Marine terminals usually have a wastewater facility to separate and 

 treat contaminated ballast water. Oil vessels require tank cleaning and 

 debal lasting whenever new cargo is to be loaded which will not tolerate 

 residues from a previous cargo. It is estimated that 0.2 to 0.4 percent 

 of an oil shipment will adhere to the storage tank walls [7]. Heated 

 sea water is used to clean the cargo tanks. Ballast water effluent 

 limitations are imposed by EPA (Table 9). The average tanker 



Table 9. Effluent Limitations for Ballast Water in Pounds/ 

 Million Gallons of Flow (Using Best Available Technology 

 Economically Applied) (Source: Reference 10) 



Characteristics 



Maximum for 

 Any One Day: 



Average Daily Values 

 for 30 Consecutive 

 Days Shall Not Exceed; 



Biological Oxygen Demand (5 day 

 Test) 



Total suspended solids 



Chemical Oxygen Demand 



Oil and Grease 



0.088 



0.084 



0.32 



0.018 



0.071 



0.071 



0.26 



0.014 



takes on about 40 percent of its capacity in ballast water. Thus, 

 a 20,000 DWT tanker with a capacity of 140,000 barrels takes on about 

 56,000 barrels of ballast, which then is contaminated with about 280 to 

 560 barrels of the original tanker cargo [7]. 



Subproject: Marine Transport of Oil (SP-19) 



Disturbing Activity: Marine oil transport 



Both spills and leaks may occur during oil and gas transfer between 

 vessels and storage tanks at a marine terminal. Although spills are 

 usually due to human error, they may also result from equipment and 

 structural failures in such components as manifolds, pumps, and valves. 

 Other potential points of structural and equipment failures include: 

 storage tank rupture or leak, hose rupture, and line or pipe leak. 



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