Road improvement work is proceeding on schedule, according to town engineer Thomas Hayes.  The program got underway last month and will continue through the end of August. Contractors are repaving all or portions of 19  roads; 14 are undergoing simple resurfacing work, while five are being reconstructed. This year’s program also involves microsurfacing, or maintenance work, on about 20  additional roads. Less extensive than regular repaving, microsurfacing involves resealing cracks or applying a thin surface layer to the street. Hayes said the maintenance work was completed in three days earlier this month. The overall $1.7 million program — $1.4 million  for the resurfacing and $300,000  for the microsurfacing — is being funded through a combination of funds allotted through the state’s Chapter 90 local road improvement program, and town money. P.J. Albert Inc. of Fitchburg  is undertaking the paving work, and Sealcoating Inc. of Hingham is handling the microsurfacing.