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Monitoring the effects of pollution in the ocean has been done in a number of 
cases, and in this regard the monitoring of the oceans and groundwater are more 
nearly equal. 
Question. Is the potential for recovery from contamination greater in the ocean or 
the groundwater? 
Answer. There are a number of forces that diminish the import of pollution in the 
ocean. They include a large volume of water that can dilute the pollutant, and the 
opportunity for sedimentation which can remove pollution from the water column 
to the ocean floor, where it will be eventually covered. The oxidation and biological 
degradation of waste materials is common in the ocean environment. 
While any of these natural pollution abatement systems found in the ocean can 
be overwhelmed by wastes of certain quality or of sufficient volume, most of these 
natural systems do not benefit groundwater, or if they do, do so at an insignificant 
rate. While some groundwater contamination can be removed through bacteriolog- 
ical action, the usual method of groundwater treatment is to withdraw (pump) the 
groundwater to the surface for treatment. The general consensus is that, absent 
treatment after extraction, contaminated groundwater remains contaminated indefi- 
nitely. 
Question. Does contaminated groundwater pose a potentially greater human 
health and environmental risk than contamination of a similar area of coastal 
ocean? 
Answer. As far as direct human health risks are concerned, evaluating ground- 
water contamination against ocean pollution is best done by comparing two things, 
the potential paths to humans and the adequacy of preventive surveillance of those 
paths. 
In the case of groundwater, the paths are simple—direct consumption as a water 
source, or physical contact where the contaminated groundwater emerges to become 
surface waters. Both paths are very common in the United States. Unfortunately, 
surveillance of most small well systems for contamination is non-existent. 
For ocean and coastal waters the direct human health links are through body con- 
tact and ingestion through swimming or through consumption of contaminated food 
stuffs. Fortunately, city, State and Federal health agencies routinely monitor these 
pathways and cases of illness due to contaminated food stuffs or swimming in con- 
taminated ocean beaches are virtually non-existent. However, because of ocean cur- 
rents and movement of aquatic life, a direct cause and effect relationship is more 
difficult to define within the ocean environment. 
Question. Is there any waste material currently dumped which it can be stated 
unequivocally does not contain some concentration of carcinogens, teratogens, or 
mutagens? Would a prohibition on dumping of carcinogens, teratogens, and muta- 
gens prohibit issuance of a permit for ocean disposal of sewage sludge, of dredged 
materials, and/or of all currently ocean dumped materials? 
Answer. It cannot be stated unequivocally that any given material does not con- 
tain some amount of carcingoens, teratogens, or mutagens. For example, all materi- 
als contain some background levels of radionuclides, which fall into these categories. 
Therefore, an absolute prohibition on the ocean dumping of carcinogens, teratogens 
and mutagens, regardless of concentration, would probably prohibit the issuance of 
pera dumping permits for all materials, including those currently being ocean 
umped. 
Question. Has EPA published guidance documents setting forth acceptable sewage 
sludge bioassay and bioaccumulation testing procedures? 
Answer. Separate bioassay tests for different types of material have not been de- 
veloped. The bioassay procedures applicable for any material are included in two 
separate manuals. “Bioassay Procedures for the Ocean Disposal Permit Program,” 
published by EPA in 1978, contains appropriate bioassay tests for the liquid and sus- 
pended particulate phases of sewage sludge. “Ecological Evaluation of Proposed Dis- 
charge of Dredged Material into Ocean Waters,” published jointly by EPA and the 
Corps of Engineers in 1978, contains appropriate bioassay tests for the settleable 
solid phase of sewage sludge. 
Question. Have the dredged materials disposed of at the site remained relatively 
stable over the course of the disposal there? 
Answer. Dredged material, when disposed of in the ocean, is subject to the normal 
currents of the area. This results in the gradual dispersal of the dredged material 
over a wide area. Occasionally, storm events result in a faster and more extensive 
dispersal. It is this dispersal over wide areas that is depended on to prevent environ- 
mental degradation outside the site boundaries. In this sense, the Mud Dump has 
remained relatively stable over many years of disposal. 
