SECTION 3 
RECOMMENDATIONS 
EVALUATION OF BIOTOXICITY 
Possible links between the dieoff of associated organisms and 
previous oysterkills should be further investigated. In addition 
to monitoring fouling communities of oysters, transite sheets 
should be placed on or near oyster bars and be sampled periodi¬ 
cally. These sheets make quantification of the fouling organisms 
simpler and quicker when the effects are not gross. 
The slower oyster growth in Chester River may be related to 
the oysterkill causal factor(s). Year-round sampling of oyster 
bars in the Chester River to monitor new growth is recommended. 
An area with a similar salinity regime and without such oyster- 
kill phenomenon should be sampled simultaneously as a control. 
The studies recommended above could be performed concurrently. 
A study continuously monitoring dissolved oxygen during 
periods when oysterkill may occur is recommended. 
PHTHALATE ESTERS AND RELATED CHEMICALS 
The levels of alkyl phthalates observed in the Chester River 
do not appear to present an immediate threat. However, the oyster 
lives a perilous existence. It is quite possible, and perhaps 
likely, that the alkyl phthalate levels are changing rapidly 
enough in the Chester River and the greater Chesapeake Bay to 
constitute a serious threat at some future time. 
It is recommended that the rate of buildup be monitored 
through piston cores taken in well-stratified sediments. The 
goal should be to forecast the date when the extrapolated levels 
will be reached where healthy oyster production will be prevented 
by the presence of these ubiquitous chemicals. 
It is recommended that the Morgan Creek sediments be surveyed 
for evidence of alkyl phthalate accumulation. The creek serves 
as a conduit between the Tenneco pond and contiguous farmland 
using the discharged water for irrigation purposes. The Tenneco 
Pond sediments are likely to be weakening in their role as a sink 
for these chemicals. Eventually, their sorptive capacity is 
8 
