Storm Water Management Program Support, Permitting, and Sampling, Kirtland AFB

kafb momitoringNCS provided services for storm water monitoring and station maintenance. The contract included NPDES permitting and compliance requirement, field inspections, outfall stations site improvements as well as storm water sample collection and analysis.

Storm Water Monitoring Support, Operations and Maintenance: Storm water from the Family Housing areas and other non-industrialized are within the Kirtland AFB boundaries within the MS4 permit area drain directly into the City of Albuquerque storm sewer system. NCS was tasked with the responsibilities of storm water sampling/monitoring (visual examination and laboratory analysis) of eight stations during the performance period. This included station programming to ensure proper operation and effective collection of storm water samples and specific maintenance of the monitoring stations.

Storm Water Monitoring Stations, Condition Assessment an Refurbishment: This task specifically outlined the refurbishment calibration and upgrade of five ISCO 6700 and four ISCO 6712 samplers. NCS replaced the external sampling components devices, sensor containers and Teflon/conduit that houses the wiring and tubes. NC further installed four outdoor enclosure units to house ISCO samplers an permanently installed three outdoor enclosures and ISCO samplers.

Washington Aquaduct Water Treatment Process

US Army Corp of Engineers logoThe design included an investigation into the most feasible method to feed chloramine, as a secondary disinfectant, at both plants. The Dalecarlia and McMillan Water Treatment Plants produce an average of 220 MGD for the District of Columbia, Arlington, VA, Falls Church, VA, and portions of Fairfax County, VA. The design of the chloramination process consists of revisions and upgrades to the existing chlorination systems (primary disinfection), and the addition of new facilities for ammonia chemical storage, feed and monitoring (secondary disinfection). Improvements to the existing chlorination process includes replacement chlorinators and evaporators, additional chemical feed lines (chlorine for primary disinfection and lime for pH adjustments), clearwell baffle wall configuration design (maximize contact time in existing WTP finished water storage), and improvements to process monitoring.

Washington Aquaduct

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The design process included a chemical kinetics treatability study and a feasibility study for both WTP facilities. These concurrent studies determined the most efficient and cost effective method of providing ammonia storage, feed, and monitoring and utilizes bulk aqua ammonia storage and feed facilities. The kinetics testing determined that the ammonia feed system will minimize DBP formations following the primary disinfection phase of the upgraded water treatment process. The new ammonia facilities at each plant will require 3,000 sf for chemical storage, safety scrubbers, chemical feed equipment, and monitoring/header piping devices.

The project design scope was expanded to address other operational issues at the Dalecarlia and McMillan Water Treatment Plants. The additional scope items for the Dalecarlia WTP included the conversion of the bulk lime handling facility from bucket elevator and screw conveyor to a pneumatic conveying system; the replacement of the polymer feed and storage facilities; the conversion of the existing dry alum storage and feed facilities with a liquid coagulant storage and feed system; replacement of an existing chlorine gas scrubber with a deep bed dry chemical type scrubber; and water proofing the top slab of a buried 30 million gallon clearwell. The additional scope items for the McMillan WTP included replacement of three lime feeders and slakers and waterproofing the top slab of a buried 30 million gallon clearwell. The additional scope items for the McMillan WTP included replacement of three lime feeders and slakers and waterproofing the top slab of a buried clearwell.

Albuquerque Metro Area Flood Control Authority

Albuquerque Metro Flood Control Authority logoCritical environmental and water quality issues and complex regulatory requirements are major concerns for large storm water utilities. NCS offers relevant knowledge and experience to help AMAFCA deal with these issues and regulations, as we provide the following storm water related services:

  • Storm Water Permitting and Storm Water Pollution Prevention Plan (SWPPP) review.
  • Multi-sector and regional storm water permits.
  • Municipal Separate Storm Sewer System (MS4) permitting.
  • Storm drain optimization studies and master planning.
  • Water quality assessments, field inspections, and flow monitoring.
  • Storm water sampling and analysis.
  • Design of water quality enhancement features.
  • In-stream monitoring along the Rio Grande.
  • MS-4 construction inspections.

City of Avondale

Water Quality Master Plan

  • NCS developed a Master Plan to mitigate drinking water quality issues such as chromium, TDS, nitrate and arsenic.
  • Based on the results of the evaluation, treatment technologies were selected and a Capital Improvements Plan (CIP) was identified to mitigate these constituents.
  • Several processes, depending on the well site, were identified for implementation, these included GAC, ion exchange (IX), reverse osmosis (RO), and coagulation/ filtration (CF) technologies along with blending.

Northside Coagulation/Filtration Facility

  • NCS served as process design consultant for a 6,000 gpm arsenic treatment facility which treats groundwater from three feed facilities.
  • The project included residuals handling components, and chemical feed facilities for pH adjustment.
  • NCS provided construction management (CM) services including submittal review, commissioning, startup, training, and operations and maintenance manuals (O&M).

Ion Exchange System Specifications and Bid Review

  • NCS assisted with the procurement of a 3 MGD nitrate treatment IX facility.
  • During negotiations, NCS reduced the annual equipment costs from $300,000 to $180,000 over the 10-year term.
  • NCS subsequently optimized the design and operation of the system to save costs and improve performance.

Northside Steel Tank Rehabilitation

  • NCS designed improvements and managed construction for the rehabilitation of two
    0.6 MG steel tanks.
  • The project included structural, safety, and piping improvements; and enhanced
    coating system with a 20-year warranty

Process Optimization and Disinfection By-Products Study, Ocean City, MD

A study of potential alternatives for optimizing treatment performance (for oxidation and removal of iron and manganese) and reduction of disinfection by-products (primarily Trihalomethanes) to meet the requirements of the Stage 2 Disinfection By-Products Rule (Stage 2 DBPR) is on-going.

A preliminary assessment report has been completed and bench-scale testing conducted with the support of NCS Engineers. Preliminary results have shown that chlorine dioxide has the potential for improved oxidation of iron and manganese as well as minimizing the formation of disinfection byproducts. Testing as related to the implementation of chloramination (combined chlorine and ammonia) has also shown the potential to result in significant reduction of Trihalomethanes (THMs).

Additional bench scale testing is being conducted with continued support from NCS Engineers to confirm earlier test data and to determine whether various process combinations are feasible for meeting the Stage 2 DBPR requirements without the need to convert to chloramination.