Exhibit A
Nashua - Crown Street Park & Ride Project
Scope of Work and Task Descriptions
June 15, 2016
d. Fill the casing with water to a depth of 24 inches and allow to pre-soak for 24 hours;
e. After pre-soaking, refill the casing with 24 inches of water and record the drop in
water level from the top of the casing at the end of one hour;
f. Divide the drop in water elevation by one hour to obtain the infiltration rate for the
given observation;
g. Repeat e. and f., above, at least three additional times, for a minimum of four
observations in each location; and
h. Use the lower of the average of the calculated infiltration rates or the last
observation.
Laboratory Testing - GZA will conduct a geotechnical laboratory testing program including soil
gradation analyses on up to four granular soil samples recovered during subsurface explorations.
These tests will be used to confirm the field classifications of our field engineer and to estimate the
engineering properties of the soils. Testing will be performed at Thielsch Engineering's Cranston,
Rhode Island soils laboratory.
Based on apparent staining, odors, and/or PID measurements, GZA will submit up to four soil
samples and one duplicate sample to ESS Laboratories (ESS) in Cranston, Rhode Island for
analysis including: VOCs by EPA Method 8260B, polycyclic aromatic hydrocarbons (PAH) by EPA
Method 8270D, total petroleum hydrocarbon (TPH) by EPA Method 8100, and the Resource
Conservation and Recovery Act (RCRA) 8 metals by EPA Method 6010B. Soil analytical results will
be compared to the soil remediation standards (SRS} included in Env-Or 600 - Contaminated Site
Management (Env-Or 600).
Up to five groundwater samples and one duplicate sample will be submitted to ESS and analyzed
for VOCs by EPA Method 8260B, PAHs by EPA Method 8270C, and the RCRA 8 metals by EPA
Method 200.7/200.8/245.1. Groundwater data results will be compared against New Hampshire
Ambient Groundwater Quality Standards included in Env-Or 600.
Engineering Analysis and Report Preparation - GZA will conduct engineering evaluations and
develop geotechnical recommendations for design and construction of the Park and Ride. GZA
will provide a geotechnical engineering report presenting the results of the subsurface
investigations, laboratory testing, engineering evaluations, and geotechnical recommendations for
design and construction. The report will include the following, where applicable:
° Summary of subsurface explorations and laboratory testing;
° Summary and interpretation of subsurface conditions;
° Summary of infiltration rates and observed depth to seasonal high groundwater table;
° Pavement design recommendations;
° Results of test pits for seasonal high groundwater and infiltration testing;
° Results of soil and groundwater sampling and environmental laboratory testing;
. Suitability of on-site soils for reuse during construction; and
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