projects

Arsenic Control and Chemical Treatment Facility

Newfields, New Hampshire

Client: Newfields Water and Sewer District

Services

  • Bidding Administration
  • Construction Phase Services
  • Coordination with state regulators
  • Design
  • Evaluation
  • Funding Assistance

Project Summary

When testing of a deep bedrock well in the Newfields Water District, a small water supplier with approximately 175 services, showed arsenic levels above the 10 µg/l federal limit, they asked us for help. Data from the District’s remaining sources (three shallow gravel packed wells) showed that no arsenic was present, therefore our engineers concluded that source blending would work, rather than a typical but costly treatment option, such as adsorption on alumina, reverse osmosis membrane separation, or ion exchange.

To verify this approach we conducted a bench top study to ascertain that the results of blending would result in an acceptable water supply. This option provides comparable first consumer arsenic levels while eliminating approximately $120,000 in capital costs, a significant concern for a supplier of this size.

The new facility, currently being constructed, combines water from all four wells in proper proportion and includes a chemical feed system to adjust pH and alkalinity to meet the lead and copper rule. Knowing that source water characteristics can change over time, the design features a knockout wall should a treatment system be required at a future date. To minimize the financial impact to the District, Hoyle, Tanner assembled a funding package consisting of a low interest SRF Loan and several grants. The District Commissioners were pleased with this solution which allows them to continue to fulfill their mission of providing quality water at the lowest cost and are looking forward to their new facility coming online.

Click on thumbnail to view