Page 15 - HEPACO 401(k) Summary Plan Description

Your vesting percentage will be 100% if you are working for us:

· On or after the date you reach normal retirement age (see Part 4).

· On the date you become totally disabled, as defined in the plan.

· On the date you die.

Before that date, the schedule below determines your vesting percentage:

Years of Vesting Service Vesting Percentage

Less than 1 0
1 25
2 50
3 75
4 or more 100

If the plan is amended to change the vesting schedule and you are a participant when the
plan is amended, your vesting percentage won't be less than it would have been had the
plan continued unchanged.

Vesting service means the sum of your years of service. You have one year of service
for each service period in which you have 1,000 or more hours of service. A service period
is a one-year period ending on December 31. An hour of service is each hour of paid
working time. In addition, it includes up to 501 hours during any one period of paid
non-working time, such as paid vacation.

Vesting service includes service with:

· Hazardous Environmental Products Abatement Co.

· IMS Environmental Services, Inc.

Before Your Vesting Percentage Is 100%

If you have a forfeiture date, you forfeit (lose the right to) any part of your account that is
not vested. You do not forfeit anything if your vesting percentage for all contributions to
your account is 100%. You have a forfeiture date on the last day of five consecutive
one-year breaks in service.

If you stop working for us before your vesting percentage is 100% and then die, your
vesting percentage does not change and the part of your account that is not vested
becomes a forfeiture.

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