Well Specifications for Greenough Lake Public Water Supply New Well

This document is a technical specification for the design and construction of a public water supply well to service a new campground loop at Greenough Lake Campground, located approximately 11 miles south of Red Lodge, Montana on the Custer-Gallatin National Forest (coordinates 45.055° N, 109.415° W). The well must service an estimated maximum of 50 persons per day across 28 RV camping sites and one host site. The project requires completion of a licensed water well contractor performing work in accordance with Montana Title 37 Chapter 43 MCA, Title 36 Chapter 21 ARM, and additional specifications detailed herein.

The well design calls for a minimum 25 feet of unperforated surface casing with a 10-inch nominal diameter, advanced to a 6-inch nominal diameter permanent casing to the producing aquifer at an anticipated total depth of 50-100 feet. Steel casing must meet ASTM A53 specifications with a minimum wall thickness of 0.250 inches. All casing joints require welding or screw coupling with watertight seals. The well requires a sanitary seal (bentonite or cement grout) with minimum 1.5-inch thickness between casings, unperforated casing to a minimum 25-foot depth, 18-inch minimum above finished grade or 100-year floodplain elevation (three feet for flood-prone sites), and temporary protective capping during construction. Upon completion, the contractor must perform well development, disinfection using chlorine solution at 50 mg/l concentration per standardized dosing table, and yield/drawdown testing at 1.5 times design capacity for minimum 24 hours at ≥30 gpm. Water quality testing must include microbiological analysis and chemical/radiological testing for primary and secondary contaminants. The well will be equipped with a monitor handpump selected by the Contracting Officer's Representative following development and testing. Geologic data collection, well logs, and all aquifer testing results must be submitted electronically to the Montana Department of Environmental Quality. Plumbness and alignment testing per AWWA A100 standards is required, with mechanical drift indicator surveys mandatory if alignment concerns arise during casing or screen installation.