Provencher Engineering, LLC
6 Wasserman Heights
Merrimack, NH 03054
Phone/Fax: (603) 883-4444

Simrah Gardens

Groundwater Discharge Permit for Wastewater Treat-

ment, Hydrogeologic Report, & Leach Field Design

SIMRAH GARDENSCentral Street, Hudson, Massachusetts

Despite having public sewer located right in the project's frontage on Central Street, sewer access was not allowed to the project by the town. Faced with the apparent inability to move forward with the project, Provencher Engineering provided wastewater master planning for on-site treatment and disposal for this 36,000 GPD proposed multi-unit residential development. We conducted soil evaluations with the DEP, borings and monitoring well installtion with a driller, and hydraulic conductivity (slug) tests using our transducers and test equipment. We read several monitoring wells for groundwater level, calculated a seasonal high adjustment to the water table using the Frimpter Method, and contoured the seasonal high water table. 

Then we created a hydrogeologic model and determined the mounding effects to the water table elevation due to the recharge of the treated effluent, and contoured the proposed mounded groundwater table. The model was also used to design a retaining wall bordering the leach field, which was required to reduce off-grading and to prevent breakout of the treated effluent. The WWTP was designed by Linden Associates, and the site surveyor and civil designer was Connorstone Engineering.

We successfully secured a Groundwater Discharge Permit (GWDP) from MA DEP for treatment of the wastewater using a membrane bio-reactor (MBR), and for discharge of the treated effluent into the ground. Once the permit was granted, the town subsequently reconsidered the proponent's request, and granted permission to tie the proposed development into the town's public sewer system. Although our on-site wastewater treatment and disposal system was never constructed, it was a critical tool used to negotiate the public sewer connection.

Reference available upon request: