Frequently Asked Questions

  1. How should VDH should handle previously approved subdivisions, certification letters, or expired permits involving pads on slopes exceeding 10%.

    2. Answer. Follow the grandfather clause in the Regulations. The new permit should comply with the Regulations to the greatest extend possible and if VDH is asked to renew a permit on a slope >10%, staff should reissue the permit following the grandfather clause.

  2. Are pads required to comply with the center-to-center spacing requirements contained in the Regulations?

    3. Answer. No.

  3. Please clarify how site evaluators (AOSEs and EHSs) are to implement the separation distance to impervious strata for shallow-placed systems.

    4. Answer. Table 4.3 indicates that the separation distance to bedrock is 18 inches and the footnote refers to Section 12VAC 5-610 -596.C.2 of the regulations. Section 12VAC 5-610 -596.C.2 states that to assure adequate hydraulic dispersal capacity, bedrock and impervious strata may not occur within 18 inches of the trench bottom. The intent of this section is to prevent failures caused by an inadequate offset to impervious strata.

    Some site evaluators have incorrectly assumed all bedrock and Cr soil horizons are impervious. The regulations do not specify the offset to pervious rock strata. This issue was raised in 2000 when the Sewage Handling and Disposal Regulations were enacted. VDH determined that the offset to pervious rock strata, including pervious bedrock and pervious Cr horizons, is 12”. This is reflected in training materials and charts provided during training courses at the time the regulations were enacted.

    In summary, the offset to pervious bedrock or pervious Cr horizons for shallow- placed systems is 12”. The offset to impervious strata for shallow-placed systems is 18”. When performing soil evaluations, it is important that all site evaluators describe the transmissivity of bedrock and Cr horizons as either pervious or impervious.

  4. GMPs 112.A, 114.A, 118.A, 144, and 145 contain a waiver, granted by the commissioner, to the separation distance to impervious strata. This waiver allows the separation distance to be reduced from 18 inches to a distance not less than 12 inches when a professional engineer certifies in writing that they have evaluated the hydraulic capacity of the site to disperse wastewater. The professional engineer must indicate that in their professional opinion, water mounding will not encroach on the separation required between the infiltrative surface of the soil absorption system and water table. Am I correct in assuming the engineer must run hydraulic conductivity tests and submit mounding calculations to support their conclusion that the separation distance require will be met?

    5. Answer. No. The method the engineer uses to make this determination is not specified in the policy, thus allowing each engineer to make this determination using their best professional judgment on a case by case basis. All that is required is a written statement from the professional engineer stating: they have evaluated the hydraulic capacity of the site to disperse wastewater and that in their professional opinion; water mounding will not encroach on the separation distance required in the relevant table (the table number varies among the GMPs).

  5. GMPs 144 and 145 are experimental. The backup and bonding requirements were not waived. How should field staff handle issuing permits and complying with these requirements?

    6. Answer. The short answer is neither of these requirements should be an impediment to issuing a permit for these specific systems. Bonding is not required. A reserve area is required; systems approved via GMP 112A, 114A or 118A may be specified as the back-up. A detailed answer follows.

    The site conditions required for either a GMP #144 or #145 system are identical to those required for GMP #112A, #114A, and #118A systems. Any of these systems that have been granted General Approval would therefore be suitable for use as a backup system. Bonding is only one of a variety of financial assurances that may be used. Given the performance history of the three systems with General Approval the Department felt that in general, bonding would be a barrier to the implementation and use of these systems and would be inconsistent with 12 VAC 5-610-441.A 1 that states the policy of the division is to encourage the development of mew methods, processes, and equipment…for the treatment and disposal of sewage;” While that section was not explicitly waived (and may be appropriate in some situations) the Department believes the cost of the systems is generally consistent with connection to a public sewerage system and not warranted in most instances. In short, the value of the property and interests of the homeowner to protect the value of their property are sufficient to assure that repairs on these systems will be made, in those instances where it becomes necessary to make a repair.