Addendum_Items_20230828_0008.pdf

Project Number HDR Client Name Issue Date

Engineering Master Specifications Library Deliverable Type

ADDENDUM FORM

00 91 13 - 1 ENGINEERING MASTER

CHANGES TO SPECIFICATIONS

#.# Section 03 11 13 – Formwork: Delete Paragraph 3.2.F. Straight forms are not allowed for circular clarifier walls.

#.# Section 32 12 16 – Asphaltic Concrete Vehicular Paving: Add Paragraph 2.2.B “Recycled Asphalt

Product (RAP) may be utilized up to 15% of the total weight of the mixture.”

#.# Section 32 12 16 – Asphaltic Concrete Vehicular Paving: Delete Paragraph 3.1.C., prime coat is not required.

#.# Section 41 12 13 – Conveyors – Screw: Under paragraph 2.1.A.1. add “Spirac”.

#.# Section 43 41 43 – Polyethylene Chemical Tanks: Under paragraph 2.1.A. add “Assmann”.

#.# Section 46 13 01 – Fiberglass Covers – Dome Type: Under paragraph 2.1.A. add “Midwestern

Fabricators”.

#.# Section 46 33 33 – Liquid Polymer Feed Equipment: Under paragraph 2.1.A.1. add “VeloDyne”.

#.# Section 46 41 00 – Mixers: Under paragraph 2.1.A. add “Sulzer”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A. delete “Anoxic and Oxic Basin mixers (16 total units)” and replace with “Anoxic, Oxic, and Equalization Basin mixers (17 total)”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.1. delete equipment tags and replace with “(04-

ABMX-1A1, 04-ABMX-2A1, 05-ABMX-1B4, and 05-ABMX-2B4)”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.2. delete equipment tags and replace with “(04-

ABMX-1A2, 04-ABMX-1A3, 04-ABMX-2A2, 04-ABMX-2A3, 05-ABMX-1B1, 05-ABMX-1B2,

05-ABMX-1B3, 05-ABMX-1B5, 05-ABMX-2B1, 05-ABMX-2B2, 05-ABMX-2B3, and 05-

ABMX-2B5)”.

#.# Section 46 41 00 – Mixers: Delete Paragraph 2.3.A.3. and replace with:

“Equalization Mixers (03-EQMX-1)

a. Mixer Unit: TR30-1.89-8/8

b. Mast/Rail: AVU60 mast/rail”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.5. delete “& OX2”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.6. delete “OX1” and replace with “Oxic”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.8. delete “& OX2”.

#.# Section 46 41 00 – Mixers: In Paragraph 2.3.A.9. delete “OX1” and replace with “Oxic”.

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Add Paragraph

1.1.A.1.b. “Bridge Supported”.

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Delete Paragraph

1.3.A.3. NACE inspection is not required.

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Delete Paragraph 1.3.B

“Independent Design Evaluation of Drive”.

ADDENDUM FORM

00 91 13 - 2 ENGINEERING MASTER

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Delete Paragraph 2.3.A and Replace with “Bridge: 316 Stainless Steel”.

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Delete Paragraph 2.3.Y.

Weirs and baffles are specified in Section 06 85 14.

#.# Section 46 43 24 – Spiral Scraper Circular Secondary Clarifier Equipment: Delete Paragraph 2.4.C

“Center Pier” and Paragraph 2.4.E. “Center Drive Cage”. These items do not apply as the mechanism is bridge supported and will utilize a worm gear.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.3.B.1, delete

“Equalization (EQ)”.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: Delete Paragraphs 1.3.B.1.a, 1.3.B.1.b., and 1.3.B.1.c.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.3.B.1.g, delete “300 scfm” and replace with “42 scfm”.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.5.A.1.f.1.b., delete “10 ft SWD” and replace with “11.5 ft SWD”.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.5.A.1.f.1.c., delete “30 scfm/kcf” and replace with “15 scfm/kcf”.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.5.A.1.f.1.e., delete “85 scfm” and replace with “42 scfm”.

#.# Section 46 51 21 – Aeration System – Course Bubble Type: In Paragraph 1.6.A.4.f., delete “12 supports” and replace with “3 supports”.

#.# Section 46 51 32 – Flexible Membrane Diffusers: After Paragraphs 2.3.A.4., add “and installed”.

#.# Section 46 51 32 – Flexible Membrane Diffusers: After Paragraphs 2.3.A.4.a. and 2.3.A.4.b, add

“as required based on manufacturer design calculations”.

#.# Section 46 51 32 – Flexible Membrane Diffusers: Delete Paragraph 2.3.A.5.

#.# Section 46 51 32 – Flexible Membrane Diffusers: Delete Paragraph 2.3.A.6. and table, Replace with the following paragraph and table: “Maximum airflow per basin (each train): 680 scfm. Total airflow both trains: 1,360 scfm”.

Basin 1AX1a 1AX1b 1OX1a 1OX1b 1OX1c 1OX1d 1OX1e 1AX2 1OX2

Depth 16 16 16 16 16 16 16 16 16

Length 5 4.75 13.25 25 7 22.75 8 9.75 11

Width 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5

Volume, cu ft 440 418 1,166 2,200 616 2,002 704 858 968

Peak Air Flow, scfm - 95 95 150 40 120 30 75 75

#.# Section 46 53 44 – Vertical Upflow Continuous Backwash Sand Filter: Add paragraph 1.1.A.2.e.

“Access platform extending from building second level over both new filters”.

ADDENDUM FORM

00 91 13 - 3 ENGINEERING MASTER

#.# Section 46 53 44 – Vertical Upflow Continuous Backwash Sand Filter: Add paragraph 2.2.D.8.f.

“Access Platform: Aluminum”.

#.# Section 46 53 44 – Vertical Upflow Continuous Backwash Sand Filter: Delete paragraph 2.3.B.1.c.

#.# Section 46 76 33 – Centrifuges: At the end of Paragraph 1.6.A. add “equivalent to or greater than the current operating equipment”.

#.# Section 46 76 33 – Centrifuges: Delete the Table in Paragraph 1.6.B. and replace with the following table:

Characteristic Range Value Used for Performance

Acceptance

Schedule 5 days/week, 3-8hrs/day 5 days/week, 3-8hrs/day

Feed Solids Concentration (%T.S.) 0.4 – 1.0% 0.4 – 1.0%

Individual Centrifuge Solids

Loading Rate 40-60 lbs/hr

Hydraulic loading rate

15-25 GPM 20 GPM

Total Volatile Solids (% T.V.S.) Max 65% pH 6.0 – 7.5

#.# Section 46 76 33 – Centrifuges: Delete Paragraph 1.6.C. and replace with “The CENTRIFUGE

MANUFACTURER shall meet a guaranteed centrifuge performance equal to or greater than current centrifuge performance based lab testing results and/or existing centrifuge historical performance.”

Parameter Performance Guarantee

Cake Solids Equal to or Greater than 21.0% TS

Active Polymer

Use

Equal to or Less than 20 lbs/dry ton

Solids Capture Equal to or Greater than 95.0%

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.B.1. Change “3 IN” to “1.5 IN”. In paragraph

2.3.B.2. Change “Flanged” to “Feed pipe”.

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.C.1.a.1) Change “3,250 rpm” to “4,250 rpm”.

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.C.2.a. Change “4.5:1” to “4.0:1”.

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.C.3.a. Change “20” to “10”.

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.C.4.a. Add “Maximum”.

#.# Section 46 76 33 – Centrifuges: In paragraph 2.3.C.6. Change “3,250” to “5,000”.

#.# Section 46 76 33 – Centrifuges: At the end of paragraph 3.5.A. Add “the manufacturer will conduct performance testing to demonstrate acceptable process performance as specified in section 1.6 above.”.

#.# Section 46 76 33 – Centrifuges: Delete Paragraph 3.5.G. and 3.5.H.4. including reimbursement calculations.

ADDENDUM FORM

00 91 13 - 4 ENGINEERING MASTER

CHANGES TO DRAWINGS

#.# Drawing 00-D004, Process Flow Diagrams: Modify the Drawing as shown and indicated on attached Sketch.

#.# Drawing 09-Y612, Instrumentation P&ID – Sand Filters and Reaeration Column: Delete Sample

Pumps (02-SAP-1, 02-SAP-2, 02-SAP-3, and 02-SAP-4) and Control Panels (CP 02-SAP-1 and CP

02-SAP-2).

ATTACHMENTS

The items listed below and bound following this document’s “End of Addendum” designation, are part of this Addendum.

#.# Drawings attachments hereto are as follows:

• Markups to Drawing 00-D004 – Process Flow Diagrams.