Q&A #1.pdf

Solicitation Update: Detroit Marinas Excavation and Resiliency Project Reference: SolicitationID|1620| on behalf of kulm@co.marion.or.us

(1) Addendum #1 (attached)

(2) ITB updated with Addendum #1 edits (attached)

(3) Pre-bid Conference sign in sheet (attached)

(4) Questions and Answers were posted for this opportunity.

Question: Why do some compaction requirements refer to a percentage of maximum dry density and others refer to proof rolling?

Answer:The requirements referring to a percentage of maximum dry density apply to imported materials only (Drawing notes 17 and 18 on Sheet C1.0 and Specification 31 20 00 Earth Moving Part 3.4). Given the heterogenous nature of material to be excavated from the marinas, a performance-based compaction

OregonBuys Bid # C25102-00012392

See CS1620-24 OregonBuys Posting Page for instructions on how to access bid documents.

standard was established for this excavated material (Drawing note 19 on Sheet C1.0)

Question: Can excavation be performed during the summer months when the reservoir is high?

Answer:No, excavation in the summer would require closure of the marinas during their operating season and is not allowed.

Question: What permits, if any, is the contractor going to be required to obtain per Section 01 57 19 1.4.

Answer:Additional permit requirements are described in Section 02 00 00 Mobilization and Site Preparation.

Question: Is there a list of compiled changes to the bid documents from the first bid documents to the re-bid?

Answer:No

Question: Is turbidity curtain going to be required? Given the nature of the existing material, turbid water from the excavation area will be able to freely flow through the bar run even with aggressive dewatering systems. There are no mentions or requirements for turbidity curtain unless they are in the Nationwide #27 permit that is not provided.

Answer:As turbidity curtain is not shown on the drawings or required by the specifications, turbidity curtain is not required.

Question: Section 31 23 19 mentions the Nationwide #27 Permit, is this permit available for the contractors?

Answer:Nationwide Permit #27 General and Regional conditions are available online. USACE Permitting for the project is underway and a final permit is not available. The bid documents provide expected permit conditions.

Question: Are there historical annual records available in regard to the water levels and when then rise to the bottom elevations of the new excavation areas?

Answer:Water levels for the reservoir are available from the USGS gauge https://waterdata.usgs.gov/nwis/uv?site_no=14180500&legacy=1

Question: Sheet C1.0 Site Grading Note 17 states "If fills are needed for structural support, they shall be installed in no more than 8-inch lifts, and shall be compacted to at least 95% of the maximum dry density for fine grained native soils unless otherwise specified on the plan. The top lift of fill shall be compacted to 92%. All other soils shall be compacted to no less than 85%." Given that the excavated materials will be a bar run material and untestable, will this compaction requirement need to be adhered to for the peninsula fill? Once the top 2' of material is removed and mixed with other excavated material to create the core of the peninsula and then bridged with the remaining excavated material, any settlement should occur from placing that material. Also given the fact that the material is bar run, proof rolling might not even be feasible.

Answer:The requirements referring to a percentage of maximum dry density apply to imported materials only (Drawing notes 17 and 18 on Sheet C1.0 and Specification 31 20 00 Earth Moving Part 3.4). Given the heterogenous nature of material to be excavated from the marinas, a performance-based compaction standard was established for this excavated material (Drawing note 19 on Sheet C1.0)

Question: Sediment/Soil Dewatering Agent - Can you provide a list of agency approved dewatering agents that the contractor can utilize, if required, given the environmental constraints of the project?

Answer:The county has not developed a specific list of agency-approved dewatering agents

Question: Can the tolerence in the excavation area be defined ie +/- 1' from the design lines and grades?

Answer:The following text has been added as a new Part 3.1.C of Specification 31 20 00 Earth Moving: “C. Excavation Tolerance: Without specific Engineer approval, elevation tolerance for the excavation leave surface shall be + 6-inches and minus zero inches. In areas of excavation sideslopes, the excavation tolerance shall not allow a slope steeper than what is prescribed by the Contract Drawings.”

Question:

31 20 00 Specification States - Silty material shall be thoroughly amended with CONTRACTOR-proposed dewatering agent prior to placement. Plan sheet C6.1, Detail F states "Potentially Amended with Fly Ash."

There are many options that could be proposed.

Please clarify what options (if any) that will not be accepted for the dewatering agent.

Answer:Amendments that would significantly change the pH of the silty material (i.e. lime, Portland Cement) will not be allowed. Amendments must not be a hazardous waste or solid waste as defined by the Oregon Department of Environmental Quality. If imported soil is proposed as an amendment, it may require sampling to determine compliance with the Sediment Evaluation Framework for the Pacific Northwest SL1 benthic toxicity screening levels (Table 6-2).

https://usace.contentdm.oclc.org/utils/getfile/collection/p16021coll11/id/2548.

Question:

The Bid Schedule Shows the Incorrect ITB number on pg. 27

All of the sections required on page 9-10 under c.4.4 are incorrect on the new

ITB.

For example:

CCB Registration requirements shows it under Section F but on the ITB it shows it under Section G. It is the same for all the following requirements.

Can these be corrected?

What is the requirements for liquidated damages? Bullet point #4 shows [$XXX.XX Insert Applicable Amount]

Answer:Addendum #1 which will be posted today will address these changes.

Liquidated Damages to be determined upon contract negotiations.

Question: Will monitoring of vibration, noise, slope stability, water levels and more be required?

Answer:None of the monitoring described is prescribed by the contract documents.

Thank you!

Krista Ulm kulm@co.marion.or.us

CS1620-24 ITB ARPA-Detroit Marinas - rev.pdf (1/9/2025 4:50:47 PM - Public: True) CS1620-24 Addendum 1 1.9.25.pdf (1/9/2025 4:41:59 PM - Public: True) 31 20 00 EARTH MOVING.pdf (1/9/2025 3:51:53 PM - Public: True) CS1620-24 Sign in Sheet 1.7.25.pdf (1/8/2025 11:02:01 AM - Public: True)

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