244 



The disi)os<al site was some 12.000 feet long by 6,000 feet wide with an average 

 dei>th of 60 feet. The continuous movement of ocean waters in this area pro- 

 vided a complete water exchange every five hours or almost five times per day, 

 resulting in a tremendous dilution factor. This dilution was equivalent to one 

 gallon of organic material in every 1.5 million gallons of sea water. 



It took approximately six hours for our sludge solids to be dispersed, stabilized 

 and settled to the bottom of the area. At the end of this perio<l the normally 

 prevailing saturated dissolved oxygen conditions were reestablished throughout 

 the site. 



It should now be noted Camden, N. J., also used this same site for sewage sludge 

 disposal. 



We can demonstrate that in the twelve years both Philadelphia and Camden 

 had used this site on the continental shelf no discernable deterioration of the 

 area or aquatic life had occurred. The point here is that the ocean's assumulative 

 capacity and dilution factors for wastes of this type cannot and should not be 

 discoimted. 



At the very inception of the sludge disposal project. Philadelphia was con- 

 cerned about any possible deleterious effects of its actions on the ocean environ- 

 ment. And this was certainly well in advance of any national or world attitude 

 on the subject or federal obligation to do so. Philadelphia surveyed and in con.sul- 

 tation with others deliberately selected an economically unproductive shell fish 

 area for the disposal site. Records were kept and surveillance maintained over 

 disposal operations. The city by its own initiative and entire expen.se, engaged 

 the Franklin Institute Research Laboratories to make an investigation of the 

 ecological conditions at the disposal site. This independent study undertaken by 

 the Franklin Institute Research Laboratories included the efforts of the Tliomas 

 Jefferson Medical College and the marine science consortium indicates that there 

 was no degradation of the ocean environment within and around our former 

 disposal location. 



The conclusions of the Franklin Institute study were : 



1. The heavy metal concentrations within a six nautical mile radius of our 

 disposal area are the same as those up to 12 nautical miles outside of the disposal 

 area. 



2. Metal concentrations in clam meats inside the disposal area are the same as 

 clams outside the disposal area. 



3. The coliform counts within the disposal area, when found at all, were 

 well within U.S. public health service standards for drinking water. 



4. The marine life within the disposal area is numerous, diversified in species 

 and healthy. 



Despite the findings of the Franklin Institute repor't which .showed the Phila- 

 delphia practice to be harmless for 12 year background levels and therefore 

 environmentally acceptable and sound, EPA told Philadelphia to abandon the 

 site and issued the city an interim permit to continue our sludge disposal 

 activities at a new site some 50 miles southeast of Cape Henlopen. Delaware. 



The new site poses some problems if conditions imposed by the Ocean Dumping 

 bill are to be evaluated properly. The water is twice as deep, there is no back- 

 ground information, and the area w-as being used for the dumping of wastes 

 from a chemical plant. There is a temperature gradient and therefore at certain 

 times of the year, the thermocline may materially affect disposal and testing 

 conditions. 



EPA has made a hurried study of the vicinity prior to our initiation of using 

 the site. Philadelphia is cooi>erating in the overall monitoring and evaluation 

 work by providing surveillance, all types of bio-chemical testing and record keep- 

 ing for EPA. This kind of involvement is advocated and should be fostered to a 

 greater extent by the Government. Had EPA been involved in the work of the 

 Franklin Institute, at our former disposal site, perhaps that study would have 

 received wider acceptance. As it now stands our disposal costs have increased 

 by 50% by virtue of transportation to the new site and the environmental ac- 

 ceptance of our disposal practice at this new location remains to be seen. 



It has l)een suggested to dispo.se of digested sewage sludge off the Continental 

 Shelf. This alternative would appear less desirable at this time due to the lack 

 of information and time to make a proper assessment. The water off the Con- 

 tinental Shelf is a minimum of % mile deep, extremely cold with limited light 

 penetration, and as such, biological and aquatic activity is arrested to a minimum. 

 Sewage sludge material in this case will not be readily assimilated into the 

 ocean environment and recycled. The recycling of our natural resources is of 



