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HomeMy WebLinkAbout1999-055 Addendum - CH2M Hill ADDENDUM No. 3 TO CITY OF ASHLAND CONTRACT FOR WORK LESS THAN $25,000 Addendum made this ; t day of ':~;-, '--~ ,1999 between the City of Ashland ("City") and CH2M Hill Constructors, Inc. ("Contractor"). Recitals: A. On October 2, 1998, City and Contractor entered into a "City of Ashland Contract for Work Less Than $25,000" (further referred to in this addendum as "the agreement"). The parties subsequently amended the agreement to extend the completion date and to modify Task 2 of Phase I (Addendum No. 1) and added Phase II, Site Characterization and Remedial Action (Addendum No. 2). C. The parties desire to amend the agreement to add additional site work and sampling for the site work remediation and coordination with DEQ. City and Contractor agree to amend the agreement in the following manner: 1. The work to be provided by Contractor shall include those tasks identified as Phase II (Site Characterization and Remedial Action) on attached "Exhibit A ". 2. The project budget shall be as shown on attached "Exhibit A". 3 The date for completion as specified in Paragraph 3 of the agreement is extended to October 1, 1999. 4. Except as modified above the terms of the agreement shall remain in full force and effect. CITY BRyEVIEWE~~O CONTENT: City~eYpartment Head Date: "TI i'~I~t Purchase Order # Coding (for City use only) "Exhibit A" Contract Addendum No. 3 SUMMARY OF EXPENSES FOR PHASE I REMEDIAL ACTION, AND REVISED COST ESTIMATES FOR PHASE II REMEDIAL ACTION REEDER PISTOL RANGE, CITY OF ASHLAND, OREGON Expenses invoiced for the Phase I Remedial Action: Task 1 Mobilization (lump sum) Task 2 Site work (3 days @ $2,650/day) Task 3 Sampling and Analysis (lump sum) Task 4 Standby $6,500 $7,950 $3,000 notbilled Total Costs Invoiced to Date: $17~450 Remaining Task to be Completed Under Phase I Remedial Action: Task 5 Closeout Report Preparation $4~000 Expenses Invoiced For Phase II Site Characterization: Site characterization, sampling and analysis, reporting $7~150 Cost Estimate For Phase II Remedial Action: Task 1 Mobilization Task 2 Site work (1 day excavation & 1 day restoration) $5,300 Task 3 Sampling and Analysis Task 4 Standby (assuming I day) Task 5 Interim Report Preparation & discussion Task 60DEQ Interaction and Meeting Support $1,024 $1,770 $1,840 $3,230 $ 800 Total Estimated Costs:$13~964 (See Attached Intermediate Results Report for Phase II Remedial Approach) REVISED APPROACH AND COST ESTIMATE FOR PHASE II REMEDIAL ACTION The following revised approach for the Phase II Remedial Action at the Reeder Pistol Range, Ashland, Oregon, is based on discussions between City of Ashland, CH2M HILL, and Oregon Department of Environmental Quality (ODEQ). The revised objectives for the Phase II Remedial Action are (1) to remove four pockets of lead-contaminated soil (identified as "hot areas" in the text) at the front face of the berm; (2) to remove contaminated "pockets" of potentially contaminated soil at shallow depth up to 1 foot at the backside of the berm based on visual observation; (3) to collect confirmation samples from the four removal areas at the front face of the berm; (4) to demonstrate that overall remaining lead concentrations are below the State Cleanup Level of 200 mg/kg based on statistical analysis of the sample concentrations remaining in the berm. To meet these objectives, the following approach is proposed: Four hot areas at the front face of the berm (based on previous sampling results) will be excavated to 2 feet deep and the excavated soil will be disposed of by the City as dangerous waste. The four hot areas are defined by high lead concentrations (from 950 mg/kg to 3,600 mg/kg) found during the Phase I remediation confirmation sampling and the Phase II investigation. Aligned from the Creek towards the hillside, the four hot areas have estimated lengths of 20 feet, 10 feet, 10 feet, and 15 feet respectively, for a total length of 55 feet. The estimated soil removal quantities at the face will be 55 feet (length) x 10.6 feet (width) x 2 feet (depth) / 27 x 1.7 = 73 tons. At the back of the berm, lead bullets were found scattered on and near the berm surface. The extent of soil removal will be based on visual examination of the distribution of the lead bullets. Only areas with a observable concentration of lead bullets will be excavated to 1 foot depth. It is assumed that slightly less than half the length (40 feet) of the berm up to 1 foot deep will be excavated. The estimated soil removal quantities will be 40 feet (length) x 10.6 feet (width) x 1 foot (depth)/27 x 1.7 = 27 tons. · The total estimated soil disposal tonnage from the front and backside of the benn will be 100 tons, based on the revised removal strategy. Four confirmation samples will be collected from the four excavated hot areas. The samples will be collected from the target height at the excavated bottom at each area. No samples will be collected from the backside of the berm. The soil samples will be analyzed for total lead by EPA Method 6010. The two samples with the highest lead concentrations will also be analyzed for leachable lead extracted by EPA Method 1312 (SPLP). Results from the SPLP analyses will be used to evaluate the leachability of lead from the berm, as requested by ODEQ. After the confirmation samples are collected, they will be sent by courier to the laboratory for quick (24-hour) turnaround analyses for total lead. CH2M HILL field crew will stay at Ashland for one day awaiting the lab results (Standby). Once the analyses are completed, and the lead concentrations from the confirmation sampling meet the cleanup requirement based on the statistical analysis, the site will be restored on the third day by leveling out the excavated areas with existing berm soil. Revised Cost Estimate for the Phase lI Remediation · Task 1 - Mobilization: No change in cost estimate. Lodging will be more expensive in the summer months, but the cost estimate will cover the increases. Task 2 - Daily Site Work: No change in cost estimate. Site work is estimated on a daily basis for labor and equipment rental (daily rates), therefore, the reduction in disposal quantity will save one to two hours of loading, but the cost will be the same. Task 3 - Sampling and Analysis: The revised approach requires less confirmation samples than the original approach, therefore resulting in a reduction of costs for Task 3 sampling and analysis. The cost reduction is $506, bringing the new total from $1,530 to $1,024. Task 4 - Standby: No change in cost estimate. Task 5 - Interim Report Preparation: No change in Cost estimate. New Task - Support Project Understanding Meeting with Client and ODEQ: A total of 16 hours by Senior Project Managers (Gentry and Harding) were incurred to support the City of Ashland to get ODEQ involved in negotiating alternative cleanup approach for the site. These hours were spent on interaction with ODEQ personnel, preparing Project Summary letter to ODEQ, attending Project Understanding Meeting with the City of Ashland and ODEQ at Eugene, and formulating statistical models for site cleanup evaluation. The total costs for this new task is $1,840. The statistical analysis and evaluation of lead concentrations on site with the new confirmation sampling data will be conducted as a part of the preparation of the site closeout report, at no extra cost to the original cost estimate. · The revised cost estimate for the Phase II remediation is $13,964.