The near surface fill and organic soils will tend to 

 compress and settle with time. Therefore, it is 

 recommended that pavements and final surface treatments be 

 designed to accommodate future ground movements. 

 Settlement estimates can be provided as more data becomes 

 available. 



B. Site Excavation and Filling . As currently proposed, 



extensive excavation for the proposed below grade garage 

 is envisioned. Excavated soils will be comprised 

 primarily of the miscellaneous fill, organic soil, marine 

 sand and varying amounts of glacial till depending on the 

 number of below grade levels. Buried structures including 

 the existing warehouse foundations (oak piles and 

 reinforced concrete pile caps) , portions of the existing 

 granite block seawall, and boulders in the glacial till 

 soils will also be encountered during excavation. 

 Shifting the location of the proposed south perimeter 

 garage wall may significantly reduce excavation of 

 sections of granite seawalls. 



The majority of excavated materials are not considered 

 suitable for use as on-site fill except as common fill 

 under landscaped areas or other non-structural 

 applications. Therefore, for current planning it should 

 be assumed that excavated material will be disposed of 

 off-site. However, reuse of excavated granite blocks for 

 reconstruction of shore protection may be advantageous. 

 Refer to our report on "Oil and Hazardous Materials Site 

 Evaluation" for specific comments pertaining to off-site 

 disposal of excavated soils. 



As indicated in the previous section, the subsurface fill 

 and organic soils will consolidate and settle if the soils 

 are subjected to additional surface loads. Therefore, to 

 the extent possible (considering flooding associated with 

 storm tides) , existing site grades should be maintained. 

 If site filling greater than 1 to 2 ft. is proposed, 

 further evaluation of anticipated movements will be 

 required. In addition, recommendations relative to design 

 of pavements and utility support, as well as building 

 foundations and seawalls in these areas will require 

 evaluation in greater detail. 



C. Seawalls and Shore Protection . Preliminary visual 



inspection of the existing granite block seawall indicates 

 that the wall is in relatively good condition except the 

 area just west of the pier and near boring B102. Previous 

 experience in the Boston Harbor area with similar seawalls 

 indicates that these walls have a marginal factor of 



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