carbon, and oil and grease. The rest of the mounds again showed 

 only a few parameters with levels elevated from reference (Table 

 3-22) . 



The % total organic carbon, % total nitrogen, and % total 

 hydrogen data were not tested statistically because these 

 parameters generally follow the % total carbon data. Unlike these 

 other parameters, the % total carbon data showed the best 

 replication and was consistently above the detection limits, 

 therefore providing better information. The % total carbon levels 

 in the Botttom core section samples were consistently elevated 

 above reference levels for all the mounds except CS-2 and STNH-N, 

 where levels were either not significantly different or were 

 significantly less than reference (Table 3-22) . 



PCB concentrations could not be tested statistically 

 because only single composite samples were analyzed at each 

 station. However, as already indicated, none of the mounds 

 exceeded the NERBC 'Moderate' upper limit for PCB's of 1.0 ppm. 

 The highest PCB concentrations were detected at the FVP, MQR, CLIS- 

 86, NH74, and Norwalk mounds, where average concentrations ranged 

 from 0.33 to 0.86 ppm. This compared to the 0.06 ppm PCB's 

 detected at the reference station (Tables 3-1 through 3-19) . The 

 rest of the mounds ranged from 0.04 to 0.15 ppm PCB's, essentially 

 within the range detected at the reference station, and well below 

 the 0.5 ppm upper limit for NERBC 'Low'. 



Concentrations of most parameters at the eight stations 

 sampled around the STNH-N disposal mound were not statistically 

 different from the concentrations at station Center (Table 3-23) . 

 Stations 100S and 100N did show significantly lower concentrations 

 compared to Center for most of the trace metals in the Top 2 cm 

 samples. COD levels were consistently higher than at the Center 

 station for both Top and Bottom samples from 400W, 150W, 200E, 

 400E, and 200N. Levels of Cr and Cu were consistently higher at 

 these same stations in Bottom samples, and Pb was elevated in both 

 Top and Bottom samples from 150W and 200E (Table 3-23) . However, 

 the magnitudes of the differences between the Center station and 

 the outlying mound stations were not large. More importantly, 

 there did not appear to be any consistent trends in chemical 

 concentrations with distance from the STNH-N Center station. 



Statistical comparisons between the concentrations 

 measured in the Top and Bottom core sections from the STNH-N 

 stations also showed few significant differences (Table 3-24) . At 

 a few of the stations, the levels of one or two parameters were 

 higher in the bottom sections, particularly at station 200E for Pb, 

 Zn, Cu, and oil and grease. Cu at station 100S, and Pb, As, and 

 Fe at the Center station had significantly lower levels in the 

 Bottom core section samples. 



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