Starting with alignment of our cost structure with the demand environment, we are rightsizing our workforce through furloughs and other reductions and implemented a nonbillable hiring and wage freeze, and we restricted all travel.
From a liquidity perspective, we drew down $150 million on our revolver to strengthen our balance sheet in the event that crisis worsens.
We have reset our net CapEx spend plans for 2020, and we've lowered our expected spend by more than $50 million to preserve capital and support our free cash flow for the year.
Revenues rose 10% from a year ago as both operating segments recorded solid growth.
At the same time, our adjusted EBITDA increased to a record $122.6 million, driven by our mix of high-value waste streams and high utilization, augmented by projects and emergency response work.
Our adjusted EBITDA margin increased 130 basis points to 14.3%.
Environmental Services revenue grew 11% based by contributions from our facilities network and Field Services group and aided by warmer weather nearly all quarter.
Adjusted EBITDA growth of 22% was driven by business mix, disposal volumes, and emergency response revenue.
Emergency response work totaled $21 million, representing COVID-19 de-con work and a cleanup of a chemical plant fire.
Our disposal facilities saw impressive volumes this quarter as incinerator utilization increased to 86% and landfill tonnage grew 39%.
Our average price per pound for incineration in Q1 was up 11%, reflecting the record level of high-margin direct burn streams that we gathered.
Safety-Kleen revenue was up 8%, primarily by growth in the SK Oil business.
While parts washer services were flat with the prior year, waste ore collection was up slightly to 55 million gallons, blended products accounted for 25% of volume in the quarter, and our direct volume was 7%.
But the oil shock sparked by the global outbreak of the coronavirus, IMO 2020 has largely been sidelined, and base oil has fallen by $1 a gallon.
As I mentioned earlier, we are reducing our planned net CapEx by more than $50 million.
Since we began executing our divestiture program several years ago, we've sold seven businesses for approximately $120 million in proceeds.
In addition, we'll look to repay the $150 million on the revolver as soon as this crisis shows signs of nearing an end.
Revenue grew nearly $78 million, while adjusted EBITDA grew by nearly $21 million.
Our gross margin increased by 160 basis points from a year ago.
SG&A expenses were up $14.5 million in the quarter due to the higher revenue, investments in our employees, and some onetime expenses from last year -- onetime items from last year.
Depreciation and amortization in Q1 was down slightly to $47.5 million.
For 2020, we expect depreciation and amortization in the range of $285 million to $295 million, which is a little lower than last year.
Income from operations increased 92% to $45.5 million, a first-quarter record, reflecting the combination of our revenue growth and improved gross profit.
On a GAAP basis, earnings per share was $0.21 in Q1 versus $0.02 a year ago.
Our adjusted earnings per share was $0.28.
As Alan mentioned, we drew $150 million on our revolver during the first quarter which increased our cash and short-term marketable securities to $494.3 million at quarter end.
Current and long-term debt obligations at quarter end rose to $1.7 billion, reflecting the drawdown on our revolver.
Our weighted average cost of debt is now 4.3% with a healthy mix of fixed and variable debt.
Leverage on a net debt basis was 2.2x for the trailing 12 months ended March 31.
Cash from operations in Q1 was up slightly at -- to $33.7 million.
CapEx, net of disposals and the purchase of our headquarters, was $59.9 million, up from a year ago, resulting in adjusted free cash flow in the quarter of a negative $26.2 million, which is consistent with prior year and our expectations.
For the year, we are now targeting CapEx, net of disposals and purchase of our headquarters in a range of $140 million to $160 million.
During the quarter, we repurchased approximately 300,000 shares of our stock at an average price of $57.41 a share for a total of $17.3 million.
We're hopeful we'll be able to reinstate guidance with our Q2 earnings announcement, provided markets have stabilized.

Summary:
Starting with alignment of our cost structure with the demand environment, we are rightsizing our workforce through furloughs and other reductions and implemented a nonbillable hiring and wage freeze, and we restricted all travel.
From a liquidity perspective, we drew down $150 million on our revolver to strengthen our balance sheet in the event that crisis worsens.
We have reset our net CapEx spend plans for 2020, and we've lowered our expected spend by more than $50 million to preserve capital and support our free cash flow for the year.
As I mentioned earlier, we are reducing our planned net CapEx by more than $50 million.
In addition, we'll look to repay the $150 million on the revolver as soon as this crisis shows signs of nearing an end.
On a GAAP basis, earnings per share was $0.21 in Q1 versus $0.02 a year ago.
Our adjusted earnings per share was $0.28.
As Alan mentioned, we drew $150 million on our revolver during the first quarter which increased our cash and short-term marketable securities to $494.3 million at quarter end.
We're hopeful we'll be able to reinstate guidance with our Q2 earnings announcement, provided markets have stabilized.