DATE: April 8, 2015 TO: ALL PLAN HOLDERS PROJECT: Bistone

DATE:
April 8, 2015
TO:
ALL PLAN HOLDERS
PROJECT:
Bistone Municipal Water Supply District
TWDB No. 62536
Surface Water Treatment Plant 2014 Improvements
Competitive Sealed Proposal Procurement Method
ADDENDUM NO. 1
The Contract Documents, Technical Specifications, and Plans are hereby modified as
follows:
1.
Plan Sheet 6, Notes:
Note 5 shall be revised to read as follows:
Sample lines shall be schedule 80 PVC unless otherwise noted, and shall include
isolation valves at sample point and at connection to equipment.
2.
Plan Sheets 6 and 7, Free Chlorine Sample Tap:
The 1-inch free chlorine sample tap shall be relocated to the side of the 20-inch
ductile iron pipe.
3.
Plan Sheet 7, Total Chlorine Sample Pump:
The Contractor shall furnish and install a peristaltic sample pump to convey the total
chlorine sample from the 1-inch sample tap to the total chlorine analyzer inside the
UV-Oxidation Building. The sample pump shall be a variable speed Masterflex L/S
Economy Pump System with Easy-Load II Pump Head, Model No. EW-77910-20 by
Masterflex or Engineer approved equivalent. The sample pump system shall have a
flow range of 50 - 1,000 mL/min. The Contractor shall be responsible for furnishing
and installing all piping, fittings, valves, tubing, hose clamps, etc., required to convey
the sample and reduce the 1-inch PVC sample line to the tubing size recommended
by the pump manufacturer for the flow range specified above. All tubing shall be
ANSI/NSF 61 grade. The Contractor shall locate the pump on a pump shelf/base
positioned over the analyzer sump. The pump power cable shall be of sufficient
length to reach the closest receptacle. The pump shall be rated 120VAC, 1-phase,
60 HZ and shall be complete with a 3-conductor power cable that shall be of
sufficient length to reach the closest receptacle.
4.
Plan Sheet 7, Notes:
Note 3 shall be added to read as follows:
3. All above ground piping subject to freezing shall be insulated per Specification
Section 15260.
BM.021 Addendum 1 Electrical Attachment