30 



Table 3-2 



Total Organic Carbon Values at the Portland Disposal Site Reference Areas 



Area 



Rep 



TOC 



Average TOC 



SEPvEF 



1 



1.3% 



1.3% 



2 



1.2% 



3 



1.4% 



SREF 



1 



0.80% 



0.85% 



2 



0.90% 



EREF 



1 



0.60% 



0.60% 



2 



0.60% 



3.4.2 Metals and PAHs 



Reference station samples and samples from the surface of the cap were analyzed for 

 metals and PAHs. Non-normalized metals values are presented in Table 3-3. In general, 

 cap station values are within the ranges found at the reference stations. Cap stations D7, F7, 

 and H5 do have metal values above those at the reference stations, with some exceptions. 

 Mercury is higher than the highest measured reference value (0.087 ppm at SEREF) in all 

 but three of the stations measured (D5, E3, and F3) at levels ranging from 0.089 to 

 0.72 ppm. All of these values, however, are in the "low" category defined by the New 

 England River Basins Commission (NERBC; NERBC 1980) for Maine (<0.5 ppm) except 

 for the value measured at H5 (0.72 ppm). Station F7 has the greater number of metals 

 values that are above the highest reference value (As, Cr, Cu, Pb, Hg, Ni); all of the metals 

 concentrations at this station are within the "low" NERBC category except for As (29 ppm), 

 Cr (120 ppm), and Ni (95 ppm). Arsenic and Ni, as measured at F7, are in the "high" 

 NERBC category for Maine (>22 ppm for As, >92 ppm for Ni), and in the "moderate" 

 category for Cr (112-513 ppm). Four metals results at H5 are elevated above reference 

 values (Cu, Pb, Hg, and Zn); Cu is in the "low" NERBC category, while Pb, Hg, and Zn 

 are within the "moderate" category. Other than F7 and H5, there are several measured 

 values that are slightly elevated relative to reference values including Cr at D5, Cu at D5 and 

 D7, Pb at B7, D7, F5, and H7, and Ni at D5; all of these values are within the "low" 

 NERBC categories (NERBC 1980). 



All results were then normalized to the percent silt/clay. For stations with gravel 

 (F7, EREF, and SREF), the gravel was removed before the sample was homogenized for 



Monitoring Cruise at the Portland Disposal Site, July 1992 



