Glossary and abbreviations

Class

Synonym for (leak) grade; see Leak grade

DPU

Mass. Department of Public Utilities

GOL

Grant of Location requests from National Grid to the City of Newton to place gas pipes in a new location under the street.

Grade

See Leak grade

GREC

GSEP Reconciliation reports which are filed annually with the DPU; see GSEP plan

GSEP

National Grid Gas System Enhancement Program

GSEP plan

Prospective plans for repair and replacement of gas mains which are filed annually with the DPU under auspices of GSEP; see GREC

G3SEI

Grade 3 SEI leak, where grade 3 leaks are otherwise "non-hazardous and are expected to remain non-hazardous;" see Leak grade

Leak class

Synonym for leak grade; see Leak grade

Leak extent

Square feet of ground over a leak where gas can be detected

Leak grade

The DPU has defined various gas leak grades/classes:

• Grade 1 leaks are hazardous and must be repaired immediately.
• Grade 2 leaks are non-hazardous, but could become hazardous in the near future and must be repaired within a year.
• Grade 3 leaks are non-hazardous and are expected to remain non-hazardous.
  • Grade 3 leaks initially designated after 1/1/2018 are required to be repaired or eliminated within 8 years.
  • Grade 3 SEI are grade 3 leaks larger than 2,000 square feet as measured by the leak extent method and are required to be repaired in 1-3 years.

NGrid

National Grid, the gas utility which serves Newton

PM

Paint markings on street made by DigSafe

PW

Weekly street opening plans distributed by City of Newton Department of Public Works

RL

Reported leak whose status is regularly reported by National Grid

SEI

A leak of Significant Environmental Impact, defined as 2,000 sq ft or more of leak extent

TG

Yellow small circle plastic marker in street

3SEI

See G3SEI