Question and Answers Sewer Lagoon.pdf

Question and Answers: FA4659-12-R-0013

JGAR200345 Repair Sanitary Sewer Lagoon-South Secondary

20 August 2012

1. Can we substitute 24” CMP for 24” RCP in the access road?

ANSWER: No- 24” RCP as called for in the plans.

2. Is the liner in the ponds made from strictly clay? There is no plastic or rubber type liner used?

ANSWER: Clay liner only, to our knowledge there is no plastic of rubber type liners in place.

3. Can you clarify if you want Woven Type RR Geotextile or Non-Woven Type RR Geotextile riprap fabric? The plan spec says woven but Section 858 of NDDOT calls out separation fabrics to be non-woven.

ANSWER: RR Geotextile shall be non-woven.

4. Do you have a linear feet quantity of silt fence needed? Ref Drawing 9 of 25 VA-104

ANSWER: No you will have to complete your own take-off based on what is shown in the plans to meet the swppp requirements.

5. Can we get permission to access the site to do actual measurement/quantity verification? Ref

Drawing 8 of 25 VA-103

ANSWER: Yes, to gain access to the site call the utility shop at 701-747-5200.

6. I there an actual Spec or Gradation required for the riprap, other than 4”-12”? Can there be any percentage smaller than 4” or larger than 12” allowed?

ANSWER: No spec. Other that what was included with the bidding documents, no percentage larger or smaller than called for in the specifications. The Government understands that the riprap measurements will not be perfect and minimal variations in size will be accepted.

7. Is there any testing frequency required for the riprap?

ANSWER: No, none required, unless the riprap being placed is questioned the contractor will then need to prove the product meets the specifications.

8. If it is determined that a transfer structure needs repair(other than earth work or minor joint sealing) is that to be included in our bid or will a government issued change be required?

ANSWER: Include in your proposal items required for the repair of the structure, no change order will be issued.

9. Sheet Reference Number C-302, Sheet 12 of 25; It appears that on the dashed line expanded view box, that the print is calling for another separate layer of Geotextile fabric laid over the top of the

Geotextile that extends downward towards the water. This area appears to be at the transition point of topsoil and riprap. It appears that this fabric would need to be approximately 5-6 feet wide by the entire length of all 4 pond slopes.

ANSWER: This assessment is correct. The transition fabric will be 4' wide by the length around the pond. There will be approximately 1.5' on the bottom, 1' vertical between the riprap and the topsoil and 1.5' on top.

10. If this is correct, has this Geotextile been accounted for in the estimated quantities box on sheet 8 of 25?

ANSWER: As far as the Geotextile quantity, the length of riprap repair is 5116 lf. We assumed we will use 15’ underneath the riprap and anchored and then another 4’ for tuck in and separate the topsoil from the rip rap. 19’ * 5116 = 10,800 sy. There is a minor quantity included in the estimate for underneath the access roads, and then also a minor safety factor so it came out to about 11,333 sy.

11. The Period of Performance for this project is listed as 120 days with the contractor having a Winter

Exclusion of October 15 to May 1. Please confirm the 120 days is not counted during the winter exclusionary period.

ANSWER: The 120 day period of performance does not include winter exclusion.

12. Per the SF1442 we are required to hold our pricing for 90 days which puts us potentially into a

Winter Exclusion period depending when the NTP happens. How are we to show Bona Fide Need by 31

DEC 2012 when we can't work on the site?

ANSWER: Currently this contract, if funding is received, will be awarded no later than 30 September.

Please reference section h-6 of the solicitation for information regarding bona fide need.

13. What work is required to satisfy the Bona Fide need rule by 31 DEC 2012? Are we going to have to mobilize twice? If so we need to know what equipment will be expected for us and if we are going to have to plan for storing materials on site this winter (secure from the weather) we need to know what the government's requirements and expectations are.

ANSWER: Please reference Section H, paragraph H-6 of the solicitation for information regarding bona fide need. Each company will have to decide if more than one mobilization in required.

14. The Solicitation discussed HubZone Pricing Preference "if applicable". Please confirm if FAR 52.219-

4 is applicable? Our initial thought is that it is NOT applicable with this being a Small Business Set Aside project but we would like confirmation please.

ANSWER: This clause will not be applicable, the acquisition was not set-aside for HUBZone small business concerns.

15. Is this project tax exempt from Sales Tax for materials incorporated into the project?

ANSWER: Contractors will be responsible for paying sales tax on the construction material.

16. For the proposal past performance will the government consider allowing contractors to go back to projects up to 8 years ago vs. 3 years? With the economic downturn these past several years many municipalities have not been performing this type of work and this would allow for a more thorough representation of projects prior to the downturn.

ANSWER: The 3 year relevancy for past performance will remain.

17. Can the Past Performance Questionnaires be emailed vs. faxed?

ANSWER: Either is acceptable.

18. Please confirm if the contractor will be charged for temporary water usage costs (the contractor is still responsible for the connection to the water source/hydrant.)

ANSWER: Correct the contractor will be responsible for the hookup to the hydrant. The contractor will not be charged for the water.

19. It is unclear on the drawings on if the new fence line is within the limits of the wetlands (ditch).

Please clarify. If so will a 404 permit be required for this minimal impact work (demo and replace)? Is the intent to have to place equipment matting down just to put a line fence in? If so we would think the cost of the mats would far exceed the cost of new fence.

ANSWER: The wetland delineation doesn't necessarily mean that it is wet or in cattails. The fence will be replaced at the same location it is currently located. There should be minimal disturbance to complete this work. It is the contractor's responsibility to determine the means and methods to complete.

20. The project drawings and specification indicate the requirements for the erosion controls. Will the contractor be required to submit additional drawings for approval and will approval be through Grand

Forks AFB or the State of North Dakota. Are their fees associated with these documents or is Grand

Forks AFB exempt from these fees?

ANSWER: The contractor shall follow the erosion control approval process as spelled out in Specification

Section 1000, Sub-section 13 as applicable. Currently the State and GFAFB do not charge fees for Storm

Water Permits.

21. Will the Government provide a copy of the sign in sheet on FBO?

ANSWER: Please see new attachments.

22. In order for us to full understand how the sewage flows between the lagoons and valve system we are requesting further information on the existing pipes (sizes/inverts/distance into the lagoons) so we can adequately bid on this job. The two pipes that were observed on the site visit were approximately

40 feet into the water. Is this typical of all locations?

ANSWER: As discussed at the site visit the cross-over pipes are 24" diameter, we don't have an exact elevation for each invert, and the distances into the lagoons on the average is 40 ft. A site visit to further determine for all of them would be the contractor's responsibility and can be scheduled with the

Utility shop at 701-747-5200.

23. Existing utilities are not shown on the drawings. Is this information available?

ANSWER: No additional information is available.

24. What are the existing elevations of the sewage lagoons? It was discussed that these can be gravity drained but without knowing the existing inverts of the outflow/inflow pipes it is difficult to decipher the requirement for dewatering efforts.

ANSWER: As discussed at the site visit the elevations of the lagoons are as low as they will be, the contractors should plan accordingly to install the valves using diking methods on the invert ends. The dewatering will more than likely not be an option due to the flows at the base being low, therefore not getting the dilution needed to discharge and drain.

25. One of the biggest unknown in this project is the sizing of the existing rip rap. At the site visit it was discussed that we could re-use the existing rip rap and we really shouldn't need to purchase any new.

This is contradictory to the plans and specifications. Without knowing the existing information on sizes every bidder on this project is forced into a guessing game about how much rip rap can be re-used and how much needs to be purchased new. The existing material, field stone, by design would size up in a crushing operation. A contractor could sort this out via a sieve operation but due to the irregularity of the existing stones, even with a sieve set up to meet the spec of 4 to 12" there will be stones that fit through the sieve due to their irregular shape. The specs don't indicate any tolerances on this material and the end result is a very subjective view of "uniformity" in the field by the inspector. Will the government consider adding a CLIN or sub-CLIN quantifying say 1000 tons of NEW rip-rap that can be measured with weight tickets to the field is fair to all bidders and the government will receive apples to apples bids for comparison?

ANSWER: For Govt. estimating purposes it was estimated that 30% of the existing riprap will be out of spec. on size. It is estimated that just under 200 CY of new riprap will be required to complete the work.

The contractor is responsible for his own estimate of quantities, no change orders will be completed for the riprap.

26. In lieu of disposing of any rip rap not sized per the specs would the government consider allowing the contractor to stockpile this material and allow it to remain on government property (even if it is on main base)? The material is good material and fully functional, it just doesn't meet the arbitrary size requirement. I would think the government could certainly uses this material for future projects and repairs to erosion control projects, specifically as prone as the site region is to flooding and flood events.

ANSWER: Riprap becomes the property of the contractor.

27. We were able to look into 2 valve structures. The water is obviously very murky and difficult to see.

Do all of these locations, including the locations to receive new valves (where there isn't an existing one) have pipes stubbed out to allow for a valve connection? Will any new piping need to be run? The drawings don't indicate any new piping but they don't show existing piping either.

ANSWER: A majority of the transfer structures have pipe sticking into the structure enough to allow for a valve connection. New piping may need to be run, depending on what the contractor decides when he completes his investigation as spelled out on C-301 of the drawings. We know that the one line with a valve being added here doesn't have enough to attach valve, other means or methods will need to be determined by the contractor. The method preferred would include excavating on the outside of the structure to remove approximately 4' of the C-900 then placing a 4' flange by plane in ductile and grouting it into the structure with enough to place the valve on the inside of the structure. See photos included for Structure 1, 2 & 3. The length of pipe is estimated for the structures as listed below:

Structure 1 - 3-4" of pipe inside on the curve, Structure 2 - 3" on pipe inside on the curve, Structure 3 -minimal pipe inside, Structure 4 - 2-3" of pipe inside on the curve, Structure 5 - 1' of pipe inside in the center, Structure 6 - 1' of pipe inside in the center. See as-built drawings FOR INFORMATION ONLY, no guarantees that is what is in place.

28. Spec Section 02275- RIPRAP- 2.01C : Please define "cleaned" Is the expectation to knock away loose soil and vegetative debris or will we be required to power wash these rocks with a detergent?

ANSWER: Cleaned, means free of dirt and non-rock material, sized according to the spec. The rock doesn't need to be cleaned with a detergent.

29. Spec Section 02275- RIPRAP- The specs indicate we will only have to place this material back 12" thick. Please confirm this is the intent as one stone could be all that is in place between the Geotextile and the top finished surface.

ANSWER: This is the intent for the riprap to be placed at 12" thick.

30. Spec Section 02275- RIPRAP- Is there a certain percent of stones that will be allowed to be out of tolerance? Many of the stones will be oval in shape which could pass through the sieve in one direction and be out of spec in another direction.

ANSWER: Refer to paragraph 2.01A in the specification section 02275.

31. Spec Section 02275- RIPRAP - 3.02F - This section indicates "no one are of any size can deviate by more than 4." Please clarify this statement/requirement as the allowable spec is 4" to 12" so as specified the deviation would be allowed to exist.

ANSWER: Refer to paragraph 2.01A in the specification section 02275. The reasoning for the language is so you have a smooth transition throughout the rip rap area and don't have a lot of places where you have bigger rip rap and then smaller rock.

32. Are all the existing pipes going to the structures 24" PVC?

ANSWER: Yes

33. Are there any as-built drawings (shop drawings) of the existing structures available?

ANSWER: The drawings available will be uploaded to the solicitation.

34. Spec Section 02607 Precast Concrete Pipe Structures, Manholes and Covers; 1.01A; "Modular precast barrel sections with tongue-and-grove joints, precast cover and base slabs, access hatch and frame and accessories." - Please confirm we are only replacing the tops of these structures (with the hatches, valves, PIVs)?

ANSWER: Correct you are replacing the tops, with new PIV's, hatches, etc. not the entire structure

35. The specifications indicate that top of these structures need to be manufactured. Can we cast in place in the field so long as shop drawings are provided and we can show we can meet the HS20 loading? Is the joint between the riser portion of the structure and top piece of the structure a flat joint?

ANSWER: You can cast in place if you desire with approved shop drawings, details and calculations.

36. VA-103- Fencing Detail- What is the spacing of the line posts on the fence?

ANSWER: Every 16' for spacing.

37. VA-103- There is no scale on Drawing for the Fence. The table of QTYs indicates 2970 LF but without a scale there is no way to calculate accurately. Can you please either provide a scale and/or confirm this quantity?

ANSWER: Again as stated in the Table it is our estimate the contractor is to verify. You can confirm the quantity during your next site visit which can be scheduled by contacting the Utility shop at 701-747-

5200. The estimate is based on a distance from the new fence that was installed in front of the primary cell to the trees and shrubs next to the stockpile area. It should be accurate.

38. Sheet VA-105- Vs. Profiles- Please confirm the repairs are only to happen with the INSIDE slopes of the south secondary cell. The profile sheets show repairs on both sides of the dikes. What section values should we use where this conflict occurs? Negative values on the offset of the C/L of the dike or positive values for the offset?

ANSWER: Correct the repairs will take place in the inside slopes of the south secondary cell. When looking at the increased station the left offset is negative and the right offset if positive. Due to the stationing for future project as well, the south secondary is depicted in the negative values from Sta

25+00 to Sta 35+00, and in the positive values for the rest of the pond. It is easier to tell on Sta 60+00 to

Sta 84+46.39 due to the fact there is only one side surveyed.

39. Sheet C-302- Typical Existing Section- There is no scale on this sheet but visually it appears the existing rip rap is thicker than the 1.31' average shown indicated on VA-103. For bidding purposes what are we supposed to figure? 1.31 feet thick? We would like to make sure all bidders are looking at the same project here.

ANSWER: For bidding purposes use 1.31' those numbers and quantities are in there to give you a basis for estimating, if you feel there is more to be done you will need to account for that in your lump sum bid to complete the work.

40. Sheet C-302-Typical Existing Section- Is there existing Geotextile under the rip rap? If so at what depth and should it be removed in the repair section? This was verbally discussed at the site visit but not shown on the drawings. Is it possible to show what type of material is assumed to be below this existing rip rap? We are to scarify the sub-soil don't know what we are working in.

ANSWER: There is an existing geo-textile under the existing riprap that shall be removed in the repair section. The existing geo-textile is exposed at various locations around the lagoon. The material (soil) that is located under the riprap is best identified in the soils report included in the specifications.

41. Sheet C-302- Typical Repair Section- The notes show this existing Geotextile remaining? Can you provide a detail of how the new to the existing Geotextile is proposed? Scarifying the 6" deep per the aspects and drawings will tear up the existing fabric. This existing Geotextile may also have existing damage due to the slide issues experienced on the project.

ANSWER: Correct the existing filter fabric is to remain on the bottom portion of the dike walls under the riprap with a 2 ft. portion of the existing remaining where the riprap is being removed. This portion is where the overlap with the existing and new Geotextile will take place. Simply envision the existing underneath the proposed Geotextile with stapes holding in place adequately until the riprap is placed.

The existing is not to remain in place for a majority of the area that the scarifying is to take place. The 2

ft. portion to remain could be folded up out of the way while the scarifying and recompacting is taking place.

42. Sheet C-302- Please provide a legend for the hatch patterns used, specifically when representing the soils. The specs discuss a clay liner, new clay, sub-soil material, bedding, and pond dike embankment materials yet the drawings do not represent what is where existing and exactly what we should use in the repairs. At the site visit it was discussed about re-using existing materials but unless the existing is clarified by type of soil it is difficult to decipher.

ANSWER: In looking at the Detail shown on Sheet C-302 the diagonal liner area on top represents the topsoil to be removed and replaced around the lagoon, while the criss-cross hatched area represents the dike embankment that is to be removed to place the toewall of fabric along with the minor grading that will need to take place for the tie-ins and to obtain the 4:1 slopes around the lagoon cell. All material placed underneath the topsoil and rip rap shall be Type S6 from Section 2.04 in spec 02205.

Any clay liner removed shall be replaced with Type S5.

43. Sheet C-302- Geotextile overhang above grade- Will the contractor be required to mobilize back on site to cut this material out at a later date? This certainly won't be perfectly straight and clean as shown on the drawings as you are trying to cut along a transition of soil and 4 to 12" irregular shaped stones.

ANSWER: No the contractor will not be required to mobilize back on site to cut the 1 ft. of Geotextile off above grade between the riprap and the topsoil.

44. The drawings indicate there are settling/erosion issues around the top of the structures. Was this due to a storm event? Are the structures damaged/leaking? How should we price this repair work?

How far down are we supposed to dig? What are we to backfill with? Please clarify this scope so all bidders can apply the same effort/scope.

ANSWER: We do not know what caused this; don’t believe that it was a storm event. We don't see the material that has disappeared inside the structure; investigation by the contractor will be the only way to figure it out. The Government assumes that the contractor could end up digging to the bottom of the structure. The contractor should be able to backfill with the material that is removed from the dike, as long as you are able to obtain compaction with the material that you excavate.

45. Spec Section 01000-9; Section 7.3.4- Fencing- With this area secured from the public by design, other than what is required by OSHA/EM 385, are we actually required to build a chain link fence within the secured area to keep the public out? This seems like overkill.

ANSWER: No you will not be required to construct a chain link fence around the construction site.

46. Spec Section 02211; 3.05 G discusses a government furnished disposal site. Where is this site located?

ANSWER: This can be embankment material removed from the project free of debris and garbage. It can be spread in the stockpile area after the project is complete, not in the wetlands. The area must maintain adequate drainage if this option is chosen, along with being restored by seeding and mulching.

47. Can the government please delineate on the drawings where the topsoil, clay liner material are existing and proposed? The specs discuss (in detail) what they want but the drawings do not do a fair job of telling you what is where (both existing and proposed). Same goes for the aggregate materials

(A1, A2, and A3).

ANSWER: The Government assumes the contractor is referencing the items in Spec. 2211-2 under Part 2.

The items are shown in the plans in the Details on C-301 numbers 2 and 3 along with C-302 typical repair section and the blow up of the repair section. The existing clay liner is underneath the rip rap and should not need to be removed during this project. The topsoil area changes and there will be spots where there is a subsidence and then areas where it will already be at a 4:1 down to the rip rap. We went with a conservative estimate and figured full 6" excavation of the topsoil around the pond, but that may not be necessary in all circumstances.

48. Section 02223 Backfilling- Existing Clay Liner (3.01 E and F)- It appears, in the drawings, that some of the clay liner will be removed in the grading operations to the design slopes (per profile). If this is the case is the intent to then pull out (over excavate) the clay liner to get the full depth of 12". There isn't enough design data on the drawings to determine the limits and quantify appropriately. Would the government consider a sub-CLIN on CY basis for these undercuts and other undercuts by material type to ensure competitive pricing from all bidders? It would also build a fair contingency in for all bidders on the undercuts when you specify what material goes where. Section 3.01B discusses undercuts with

Type A1 fill. Does that supersede 3.01F?

ANSWER: There will be no need to over-excavate. When removing the rip rap, there should be a sufficient thickness of clay underneath so that some fill may be used in order to match the rip rap section with a 12" rip rap section but not compromise the integrity of the existing clay liner. When grading the slope, in order to achieve a 4:1 slope, you should not have excavate lower than the topsoil in a lot of areas and since these areas are above the rip rap, just replacing the amount of clay that was removed will work for this project. Section 3.01 paragraph B of the specifications should not be used on the dike repairs portion of the project so Section 3.01 paragraph F of the specifications will apply.

49. One of our fence suppliers is questioning Spec 2.02 Barbed Wire Fence. He believes that the 9 gauge wire with 2 point barbs is a mistake. He also stated he has seen this on a few occasions from AE2S. They also stated that 12 ½ gauge with 4-pt. barbs is pretty standard for lagoon fencing but they have seen 12

½ gauge with 2-pt barbs on occasion. Can you please verify what is actually intended?

ANSWER: We will go with the 12.5 gauge with 2-pt barbs as that is what is in place currently on the updated fence. Please see attached revised specification section 2.02 paragraph A.