Agmt16 Cascade Drilling, L.P. - Laserfiche WebLink

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• Contractor will: o Visually inspect the site to locate manholes, valve boxes, etc. in addition to the utility company's mark-out and existing site utility information; o Perform electromagnetic trace of identified utilities; o Surface scan proposed injection locations to locate active and abandoned electrical lines and conduits; o Magnetic scan to identify buried metallic objects; o Hand auger to a depth of 5 feet below ground surface to expose possible unknown utilities; o Mark unknown utility locations for future full-scale remediation project; and o Identify any overhead utilities. Task 5 — Pilot Test Activities Contractor shall conduct all pilot test injections using pneumatic enhanced injection technology. During each injection, Contractor shall collect the following data points: o Zero Valent Iron (ZVI)/Emulsified Vegetable Oil (EVO) hydraulic injection pressure and flow rate; o Nitrogen gas injection pressure and flow rate; o Pressure influence at nearby monitoring points; o Quantities of ZVI, EVO and mix water injected during each event. A. PRB Emplacement Area • Contractor will inject 2,000 pounds of Ferox Flow ZVI powder via four (4) injection boreholes spaced in two rows of 2 each, 8 feet from one another • Injections will be performed using pneumatic enhanced injection methodology at three of the boreholes and direct-push injection methodology at one borehole. • Contractor will calculate and field verify the targeted radius of influence. • Contractor will abandon all borings after injection operations are completed by grouting via a tremie pipe to the ground surface using a cement/bentonite slurry. B. "D" Wells Area • Contractor will drill three injection boreholes using direct-push technology to a depth of approximately 20 feet below ground surface. • Contractor will inject 150 pounds of Ferox Flow ZVI powder and 75 gallons of EVO into three boreholes, between depths of 7 and 20 feet below ground surface, arranged in an equilateral formation around monitoring well D-6 and spaced 10 feet apart. • Injections will be performed using direct push injection methodology. • Contractor will calculate and field verify the targeted radius of influence. • Contractor will abandon all borings after injection operations are completed by grouting via a tremie pipe to the ground surface using a cement/bentonite slurry. • Upon City's request, Contractor will remove and replace up to 3 concrete parking stops in order to create a detour for vehicles. If existing concrete REV: 10-07-16 J5 Page 10 of 13 ATTY/AGR.2016.294/Cascade Drilling - Groundwater Remediation Pilot