storage capacities for solid manure and for liquid manure, adapted to the specific features of each farm and enabling farmers to undertake land application at the best time according to crop needs. It is also apparent from that material that the methodology and calculation method on which that analysis is based are defined in detail, with the inclusion of data on the monthly production of manure according to animal species.

84

Although the Commission claims that the DEXEL method is inadequate for the calculation of the storage capacity required, it must be said that the Commission does not demonstrate precisely how that method is inherently deficient.

85

In particular, the Commission’s criticism of the cooperation between the accredited experts and the farmers in the framework of the DEXEL method cannot be accepted. As stated by the Advocate General in point 65 of her Opinion, the involvement of experts with a view to the implementation of Directive 91/676 is in no way excluded by that directive.

86

Further, contrary to what is claimed by the Commission, it is not apparent from the material submitted to the Court relating to the DEXEL method that the calculation of storage capacities is contrary to the requirements of Directive 91/676.

87

Consequently, it must be held that part (i) of the Commission’s second ground of complaint is unfounded.

88

As regards part (ii) of the second ground of complaint, it is clear, first, that the order of 19 December 2011 provides that the design of storage vessels must take account of additional risks linked to climatic conditions. It follows that, contrary to what is claimed by the Commission, the storage capacities required by the national legislation must include a safety margin such as to permit an increased storage volume when land application is impossible for climatic reasons.

89

Further, as regards the minimum storage periods which, according to the Commission, should be imposed in the various regions of France, suffice it to observe, first, that it is apparent from the scientific study submitted by the Commission that, in the regions of France situated in the Mediterranean soil area, a storage capacity of only four months should be sufficient.

90

Secondly, it is also apparent from the file submitted to the Court that factors peculiar to each individual livestock unit, such as the type of livestock manure produced and the crops planted, are likely to influence the storage capacities required. The scientific data referred to by the French Republic in that regard, which is not criticised by the Commission, shows, in particular, that the risks of pollution associated with livestock rearing systems which produce only stable type I organic fertilisers, particularly where grasslands for grazing are concerned, are less high.

91

Last, it must be observed that Article 2, section I.2, of the order of 19 December 2011 permits, during a period which may extend until 1 July 2016, the calculation of storage capacities on the basis of the scheduled times of prohibition on land application laid down by the order of 6 March 2001, which, as held in paragraph 64 of this judgment, do not comply with the requirements of Directive 91/676. The Commission is therefore correct in its claim that the French Republic has not established rules which ensure that holdings are equipped with sufficient storage capacity.

92

Accordingly, it must be held that part (ii) of the Commission’s second ground of complaint is well founded, in so far the Commission claims that until 1 July 2016 it will still be possible for the calculation of storage capacities to take account of scheduled times of prohibition on land application which are not compatible with the requirements of Directive 91/676.

93

As regards part (iii) of the Commission’s second ground of complaint, it is apparent from the material in the file submitted to the Court, which is not disputed by the French Republic, that, following its storage in buildings for the first two months, solid straw manure continues to release nitrogen, albeit slowly and gradually. It follows, further, that the phase of net mineralisation of nitrogen released in the soil, during which the risk of pollution associated with such fertilisers is lower, is temporary. Accordingly, where fertiliser is applied in the autumn, that phenomenon persists as a general rule until the end of winter.

94

Consequently, given that the storage of manure directly on the fields and uncovered is permitted for a maximum period of ten months, which period may be longer than the phase of net mineralisation of nitrogen, the risk of water pollution associated with that form of storage cannot be eliminated.

95

In the light of the foregoing, it must be held that part (iii) of the second ground of complaint raised by the Commission in support of its action is well founded.

96

In those circumstances, the Commission’s second ground of complaint must be held to be well founded, in so far as the national legislation, first, provides that until 1 July 2016 it will still be possible for the calculation of storage capacities to take account of a schedule of prohibition on land application which is not compatible with the requirements of Directive 91/676 and, secondly, permits field storage of solid straw manure for a period of ten months.

97

By its third ground of complaint, the Commission’s criticism of the French Republic is that there are no rules enabling farmers and monitoring authorities to calculate exactly how much nitrogen can be applied to the land in order to ensure balanced fertilisation.

98

In support of that ground of complaint, the Commission maintains that, although the order of 6 March 2001 put in place a method, called the estimated balance method, to assess the quantity of nitrogen to be supplied, the majority of the departmental action programmes either do not determine all the required calculation factors (the nitrogen needs of each crop and grassland, the effectiveness of nitrogen in livestock manure, the nitrogen contained in the soil and in livestock manures, etc.), or present those factors in such a complicated way that correct application is not at all guaranteed. According to the Commission, the establishment of quantified maximum limits on total nitrogen additions in respect of the various crops would make it possible to reduce the difficulties in applying that method and to satisfy the requirement of legal certainty.

99

The Commission also states, in its reply, that the estimated balance method was defined by the order of 19 December 2011 only in its basic principles, while leaving the definition of regional points of reference for the operational application of that method to the regional prefects, as advised by regional groups of nitrates experts. The Commission then submits a number of criticisms with regard to the requirements laid down by that order and by the orders of the regional prefects implementing it.

100

The French Republic considers that the estimated balance method adequately ensures balanced nitrogen fertilisation since it permits a determination of standards for use which limit at the source the quantity of fertilisers applied to the land by taking account of the particular soil and cultivation features of each farm.

101

Further, the French Republic contends that the effect of alterations introduced by the order of 19 December 2011 is that it is possible to ensure a correct application of the principle of balanced fertilisation. The French Republic states in that regard that that order now refers expressly to the estimated balance calculation method and provides links to documentation accessible on line which describes that method in detail. Further, that order establishes the requirements necessary for the calculation of the balanced nitrogen quantity, which are directly binding on farmers, there being no need to wait for the adoption of prefectoral orders on operational references at the regional level.

102

As regards the admissibility of the Commission’s third ground of complaint, it must be observed that the Commission claims, for the first time in its statement in reply, that the French Republic committed infringements in relation to the provisions of the order of 19 December 2011 and to the prefectoral orders which do no more than repeat the content of the provisions of the order of 6 March 2001.

103

Consequently, in so far as, by that ground of complaint, the Commission claims that the French Republic committed additional infringements which are not mentioned in either the reasoned opinion or the application, the Court must, following paragraphs 49 and 74 of this judgment, reject that ground of complaint as being inadmissible.

104

First, it is clear that, under Article 2, section II, of the order of 19 December 2011, the provisions of that order imposing obligations on farmers in relation to the land application of nitrogen fertilisers in vulnerable zones were not to enter into force until 1 September 2012, in other words after the expiry of the time-limit set in the reasoned opinion.

105

Further, it is undisputed that, on the expiry of that time-limit, the regional points of reference, required for the implementation of the provisions of that order on the calculation of the quantity of nitrogen to be supplied by fertilisers according to the estimated balance method, had not yet been determined.

106

It follows that, for the reasons set out in paragraphs 52 to 54 of this judgment, there is no need to examine whether the modifications made by that order might constitute a valid performance of the obligations stemming from Annex III.1, point 3, to Directive 91/676.

107

For the remainder, it must be recalled that, under Article 5(4) of Directive 91/676, read together with Annex III.1, point 3, thereto, the measures to be included in action programmes are to extend to rules concerning the limitation of the land application of fertilisers based on a balance between the foreseeable nitrogen requirements of the crops and nitrogen supplied to the crops from the soil and by fertilisers.

108

In this case, it is clear that, while it is apparent from the documents submitted to the Court that the reasoning which underlies the estimated balance method should, in principle, result in an optimal supply of nitrogen to each crop, it remains the case that the French Republic itself acknowledges that the provisions of the order of 6 March 2001 relating to the balanced nitrogen fertilisation do not make it possible to ensure the full application of Annex III.1, point 3, to Directive 91/676 in a sufficiently clear and precise manner.

109

It must be observed in that regard that, both in the course of these proceedings and in the pre-litigation procedure, the French Republic has done no more than refer to the changes made by the order of 19 December 2011 in order to render the application of the estimated balance method ‘simple and intelligible’ and to enable farmers and monitoring authorities to calculate correctly the quantity of nitrogen which can be applied to the land in order to guarantee the balanced fertilisation aimed at by the directive, which is sufficient evidence that that was not the case when the order of 6 March 2001 was in force.

110

Consequently, the third ground of complaint relied on by the Commission in support of its action must be held to be well founded.

111

First, it must be stated that the Commission, in its reply, after taking note of the arguments put forward by the French authorities in their statement in defence, decided to withdraw part of its fourth ground of complaint, in so far as that complaint concerned the nitrogen discharge values established for liquid pig manure, which, consequently, is no longer part of the subject-matter of this action.

112

By its fourth ground of complaint, divided into eight parts, the Commission claims, on the basis of scientific studies, that the nitrogen discharge values laid down by the circular of 15 May 2003 in respect of various types of animals, to which a large number of the departmental action programmes refer, were calculated on the basis of amounts of animal-excreted nitrogen which were inaccurate or on coefficients for the loss of nitrogen by volatilisation which were overestimated. Consequently, the effect of that circular is that it is impossible to ensure compliance with the limit of land application of livestock manure fixed by Directive 91/676 at 170 kilogrammes of nitrogen per hectare per annum. The parts (i) to (viii) within the Commission’s fourth ground of complaint are respectively concerned with:

113

By part (i) of its fourth ground of complaint, the Commission considers, first, that the nitrogen discharge value established for dairy cows is based on a quantity of excreted nitrogen which takes no account of the different levels of milk production, since the nitrogen contained in livestock manure varies according to the animal’s milk production rate and several regions in France are characterised by intensive production. Further, that value is based on a volatilisation coefficient which is excessively high, since an average volatilisation coefficient should be estimated at 24%.

114

In addition, the Commission claims that the transitional provision laid down in Annex II, section B, of the order of 19 December 2011, pursuant to which, for the period from 1 September 2012 to 31 August 2013, an interim value is to apply to dairy cow livestock units which have more than 75% of the area under grass in the main forage area, results in the land being overfertilised and in a derogation from the upper limit of 170 kilogrammes of nitrogen per hectare per annum.

115

By part (ii) of its fourth ground of complaint, the Commission claims that the volatilisation coefficient chosen for other cattle is too high, since scientific data adopts a volatilisation coefficient of less than 21%. In its statement in reply, the Commission also calls into question the quantities of excreted nitrogen chosen by the French Republic for the establishment of those values.

116

By part (iii) of this ground of complaint, the Commission considers that nitrogen discharge values should also be established for solid pig manure.

117

In part (iv) of its fourth ground of complaint, the Commission states that the volatilisation coefficient proposed in the scientific literature for liquid manure is 30%. Accordingly, as regards poultry producing liquid manure, the values established by the French legislation entail a significant underestimation of the spreadable nitrogen content of the manure.

118

By parts (v) and (vi) of this ground of complaint, the Commission claims that the volatilisation coefficients chosen for sheep and goats are excessively high, since coefficients of 9.5% are mentioned in scientific studies.

119

As regards part (vii) of its fourth ground of complaint, the Commission argues that a volatilisation coefficient 13.1% lower than that established by the national legislation is maintained by the scientific literature as regards horses.

120

Last, by part (viii) of this ground of complaint, the Commission argues that the volatilisation coefficient chosen by the national legislation in respect of rabbits is also too high. In that regard, the Commission states that coefficients of 28% and 44% are maintained in various scientific studies.

121

The French Republic contends, first, that the nitrogen discharge values recalculated by the Commission by means of the application of the volatilisation coefficients which it deems appropriate are incorrect, since those coefficients should only be applied to the fraction of nitrogen discharged in buildings or during storage. Yet the Commission has also applied them to the quantity of nitrogen discharged in the open.

122

The French Republic considers, further, that the Commission’s criticism as regards the quantities of excreted nitrogen laid down in respect of cattle other than dairy cows is inadmissible since it is relied on for the first time in the statement in reply.

123

The French Republic also states that the order of 19 December 2011 now provides for a lower volatilisation coefficient, 25%, as regards dairy cows and also establishes nitrogen discharge values applicable to solid pig manure.

124

Last, the French Republic observes that the volatilisation coefficients chosen by the French legislation are based on the work of the Steering Committee for environmentally friendly agricultural practices (Corpen) and were obtained on the basis of comparative methods, which consist of attributing to volatilisation the difference between nitrogen excreted by animals and nitrogen measured in excrement out of buildings or storage. Those methods are better suited to the calculation of nitrogen discharge values than the direct measurement methodology on which the studies submitted by the Commission are based, which analyse air flow and gas content entering and leaving buildings and storage installations. The French Republic claims that, in any event, the available scientific data on nitrogen gas emissions produced by livestock manure show very great variations in the values relating to those emissions.

125

As regards the admissibility of the fourth ground of complaint relied on by the Commission, it must be stated, first, that the criticism concerning the transitional provision laid down in Annex II, section B, to the order of 19 December 2011, on the production by dairy cows of nitrogen capable of land application, was not stated in the reasoned opinion. Further, although, in its application initiating the proceedings, the Commission expressly stated that it did not dispute the quantities of excreted nitrogen chosen for other cattle, in its statement in reply the Commission does call into question those elements of calculation.

126

Consequently, in so far as, by that ground of complaint, the Commission criticised the interim value established for dairy cows by the transitional provision in Annex II, section B, to the order of 19 December 2011, and the quantities of excreted nitrogen established for other cattle by the circular of 15 May 2003, that ground of complaint must, for the reasons set out in paragraphs 49 and 74 of this judgment, be rejected as being inadmissible.

127

On the other hand, following paragraph 51 of this judgment, the Commission’s request, in accordance with the request to that effect in its statement in reply, for a declaration of failure to fulfil obligations in relation to the provisions of the order of 19 December 2011 which restated the nitrogen discharge values established for cattle, other than dairy cows, and for poultry, sheep, goats, horses and rabbits, is admissible.

128

First, it is clear that, under Article 2, section II, of the order of 19 December 2011, the provisions of that order on the rules for the calculation of the maximum quantity of nitrogen contained in livestock manure which can be applied to the land annually for each farm were to enter into force only on 1 September 2012, in other words after the expiry of the time-limit set by the reasoned opinion. That is also necessarily true of the standard nitrogen excretion rates per animal, laid down by the same order to permit the implementation of those provisions. Consequently, as has been stated in paragraphs 52 to 54 of this judgment, the Court cannot have regard to the modifications introduced by the order of 19 December 2011.

129

For the remainder, it must be recalled that Article 5(4) of Directive 91/676, read together with Annex III.2 thereto, imposes the obligation to include in action programmes rules concerning the limitation of land application of fertilisers designed to ensure that ‘for each farm or livestock unit, the amount of livestock manure applied to the land each year, including by the animals themselves, shall not exceed a specified amount per hectare’. That limitation corresponds to the quantity of manure containing up to 170 kilogrammes of nitrogen, although the Member States have, under the conditions defined by Annex III.2(a) and (b) to Directive 91/676, the option of permitting a different quantity of manure.

130

As is apparent from the eleventh recital in the preamble of that directive, the fixing of specific limits for the land application of livestock manure is of particular importance to the achievement of the objectives of reduction and prevention of water pollution by nitrates of agricultural origin.

131

Under Annex III.3 to that directive, the quantities of livestock manure which may be applied to the land may be calculated on the basis of the number of animals. To that end, the Member States must, as stated in paragraph 29 of this judgment, take into account the best available scientific and technical knowledge and also the physical, geological and climatic conditions of each region.

132

In this case, under Annex II, point 1, to the order of 1 August 2005, the calculation of the animal-produced nitrogen available on the farm is to be carried out by multiplying the number of animals by the values for the production per animal of nitrogen capable of land application. It is common ground that those values are determined by deducting, from the gross amounts of nitrogen excreted by the animals, nitrogen which is volatilised, both when the animals are inside buildings and when the manure is in storage, by means of the application of volatilisation coefficients.

133

In the light of the foregoing, it must be held, first, that the errors committed by the Commission when it recalculated the nitrogen discharge values, as it itself recognises in its statement in reply, take nothing away from its criticism as regards the gross quantities of excreted nitrogen and the coefficients for the loss of nitrogen by volatilisation established by the national legislation in respect of the various types of animals. That conclusion is not disputed by the French Republic which, on that point, does no more than refer to the incorrect application of the coefficients in question to the overall quantity of nitrogen excreted by the animals.

134

Further, as regards parts (i) and (iii) of the Commission’s fourth ground of complaint, suffice it to hold, first, that the French Republic admits, when it points out the changes made in that regard by the order of 19 December 2011, first, that, before the adoption of that order, it established a volatilisation coefficient for dairy cows which was excessively high and, secondly, that it failed to establish nitrogen discharge values for solid pig manure.

135

As regards, secondly, the failure to take into account the rate of milk production when calculating the gross quantity of nitrogen excreted by dairy cows, it must be noted that the Commission’s argument has not been disputed by the French Republic, and that the order of 19 December 2011 now provides for several levels of production of nitrogen capable of land application corresponding to milk production.

136

Last, as regards parts (ii) and (iv) to (viii) of this ground of complaint, which can be examined together, it must be stated that the Commission relies on the technical data to be found in a number of scientific studies as the basis for its criticism of the volatilisation coefficients chosen by the national legislation on the basis of the Corpen conclusions.

137

The French Republic, which does not dispute the conclusions of the studies relied on by the Commission, does no more than plead, in essence, first, that there are flaws in the direct measurement methodology on which those studies rely for the calculation of volatilisation coefficients applicable to livestock units. Secondly, the French Republic points to the fact that the volatilisation coefficients do not seem capable of being determined exactly from a scientific perspective, and that uncertainty is reflected in variations in the volatilisation coefficients available in the scientific literature.

138

As regards, first, the adequacy of the direct measurement methodology, it must be observed that the objections of the French Republic cannot, as such, call into question the relevance of the volatilisation coefficients maintained by the Commission. It is apparent from the material submitted to the Court that both that methodology and the balance method are based on empirical work which takes into account only the specific context of each type of livestock unit under study. In addition, the latest re-evaluation of Corpen references does not suggest any preferred methodology.

139

Secondly, as regards the margin of fluctuation of volatilisation data apparent in the scientific publications, it must be emphasised that it is very clear from the wording of Annex III.2 to Directive 91/676 that that provision requires that the specific limit laid down for the land application of livestock manure, in other words 170 kilogrammes of nitrogen per hectare per annum, should be systematically respected by every farm or livestock unit, including where, in accordance with Annex III.3, the Member States decide to calculate that limit by reference to the number of animals.

140

Further, it is apparent from the material submitted to the Court that one explanation of the variations in the volatilisation coefficient values available in the scientific literature may be the heterogeneity in conditions of livestock rearing and climatic contexts which were the subjects of the studies carried out, and the French Republic, notably at the hearing, stressed the diversity of French livestock units.

141

In those circumstances, as stated by the Advocate General in points 123 to 126 of her Opinion, only by establishing volatilisation coefficients on the basis of the data which estimates the loss of nitrogen by volatilisation at the lowest percentage is it possible to ensure that the limit laid down by Directive 91/676 for the land application of manure is properly observed by all French livestock units.

142

Given that the French Republic established volatilisation coefficients for cattle other than dairy cows, and for poultry, sheep, goats, horses and rabbits, which were significantly higher than those adopted by the Commission on the basis of scientific data the accuracy of which is not challenged by the French Republic, it must be held that those volatilisation coefficients as established by the national legislation do not satisfy the requirements of Directive 91/676.

143

In the light of the foregoing, the Commission’s fourth ground of complaint in support of its action must be held to be well founded.

144

By its fifth ground of complaint, the Commission’s criticism of the French Republic is that there are no satisfactory rules, containing clear, precise and objective criteria, concerning the conditions for the land application of fertilisers on steeply sloping ground. According to the Commission, in order to ensure a proper implementation of the requirements of Directive 91/676, the national legislation ought to have defined the percentages of slope above which the land application of fertilisers is prohibited.

145

The French Republic contends that the order of 6 March 2001 prohibited land application on steeply sloping ground where such application entailed risks of run-off from the area of land application. The French Republic submits, further, that risks of water pollution depend not only on the degree of the slope but also on a host of other factors, such as the consistency of the slope, the nature of the plant cover and the direction of planting, the nature of the soil, the shape of the area of land, how and in what direction the ground has been worked, and the type of manure. Consequently, the prohibition of land application exclusively based on the extent of the slope’s gradient is inadequate.

146

The French Republic adds that the order of 19 December 2011 provides for rules relating to the conditions for land application concerning water courses which, read together with the prohibition on land application on steeply sloping ground, contribute to the realisation of the objectives of the directive.

147

First, it must be observed that, under Article 2, section III, of the order of 19 December 2011, the provisions of that order relating to conditions for land application concerning water courses were not to enter into force until 1 September 2012, in other words after the expiry of the time-limit set by the reasoned opinion. It follows that, for the reasons stated in paragraphs 52 to 54 of this judgment, the Court cannot have regard to the provisions of that order relating to the conditions for land application concerning water courses.

148

As regards the substance, it must be observed that, under Article 5(4) of Directive 91/676, read together with Annex II.A, point 2, and Annex III.1, point 3(a), to that directive, action programmes must contain rules covering the conditions for the land application of fertilisers on steeply sloping ground.

149

Further, as stated above in paragraph 31 of this judgment, the Member States are under a particular duty to ensure that their legislation intended to transpose Directive 91/676 is clear and precise.

150

It must in that regard be observed, first, that the Commission claims, without challenge by the French Republic on the point, that some departmental action programmes contain no rule relating to the conditions for land application of fertilisers on steeply sloping ground, whether based on the percentage of slope or on any of the various factors which the French Republic considers should be taken into account. Further, a substantial number of departmental action programmes do no more than reproduce the general principle, laid down by the order of 6 March 2001, that land application must not take place in circumstances as a result of which there is run-off from the area of land application.

151

Secondly, it is apparent from examination of the relevant provisions of the order of 6 March 2001 that that order, primarily, merely prohibits land application of fertilisers on steeply sloping ground and, secondarily, provides that the action programmes must specify the situations where the prohibition is applicable, taking account of risks of run-off from the area of land application or, otherwise, the slope percentage above which land application is prohibited.

152

It is clear that the generality of those provisions is such that they are incapable of meeting the deficiencies of the action programmes and, therefore, of ensuring the full application of the provisions in Annex II.A, point 2, and Annex III.1, point 3(a), to Directive 91/676, sufficiently clearly and precisely, in accordance with the requirements of the principle of legal certainty.

153

In those circumstances, the Commission’s fifth ground of complaint must be held to be well founded.

154

By its sixth ground of complaint, the Commission, on the basis of scientific data, criticises the French Republic for having failed to adopt rules prohibiting the land application of any type of fertilisers on frozen or snow-covered ground when such land application entails considerable risks of run-off and leaching. The Commission states, in that regard, that the order of 6 March 2001 provides that the land application of type I and III fertilisers on ground which is substantially frozen, and the land application of type I fertilisers on snow-covered ground, must be regulated. Further, according to that order, the land application of any fertiliser is permitted on ground which is only superficially frozen as a result of a 24-hour cycle of freezing and thaw. Last, some farms have the option of spreading on frozen ground solid straw manure and composted livestock manure.

155

The French Republic’s response to this argument is that Directive 91/676 does not require that the land application of fertilisers on ground which is snow-covered or frozen should be systematically prohibited, but only that it be regulated. The French Republic accepts that, given the risks which the land application of fertilisers in such conditions is likely to represent, such operations must be subject to substantial restrictions. However, the French Republic considers that the order of 6 March 2001 establishes such restrictions, since the land application of type II fertilisers on frozen ground and the land application of type II and III fertilisers on snow-covered ground are prohibited in all circumstances.

156

Article 5(4) of Directive 91/676, read together with Annex II.A, point 3, and Annex II.1, point 3(a) and (b), to that directive, requires that the Member States adopt measures designed to limit land application where ground is frozen or snow-covered.

157

Further, as was stated in paragraph 29 of this judgment, under Article 5(3)(a) of that directive, action programmes must take account of the best available scientific knowledge.

158

In this case, as stated by the Advocate General in point 144 of her Opinion, according to the scientific study submitted to the Court by the Commission, the conclusions of which are not disputed by the French Republic, the land application of fertilisers on frozen or snow-covered ground must be prohibited in all circumstances. That is because frozen ground and snow-cover limit the movement of nutrients in the soil and substantially increase the risk that those nutrients are later carried to surface waters, inter alia by run-off.

159

Further, the risks of pollution to be feared in the event of land application on frozen or snow-covered ground are no less where the ground is only superficially frozen, through the effect of a freeze-thaw cycle over a period of 24 hours. On the contrary, it is apparent from the scientific study referred to in the preceding paragraph that freeze-thaw cycles have a significant impact on mineralisation rates, since the freezing of thawed ground encourages nitrogen mineralisation.

160

Consequently, the Commission’s sixth ground of complaint must be held to be well founded.

161

In the light of all the foregoing, the Court must hold that, by not adopting the measures necessary to ensure the full and correct implementation of all the requirements imposed on it by Article 5(4) of Directive 91/676, read together with Annex II.A, points 1 to 3 and 5; Annex III.1, points 1 to 3, and Annex III.2, to that directive, the French Republic failed to fulfil its obligations under that directive, in so far as, in the national legislation adopted in order to ensure the implementation of that directive:

162

The action is dismissed for the remainder.

163

Under Article 138(1) of the Rules of Procedure of the Court of Justice, the unsuccessful party must be ordered to pay the costs if they have been applied for in the other party’s pleadings. Pursuant to Article 138(3) of those rules, the parties are to bear their own costs where each party succeeds on some and fails on other heads. However, if it appears justified in the circumstances of the case, the Court may order that one party, in addition to bearing its own costs, pay a proportion of the costs of the other party.

164

In this case, since the French Republic has essentially been unsuccessful and the Commission has applied for costs, the French Republic must be ordered to pay all the costs.

On those grounds, the Court (Second Chamber) hereby