MAHG_121191_Repair_Airfield_Storm_Drains_RFIs_Vol_1.pdf

Questions and Answers

MAHG 121191 Repair Airfield Storm Drains

Additional Reference material:

Related Solicitation, Drawings and Specifications.

RFI’s with Answers Volume 1:

1. On page 02 of the supplied drawings, the Summary of Quantities refers to the list of work features as "Payment Items". When proposing to the RFP does the contractor need to supply a list of these services and associated cost of each item and included said pricing with line item 0001 of the bid schedule or does item

0001 need to be adjusted to lump sum?

Answer: All bidders are directed to bid in Lump Sum.

2. Will the government provide all quantities associated with item No. 0001 and all sub features associated with performance of this contract?

Answer: Please per Drawings and Specifications.

3. If the contractor is proposing to utilize relative past experience from its employees, how does the government intend for the contractor to propose that experience and how does the evaluation process rank this experience?

Answer: By using the questionaire.

4. Are TWIC cards required for all employees and subcontractors that will be working on the site?

Answer: No.

5. We understand that the summary of quantities states precast class III and IV RCP, however there was a question whether or not precast inlets will be allowed because there is no section in the specifications that represents such precast items.

Therefore our question is will Pre Cast inlet structures be allowed?

Answer: Precast structures will not be allowed.

6. The specifications state that the contractor shall be responsible to protect in place without interruption of utilities not designated for removal, and that the contractor is to perform a sonar scan (x-ray) of the construction site and then prepare and submit an underground utilities report prior to construction. Whereas the General notes located on page 3 of the drawings states that these utilities are shown on the drawings; however those drawings have not been located. Will the Government provide more information as to the extent and locations of the utilities and/or the asbuilt drawings showing locations and depths? If there is no information on underground utilities how does the contractor Lump Sum price for protection and termination of such unforeseen utilities?

Answer: General notes on page 3 indicate that utility locations shown on the drawings are approximate and the Contractor shall field verify the exact locations. Contractor is responsible for marking all utilities not marked by

MS Utility or Base utility shop per Specification Section 00103 paragraphs 1.2 and 1.3. Cost shall be absorbed in other items.

7. Section 01500-4, paragraph 1.6 "Temporary Project Safety Fencing" says the contractor is to use 42" orange safety fencing with post on 10' centers, can the government specify where this product will be used and the estimated quantity.

Answer: This fencing will be used along the perimeter of the staging areas and the estimated quantity of fence is approximately 3,600 linear feet.

8. Section 01000-6 paragraph 7.0 states there is no Temporary construction fencing;

however section 01500-4 paragraph 1.6 States there is fencing. Can the

Government clarify if fencing is required and where said fencing will be installed?

Answer: No temporary chain link fence is required on this project.

9. Section 01561 paragraph 2.3 Plastic Mesh Fencing, this states the contractor is to use 36" orange plastic mesh fencing to provide visual warning and control, can this seems to be redundant to question #3. If this is fencing is required please provide the locations and estimated quantity.

Answer: The 42” orange safety fencing in Response No. 3 will be used.

10. Will the Government provide the construction detail or asbuilts of the existing concrete paving that requires cutting and removal noting the thickness and embeds and steel reinforcement?

Answer: As-built information is not available.

11. The drawings note there to be 4 phases of construction with each phase limited to a fixed duration; however these durations do not add up to the total contract period of performance. Will the Government please clarify and provide information for scheduling purposes, information regarding the penalty and time extension provisions if the prescribed phase duration is exceeded, and if this is calendar days of work days considering the contract is to only work on normal duty days?

Answer: The durations in the safety and phasing plan are for scheduling purposes only and the contract duration of 365 days governs for the project.

If the number of calendar days in a phase will be exceeded, the Contractor must provide at least seven (7) days written notice to the Contracting Officer and Base Operations.

12. Excavation and Demolition, If the contractor can provide positive drainage via by pass pumping, will we be allowed to demo the existing pipe concurrently as we install the new pipe and inlets?

Answer: Yes.

13. Section 02200 paragraph 1.01 sentence 4 states " No classification of excavated materials will be made. Excavation includes all materials regardless of type, character, composition, moisture, or condition thereof." with Paragraph 1.03 defining suitable and unsuitable materials, and then Paragraph 3.02 " Unclassified

Excavation" states that the contractor is to haul the suitable material to an area designated for surplus material and is to haul the unsuitable material to a designated waste of spoil area. The questions are:

A) If there is no requirement for soil classification during exaction, what determines if the material is suitable or unsuitable?

Answer: The material is suitable if it achieves density and stability and meets the requirements of Section 02200.

B) Please illustrate the designed areas for material stockpiling on the drawings for both suitable and unsuitable materials, for estimating purposes.

Answer: The staging areas are shown on G_03 through G_04. Unsuitable material shall be hauled off the job site.

C) In sub paragraph 3 of 3.02 its says that if unsuitable material is encountered in the bottom of the excavation that the contractor is to continue excavation as directed, How will the contractor be compensated for this extra excavation, material and time?

Answer: This item must be absorbed in other items, not measured for separate payment and job is lump sum.

D) Please clarify that the contractor will be allowed to reuse the excavated material?

Answer: Yes, if the material is suitable, see response to A.

E) 3.03 Selection of Borrow Material - this states that the contractor is to purchase borrow material from an approved source, is this a USACE approved source or local and state approved sources, and can the government provide the list of approved sources?

Answer: Material must come from a permitted source and meet the classification requirements. Source must be approved by the Contracting

Officer.

F) Will the government provide a Geotechnical report of the area, so the contractor may plan and account for adequate shoring, dewatering and trench safety preparations?

Answer: Yes, but the report was a pavement verification report and only three borings were taken. This report is to be used for informational purposes only.

G) Paragraph 3.07 Ground Surface Preparation and Paragraph 3.10 A Subgrade

Preparation, Proof Rolling. Since proof rolling inside of the excavations is not feasible, what is the method for testing and or government approval on subgrades?

Answer: The Contractor must submit the method to the Contracting

Officer for approval.

H) Paragraph 3.09 Backfill and Compaction, there are compaction requirements for Class I Structures and Class II pipe; however there is no specified Class II pipe. What backfill material shall be utilized for Class III and IV RCP, and at what compaction standard?

Answer: Paragraph 3.09A (3) describes pipe bedding and initial backfill

(One foot above the pipe). 3b or 3c shall be used for Class III and IV pipe.

Backfill for Class III and IV pipe shall meet the requirements of 1.03I

Granular Select Fill Material and shall be compacted to 95% ASTM

D1557 maximum density (top 6" to 100 percent ASTM D1557 maximum density for Airfield Pavement Subgrades.

14. Trench Drain, the summary of quantities state the contractor is to remove 1,070 lf of trench drain, without inclusion of new trench drain installation. On drawing number DD02 page 51 note #3 insinuates that the contractor is to install new 6" perforated pipe extending 18" long on both sides of the new drainage pipe within the drainage structures with a calculation of approximately 432 lf of perforated pipe. We have not found any supporting specifications, for the new trench drain nor the required materials/ submittals. Also in reviewing the detail named" Trench

Detail for Non-Perforated Storm drain pipe" on page 50 of the drawings, it may be misleading as the detail illustrates that the trench drain runs parallel to and on both sides of the drainage pipe.

Answer: No new trench drain is to be installed. The pipe does not run parallel to the pipe for the entire run, just at the drainage structures per DD_02. The approximate quantity of perforated pipe is 432 linear feet.

A) Does the Government need to include specifications for the materials, installation, submittals and measurement and payment for the installation of the

18" extensions for Trench Drains?

Answer: Project is lump sum but the extensions are part of the drainage structure. See Detail Sheet DD_01for materials and installation.

B) Please clarify is this contract is to include installation of new 6" perforated trench drain pipe, and if so please provide estimated quantities related to this item?

Answer: The 6” perforated pipes are stubbed out 18” on all sides of the drainage structures (see DD_02). Perforated pipes that are shown on

DD_01depict the pipes at the structure.

15. In reviewing the quantities for the Cured in Place Pipe we have discovered a discrepancy in the Governments "Summary of Quantities". The discrepancy is on the linear footage for Pay Item No. 32.0, 48" CIPP, based on our calculations from the given lengths on the drawings we determine the lengths to be as follows:

PP_06: 228 LF

PP_07: 70 LF

PP_14: 292 LF

PP_14: 107 LF

Length of 48" CIPP from drawings : 697 LF Summary of Quantities: 399 LF

Difference of: 298 LF.

Can you review the estimated quantity for the 48" CIPP and confirm if our total lengths are correct or if there is a typo on the drawings?

Answer: The total length of 48” CIPP should be 697 linear feet, see

Addendum No. 1 revised sheet IN_01.

16. On several of the drawings, the grade elevations on the profile view do not match the grade elevations listed on the corresponding grid chart. Please confirm which grade elevations are correct.

Answer: The grade elevations on the profile view above the structure are correct.The grids on Drawing Number 32, 34, 35, 36, 42 and 43 will be revised and re-issued by Addendum.

17. On several of the drawings, the invert elevations on the profile view do not match the invert elevations on the plan view. Please confirm which invert elevations are correct.

Answer: The invert elevations on the plan view are for the existing drainage structures. The invert elevations on the profile view are for the new pipe.

18. Due to this project taking place on the flight line, will NPCA certified precast inlets be allowed for this project? This would enable us to extremely expedite the project as a whole.

Answer: Precast drainage structures are not allowed.

19. What is the classification of the existing soil?

Answer: A limited pavement verification report was completed and was provided in Addendum 1, but soil borings were not taken throughout the entire project area under this project.

20. Please confirm which will be required for the manholes, a grate or drain lid cover.

Answer: Drain lid cover per Sheet DD_02 Drainage Structure Note #3.

21. What is the depth of the water table inside the project area?

Answer: Information not available

22. On drawing 50(DD_01), the trench detail indicates that the pipe bedding will encase approximately 50% of the exterior of the new piping. Is this the intent to continue this depth requirement for entire length of the new pipe or will the bedding depth drop off at a certain distance from the new outlet?

Answer: The bedding will continue at this depth requirement for the entire length of the new pipe.

23. SECTION 02520 “PORTLAND CEMENT CONCRETE PAVEMENT” states the contractor is to use slip forms and mechanical paving equipment; however given that this project does not consist of mainline runway pavement, and it is such a small quantity, would the Air Force consider traditional concrete placement methods? There is a concern that the random placement and small quantities involved will not support the use of a paving machine.

Our proposed sub-contractor recently placed pavement utilizing these identical specifications at the Stennis International Airport, and Neel-Schaffer was the

Engineer. They were allowed to place the concrete using steel forms, and an Allen

Vibratory Screed (that was not self-propelled), and handheld vibration in front of the screed.The project was successfully completed to their satisfaction, and the

Owner was able to have the work accomplished at a reasonable price.

Question: Will the government allow traditional forming/ finishing methods, with placement utilizing steel forms, and an Allen Vibratory Screed (not self-propelled), and handheld vibration in front of the screed inlue of slip forms and a paving machine?

Answer: Use of a vibratory screed and handheld vibration has resulted in issues related to uniform consolidation of concrete on some past projects. We will allow this method provided the Contractor submits a construction and testing plan to verify they will achieve proper consolidation of concrete throughout.

24. Can the existing storm lines that are called out to be removed be grout filled and abandoned in place instead and the replacement lines installed alongside?

Answer: : No, the pipes that are called out to be removed must be removed.

25. The quantities listed in the chart on the drawings do not agree with the quantities shown on the area plans. And some items appear on the area plans that are not listed in the chart (i.e. box trenches, inlets removed but not replaced, etc.). Are we to bid the quantities listed in the chart only or the quantities shown on the area plans?

Answer: : Contractor is to bid the quantities he determines from the plans and specifications.