G.5 Groundwater Monitoring

Groundwater monitoring wells (including the minimum subsurface investigation depth) shall be installed as determined in  G.2.3 Simple Subsurface Investigation under the direct supervision of a licensed professional. The minimum number of groundwater monitoring wells, duration of monitoring, and frequency of monitoring are summarized in Table II-5.4. A report shall be developed that is prepared by a licensed professional and includes a map detailing the locations of the monitoring wells relative to the project site and a description of the groundwater levels relative to the investigation depth and vertical separation requirements provided in G.2 Subsurface Investigation. Refer to report submittal requirements in Volume II, Chapter 1.

Groundwater monitoring is not required in the following situations:

• Elevation data measured at project monitoring wells shows groundwater levels within the investigation depth and vertical separation requirements summarized in G.2 Subsurface Investigation.

• Available groundwater elevation data within 50 feet of the proposed infiltration BMP shows the highest measured groundwater level to be at least 10 feet below the bottom of the proposed infiltration BMP or if the initial groundwater measurement is more than 15 feet below the bottom of the proposed infiltration BMP.

In these situations, no further investigation is required to meet onsite, flow control, or runoff treatment requirements. These exceptions do not apply to deep infiltration BMPs.