ISDS 



C. Site Evaluators 



**DeveIop a system of licensing private Site Evaluators, such as that 

 employed successfully in Maine since 1974. Responding to the demonstrated 

 unreliability and inconsistency of percolation tests, Maine instituted a system whereby 

 individuals having college degrees in Soil Science, Geology, or Forestry can apply to 

 operate as Site Evaluators. 



In Maine, the Evaluators must pass a three part written examination and a field 

 examination given by the state. Evaluators contraa with ISDS permit applicants to perform 

 comprehensive soil evaluations in accordance with Maine's soils-based evaluation criteria, 

 and are licensed to perform examinations for systems with up to 2000 gpd capacity. 

 Licensed engineers must evaluate site suitability for larger systems. Evaluation results are 

 presented to the applicant for use with the point-based permitting system, and copies are 

 forwarded to the town and the state Dept. of Human Services, Division of Health 

 Engineering. 



The Department communicates regularly with the Maine Association of Site Evaluators, 

 and considers that the evaluators accurately interpret the state's requirements. Privatizing 

 the most labor-intensive portion of the program allows the state to operate the entire 

 permitting program very efficiendy. 



D. StafHng 



♦♦♦Increase staff of ISDS Section or Groundwater Section, or develop joint 

 staffing capability among these two sections and the Freshwater wetlands 

 section to ensure that accurate site evaluation and system sizing decisions 

 can be effectively made, while providing for a reasonable tum-around time to the 

 applicant Hiring sufficient soil scientists, hydrogeologists, and engineers will require, at a 

 minimum, tripling the size of the ISDS Section staff, which is presenUy woricing overtime 

 under the existing program. 



SPECIAL CONSIDERATIONS IN EVALUATION OF DRAINAGE 

 PARAMETERS 



Findings and Concerns 



In many areas of the Bay watershed where a seasonal high water table occurs, 

 underground drainage devices are used to lower the water table artificially by intercepting 

 groundwater. These subdrains prove effective on sloping areas of seasonal high water 

 levels, and have been applied on a large scale to drain major housing developments in areas 

 of marginal site suitability. Placed upgradient from the proposed leach field site on single 

 lots, they are utilized to obtain permit approval for individual system. 



Use of subdrains creates a number of potential hazards: 



a) Partly because the potential effectiveness of the drains is reduced with distance from 

 the drain itself, the potential to intercept improperly treated ISDS effluent is 

 significant, particularly in level areas. Although the unreliable performance of 

 subdrains in level areas has led to use prohibitions in some states, even uphill 



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