CLARIFICATIONS

  1. Detail 1 on sheet M-501 has been included to provide general guidance only for pipe installation. However, as the underground portion of the pipe will be installed via hand digging, we do not anticipate the use of bedding material, nor will compaction testing be required. The Contractor shall take care in compacting and restoring to match existing, with the County’s and Engineer’s approval of restoration being required upon completion.
  1. Only underground piping is to be contained. 6-inch containment pipe shall begin at 1-inch above the point of entry into the ground and extend to 1-inch above grade at the exit point. At the pipe trench area (near degasifier units), containment pipe shall extend through the trench wall to the interior and terminate.
  1. The route displayed for pipe installation in each location is a proposed route. The Contractor may adjust the route at his option and at no additional cost to the County. Route modifications to be reviewed and approved by the County and Engineer.
  1. Unistrut spacing for wall supports shall not exceed 6 feet.
  1. Directional arrows shall only be placed on the above-grade portions of the piping (every 10 feet). Directional arrows are not required for below-grade piping.
  1. Contractor may utilize a combination of hand digging and mini excavating equipment at Contractor’s option. Please note however, that sufficient hand digging should be performed in advance to verify existing utilities, and the Contractor will be responsible to perform any repairs for damages caused by equipment, at no additional cost to the County.
  1. Restoration within the disturbed areas may be performed with Bahia seeding.
  1. Detail 4 on sheet M-501 has been modified (see attached) and Detail 4a has been added. In general, the changes include the transition from 2-1/2-inch CPVC to 1-inch 316 SST (thr), with 316 SST fittings and valves and a 316 SST diffuser assembly. For bidding purposes, the depth of cover for each valve is estimated to be 4-feet deep. Therefore, a 4-deep prefabricated valve vault is specified for installation above the pipe where the injection point will be located. Prior to ordering the valve vault, Contractor shall expose area, confirm cover and adjust box size/orientation as necessary.
  1. The proposed 2-1/2-inch chlorine carrier pipe shall be CPVC, not PVC.
  1. The connection to existing the 2-1/2-inch chlorine piping at the recarbonation basin shall include the addition of (2) 2-1/2-inch ball valves, (1) for the new line to the new tie-in point and (1) for the existing line to the existing rebarbonation basin. The plans currently show a single valve on the new line.
  2. Two (2) Hach CL17 Analyzers shall be purchased and installed. The analyzersshall be mounted on top of the Blending Tank as shown in Figure 1 (attached). One analyzer shall be used to test the free chlorine residual within the 42-inch line from the reverse osmosis process (prior to the tee connection with the 30-inch line from the lime softening process) and the second analyzer shall be used to test the free chlorine residual within the 30-inch line from the lime softening process. Mounting shall match that of the analyzers located on top of the blending tank (see photo 1, below). Plumbing configuration shall match that of the Hach CL 17 located adjacent to the Recarbonation basin (see photo 2).Two (2) sample pumps shall be provided to withdraw water from the 42-inch and 30-inch lines for sampling. The sample pumps shall be mounted on top of the blending tank and shall be self priming pumps (Dayton model 6GPG4, 1/3 Hp, single phase 115V or approved equal). Tapping saddles shall be used to connect the sample lines. Prior to installation, separate authorization shall be required for this installation. At this time, it is not known whether the installation will be required. Following completion of the chlorine feed line installation, the Engineer will submit documentation to the Florida Department of Environmental Protection (FDEP) which will confirm whether the units are required to be installed or not. If the units are not to be installed, the Contractor will deliver both Hach CL 17 units to the County for future installation. Contractor will be reimbursed for the purchase and the remainder of the work will be removed from the Contract. To assist with this item, the bid form has been revised to include the following:

1.a.Supply (2) Hach CL 17 AnalyzersLS

1.b.Install (2) Hach CL 17 AnalyzersLS

1.c.Electrical/Instrumentation Allowance for AnalyzersLS

The installation (item 1.b.) shall include the tapping saddles; 1-inch sample piping buried and affixed to the wall of the blending tank with unistrut supports; mounting of the Hach CL 17 units with sunshields; furnish and installation of the sample pumps (less electrical); installation and connection of the plumbing for the Hach CL 17 units (to match that shown in photo 2) and related items necessary to complete the mechanical portion of the installation.

The electrical/instrumentation allowance (item 1.c) shall include the efforts necessary to provide power to the Hach CL 17 units as well as the sample pumps; to provide control of the sample pumps (to match existing); and to provide communication back to the control room (to match that of the existing units).

  1. Contractor shall slope the underground pipe at a 0.25-percent slope and install a sump for visual inspection at the low end (one sump for each underground pipe system, (3) total). Direction of slope shall be away from the injection point. For instance, the piping between the degasifiers and connection to the 42-inch pipe shall slope towards the degasifiers. See Figure 2 for sump detail.

SPECIFICATIONS

  1. Replace the Bid Form with the attached. Please note that two (2) analyzers are proposed to be installed. In addition, an electrical/instrumentation allowance has been added as item 1a.

DRAWINGS

1.Sheet G-001

  1. Revise the second sentence ofNote 4 to read:

“All piping to be sch 40 CPVC color code yellow with black direction of flow arrows every 10 feet on the above-grade portions only.”

  1. Revise Note 14 to read:

“All buried piping shall have proper identification detector tape installed at 12 inches below finished grade. In addition, Contractor shall installelectronic markers (Tempo Omni Markers as specified in the County’s Technical Specifications) above the pipe at all junctions, changes in direction and every 50 feet along the laying length of pipe.”

  1. Revise Note 29 to indicate that the Contractor shall use Weld-On 724 glue for pipe joints as manufactured by IPS Corporation or County approved equal.
  1. Add Note 31 to read:

“Contractor to provide re-lined record drawings to show field modifications. In addition, Contractor to provide both horizontal and vertical locations of the pipe every 100-feet and at changes in direction.”

2.Sheet M-501

  1. Replace Detail 4 with the attached.
  1. Add Detail 4a, which complements Detail 4.

Photo 1 – Existing Chlorine Residual Analyzers (right) at Blending Tank

Photo 2 – Existing Hach CL 17 at Lime Softening Recarbonation Basin

END OF ADDENDUM

DMN/Bidding/Addendum-1.docADDENDUM NO. 1

Tt# 200-08469-11001A-1060611