European pipelines in 1993 spilled as much crude oil and petroleum products as in any year since 1971, when statistics first began to be reported.
Final cost of cleanup will exceed $10 million, by far the most ever spent by western European oil pipelines operating on land. This cost figure is only preliminary: costs for three spills totaling nearly 2,600 cu m (approximately 16,380 bbl; 43.6% of total spilled) had not been reported through November 1994.
All this is according to Concawe, Brussels (Conservation of Clean Air and Water, Europe), the oil companies' European organization for environmental and health protection. Figures for 1993 are the most recent compiled.
Ten incidents of oil spills from pipelines occurred in 1993, compared with seven for 1992 and an average of 12.7/year since 1971. Nine spills were along the lines; one was from a pump station.
Net loss of oil into the environment was 2,536 cu m (15,977 bbl). Gross amount of spills totaled 5,965 cu m (37,580 bbl), most in the period 1989-1993 (Table 1) (25269 bytes).
SYSTEM EXPANDS
Total length of oil industry cross-country pipelines operating in Western Europe at the end of 1993 was 21,600 km (13,414 miles), up from nearly 19,000 km in 1989.
This was reported in Concawe's survey by 63 respondents that operate a network of approximately 215 separate lines. A new pipeline of nearly 100 km began operating in Spain in 1993.
In all, 601 million cu m (3.8 billion bbl) of crude oil and refined products moved through the pipeline system. Total traffic volume was 104 billion cu m-km, of which products amounted to 25.4 billion cu m-km.
Concawe categorizes spills of more than 1 cu m according to cause. For 1993, there were two spills from mechanical failure; none from operational causes; three from corrosion; one from natural hazards; and four from third-party activity.
The ten incidents spilled 5,965 cu m, as stated, with 3,429 cu m (57%) recovered. Concawe reports the combined cost of pipeline repair and cleanup to be approximately 8.8 million ECUs (1993: $9.992 million) for only 3,371 cu m of spill for which costs were reported.
INCIDENTS
Table 2 (13592 bytes) shows spills since 1971, the first year for which Concawe reported data, compared with those for 1993.
As of November 1994, cleanup and repair were under way for the largest of the 1993 spills and one of the largest Concawe has recorded.
A split in a products pipeline (20 in., 0.350-in. W.T., Grade X-52) attributed to third-party damage progressed as a result of fatigue.
More than 3,050 cu m accumulated as an initially small rate of leaking expanded during several months until the loss was detected by installed measurement controls. As much as 1,600 cu m of product were expected to be recovered and safely disposed of.
Recovery involved scavenging the subsurface oil as it collected in boreholes and soil venting supplemented by bioremediation.
Final costs for cleanup are estimated at nearly $2.3 million (1993).
In another serious incident, a crude oil pipeline (20 in., 0.315-in. W.T., Grade St 52-3/E 360.7) leaked 2,000 cu m from a split due to internal corrosion. The failure was near a motorway crossing.
Cleanup and extensive soil removal have led to removal of approximately 1,500 cu m of the spill. No final costs were available as of November 1994 when Concawe put together its report for 1993.
These two incidents in 1993 accounted for more than 5,000 cu m of the 5,965 cu m spilled.
Elsewhere, at a river crossing, internal corrosion in a bypass loop line of another products pipeline (6 in., 0.200-in. W.T., 5L X-42) leaked an estimated 580 cu m. Earlier in-line inspection of the main line had failed to detect a problem, but the bypass could not be inspected.
A later right-of-way inspection by the operator revealed the leak that lost 500 cu m permanently to the soil. The dead leg formed by the by-pass has now been eliminated.
Final cleanup costs were not reported.
In another spill, a 34 in., 0.310-in. W.T., Grade 5LX X52 line spilled 248 cu in of crude oil as a result of mechanical failure in the line. A routine pressure test uncovered the leak that apparently was a mechanical failure due to a metallurgical blemish from the time of the pipe's manufacture.
The blemish had focused the stresses from operating pressure fluctuations throughout 31 years' service. The resulting fatigue failure caused a longitudinal split.
The failure occurred during pressure testing of the pipeline to 110% of maximum operating pressure for a statutory 10-year test.
Costs for cleaning up this spill were estimated at $1,356,000.
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