the unconsolidated pediment In the basin indicating fine material and a low 

 energy environment. The December survey Indicated that the proposed disposal 

 site is a depression outlined by ^he 60 fnetew contour level just south of the 

 chart center. 



A smaller area was covered In the May survey since the rugged topography 

 of t!-e area would certainly prohiljilt detection of small amounts of spoil depos- 

 ited at significant distances from the disposal point;. The proposed disposal 

 site was again evident as a besin In the qente** of the bathymetric chart. The 

 faas'^n can be seen in prof1"!e on lanes 11 through 14 of the May survey (Fig. B-3 

 (c + d]). 



Currents 



Long te-m current measurements were obtaine*;! at 4^o 34'N, 70° 02 'W in the 

 cente*" of the proposed disposal area, The meter was installed on a taut wire 

 moorirg 1,5 meters above the bottoi" and reco^'ded at 2 minute Intervals from 

 5 August to 26 September 1978. The speed and 4"'^ect1on versus time, probability 

 densi'iy c'-ist^-i bution and motion ellipses for these data are presented in Figure 

 B-5 ^■'-d}. Note that the probability density distribution and motion ellipses 

 are cvt-j"' ati v^ sc that the dlstrlb^tlpn and ellipse on the final figure (B-5d) 

 represents the entire dat^ record, 



"■■■e data for the "ortland current meter recprd are summarized in Table B-1 . 

 TVipv-o are sever?.] s ■' on *f leant features shown by these data that reflect on the 

 uti I'ltaf'on cf the Portland disposal site as a containment site for dredge spoil 

 dispor-e"". Mcst •'mpo-tant of these Is the horizontal kinetic energy, which at 

 PorV?.rd, has t'^e lowest value nieasure?? in all the New England disposal sites. 



