2009-323A - Laserfiche WebLink

Home Browse Search

decanting process. If at any time during this process effluent turbidity violates water quality standards, the effluent must be retained until analysis of the interior surface waters shows the suspended solids concentration to be within acceptable limits. Decanting then continues in this manner until all ponded water is released over the weir. Subsequent dewatering techniques are discussed in Chapter 4 . 0 . 3.4 Effluent Monitoring As discussed in the preceding section, effluent monitoring will be an integral part of facility operation . The IR- 14 containment basin has been designed to produce effluent which meets water quality standards for Class III waters asset forth in Chapter 62-302 ofthe Florida Administrative Code. These rules require a comprehensive monitoring program to document permit compliance. The monitoring program should therefore continue throughout active dredging and decanting operations . Effluent samples should be taken and analyzed as often as practical . The minimum recommended sampling frequency is two times per eight hour shift. Although effluent turbidity is only 1 of 29 parameters addressed in Florida ' s state water quality standards, compliance with these standards has been historically based on turbidity alone for several reasons. First, turbidity is reliably measured in the field and is the only water quality parameter over which the site operator may exercise direct control . Second, turbidity is a strong indicator of general effluent quality since many contaminants, most notably metals, exhibit a strong affinity for fine particles . Thus, reducing turbidity should result in an overall improvement in effluent quality. However, the disturbance of contaminated sediments may result in the release of other pollutants (predominantly nutrients and hydrocarbons) which do not necessarily associate with fine particles. If the in situ sediments contain elevated levels of these contaminants, turbidity may be an inadequate indicator of effluent quality. Shoal sediments should undergo comprehensive elutriate and dry analysis to determine the presence ofthese contaminants . Additional testing under the effluent monitoring program , ifrequired , should then focus on those contaminants documented by pre-dredging sediment analysis. Because effluent turbidity is a primary water quality parameter for site operation, compliance with turbidity standards will largely control both the dredge plant output and the release of effluent. However, the 33