Amendment_0004_Attachment_1_Contractor_Questions_and_Answers_FINAL_4pgs_0004.pdf

Questions from site visits for Sherman Homes Well #1 and #2

Well #1 site location

1. Confirmed that a pad area, approximately 30ft x 30 ft will need to be mowed prior to drilling to reduce fire risk during drilling operations.

2. There are two potential well site locations within lot 8, as depicted on the attached map as 1-A and 1-B. Any minor vegetation removal will be the responsibility of the park after the contract is awarded.

Well #2 site location

1. Depending on the height of the proposed drill rig, there is potential that a powerline needs to be tightened.

a. It will be the responsibility of the selected contractor to coordinate with Avista to pull line tight to ensure clearance.

2. Discussed the requirement for the new well(s) to be 50 ft from septic tank and 100 feet from leach field.

a. Location 2-A as identified on the attached map will require two Ponderosa Pine trees to be removed. If this site is selected, NPS will remove the trees post-award.

b. Alternative site 2-C was identified on lot 1 that no longer has a vacation cabin. NPS will brush the road out post-award if this site is selected.

3. There is a decommissioned pit toilet adjacent to proposed well 2-A. NPS to follow up when outhouse was decommissioned.

a. NPS may not have a record of this. Combined with an existing septic drainfield that is close to the 100’ set-back, alternative location 2-C was selected as identified on the attached map.

General Questions

1. Contractor asked if the Buy American Act applied to this contract.

a. Yes, Clause 52.225-9 – Buy American – Construction Materials (October

2022) applies to this contract.

2. Since NPS is requiring the pump to have its own power, will the well need its own meter and panel/base.

a. Yes, contractor’s responsibility to work with Avista for a pole drop down (pole is within 200 LF from all well locations) and install conduit to well location. A support structure will be installed with breaker box, main shut-off and pump controls attached to support. Each of the two wells will have a meter base.

3. Contractor asked if an in-well pressure tank is acceptable.

a. Yes, NPS preference is an in-well pressure regulating system to reduce the number of facilities above ground.

4. It was noted that the best quality of pumps are not made in America, such as:

Grundfos, Goulds and Franklin. Worst pump controller: Pentore

a. It will be the contractor’s responsibility to select a pump and, if applicable, apply for an exception to the Buy American Clause.

5. Due to the proximity to Lake Roosevelt, contractor asked if building sump, trench and/or berm would be acceptable to ensure well drilling cuttings do not enter the lake.

a. Yes, either of those three methods are acceptable to ensure drilling cuttings do not reach Lake Roosevelt.

6. How will the wells be tested for flow?

a. Add lockable spigot, sounding tube and pitiless adaptor will be added to the new well, which will allow a flow test.

7. Contractor stated that the specified ½ horsepower pump insufficient.

a. Potential contractors should be sized appropriate for depth and flow required for system to contract. Pump should be sized for the maximum 400’ depth at 5 GPM, likely a 1 HP pump.

8. Does the casing need to be grouted and to what depth is the casing required?

a. The casing does NOT need to be grouted. Casing will be required to an elevation of 1208’ to reduce lake water influence of the well.

9. Is an expansive flow test required?

a. NPS was unable to determine this. Jon Espinoza with WA Dept. of Ecology explained the only test his office required was the air test. NPS preference is contractor will perform air test.

b. NPS followed up with LTJG, US PUBLIC HEALTH SERVICE, Public Health Consultant, NPS Office of Health & Safety. We are waiting for a response but will assume an expansive flow test is required.

Request for Clarification Sherman Homes Well(s)

1. Attachment 4 Section 5.3 Well Casing Installation: Bullet 4 Seal casing to prevent surface water infiltration. This is referred to in the industry as a surface seal. The state of Washington requires a minimum depth of 18’ and a minimum of 2 inches of seal outside of the casing. For 6” casing this would result in a 10” diameter over reamed hole with approved seal material filling the annulus. This is most commonly performed using 3/8” Bentonite Chip. This is the most common method for constructing surface seals in Washington State. Depending on ground conditions, the driller may elect to deepen the surface seal to a depth greater than the 18 ft minimum depth required by code. In the next section 5.4 Grouting:

a. Bullet 1 Pressure grout the annual space from bottom to surface.

i. Pressure grouting from bottom of the surface seal to the surface is impractical because the surface is open to atmosphere thus negating the effectiveness of pressure grouting, this is not a commonly approved construction method for a surface seal.

ii. Question 1. Please confirm if you require pressure grouting of the surface seal.

1. Per Northeast Tri County Health District Well Site Evaluation Inspection: The well will likely be located within 200' of surface water. If the well is located within 200' of the OHWM, the well must be drilled, cased, and sealed to a depth greater than 50'.

b. Bullet 2 – Utilize approved bentonite or cementitious grout materials.

i. Bentonite Chip (3/8”) is the most common State approved method for creating an effective surface seal and is the method A&H recommends utilizing for construction of the subject well(s).

ii. Question 2. Please confirm that utilization of the state approved surface seal construction method of Bentonite Chip (3/8”) will be an acceptable method of surface seal construction?

1. State approved seal construction method is acceptable.

c. Bullet 3 – Prevent voids within the grout column

i. Bentonite Chip method prevents voids within the surface seal due to its swelling characteristics. When this product is wetted it can swell, increasing volume by 5 to 8 times. When using grout for a surface seal the use of a tremie pipe allows for the grout to be placed from the bottom of the surface seal to the surface, thus creating a seal with no voids.

ii. Question 3. Please confirm that utilization of the state approved surface seal construction method of Bentonite Chip (3/8”) will be an acceptable method of surface seal construction?

1. State approved seal construction method is acceptable.

2. Section 5.2.4 of Attachment 4 specifies an 8” bore unless otherwise approved. For the desired flow rate and specified motor size a well bore of 6” is appropriate. Well completion will likely have a 4” PVC liner in which the pump & motor will be placed. Drilling an 8” bore for this application does not provide any value to the completed well and will increase cost and time to execute.

a. Question 4 - The target flow rate and expected depth do not warrant the 8” bore size and a 6” bore is requested for your approval.

i. 6” bore is approved if ½ horsepower pump is deemed appropriate for up to 5,000 gallons/day. If larger pump is required and 8” bore is then required, this will remain approved. Once pump size is determined, this will be confirmed with NPS if it is determined necessary to be larger than ½ horsepower.

3. During the site visit the utilization of a slurry sump was discussed. The sump would be used to collect rock and water during drilling and that any excess or unsuitable materials would be removed at the end of construction. (Attachment 4 section 4.3 references “no waste material will be buried on site”.

a. Question 5 – Please confirm that a sump is acceptable and that removal of excess or unsuitable materials at the end of construction is also acceptable

i. A sump is acceptable and that removal of excess or unsuitable materials at the end of construction is also acceptable.

4. A previously submitted question asked if the owner has applied for and/or received authorization to construct a PWS. An initial step in this process is either approval of a design report or a waiver from a health officer or local board of health. Ammendment_0002 does not adequately address the question. Please confirm that the scope of work does not require the contractor to acquire authorization to construct the proposed water system.

Please confirm that the contractors obligation is solely the construction of a well, pump system and components described in Sol_140P8326Q0046 and subsequent amendments.

a. Please see attachment: Northeast Tri County Health District Well Site Evaluation Inspection.