withdrawal can lead to overpumping of aquifers, causing land subsidence 

 and, in coastal areas, saltwater intrusion. According to one estimate, 

 petrochemical plant water supply needs can be reduced by up to 50 percent 

 by 1985 through the adoption of water recycling methods, and process 

 techniques requiring lower water volumes [25]. 



New petrochemical plants that propose to draw cooling water from 

 surface waters--estuaries, lakes, or rivers'-normally are required to use 

 closed cycle systems to reduce water consumption, to prevent disturbances 

 to critical water areas, and to prevent cooling water from coming in 

 contact with hydrocarbons. 



Subproject: Stormwater Systems (SP-12) 



Disturbing Activity: Stormwater conveyance 



Runoff may be contaminated with heavy metals, detergents, paints, 

 spilled fuels, and other toxic chemicals. Special runoff collection 

 systems may be provided for areas with the most contamination. This 

 runoff then can be treated and discharged along with process water. 

 Standard stormwater runoff systems are provided for areas of lesser 

 pollution potential, and may require retention ponds or special holding 

 tanks to store the water for treatment before release. Federal runoff 

 pollution standards applicable to the petrochemical industry are in 

 Table 17. 



Table 17. Effluent Limitations for Stormwater Runoff 

 New Source Federal Standards in Pounds/Thousand Gallons 

 of Flow (mg/1) (Source: Reference 26) 



Average Daily Values 

 Maximum for for 30 Consecutive Days 

 Characteristic Any One Day Shall Not Exceed: 



Biochemical Oxygen 0.400 (50) 2.210 (25) 



Demand (5 day test) 



Chemical Oxygen Demand 3.10 (371) 1.60 (191) 



Solids 0.27 (32) 0.17 (20) 



Oil and Grease 0.126 (15) 0.067 (8) 



pH Within range of 6.0 - 9.0 



67 



