4.14 INDUSTRIAL WASTEWATER SYSTEMS - SUBPROJECT 14 



Process wastewater from industries sited in coastal areas have 

 potential impacts that range from relatively minor disturbances to major 

 disruptions caused by excessive discharge of toxic chemicals. 



Oil spills and other catastrophic releases often have prominence in 

 the public eye, but perhaps a more damaging form of pollution is the 

 chronic release of industrial contaminants that insidiously degrade 

 coastal ecosystems. There may be no large fish kills or other dramatic 

 evidence of harm, but only a pervasive and continuous degradation of the 

 system manifested by an apparent and somewhat mysterious decline in its 

 carrying capacity. Industrial waste materials in plant effluents may 

 alter carrying capacity of the coastal ecosystem in a variety of ways. 



4.14.1 Summary 



This section is concerned with routine discharges of process waste- 

 water from OCS-related industries; mainly from refineries, petrochemical 

 plants, gas processing plants, and partial processing plants. It does 

 not deal with accidental releases or spills. (Oil spills are treated in 

 Section 4.19; cooling water in Section 4.15; sewage in Section 4.10; and 

 stormwater runoff in Section 4.12). 



Industrial wastewater which contains chemicals added in the treatment 

 processes or contaminated with material being processed is referred to as 

 process water. Process water from the facilities which support OCS 

 activities contains oil and oil-coated solids. In addition, the electrical 

 method of crude desalting produces wastewater containing sulfides, 

 suspended solids, phenols, and ammonia, all at higher tempera- 

 tures. Crude oil fractionation oroduces sulfides, chlorides, and 

 phenols. The thermal cracking process, hydrotreating, lube oil finishing, 

 and other operations produce wastewater containing phenols, oils, sulfur 

 compounds, arrmonia, and stable oil emulsions [127]. 



The quality and volume of wastewater discharged will depend upon the 

 physical and chemical characteristics of the product's rate of processing, 

 plant design and complexity, and the degree of treatment of effluent. 



Particular characteristics of aquatic ecosystems govern their 

 capacities to absorb impacts. The probability that pollutants discharged 

 into any water body will accumulate to damaging levels is controlled by 

 water basin configuration. The contamination potential of a water body 

 is a function of its capacity (length, width, and depth) and the rate of 

 exchange (flushing) of its waters. These factors control the rate of 

 dilution and dispersion of the contaminant and its biological and 

 physical storage. 



Substances are termed "toxic" when their physical or chemi- 

 cal properties interfere with normal biological functions. The 



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