Consideration and Approval of Proprietary Purchase:  Purchase of Saf-T-Chlor dry sodium chlorite water treatment chemicals from CDG Environmental in an amount not to exceed $200,000, annually.
 

1. Approve the Purchase of Saf-T-Chlor dry sodium chlorite water treatment chemicals from CDG Environmental, LLC in an amount not to exceed $200,000, annually; and
2. Authorize the City Manager to execute all necessary documents.

The Water Production Section of Flagstaff Water Services uses a chlorine dioxide generator used in surface water treatment at the Lake Mary Water Treatment Plant. The chlorine dioxide generator was installed by CDG Environmental, LLC in 2008. It requires the use of the proprietary chemical Saf-T-Chlor dry sodium chlorite, requested in this purchase, to produce chlorine dioxide on-site. Using chlorine dioxide and the associated generator as a pre-treatment method works well for treating metals such as iron amd manganese and as a disinfectant for bacteria, protozoa, algae and taste and odor compounds without creating disinfectant by-products (DBPs). In years of abundant surface water, such as 2020 and 2023 surface water production can account for nearly 50% daily potable water produced for the City of Flagstaff and nearly 40% total water produced on annual basis. Surface water production can have one third the electrical demand compared to groundwater production. Purchasing Saf-T-Chlor and using chlorine dioxide as a pre-treatment oxidizer is necessary to maintain current treatment processes and maximize the use of surface water from Upper Lake Mary.

Water Production annually budgets for chemical expenditures in the Drinking Water Fund under account 202-08-301-1011-0-4362 with a total budget of $408,200 in FY2024-25 to cover the costs associated with all chemicals used in water treatment.

The City Council last approved this proprietary purchase on April 16, 2019.

1. Approve the purchase of Saf-T-Chlor dry sodium chlorite from CDG Environmental, LLC to to be used with the onsite chlorine dioxide generator at the Lake Mary Water Treatment Plant for surface water production; or
2. Reject the purchase of Saf-T-Chlor dry sodium chlorite from CDG Environmental, LLC and leave the water production section with the options of either finding another chlorine dioxide generator or other pre-treatment/pre-oxidation system to use; or
3. Return to using chlorine for raw water pre-oxidation with the known side effects of disinfection by-product (DBP) production.

In 2008, the Lake Mary Water Treatment Plant upgraded the treatment process by adding an onsite chlorine dioxide generator to be able to apply chlorine dioxide to raw surface water from Upper Lake Mary.  CDG Environmental, LLC was chosen as the supplier of the equipment which utilizes Saf-T-Chlor, a proprietary dry form of sodium chlorite that is used to make chlorine dioxide on-site.  Due to the hazardous nature of chlorine dioxide it is illegal to ship the chemical and requires on-site generation.  The use of chlorine dioxide as pre-treatment for surface water helps oxidize iron and manganese, reduce taste and odor, disinfect water containing bacteria, parasites or algae without creating disinfectant by-products (DBPs).

As required under the Procurement Code, the information regarding the proprietary status of the Saf-T-Chlor dry sodium chlorite and drums from CDG Environmental, LLC was provided to purchasing. One of the factors considered was the safety inherent in Saf-T-Chlor as the material is itself stable, shipped in sealed drums from the manufacturer, and represents minimal risk to employees and the public.

1.  Safe and Healthy Community
2.  Sustainable and Innovative Infrastructure:  Deliver outstanding services to residents through a healthy well-maintained water services.

Policy WR 2.2:  Maintain and develop facilities to provide reliable, safe, and cost effective water, wastewater, and reclaimed water services.

1.  CR-1:  Strengthen existing community systems to create resilience to both short-term shocks and long term change.
2.  WS-1:  Improve water infrastructure and expand water reuse.

None

1.  Objective 6:  Ensure Adequate Water Resources and Plant for Climate Change
2.  Objective 7:  Maintain Excellent Water Quality